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uncinate process Re: Wet sinus & bronchial closure

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  • DDeden
    Marc, is the nasal uncinate process an entirely different structure than the uncinate process in birds and manicopteran dinos? They are both significant in
    Message 1 of 7 , Nov 8, 2007
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      Marc, is the nasal uncinate process an entirely different structure
      than the uncinate process in birds and manicopteran dinos? They are
      both significant in respiration rhythm and possibly breath holding
      AFAICT. (The nasopulmonary reflex relates to sneezing and MDR).

      9 Isobe M, Murakami G, Kataura A. Variations of the uncinate process
      of the lateral nasal wall with clinical implications. Clin Anatomy
      1998;11:295-303.
      ===

      --- In AAT@yahoogroups.com, "DDeden" <alas_my_loves@...> wrote:
      >
      > Very interesting article by Croatian Medical Journal, connects stimuli
      > of inferior conchae to bronchial closure and HR decrease (MDR).
      >
      > See ** 1/2 way down for specific connections, if in hurry.
      >
      > December 1998 (Volume 39, Number 4)
      > Influence of Nasal Fontanel Receptors on the Regulation of
      > Tracheobronchal Vagal Tone
      > Damir Mili�i�, Ranko Mladina1, Davorin �ani�, Drago Prgomet, Dinko
      Leovi�
      > Department of Otorhinolaryngology and Cervicofacial Surgery, Dr. Josip
      > Ben�evi� General Hospital, Slavonski Brod; and 1Department of
      > Otorhinolaryngology, University Hospital Center Zagreb, Zagreb, Croatia
      >
      > Aim. To test the hypothesis according that the receptors located in
      > the nasal fontanels influence the regulation of the tracheobronchial
      > tree vagus tone.
      > Methods. Changes in respiratory parameters (forced expiratory volume
      > in the first second- FEV1 and total resistance- Rt) occurring
      > consequentially to light mechanical nasal stimulation were determined
      > in healthy volunteer, non-smokers using spirometric and body
      > plethysmographic measurements. The parameters were measured before and
      > at 15 and 60 min after mechanical stimulation with cotton pledge.
      > Results. In subjects in whom the middle nasal meatus was stimulated by
      > a cotton pledge soaked in saline, FEV1 decreased (p=0.01) and Rt
      > increased (p=0.03). In subjects in whom the middle nasal meatus was
      > stimulated by a cotton pledge soaked in 5% cocaine solution, no change
      > was observed. In the control group of subjects, in whom the inferior
      > nasal concha was stimulated by a cotton pledge soaked in saline, only
      > a statistically significant decrease for FEV1 (p=0.04) was found.
      > Conclusion. There is a reflex communication between the nasal fontanel
      > receptors and lungs, which is regulating the tracheobronchial vagal
      > tone and resistance in lung airways. Further studies of this important
      > physiologic relation are needed.
      >
      > Key words: bronchoconstriction; lung volume measurements; nasal
      > cavity; nasal mucosa; lung comliance; pulmonary ventilation;
      > respiratory function tests; trachea; vagus nerve
      >
      > The key role of the nose is to adjust the air flow and nasal
      > resistance (1). Nasal resistance is the crucial element in achieving
      > optimal alveolar ventilation for the respiratory work performed.
      > Studies on the air flow have shown a nearly constant volume flow in
      > particular segments and almost exclusive presence of laminar movement
      > (regardless of the air flow rate) along the surface of nasal mucosa.
      > The flow mostly proceeds through the middle and inferior part of the
      > nose, i.e. the region of middle nasal meatus and inferiorly between
      > inferior nasal concha and septum (2). The nasal cavity lacks
      > flexibility, except in the segment bordering with the maxillary
      > sinuses in the part of middle nasal meatus. There are two spaces
      > covered by mucosa, termed by Zuckerkandel as inferior and posterior
      > nasal fontanel (3). The nonmyelinated cholinergic endings (C-fibers)
      > conduct the stimulus caused by mechanical, chemical and thermal
      > irritants and are the only receptors that have been histologically
      > verified in nasal mucosa. Since they are stimulated by negative
      > pressure, they also function as flow receptors (4,5). Fibers from the
      > nasal mucosa constitute the parts of the first (ophthalmic) and second
      > (maxillary) branches of the trigeminal nerve. They are somatotopically
      > organized and grouped in the Gasserian ganglion and the principal
      > sensory nucleus and spinal trigeminal nucleus (6). A relationship
      > between the trigeminal nerve stimulation and vagal ambiguus nucleus
      > suggests that trigeminal stimulation modifies the neuronal firing
      > pattern and consequently causes changes in the vagal outflow (7).
      > Results of a number of animal experiments have demonstrated that
      > changes in the pulmonary resistance occurring during nasal mucosa
      > stimulation, are eliminated by resection of the ethmoidal nerve or
      > vagal nerve (8). This clearly points to the existence of nerve reflex,
      > but its characteristics, afferent part origin, nature of physiologic
      > stimulation, time of reflex exhaustion, compensatory mechanisms, and
      > pattern of efferent function have not yet been clarified. According to
      > our hypothesis, the region of the afferent part of the reflex in the
      > nose is the one which meets the following conditions: (a) flow of air
      > at a certain rate through a segment of the nose, whereby the amount
      > and rate are constant for certain states of the body (rest, exercise),
      > whereas the rate of air flow through this segment should substantially
      > differ from the flow rate through other segments of the nose; and (b)
      > the structures stimulated on inspiration (negative pressure,
      > Bernoulli's effect) and expiration (positive pressure) should be
      > elastic and free in space to allow the highest possible amplitude,
      > i.e., a free range of possible amplitudes.
      > The only part of the nose which meets both these criteria is the
      > region in the middle nasal meatus known as the inferior and posterior
      > nasal fontanels. They are made of a network of fibers continuing to
      > the periosteum. Above this network there is a tissue rich in cavernous
      > spaces abundant in nonmyelinated nervous endings on both sides. These
      > structures are bilaterally superimposed by a layer of respiratory
      > epithelium. The average infero-superior length of the anterior
      > fontanel is approximately 11 mm and the anterior-posterior one
      > approximatly 18 mm. Regarding the posterior fontanel, inferio-superior
      > length is approximately 11 mm and antero-posterior one approximately
      > 17 mm (9).
      > The "father" of modern nasal endoscopy, Professor Messerklinger,
      > noticed movements in the nasal fontanels: I have seen slight inward
      > and outward movements of healthy fontanels with forced nasal breathing
      > (3).
      > In this study, we tried to cause maximal receptor stimulation by light
      > mechanical tactile stimulation of ethmoidal nerves which are connected
      > with second-order low threshold mechanoreceptive neurons (10) and to
      > compare stimulation and anesthesia of the two regions of the nose.
      > Induced stimulation was assumed to result in the maximal response of
      > the vagus tone, i.e., smooth muscle of the tracheobronchial tree, with
      > resulting changes in spirometric and body plethysmographic parameters.
      > We wanted to confirm the trigeminus-mediated effect on the vagus
      > parasympathetic tone of tracheal and bronchial smooth muscle, and to
      > try and proof the nerve endings � receptors in the nasal cavity mucosa
      > of the nasal fontanels.
      > Subjects and Methods
      > Thirty healthy volunteers, non-smokers, 15 women and 15 men, aged
      > 14-61 years, with no chronic diseases in their rhinologic and
      > pulmologic history and no data on acute rhinologic or pulmologic
      > disease during the month preceding the study, were randomly divided
      > into three groups. Group 1 included ten subjects, five women and five
      > men, aged 18-56 years, mean age 31.8 years. Group 2 consisted of ten
      > subjects, five women and five men, aged 18-58 years, mean age 31.3
      > years. Control group included ten subjects, five women and five men
      > aged 18-61 years, mean age 32.1 years. There was no significant
      > difference in age, body height and weight between the three groups
      > In the group 1, a cotton pledge soaked in saline was inserted in the
      > middle nasal meatus on both sides. In the group 2, a cotton pledge
      > soaked in 0.5 ml of 5% cocaine solution was inserted in the middle
      > nasal meatus on both sides. In the control group a saline-soaked
      > cotton pledge was bilaterally inserted between inferior nasal concha
      > and septum, up to the upper level of the concha. The air flow through
      > this part is equal to that through the middle nasal meatus (11), but
      > is characterized by the presence of the reflex origin influencing
      > cardiac action via the vagus nerve (12).
      > The cotton pledge inserted was large enough to adhere to the mucosa,
      > producing light mechanical stimulation without dropping out
      > spontaneously, and without producing discomfort. The pledge was well
      > squeezed out before insertion, to avoid undesirable stimulation or
      > anesthesia of other parts of the nasal mucosa. The first measurement
      > after 15 minute-delay offered the elimination of any pain-caused
      > changes due to insertion of the pledge.
      > The parameters of lung ventilation were assessed by body
      > plethysmography on a Bodyscreen II (Dr�ger GmbH, L�beck, Germany). All
      > parameters were measured three times: one minute before, and 15 and 60
      > minutes after the insertion of cotton pledges. Mean values were used
      > for statistical evaluation. The parameters measured were: forced
      > expiratory flow in the first second (FEV1), peek expiratory flow (PEF)
      > and total resistance (Rt). These parameters are commonly used in the
      > evaluation of the obstructive character of the tracheobronchial tree
      > pathology.
      > The study was approved by the hospital ethics committee, and an
      > informed consent was obtained from all subjects.
      > Data analysis was done using SPSS PC 3.0 software ( SPSS inc.,
      > Chicago, Ill, USA). Normal distribution was tested by
      > Kolmogorov-Smirnov nonparametric test. As all results showed normal
      > distribution, they were tested by two-tailed paired Student's t test.
      > Results
      > Mean values of measured parameters before, and 15 and 60 minutes after
      > the insertion of cotton pledges are shown in Table 1.
      > Table 1: Respiratory parameters (mean�SD) in the normal subjects in
      > whom a cotton pledge soaked in saline was inserted in the middle nasal
      > meatus on both sides (group 1); those in whom a cotton pledge soaked
      > in 0.5 mL of 5% cocaine solution was inserted in the middle nasal
      > meatus on both sides (group 2); and control group with a saline-soaked
      > cotton pledge bilaterally inserted between inferior nasal concha and
      > septum, up to the upper level of the concha [view this table]
      >
      > Group 1
      > A statistically significant decrease between the breathing parameters
      > measured before and 15 min after the saline-soaked pledge insertion
      > was observed for FEV1 (p=0.01) and statistically significant increase
      > for Rt (p=0.03). After 60 min, a statistically significant decrease
      > from the initial value was found for PEF (p=0.01) and an increase for
      > Rt (p=0.048).
      > Group 2
      > There was no statistically significant difference between the values
      > of the breathing parameter measured before and 15 or 60 min after the
      > insertion of cotton pledge soaked in 5% cocaine.
      > Control group
      > With the insertion of a saline-soaked cotton pledge between inferior
      > nasal concha and septum, a statistically significant decrease was
      > observed between the FEV1 values measured before and 15 min after the
      > pledge insertion (p=0.04), but not 60 min after the insertion of the
      > pledge.
      >
      > ** Discussion
      > The starting hypothesis of the study was the existence of a reflex arc
      > between the nasal mucosa and smooth muscles of the tracheobronchial
      > tree. There is a reflex, named nasopulmonary reflex, which causes
      > bronchoconstriction in humans after the stimulation of the nasal
      > mucosa by cold air (13,14). This bronchoconstriction in animals can be
      > prevented by the resection of the ethmoidal or vagal nerve (8).
      > It is well known that the area innervated by the trigeminal nerve is a
      > potent reflexogenic area (diving reflex, corneal reflex, sneezing).
      > The physiology of these reflexes is based on the more or less painful
      > stimuli (mechanical or chemical irritants and low temperature). The
      > most potent of them regarding the influence upon the vagal tone is the
      > diving reflex. It is a protective reflex against drowning and is
      > induced by immersion of the face in ice water or by cooling of the
      > face or forehead (15). Bilateral application of cold stimulus to the
      > individual divisions of the trigeminal nerve showed that the
      > ophthalmic division was the most sensitive pathway for this reflex
      > (16). The nasal cavity is mostly innervated by maxillary division of
      > trigeminal nerve and therefore diving reflex is not engaged in normal
      > reflex physiology connected with the nose. It is also known that the
      > stimulation to the trigeminal branches may cause cardiac arrhythmia,
      > arrest, and changes in the blood pressure (12,17). These reflexes may
      > potentially be more harmful than beneficial to the man, therefore the
      > body must have some regulatory mechanisms to control the reflex
      > duration. This, however, makes research aimed at their exact
      > description quite difficult.
      > The model of light mechanical (permanent tactile) stimulation of the
      > region was chosen in order to achieve the strongest possible reflex
      > response from the presumed ethmoidal nerve fibers connected with low
      > threshold mechanoreceptive second-order neurons in the trigeminal
      > nuclei. These neurons receive only light tactile input and are not
      > responding to noxious chemical or mechanical stimuli applied to the
      > nasal cavity. These neurons were found in animal studies (10), and it
      > can be presumed that they also exist in humans.
      > Light mechanical stimulation used in our study closely resembles the
      > physiologic stimulation from air stream and could be considered a
      > modified physiologic stimulation best stimulating nerves within the
      > nasal cavity occurring during air flow in physiologic conditions. In
      > the control group, the same postulates were employed, and the target
      > for the stimulation was the mucosal region between inferior nasal
      > concha and septum which, unlike the middle nasal meatus, has the
      > characteristics of the nasocardial reflex arc structure and origin (12).
      > Tracheal and bronchial smooth muscles are innervated by
      > parasympathetic innervation via the vagus nerve, which can change
      > their tone and airway diameter (18). The changes occurring in the
      > tracheaobronchial tree and lungs due to the increased parasympathetic,
      > i.e., vagus tone, must therefore entail changes in the spirometric and
      > plethysmographic parameters measuring the airway flow and resistance
      > (FEV1, Rt).
      > Saline-soaked cotton pledge inserted in the region of the middle nasal
      > meatus, elicited significant changes of respiration parameters 15
      > minutes after stimulation, pointing to alterations in the width of the
      > major and medium intrapulmonary airways, i.e., increased Rt with
      > decreased FEV1. At 1 hour, a statistically significant difference was
      > found in the values of the parameters of PEF and Rt, which are
      > characteristic of alterations in major and medium intrapulmonary
      > airways (19) but may also suggest a gradual reflex exhaustion.
      > In the subjects in whom the region of the middle nasal meatus was
      > obstructed by a cotton pledge soaked in 5% cocaine solution, no
      > statistically significant changes in the respiratory parameters were
      > recorded either at 15 or at 60 minutes. This was the caused by the
      > exclusion of regular nerve firing from the region of the middle nasal
      > meatus, and anterior and posterior nasal fontanel caused by nerve
      > ending anesthesia by 5% cocaine solution.
      > With the cocaine anesthesia of the region, the afferent part of the
      > arc maintained the parasympathetic (vagus) nerve tone at the basal
      > values, despite the middle nasal meatus mechanical stimulation.
      > Recanalization of the complete air flow through the region of the
      > middle nasal meatus, caused by the obstruction of the part of the nose
      > between inferior nasal concha and septum, in the second group,
      > produced a mild increase of trigeminal nerve stimulation. That changed
      > the parasympathetic (vagal) tone as well as the airway diameter trough
      > its action on the smooth muscles of the lungs and tracheobronchial tree.
      > This indicates that a continuous physiologic stimulus maintains the
      > vagal function at a certain, constant level already known as resting
      > vagal tone (20,21). Changes in the stimulus intensity entail changes
      > in the function of tracheobronchial smooth muscle tone and airway
      > diameter trough the increased vagal tone.
      > References
      > 1 Knops JL, McCaffrey TV, Kern EB. Physiology. Clinical application.
      > Clinics of North America 1993;26: 517-34.
      > 2 Hahn I, Scherer PW, Mozell MM. Velocity profiles measured for
      > airflow through a large-scale model of the human nasal cavity. J Appl
      > Physiol 1993;75: 2237-87.
      > 3 Messerklinger W. Endoscopy of the nose., Baltimore-Munich: Urban &
      > Schwarzenberg; 1978.
      > 4 Tsubone H. Nasal "pressure" receptors. Nippon Juigaku Zasshi
      > 1990;52:225-32.
      > 5 Tsubone H. Nasal flow receptors of the rat. Resp Physiol
      1989;75:51-64.
      > 6 Walois F, Larnicol N, Rose D, Duron B. A comparative HRP study of
      > the neuronal supply to the inferior and superior nasal meatus in the
      > cat. Neurosci Lett 1992;139:234-8.
      > 7 Komatsubara J. Effects of trigeminal stimulation on the vagal
      > ambiguus neurons. Kanagawa-Shigaku 1989;23:598-609.
      > 8 Whicker JH, Kern EB, Hyatt R. Nasopulmonary reflex: Evaluation in
      > the nonparalyzed and paralysed anaesthetized dog. Annals of
      > Otolaryngology 1978; 87:91-8.
      > 9 Isobe M, Murakami G, Kataura A. Variations of the uncinate process
      > of the lateral nasal wall with clinical implications. Clin Anatomy
      > 1998;11:295-303.
      > 10 Lucier GE, Egizii R. Characterization of cat nasal afferents and
      > brain stem neurons receiving ethmoidal input. Exp Neurol 1989;103:83-9.
      > 11 Baraniuk JN, Kaliner M. Neuropeptides and nasal secretion. AM J
      > Physiol 1991;261:223-35.
      > 12 Betlejewski S, Burduk D. Der nasokardiale reflex.
      > Otorhinolaryngologia Nova 1995;5:91-4.
      > 13 �ercer A. Investigations sur l' influence reflectoire de la cavite
      > nasale surt le poumon du meme cote. Acta Otolaryngol (Stockh)
      1930;14:82.
      > 14 �ercer A. Nos i dihanje. Radovi JAZU 1935;251:1-38.
      > 15 Allen MT, Shelley KS, Boquet AJ Jr. A comparison of cardiovascular
      > and autonomic adjustments to three types of cold stimulation tasks.
      > Int J Psychophysiol 1992;13:59-69.
      > 16 Khurana RK, Watabiki S, Hebel JR, Toro R, Nelson E.. Cold face test
      > in the assessment of trigeminal- brainstem-vagal function in humans.
      > Ann Neurol 1980;7:144-9.
      > 17 Allison DJ. Dangerous reflexes from the nose. Lancet (letter)
      > 1977;1:909.
      > 18 Barnes PJ. Neural control of human airways in health and disease.
      > Am Rev Respir Dis 1986;134:1289-314.
      > 19 �u�kin E. Testovi plucnih funkcija. In: Gamulin S, Maru�i� M,
      > Krvavica S, editors. 3rd ed. Zagreb: Medicinska naklada; 1995. p. 656-9.
      > 20 Olsen CR, Colesbarth HJH, Mebel P, Nadel JA, Staub NC. Motor
      > control of pulmonary airways studied by nerve stimulation. J Appl
      > Physiol 1965;20:202-8.
      > 21 de Troyer A, Yernault J-C, Rodenstein D. Effect of vagal blockade
      > on lung mechanics in normal man. J Appl Physiol 1979;46:217-26.
      >
      > Recieved: March 23, 1998
      > Accepted: June 16, 1998
      >
      > Correspondence to:
      > Damir Mili�i�
      > Department of Otorhinolaryngology and Cevicofacial Surgery
      > Dr. Josip Ben�evi� General Hospital
      > Andrije �tampara 42
      > 35000 Slavonski Brod, Croatia
      > opbolsb@...
      >
      > crta.gif (62 bytes)
      > Copyright � 1997 by the Croatian Medical Journal. All rights reserved.
      > Created 20/1/99 - Last Modified 20/1/99
      > Created and maintained by: Tinman
      >
    • Marc Verhaegen
      ... I guess so: in humans it s part of the ethmoid bone; uncinatus means hooked . ... The morphology of the UP & nasal fontanelle is described in 119 human
      Message 2 of 7 , Nov 9, 2007
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        Op 09-11-2007 02:07, DDeden <alas_my_loves@...> schreef:

        > Marc, is the nasal uncinate process an entirely different structure
        > than the uncinate process in birds and manicopteran dinos?

        I guess so: in humans it's part of the ethmoid bone; "uncinatus" means
        "hooked".

        > They are
        > both significant in respiration rhythm and possibly breath holding
        > AFAICT. (The nasopulmonary reflex relates to sneezing and MDR).
        >
        > 9 Isobe M, Murakami G, Kataura A. Variations of the uncinate process
        > of the lateral nasal wall with clinical implications. Clin Anatomy
        > 1998;11:295-303.

        The morphology of the UP & nasal fontanelle is described in 119 human
        specimens, which were examined both before & after removal of the mucosa.
        Forms of the UP are classified & based on which site the process is
        articulated, and each form is characterized in relation to the endonasal
        endoscopic operative technique.
        - Type I: The infero-posterior tip of the UP is articulated to the inferior
        concha (turbinate). This was the most frequently observed type.
        - Subtype I-b: The UP adhered to the inferior concha along the
        antero-inferior margin. The anterior nasal fontanelle was closed by the UP
        adhesion; therefore, special attention is required not to damage the
        lacrimal bone.
        - Type N: The tip of the UP had no articulation and made a free edge. It
        reduces the bony resistance at surgery.
        - Type S: The tip articulated to the superior structures, such as the bulla
        ethmoid, medial orbital wall, tegument of the maxillary sinus & basal area
        of the ethmoid sinus. These structures are known as high-risk areas of
        endonasal surgery (Levine 1993).
        - Type P: The tip articulated with the perpendicular plate of the palatine
        bone. The UP was prolonged posteriorly. Attention should be paid to the
        sphenopalatine artery, which goes through the posterior edge of the middle
        concha.
        4 additional variations (combinations of the above basic types, Variations
        IS, IP, SP & ISP) were also observed.
        ______

        >
        > --- In AAT@yahoogroups.com, "DDeden" <alas_my_loves@...> wrote:
        >>
        >> Very interesting article by Croatian Medical Journal, connects stimuli
        >> of inferior conchae to bronchial closure and HR decrease (MDR).
        >>
        >> See ** 1/2 way down for specific connections, if in hurry.
        >>
        >> December 1998 (Volume 39, Number 4)
        >> Influence of Nasal Fontanel Receptors on the Regulation of
        >> Tracheobronchal Vagal Tone
        >> Damir Mili�i�, Ranko Mladina1, Davorin �ani�, Drago Prgomet, Dinko
        > Leovi�
        >> Department of Otorhinolaryngology and Cervicofacial Surgery, Dr. Josip
        >> Ben�evi� General Hospital, Slavonski Brod; and 1Department of
        >> Otorhinolaryngology, University Hospital Center Zagreb, Zagreb, Croatia
        >>
        >> Aim. To test the hypothesis according that the receptors located in
        >> the nasal fontanels influence the regulation of the tracheobronchial
        >> tree vagus tone.
        >> Methods. Changes in respiratory parameters (forced expiratory volume
        >> in the first second- FEV1 and total resistance- Rt) occurring
        >> consequentially to light mechanical nasal stimulation were determined
        >> in healthy volunteer, non-smokers using spirometric and body
        >> plethysmographic measurements. The parameters were measured before and
        >> at 15 and 60 min after mechanical stimulation with cotton pledge.
        >> Results. In subjects in whom the middle nasal meatus was stimulated by
        >> a cotton pledge soaked in saline, FEV1 decreased (p=0.01) and Rt
        >> increased (p=0.03). In subjects in whom the middle nasal meatus was
        >> stimulated by a cotton pledge soaked in 5% cocaine solution, no change
        >> was observed. In the control group of subjects, in whom the inferior
        >> nasal concha was stimulated by a cotton pledge soaked in saline, only
        >> a statistically significant decrease for FEV1 (p=0.04) was found.
        >> Conclusion. There is a reflex communication between the nasal fontanel
        >> receptors and lungs, which is regulating the tracheobronchial vagal
        >> tone and resistance in lung airways. Further studies of this important
        >> physiologic relation are needed.
        >>
        >> Key words: bronchoconstriction; lung volume measurements; nasal
        >> cavity; nasal mucosa; lung comliance; pulmonary ventilation;
        >> respiratory function tests; trachea; vagus nerve
        >>
        >> The key role of the nose is to adjust the air flow and nasal
        >> resistance (1). Nasal resistance is the crucial element in achieving
        >> optimal alveolar ventilation for the respiratory work performed.
        >> Studies on the air flow have shown a nearly constant volume flow in
        >> particular segments and almost exclusive presence of laminar movement
        >> (regardless of the air flow rate) along the surface of nasal mucosa.
        >> The flow mostly proceeds through the middle and inferior part of the
        >> nose, i.e. the region of middle nasal meatus and inferiorly between
        >> inferior nasal concha and septum (2). The nasal cavity lacks
        >> flexibility, except in the segment bordering with the maxillary
        >> sinuses in the part of middle nasal meatus. There are two spaces
        >> covered by mucosa, termed by Zuckerkandel as inferior and posterior
        >> nasal fontanel (3). The nonmyelinated cholinergic endings (C-fibers)
        >> conduct the stimulus caused by mechanical, chemical and thermal
        >> irritants and are the only receptors that have been histologically
        >> verified in nasal mucosa. Since they are stimulated by negative
        >> pressure, they also function as flow receptors (4,5). Fibers from the
        >> nasal mucosa constitute the parts of the first (ophthalmic) and second
        >> (maxillary) branches of the trigeminal nerve. They are somatotopically
        >> organized and grouped in the Gasserian ganglion and the principal
        >> sensory nucleus and spinal trigeminal nucleus (6). A relationship
        >> between the trigeminal nerve stimulation and vagal ambiguus nucleus
        >> suggests that trigeminal stimulation modifies the neuronal firing
        >> pattern and consequently causes changes in the vagal outflow (7).
        >> Results of a number of animal experiments have demonstrated that
        >> changes in the pulmonary resistance occurring during nasal mucosa
        >> stimulation, are eliminated by resection of the ethmoidal nerve or
        >> vagal nerve (8). This clearly points to the existence of nerve reflex,
        >> but its characteristics, afferent part origin, nature of physiologic
        >> stimulation, time of reflex exhaustion, compensatory mechanisms, and
        >> pattern of efferent function have not yet been clarified. According to
        >> our hypothesis, the region of the afferent part of the reflex in the
        >> nose is the one which meets the following conditions: (a) flow of air
        >> at a certain rate through a segment of the nose, whereby the amount
        >> and rate are constant for certain states of the body (rest, exercise),
        >> whereas the rate of air flow through this segment should substantially
        >> differ from the flow rate through other segments of the nose; and (b)
        >> the structures stimulated on inspiration (negative pressure,
        >> Bernoulli's effect) and expiration (positive pressure) should be
        >> elastic and free in space to allow the highest possible amplitude,
        >> i.e., a free range of possible amplitudes.
        >> The only part of the nose which meets both these criteria is the
        >> region in the middle nasal meatus known as the inferior and posterior
        >> nasal fontanels. They are made of a network of fibers continuing to
        >> the periosteum. Above this network there is a tissue rich in cavernous
        >> spaces abundant in nonmyelinated nervous endings on both sides. These
        >> structures are bilaterally superimposed by a layer of respiratory
        >> epithelium. The average infero-superior length of the anterior
        >> fontanel is approximately 11 mm and the anterior-posterior one
        >> approximatly 18 mm. Regarding the posterior fontanel, inferio-superior
        >> length is approximately 11 mm and antero-posterior one approximately
        >> 17 mm (9).
        >> The "father" of modern nasal endoscopy, Professor Messerklinger,
        >> noticed movements in the nasal fontanels: I have seen slight inward
        >> and outward movements of healthy fontanels with forced nasal breathing
        >> (3).
        >> In this study, we tried to cause maximal receptor stimulation by light
        >> mechanical tactile stimulation of ethmoidal nerves which are connected
        >> with second-order low threshold mechanoreceptive neurons (10) and to
        >> compare stimulation and anesthesia of the two regions of the nose.
        >> Induced stimulation was assumed to result in the maximal response of
        >> the vagus tone, i.e., smooth muscle of the tracheobronchial tree, with
        >> resulting changes in spirometric and body plethysmographic parameters.
        >> We wanted to confirm the trigeminus-mediated effect on the vagus
        >> parasympathetic tone of tracheal and bronchial smooth muscle, and to
        >> try and proof the nerve endings � receptors in the nasal cavity mucosa
        >> of the nasal fontanels.
        >> Subjects and Methods
        >> Thirty healthy volunteers, non-smokers, 15 women and 15 men, aged
        >> 14-61 years, with no chronic diseases in their rhinologic and
        >> pulmologic history and no data on acute rhinologic or pulmologic
        >> disease during the month preceding the study, were randomly divided
        >> into three groups. Group 1 included ten subjects, five women and five
        >> men, aged 18-56 years, mean age 31.8 years. Group 2 consisted of ten
        >> subjects, five women and five men, aged 18-58 years, mean age 31.3
        >> years. Control group included ten subjects, five women and five men
        >> aged 18-61 years, mean age 32.1 years. There was no significant
        >> difference in age, body height and weight between the three groups
        >> In the group 1, a cotton pledge soaked in saline was inserted in the
        >> middle nasal meatus on both sides. In the group 2, a cotton pledge
        >> soaked in 0.5 ml of 5% cocaine solution was inserted in the middle
        >> nasal meatus on both sides. In the control group a saline-soaked
        >> cotton pledge was bilaterally inserted between inferior nasal concha
        >> and septum, up to the upper level of the concha. The air flow through
        >> this part is equal to that through the middle nasal meatus (11), but
        >> is characterized by the presence of the reflex origin influencing
        >> cardiac action via the vagus nerve (12).
        >> The cotton pledge inserted was large enough to adhere to the mucosa,
        >> producing light mechanical stimulation without dropping out
        >> spontaneously, and without producing discomfort. The pledge was well
        >> squeezed out before insertion, to avoid undesirable stimulation or
        >> anesthesia of other parts of the nasal mucosa. The first measurement
        >> after 15 minute-delay offered the elimination of any pain-caused
        >> changes due to insertion of the pledge.
        >> The parameters of lung ventilation were assessed by body
        >> plethysmography on a Bodyscreen II (Dr�ger GmbH, L�beck, Germany). All
        >> parameters were measured three times: one minute before, and 15 and 60
        >> minutes after the insertion of cotton pledges. Mean values were used
        >> for statistical evaluation. The parameters measured were: forced
        >> expiratory flow in the first second (FEV1), peek expiratory flow (PEF)
        >> and total resistance (Rt). These parameters are commonly used in the
        >> evaluation of the obstructive character of the tracheobronchial tree
        >> pathology.
        >> The study was approved by the hospital ethics committee, and an
        >> informed consent was obtained from all subjects.
        >> Data analysis was done using SPSS PC 3.0 software ( SPSS inc.,
        >> Chicago, Ill, USA). Normal distribution was tested by
        >> Kolmogorov-Smirnov nonparametric test. As all results showed normal
        >> distribution, they were tested by two-tailed paired Student's t test.
        >> Results
        >> Mean values of measured parameters before, and 15 and 60 minutes after
        >> the insertion of cotton pledges are shown in Table 1.
        >> Table 1: Respiratory parameters (mean�SD) in the normal subjects in
        >> whom a cotton pledge soaked in saline was inserted in the middle nasal
        >> meatus on both sides (group 1); those in whom a cotton pledge soaked
        >> in 0.5 mL of 5% cocaine solution was inserted in the middle nasal
        >> meatus on both sides (group 2); and control group with a saline-soaked
        >> cotton pledge bilaterally inserted between inferior nasal concha and
        >> septum, up to the upper level of the concha [view this table]
        >>
        >> Group 1
        >> A statistically significant decrease between the breathing parameters
        >> measured before and 15 min after the saline-soaked pledge insertion
        >> was observed for FEV1 (p=0.01) and statistically significant increase
        >> for Rt (p=0.03). After 60 min, a statistically significant decrease
        >> from the initial value was found for PEF (p=0.01) and an increase for
        >> Rt (p=0.048).
        >> Group 2
        >> There was no statistically significant difference between the values
        >> of the breathing parameter measured before and 15 or 60 min after the
        >> insertion of cotton pledge soaked in 5% cocaine.
        >> Control group
        >> With the insertion of a saline-soaked cotton pledge between inferior
        >> nasal concha and septum, a statistically significant decrease was
        >> observed between the FEV1 values measured before and 15 min after the
        >> pledge insertion (p=0.04), but not 60 min after the insertion of the
        >> pledge.
        >>
        >> ** Discussion
        >> The starting hypothesis of the study was the existence of a reflex arc
        >> between the nasal mucosa and smooth muscles of the tracheobronchial
        >> tree. There is a reflex, named nasopulmonary reflex, which causes
        >> bronchoconstriction in humans after the stimulation of the nasal
        >> mucosa by cold air (13,14). This bronchoconstriction in animals can be
        >> prevented by the resection of the ethmoidal or vagal nerve (8).
        >> It is well known that the area innervated by the trigeminal nerve is a
        >> potent reflexogenic area (diving reflex, corneal reflex, sneezing).
        >> The physiology of these reflexes is based on the more or less painful
        >> stimuli (mechanical or chemical irritants and low temperature). The
        >> most potent of them regarding the influence upon the vagal tone is the
        >> diving reflex. It is a protective reflex against drowning and is
        >> induced by immersion of the face in ice water or by cooling of the
        >> face or forehead (15). Bilateral application of cold stimulus to the
        >> individual divisions of the trigeminal nerve showed that the
        >> ophthalmic division was the most sensitive pathway for this reflex
        >> (16). The nasal cavity is mostly innervated by maxillary division of
        >> trigeminal nerve and therefore diving reflex is not engaged in normal
        >> reflex physiology connected with the nose. It is also known that the
        >> stimulation to the trigeminal branches may cause cardiac arrhythmia,
        >> arrest, and changes in the blood pressure (12,17). These reflexes may
        >> potentially be more harmful than beneficial to the man, therefore the
        >> body must have some regulatory mechanisms to control the reflex
        >> duration. This, however, makes research aimed at their exact
        >> description quite difficult.
        >> The model of light mechanical (permanent tactile) stimulation of the
        >> region was chosen in order to achieve the strongest possible reflex
        >> response from the presumed ethmoidal nerve fibers connected with low
        >> threshold mechanoreceptive second-order neurons in the trigeminal
        >> nuclei. These neurons receive only light tactile input and are not
        >> responding to noxious chemical or mechanical stimuli applied to the
        >> nasal cavity. These neurons were found in animal studies (10), and it
        >> can be presumed that they also exist in humans.
        >> Light mechanical stimulation used in our study closely resembles the
        >> physiologic stimulation from air stream and could be considered a
        >> modified physiologic stimulation best stimulating nerves within the
        >> nasal cavity occurring during air flow in physiologic conditions. In
        >> the control group, the same postulates were employed, and the target
        >> for the stimulation was the mucosal region between inferior nasal
        >> concha and septum which, unlike the middle nasal meatus, has the
        >> characteristics of the nasocardial reflex arc structure and origin (12).
        >> Tracheal and bronchial smooth muscles are innervated by
        >> parasympathetic innervation via the vagus nerve, which can change
        >> their tone and airway diameter (18). The changes occurring in the
        >> tracheaobronchial tree and lungs due to the increased parasympathetic,
        >> i.e., vagus tone, must therefore entail changes in the spirometric and
        >> plethysmographic parameters measuring the airway flow and resistance
        >> (FEV1, Rt).
        >> Saline-soaked cotton pledge inserted in the region of the middle nasal
        >> meatus, elicited significant changes of respiration parameters 15
        >> minutes after stimulation, pointing to alterations in the width of the
        >> major and medium intrapulmonary airways, i.e., increased Rt with
        >> decreased FEV1. At 1 hour, a statistically significant difference was
        >> found in the values of the parameters of PEF and Rt, which are
        >> characteristic of alterations in major and medium intrapulmonary
        >> airways (19) but may also suggest a gradual reflex exhaustion.
        >> In the subjects in whom the region of the middle nasal meatus was
        >> obstructed by a cotton pledge soaked in 5% cocaine solution, no
        >> statistically significant changes in the respiratory parameters were
        >> recorded either at 15 or at 60 minutes. This was the caused by the
        >> exclusion of regular nerve firing from the region of the middle nasal
        >> meatus, and anterior and posterior nasal fontanel caused by nerve
        >> ending anesthesia by 5% cocaine solution.
        >> With the cocaine anesthesia of the region, the afferent part of the
        >> arc maintained the parasympathetic (vagus) nerve tone at the basal
        >> values, despite the middle nasal meatus mechanical stimulation.
        >> Recanalization of the complete air flow through the region of the
        >> middle nasal meatus, caused by the obstruction of the part of the nose
        >> between inferior nasal concha and septum, in the second group,
        >> produced a mild increase of trigeminal nerve stimulation. That changed
        >> the parasympathetic (vagal) tone as well as the airway diameter trough
        >> its action on the smooth muscles of the lungs and tracheobronchial tree.
        >> This indicates that a continuous physiologic stimulus maintains the
        >> vagal function at a certain, constant level already known as resting
        >> vagal tone (20,21). Changes in the stimulus intensity entail changes
        >> in the function of tracheobronchial smooth muscle tone and airway
        >> diameter trough the increased vagal tone.
        >> References
        >> 1 Knops JL, McCaffrey TV, Kern EB. Physiology. Clinical application.
        >> Clinics of North America 1993;26: 517-34.
        >> 2 Hahn I, Scherer PW, Mozell MM. Velocity profiles measured for
        >> airflow through a large-scale model of the human nasal cavity. J Appl
        >> Physiol 1993;75: 2237-87.
        >> 3 Messerklinger W. Endoscopy of the nose., Baltimore-Munich: Urban &
        >> Schwarzenberg; 1978.
        >> 4 Tsubone H. Nasal "pressure" receptors. Nippon Juigaku Zasshi
        >> 1990;52:225-32.
        >> 5 Tsubone H. Nasal flow receptors of the rat. Resp Physiol
        > 1989;75:51-64.
        >> 6 Walois F, Larnicol N, Rose D, Duron B. A comparative HRP study of
        >> the neuronal supply to the inferior and superior nasal meatus in the
        >> cat. Neurosci Lett 1992;139:234-8.
        >> 7 Komatsubara J. Effects of trigeminal stimulation on the vagal
        >> ambiguus neurons. Kanagawa-Shigaku 1989;23:598-609.
        >> 8 Whicker JH, Kern EB, Hyatt R. Nasopulmonary reflex: Evaluation in
        >> the nonparalyzed and paralysed anaesthetized dog. Annals of
        >> Otolaryngology 1978; 87:91-8.
        >> 9 Isobe M, Murakami G, Kataura A. Variations of the uncinate process
        >> of the lateral nasal wall with clinical implications. Clin Anatomy
        >> 1998;11:295-303.
        >> 10 Lucier GE, Egizii R. Characterization of cat nasal afferents and
        >> brain stem neurons receiving ethmoidal input. Exp Neurol 1989;103:83-9.
        >> 11 Baraniuk JN, Kaliner M. Neuropeptides and nasal secretion. AM J
        >> Physiol 1991;261:223-35.
        >> 12 Betlejewski S, Burduk D. Der nasokardiale reflex.
        >> Otorhinolaryngologia Nova 1995;5:91-4.
        >> 13 �ercer A. Investigations sur l' influence reflectoire de la cavite
        >> nasale surt le poumon du meme cote. Acta Otolaryngol (Stockh)
        > 1930;14:82.
        >> 14 �ercer A. Nos i dihanje. Radovi JAZU 1935;251:1-38.
        >> 15 Allen MT, Shelley KS, Boquet AJ Jr. A comparison of cardiovascular
        >> and autonomic adjustments to three types of cold stimulation tasks.
        >> Int J Psychophysiol 1992;13:59-69.
        >> 16 Khurana RK, Watabiki S, Hebel JR, Toro R, Nelson E.. Cold face test
        >> in the assessment of trigeminal- brainstem-vagal function in humans.
        >> Ann Neurol 1980;7:144-9.
        >> 17 Allison DJ. Dangerous reflexes from the nose. Lancet (letter)
        >> 1977;1:909.
        >> 18 Barnes PJ. Neural control of human airways in health and disease.
        >> Am Rev Respir Dis 1986;134:1289-314.
        >> 19 �u�kin E. Testovi plucnih funkcija. In: Gamulin S, Maru�i� M,
        >> Krvavica S, editors. 3rd ed. Zagreb: Medicinska naklada; 1995. p. 656-9.
        >> 20 Olsen CR, Colesbarth HJH, Mebel P, Nadel JA, Staub NC. Motor
        >> control of pulmonary airways studied by nerve stimulation. J Appl
        >> Physiol 1965;20:202-8.
        >> 21 de Troyer A, Yernault J-C, Rodenstein D. Effect of vagal blockade
        >> on lung mechanics in normal man. J Appl Physiol 1979;46:217-26.
        >>
        >> Recieved: March 23, 1998
        >> Accepted: June 16, 1998
        >>
        >> Correspondence to:
        >> Damir Mili�i�
        >> Department of Otorhinolaryngology and Cevicofacial Surgery
        >> Dr. Josip Ben�evi� General Hospital
        >> Andrije �tampara 42
        >> 35000 Slavonski Brod, Croatia
        >> opbolsb@...
        >>
        >> crta.gif (62 bytes)
        >> Copyright � 1997 by the Croatian Medical Journal. All rights reserved.
        >> Created 20/1/99 - Last Modified 20/1/99
        >> Created and maintained by: Tinman
        >>
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      • DDeden
        Thanks Marc, interesting, variable in modern humans, not impossibly showing some genetic differences in tropical vs temperate or humid vs arid evolutionary
        Message 3 of 7 , Nov 9, 2007
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          Thanks Marc, interesting, variable in modern humans, not impossibly
          showing some genetic differences in tropical vs temperate or humid vs
          arid evolutionary selection, or relationship to breath holding and
          gasp reflex. DD

          --- In AAT@yahoogroups.com, Marc Verhaegen <marc.verhaegen@...> wrote:
          >
          > Op 09-11-2007 02:07, DDeden <alas_my_loves@...> schreef:
          >
          > > Marc, is the nasal uncinate process an entirely different structure
          > > than the uncinate process in birds and manicopteran dinos?
          >
          > I guess so: in humans it's part of the ethmoid bone; "uncinatus" means
          > "hooked".
          >
          > > They are
          > > both significant in respiration rhythm and possibly breath holding
          > > AFAICT. (The nasopulmonary reflex relates to sneezing and MDR).
          > >
          > > 9 Isobe M, Murakami G, Kataura A. Variations of the uncinate process
          > > of the lateral nasal wall with clinical implications. Clin Anatomy
          > > 1998;11:295-303.
          >
          > The morphology of the UP & nasal fontanelle is described in 119 human
          > specimens, which were examined both before & after removal of the
          mucosa.
          > Forms of the UP are classified & based on which site the process is
          > articulated, and each form is characterized in relation to the endonasal
          > endoscopic operative technique.
          > - Type I: The infero-posterior tip of the UP is articulated to the
          inferior
          > concha (turbinate). This was the most frequently observed type.
          > - Subtype I-b: The UP adhered to the inferior concha along the
          > antero-inferior margin. The anterior nasal fontanelle was closed by
          the UP
          > adhesion; therefore, special attention is required not to damage the
          > lacrimal bone.
          > - Type N: The tip of the UP had no articulation and made a free edge. It
          > reduces the bony resistance at surgery.
          > - Type S: The tip articulated to the superior structures, such as
          the bulla
          > ethmoid, medial orbital wall, tegument of the maxillary sinus &
          basal area
          > of the ethmoid sinus. These structures are known as high-risk areas of
          > endonasal surgery (Levine 1993).
          > - Type P: The tip articulated with the perpendicular plate of the
          palatine
          > bone. The UP was prolonged posteriorly. Attention should be paid to the
          > sphenopalatine artery, which goes through the posterior edge of the
          middle
          > concha.
          > 4 additional variations (combinations of the above basic types,
          Variations
          > IS, IP, SP & ISP) were also observed.
          > ______
          >
          > >
          > > --- In AAT@yahoogroups.com, "DDeden" <alas_my_loves@> wrote:
          > >>
          > >> Very interesting article by Croatian Medical Journal, connects
          stimuli
          > >> of inferior conchae to bronchial closure and HR decrease (MDR).
          > >>
          > >> See ** 1/2 way down for specific connections, if in hurry.
          > >>
          > >> December 1998 (Volume 39, Number 4)
          > >> Influence of Nasal Fontanel Receptors on the Regulation of
          > >> Tracheobronchal Vagal Tone
          > >> Damir Mili�i�, Ranko Mladina1, Davorin �ani�, Drago Prgomet, Dinko
          > > Leovi�
          > >> Department of Otorhinolaryngology and Cervicofacial Surgery, Dr.
          Josip
          > >> Ben�evi� General Hospital, Slavonski Brod; and 1Department of
          > >> Otorhinolaryngology, University Hospital Center Zagreb, Zagreb,
          Croatia
          > >>
          > >> Aim. To test the hypothesis according that the receptors located in
          > >> the nasal fontanels influence the regulation of the tracheobronchial
          > >> tree vagus tone.
          > >> Methods. Changes in respiratory parameters (forced expiratory volume
          > >> in the first second- FEV1 and total resistance- Rt) occurring
          > >> consequentially to light mechanical nasal stimulation were determined
          > >> in healthy volunteer, non-smokers using spirometric and body
          > >> plethysmographic measurements. The parameters were measured
          before and
          > >> at 15 and 60 min after mechanical stimulation with cotton pledge.
          > >> Results. In subjects in whom the middle nasal meatus was
          stimulated by
          > >> a cotton pledge soaked in saline, FEV1 decreased (p=0.01) and Rt
          > >> increased (p=0.03). In subjects in whom the middle nasal meatus was
          > >> stimulated by a cotton pledge soaked in 5% cocaine solution, no
          change
          > >> was observed. In the control group of subjects, in whom the inferior
          > >> nasal concha was stimulated by a cotton pledge soaked in saline, only
          > >> a statistically significant decrease for FEV1 (p=0.04) was found.
          > >> Conclusion. There is a reflex communication between the nasal
          fontanel
          > >> receptors and lungs, which is regulating the tracheobronchial vagal
          > >> tone and resistance in lung airways. Further studies of this
          important
          > >> physiologic relation are needed.
          > >>
          > >> Key words: bronchoconstriction; lung volume measurements; nasal
          > >> cavity; nasal mucosa; lung comliance; pulmonary ventilation;
          > >> respiratory function tests; trachea; vagus nerve
          > >>
          > >> The key role of the nose is to adjust the air flow and nasal
          > >> resistance (1). Nasal resistance is the crucial element in achieving
          > >> optimal alveolar ventilation for the respiratory work performed.
          > >> Studies on the air flow have shown a nearly constant volume flow in
          > >> particular segments and almost exclusive presence of laminar movement
          > >> (regardless of the air flow rate) along the surface of nasal mucosa.
          > >> The flow mostly proceeds through the middle and inferior part of the
          > >> nose, i.e. the region of middle nasal meatus and inferiorly between
          > >> inferior nasal concha and septum (2). The nasal cavity lacks
          > >> flexibility, except in the segment bordering with the maxillary
          > >> sinuses in the part of middle nasal meatus. There are two spaces
          > >> covered by mucosa, termed by Zuckerkandel as inferior and posterior
          > >> nasal fontanel (3). The nonmyelinated cholinergic endings (C-fibers)
          > >> conduct the stimulus caused by mechanical, chemical and thermal
          > >> irritants and are the only receptors that have been histologically
          > >> verified in nasal mucosa. Since they are stimulated by negative
          > >> pressure, they also function as flow receptors (4,5). Fibers from the
          > >> nasal mucosa constitute the parts of the first (ophthalmic) and
          second
          > >> (maxillary) branches of the trigeminal nerve. They are
          somatotopically
          > >> organized and grouped in the Gasserian ganglion and the principal
          > >> sensory nucleus and spinal trigeminal nucleus (6). A relationship
          > >> between the trigeminal nerve stimulation and vagal ambiguus nucleus
          > >> suggests that trigeminal stimulation modifies the neuronal firing
          > >> pattern and consequently causes changes in the vagal outflow (7).
          > >> Results of a number of animal experiments have demonstrated that
          > >> changes in the pulmonary resistance occurring during nasal mucosa
          > >> stimulation, are eliminated by resection of the ethmoidal nerve or
          > >> vagal nerve (8). This clearly points to the existence of nerve
          reflex,
          > >> but its characteristics, afferent part origin, nature of physiologic
          > >> stimulation, time of reflex exhaustion, compensatory mechanisms, and
          > >> pattern of efferent function have not yet been clarified.
          According to
          > >> our hypothesis, the region of the afferent part of the reflex in the
          > >> nose is the one which meets the following conditions: (a) flow of air
          > >> at a certain rate through a segment of the nose, whereby the amount
          > >> and rate are constant for certain states of the body (rest,
          exercise),
          > >> whereas the rate of air flow through this segment should
          substantially
          > >> differ from the flow rate through other segments of the nose; and (b)
          > >> the structures stimulated on inspiration (negative pressure,
          > >> Bernoulli's effect) and expiration (positive pressure) should be
          > >> elastic and free in space to allow the highest possible amplitude,
          > >> i.e., a free range of possible amplitudes.
          > >> The only part of the nose which meets both these criteria is the
          > >> region in the middle nasal meatus known as the inferior and posterior
          > >> nasal fontanels. They are made of a network of fibers continuing to
          > >> the periosteum. Above this network there is a tissue rich in
          cavernous
          > >> spaces abundant in nonmyelinated nervous endings on both sides. These
          > >> structures are bilaterally superimposed by a layer of respiratory
          > >> epithelium. The average infero-superior length of the anterior
          > >> fontanel is approximately 11 mm and the anterior-posterior one
          > >> approximatly 18 mm. Regarding the posterior fontanel,
          inferio-superior
          > >> length is approximately 11 mm and antero-posterior one approximately
          > >> 17 mm (9).
          > >> The "father" of modern nasal endoscopy, Professor Messerklinger,
          > >> noticed movements in the nasal fontanels: I have seen slight inward
          > >> and outward movements of healthy fontanels with forced nasal
          breathing
          > >> (3).
          > >> In this study, we tried to cause maximal receptor stimulation by
          light
          > >> mechanical tactile stimulation of ethmoidal nerves which are
          connected
          > >> with second-order low threshold mechanoreceptive neurons (10) and to
          > >> compare stimulation and anesthesia of the two regions of the nose.
          > >> Induced stimulation was assumed to result in the maximal response of
          > >> the vagus tone, i.e., smooth muscle of the tracheobronchial tree,
          with
          > >> resulting changes in spirometric and body plethysmographic
          parameters.
          > >> We wanted to confirm the trigeminus-mediated effect on the vagus
          > >> parasympathetic tone of tracheal and bronchial smooth muscle, and to
          > >> try and proof the nerve endings � receptors in the nasal cavity
          mucosa
          > >> of the nasal fontanels.
          > >> Subjects and Methods
          > >> Thirty healthy volunteers, non-smokers, 15 women and 15 men, aged
          > >> 14-61 years, with no chronic diseases in their rhinologic and
          > >> pulmologic history and no data on acute rhinologic or pulmologic
          > >> disease during the month preceding the study, were randomly divided
          > >> into three groups. Group 1 included ten subjects, five women and five
          > >> men, aged 18-56 years, mean age 31.8 years. Group 2 consisted of ten
          > >> subjects, five women and five men, aged 18-58 years, mean age 31.3
          > >> years. Control group included ten subjects, five women and five men
          > >> aged 18-61 years, mean age 32.1 years. There was no significant
          > >> difference in age, body height and weight between the three groups
          > >> In the group 1, a cotton pledge soaked in saline was inserted in the
          > >> middle nasal meatus on both sides. In the group 2, a cotton pledge
          > >> soaked in 0.5 ml of 5% cocaine solution was inserted in the middle
          > >> nasal meatus on both sides. In the control group a saline-soaked
          > >> cotton pledge was bilaterally inserted between inferior nasal concha
          > >> and septum, up to the upper level of the concha. The air flow through
          > >> this part is equal to that through the middle nasal meatus (11), but
          > >> is characterized by the presence of the reflex origin influencing
          > >> cardiac action via the vagus nerve (12).
          > >> The cotton pledge inserted was large enough to adhere to the mucosa,
          > >> producing light mechanical stimulation without dropping out
          > >> spontaneously, and without producing discomfort. The pledge was well
          > >> squeezed out before insertion, to avoid undesirable stimulation or
          > >> anesthesia of other parts of the nasal mucosa. The first measurement
          > >> after 15 minute-delay offered the elimination of any pain-caused
          > >> changes due to insertion of the pledge.
          > >> The parameters of lung ventilation were assessed by body
          > >> plethysmography on a Bodyscreen II (Dr�ger GmbH, L�beck,
          Germany). All
          > >> parameters were measured three times: one minute before, and 15
          and 60
          > >> minutes after the insertion of cotton pledges. Mean values were used
          > >> for statistical evaluation. The parameters measured were: forced
          > >> expiratory flow in the first second (FEV1), peek expiratory flow
          (PEF)
          > >> and total resistance (Rt). These parameters are commonly used in the
          > >> evaluation of the obstructive character of the tracheobronchial tree
          > >> pathology.
          > >> The study was approved by the hospital ethics committee, and an
          > >> informed consent was obtained from all subjects.
          > >> Data analysis was done using SPSS PC 3.0 software ( SPSS inc.,
          > >> Chicago, Ill, USA). Normal distribution was tested by
          > >> Kolmogorov-Smirnov nonparametric test. As all results showed normal
          > >> distribution, they were tested by two-tailed paired Student's t test.
          > >> Results
          > >> Mean values of measured parameters before, and 15 and 60 minutes
          after
          > >> the insertion of cotton pledges are shown in Table 1.
          > >> Table 1: Respiratory parameters (mean�SD) in the normal subjects in
          > >> whom a cotton pledge soaked in saline was inserted in the middle
          nasal
          > >> meatus on both sides (group 1); those in whom a cotton pledge soaked
          > >> in 0.5 mL of 5% cocaine solution was inserted in the middle nasal
          > >> meatus on both sides (group 2); and control group with a
          saline-soaked
          > >> cotton pledge bilaterally inserted between inferior nasal concha and
          > >> septum, up to the upper level of the concha [view this table]
          > >>
          > >> Group 1
          > >> A statistically significant decrease between the breathing parameters
          > >> measured before and 15 min after the saline-soaked pledge insertion
          > >> was observed for FEV1 (p=0.01) and statistically significant increase
          > >> for Rt (p=0.03). After 60 min, a statistically significant decrease
          > >> from the initial value was found for PEF (p=0.01) and an increase for
          > >> Rt (p=0.048).
          > >> Group 2
          > >> There was no statistically significant difference between the values
          > >> of the breathing parameter measured before and 15 or 60 min after the
          > >> insertion of cotton pledge soaked in 5% cocaine.
          > >> Control group
          > >> With the insertion of a saline-soaked cotton pledge between inferior
          > >> nasal concha and septum, a statistically significant decrease was
          > >> observed between the FEV1 values measured before and 15 min after the
          > >> pledge insertion (p=0.04), but not 60 min after the insertion of the
          > >> pledge.
          > >>
          > >> ** Discussion
          > >> The starting hypothesis of the study was the existence of a
          reflex arc
          > >> between the nasal mucosa and smooth muscles of the tracheobronchial
          > >> tree. There is a reflex, named nasopulmonary reflex, which causes
          > >> bronchoconstriction in humans after the stimulation of the nasal
          > >> mucosa by cold air (13,14). This bronchoconstriction in animals
          can be
          > >> prevented by the resection of the ethmoidal or vagal nerve (8).
          > >> It is well known that the area innervated by the trigeminal nerve
          is a
          > >> potent reflexogenic area (diving reflex, corneal reflex, sneezing).
          > >> The physiology of these reflexes is based on the more or less painful
          > >> stimuli (mechanical or chemical irritants and low temperature). The
          > >> most potent of them regarding the influence upon the vagal tone
          is the
          > >> diving reflex. It is a protective reflex against drowning and is
          > >> induced by immersion of the face in ice water or by cooling of the
          > >> face or forehead (15). Bilateral application of cold stimulus to the
          > >> individual divisions of the trigeminal nerve showed that the
          > >> ophthalmic division was the most sensitive pathway for this reflex
          > >> (16). The nasal cavity is mostly innervated by maxillary division of
          > >> trigeminal nerve and therefore diving reflex is not engaged in normal
          > >> reflex physiology connected with the nose. It is also known that the
          > >> stimulation to the trigeminal branches may cause cardiac arrhythmia,
          > >> arrest, and changes in the blood pressure (12,17). These reflexes may
          > >> potentially be more harmful than beneficial to the man, therefore the
          > >> body must have some regulatory mechanisms to control the reflex
          > >> duration. This, however, makes research aimed at their exact
          > >> description quite difficult.
          > >> The model of light mechanical (permanent tactile) stimulation of the
          > >> region was chosen in order to achieve the strongest possible reflex
          > >> response from the presumed ethmoidal nerve fibers connected with low
          > >> threshold mechanoreceptive second-order neurons in the trigeminal
          > >> nuclei. These neurons receive only light tactile input and are not
          > >> responding to noxious chemical or mechanical stimuli applied to the
          > >> nasal cavity. These neurons were found in animal studies (10), and it
          > >> can be presumed that they also exist in humans.
          > >> Light mechanical stimulation used in our study closely resembles the
          > >> physiologic stimulation from air stream and could be considered a
          > >> modified physiologic stimulation best stimulating nerves within the
          > >> nasal cavity occurring during air flow in physiologic conditions. In
          > >> the control group, the same postulates were employed, and the target
          > >> for the stimulation was the mucosal region between inferior nasal
          > >> concha and septum which, unlike the middle nasal meatus, has the
          > >> characteristics of the nasocardial reflex arc structure and
          origin (12).
          > >> Tracheal and bronchial smooth muscles are innervated by
          > >> parasympathetic innervation via the vagus nerve, which can change
          > >> their tone and airway diameter (18). The changes occurring in the
          > >> tracheaobronchial tree and lungs due to the increased
          parasympathetic,
          > >> i.e., vagus tone, must therefore entail changes in the
          spirometric and
          > >> plethysmographic parameters measuring the airway flow and resistance
          > >> (FEV1, Rt).
          > >> Saline-soaked cotton pledge inserted in the region of the middle
          nasal
          > >> meatus, elicited significant changes of respiration parameters 15
          > >> minutes after stimulation, pointing to alterations in the width
          of the
          > >> major and medium intrapulmonary airways, i.e., increased Rt with
          > >> decreased FEV1. At 1 hour, a statistically significant difference was
          > >> found in the values of the parameters of PEF and Rt, which are
          > >> characteristic of alterations in major and medium intrapulmonary
          > >> airways (19) but may also suggest a gradual reflex exhaustion.
          > >> In the subjects in whom the region of the middle nasal meatus was
          > >> obstructed by a cotton pledge soaked in 5% cocaine solution, no
          > >> statistically significant changes in the respiratory parameters were
          > >> recorded either at 15 or at 60 minutes. This was the caused by the
          > >> exclusion of regular nerve firing from the region of the middle nasal
          > >> meatus, and anterior and posterior nasal fontanel caused by nerve
          > >> ending anesthesia by 5% cocaine solution.
          > >> With the cocaine anesthesia of the region, the afferent part of the
          > >> arc maintained the parasympathetic (vagus) nerve tone at the basal
          > >> values, despite the middle nasal meatus mechanical stimulation.
          > >> Recanalization of the complete air flow through the region of the
          > >> middle nasal meatus, caused by the obstruction of the part of the
          nose
          > >> between inferior nasal concha and septum, in the second group,
          > >> produced a mild increase of trigeminal nerve stimulation. That
          changed
          > >> the parasympathetic (vagal) tone as well as the airway diameter
          trough
          > >> its action on the smooth muscles of the lungs and
          tracheobronchial tree.
          > >> This indicates that a continuous physiologic stimulus maintains the
          > >> vagal function at a certain, constant level already known as resting
          > >> vagal tone (20,21). Changes in the stimulus intensity entail changes
          > >> in the function of tracheobronchial smooth muscle tone and airway
          > >> diameter trough the increased vagal tone.
          > >> References
          > >> 1 Knops JL, McCaffrey TV, Kern EB. Physiology. Clinical application.
          > >> Clinics of North America 1993;26: 517-34.
          > >> 2 Hahn I, Scherer PW, Mozell MM. Velocity profiles measured for
          > >> airflow through a large-scale model of the human nasal cavity. J Appl
          > >> Physiol 1993;75: 2237-87.
          > >> 3 Messerklinger W. Endoscopy of the nose., Baltimore-Munich: Urban &
          > >> Schwarzenberg; 1978.
          > >> 4 Tsubone H. Nasal "pressure" receptors. Nippon Juigaku Zasshi
          > >> 1990;52:225-32.
          > >> 5 Tsubone H. Nasal flow receptors of the rat. Resp Physiol
          > > 1989;75:51-64.
          > >> 6 Walois F, Larnicol N, Rose D, Duron B. A comparative HRP study of
          > >> the neuronal supply to the inferior and superior nasal meatus in the
          > >> cat. Neurosci Lett 1992;139:234-8.
          > >> 7 Komatsubara J. Effects of trigeminal stimulation on the vagal
          > >> ambiguus neurons. Kanagawa-Shigaku 1989;23:598-609.
          > >> 8 Whicker JH, Kern EB, Hyatt R. Nasopulmonary reflex: Evaluation in
          > >> the nonparalyzed and paralysed anaesthetized dog. Annals of
          > >> Otolaryngology 1978; 87:91-8.
          > >> 9 Isobe M, Murakami G, Kataura A. Variations of the uncinate process
          > >> of the lateral nasal wall with clinical implications. Clin Anatomy
          > >> 1998;11:295-303.
          > >> 10 Lucier GE, Egizii R. Characterization of cat nasal afferents and
          > >> brain stem neurons receiving ethmoidal input. Exp Neurol
          1989;103:83-9.
          > >> 11 Baraniuk JN, Kaliner M. Neuropeptides and nasal secretion. AM J
          > >> Physiol 1991;261:223-35.
          > >> 12 Betlejewski S, Burduk D. Der nasokardiale reflex.
          > >> Otorhinolaryngologia Nova 1995;5:91-4.
          > >> 13 �ercer A. Investigations sur l' influence reflectoire de la cavite
          > >> nasale surt le poumon du meme cote. Acta Otolaryngol (Stockh)
          > > 1930;14:82.
          > >> 14 �ercer A. Nos i dihanje. Radovi JAZU 1935;251:1-38.
          > >> 15 Allen MT, Shelley KS, Boquet AJ Jr. A comparison of cardiovascular
          > >> and autonomic adjustments to three types of cold stimulation tasks.
          > >> Int J Psychophysiol 1992;13:59-69.
          > >> 16 Khurana RK, Watabiki S, Hebel JR, Toro R, Nelson E.. Cold face
          test
          > >> in the assessment of trigeminal- brainstem-vagal function in humans.
          > >> Ann Neurol 1980;7:144-9.
          > >> 17 Allison DJ. Dangerous reflexes from the nose. Lancet (letter)
          > >> 1977;1:909.
          > >> 18 Barnes PJ. Neural control of human airways in health and disease.
          > >> Am Rev Respir Dis 1986;134:1289-314.
          > >> 19 �u�kin E. Testovi plucnih funkcija. In: Gamulin S, Maru�i� M,
          > >> Krvavica S, editors. 3rd ed. Zagreb: Medicinska naklada; 1995. p.
          656-9.
          > >> 20 Olsen CR, Colesbarth HJH, Mebel P, Nadel JA, Staub NC. Motor
          > >> control of pulmonary airways studied by nerve stimulation. J Appl
          > >> Physiol 1965;20:202-8.
          > >> 21 de Troyer A, Yernault J-C, Rodenstein D. Effect of vagal blockade
          > >> on lung mechanics in normal man. J Appl Physiol 1979;46:217-26.
          > >>
          > >> Recieved: March 23, 1998
          > >> Accepted: June 16, 1998
          > >>
          > >> Correspondence to:
          > >> Damir Mili�i�
          > >> Department of Otorhinolaryngology and Cevicofacial Surgery
          > >> Dr. Josip Ben�evi� General Hospital
          > >> Andrije �tampara 42
          > >> 35000 Slavonski Brod, Croatia
          > >> opbolsb@
          > >>
          > >> crta.gif (62 bytes)
          > >> Copyright � 1997 by the Croatian Medical Journal. All rights
          reserved.
          > >> Created 20/1/99 - Last Modified 20/1/99
          > >> Created and maintained by: Tinman
          > >>
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