Modulation of experimentally-induced cough by stimulation of nasal mucosa in cats and guinea pigs

• Published in: Respiratory physiology & neurobiology Vol. 142; no. 2; pp. 225 - 235
• Main Authors: Plevkova, J., Kollarik, M., Brozmanova, M., Revallo, M., Varechova, S., Tatar, M.
• Format: Journal Article
• Language: English
• Published: Amsterdarm Elsevier B.V 15-09-2004; Elsevier
• Subjects: Animals; Biological and medical sciences; Blood Pressure - drug effects; Blood Pressure - physiology; Capsaicin; Capsaicin - pharmacology; Cat; Cats; Cough; Cough - chemically induced; Cough - physiopathology; Disease; Guinea pig; Guinea Pigs; Histamine - pharmacology; Mammals; Medical sciences; Nasal afferents; Nasal Mucosa - drug effects; Nasal Mucosa - physiology; Neurons, Afferent - drug effects; Neurons, Afferent - physiology; Non tumoral diseases; Otorhinolaryngology. Stomatology; Pharmacological agents; Physical Stimulation - methods; Pneumology; Post-nasal drip; Respiration - drug effects; Respiratory system : syndromes and miscellaneous diseases; Rhinitis; Species Specificity; Stimulation, Chemical; Syndrome; Tidal Volume - drug effects; Tidal Volume - physiology; Time Factors; Upper airways; Upper respiratory tract, upper alimentary tract, paranasal sinuses, salivary glands: diseases, semeiology; Wakefulness - drug effects; Wakefulness - physiology; Post-nasal drip; Guinea pig; Disease; Rhinitis; Pharmacological agents; Capsaicin; Cat; Upper airways; Nasal afferents; Mammals; Cough; Syndrome; Nose disease; Upper respiratory tract; Pathogenesis; Mucosa; ENT disease; Fissipedia; Carnivora; Respiratory disease; Rodentia; Intranasal administration; Vertebrata; Experimental disease; Mammalia; Animal
• ISSN: 1569-9048; 1878-1519
• DOI: 10.1016/j.resp.2004.06.006

Stimulation of afferent nerves in upper airways may contribute to the pathogenesis of chronic cough in chronic disorders of nose and/or sinuses. We tested the hypothesis that stimulation of the nasal afferent nerves enhances experimentally-induced cough. Intranasal administration of capsaicin (50
μM, 25
μl) did not evoke cough in anaesthetized cats, but enhanced cough induced by mechanical stimulation of the tracheobronchial mucosa (number of coughs, median [IQR]) (6.5 [5.5–8.5] versus 10 [7–14];
P = 0.028,
n = 13). In contrast, intranasal histamine (16
mM, 25
μl) had no effect. Intranasal capsaicin (50
μM, 15
μl) did not evoke cough, but enhanced cough evoked by mechanical stimulation of the tracheobronchial mucosa (1 [1–3] versus 3 [2–4];
P = 0.0037,
n = 15) in anaesthetized guinea pigs and cough induced by inhalation of citric acid (0.3
M, 2
min) in awake guinea pigs (3 [2–5] versus 5 [3–7],
P  0.0026,
n = 23). We conclude that stimulation of nasal afferent nerves with capsaicin enhances experimentally-induced cough. Our results suggest that afferent inputs from the nose interact with the cough reflex pathways in a manner that enhances cough.