%0 Journal Article
%T Modulation of cough response by sensory inputs from the nose - role of trigeminal TRPA1 versus TRPM8 channels
%A Tomas Buday
%A Mariana Brozmanova
%A Zuzana Biringerova
%A Silvia Gavliakova
%A Ivan Poliacek
%A Vladimir Calkovsky
%A Manjunath V Shetthalli
%A Jana Plevkova
%J Cough
%D 2012
%I BioMed Central
%R 10.1186/1745-9974-8-11
%X In this study we addressed the question of possible bidirectional modulation of cough response in human healthy volunteers by nasal challenges with TRPA1 and TRPM8 agonists respectively. After nasal challenges with isocyanate (AITC), cinnamaldehyde, (£¿) menthol and (+) menthol (all 10-3 M) nasal symptom score, cough threshold (C2), urge to cough (Cu) and cumulative cough response were measured).Nasal challenges with TRPA1 relevant agonists induced considerable nasal symptoms, significantly enhanced urge to cough (p<0.05) but no statistically significant modulation of the C2 and cumulative cough response. In contrast, both TRPM8 agonists administered to the nose significantly modulated all parameters including C2 (p<0.05), Cu (p<0.01) and cumulative cough response (p <0.01) documenting strong anti irritating potential of menthol isomers.In addition to trigeminal afferents expressing TRP channels, olfactory nerve endings, trigemino ¨C olfactoric relationships, the smell perception process and other supramedullar influences should be considered as potential modulators of the cough response in humans.The cough reflex is not a static phenomenon, but is a flexible entity modulated by many central and peripheral neuronal mechanisms, sometimes termed ¡®cough plasticity¡¯ [1]. Stimulation of trigeminal terminals in the nose by the TRPV1 agonist capsaicin, and histamine significantly enhances cough response induced in laboratory animals. Such stimulation also up regulates cough responsiveness in human healthy subjects and patients with allergic rhinitis [2-5]. These findings suggest cough is enhanced by increased afferent drive form the nose to the sensory trigeminal nuclei and then by cooperation with the brainstem neuronal circuits modulating cough. Nucleus tractus solitarius (nTS) is believed to be the site important for modulation of cough reflex at the central level [6]. Naturally, if noxious substance enter the airways through the nose, then defensive mechanisms in this re
%K Cough
%K Nose
%K Irritants
%K Menthol
%K Trigeminal
%K Olfactory
%U http://www.coughjournal.com/content/8/1/11