Papers of the Week

Cough in chronic respiratory diseases is a common symptom associated with significant comorbidities including visceral pain. Available antitussive therapy still has limited efficacy. Recent advances in the understanding of voltage-gated sodium channels (Nas) lead to the rational hypothesis that subtype Na1.7 is involved in initiating cough and thus may present a promising therapeutic target for antitussive therapy. We evaluated the antitussive effect of Na1.7 blocker PF-05089771 administered systemically and topically in awake guinea pigs using capsaicin cough challenge. Compared to vehicle, peroral or inhaled PF-05089771 administration caused about 50-60% inhibition of cough at the doses that did not alter respiratory rate. We conclude that the Na1.7 blocker PF-05089771 inhibits cough in a manner consistent with its electrophysiological effect on airway C-fibre nerve terminals.