REHABILITATION OF RHINITIS-RELATED COUGH

Abstract

This article tackles the role of sensory output from the nose in modulating cough elicited from other regions of the respiratory system. Guinea pigs were used for the experiments. We addressed the issue by inducing cough from the tracheo-bronchial region on the background of capsaicin-stimulated and mesocain-blocked nasal mucosa. We found that knocking out the nasal sensorium with local anesthesia abolishes the capsaicin-induced enhancement of tracheo-bronchial cough. We then examined the possibility of cough modification by systemic pharmacotherapy with a bioflavonoid, rutinoscorbin, in a guinea pig model of allergic rhinitis/sinusitis. We found that improvement of the rhinorrhea symptoms markedly diminished the cough response to chemical stimulation of the tracheo-bronchial region. We conclude that the cough reflex is subject to central convergence of peripheral neural pathways originating at distant anatomical locations. Our findings give credence to the notion of a substantial role of nasal mucosa, although it does not itself initiate cough, in cough regulation. That should be taken into account when designing respiratory rehabilitation paradigms.