Changes in airway resistance induced by nasal inhalation of cold dry, dry or moist air in normal individuals. Fontanari, Pierre, Henri Burnet, Marie Caroline Zattara-Hartmann, and Yves Jammes. Laboratoire de Physiopathologie Respiratoire, Institut Jean Roche, Facult[acute]e de M[acute]edecine, Universit[acute]e de la M[acute]editerrann[acute]ee, Marseille. France
APStracts 3:0268A, 1996.
Naso-pulmonary bronchomotor reflexes elicited by mechanical or irritant stimulation of the nose are described in animals and asthmatic patients. However, few studies were devoted to the consequences of nasal breathing of cold and dry, or only dry or moist air on the bronchomotor control in normal individuals. The present study reported changes in interrupting resistance (Rint) measured during eupneic breathing of moderately cold (- 4 or -10 degrees C) and dry (0.3 % relative humidity, RH) air or of room air at 23 degrees C either dry (0.3 % RH) or moist (97 % RH). Nasal inhalation of cold (- 4 degrees C) dry air or only dry air increased significantly baseline Rint value (+ 17 % and + 21 %, respectively) throughout the 15-min test periods. The response to cold was significantly accentuated when the air temperature was lowered at -10 degrees C (+ 42%). After nasal anesthesia or inhalation of a cholinergic antagonist, cold air did not induce a change in Rint. Nasal inhalation of moist room air had no effect. No Rint changes were measured during oral breathing of the three test agents. It is concluded that the activation of cold- or osmoreceptors in the nasal mucosa induces protective bronchoconstrictor responses in normal individuals.

Received 29 September 1995; accepted in final form 7 May 1996.
APS Manuscript Number A1057-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 17 June 96