The Guinea Pig Sensitized by House Dust Mite: A Model of Experimental Cough Studies.

Abstract

The guinea pig sensitized by ovalbumin is the most widely used model to study cough experimentally, as the neurophysiology of the vagus nerve in the guinea pig is closest to humans. Nonetheless, the choice of the antigen remains questionable, which influences the translation of results into clinical medicine. The present study seeks to develop an alternative model of cough study using house dust mite sensitization (HDM). Thirty guinea pigs were divided into the HDM group, ovalbumin (OVA) group, and control group based on their cough response to 0.4M citric acid. In the HDM group animals were sensitized by 0.25%HDM aerosol, which they inhaled for 5min over 5days, followed by inhalation of 0.5%HDM in the same protocol. Sensitization was confirmed by a skin test. Symptoms of allergic rhinitis were induced by intranasal application of 15μl 0.5%HDM and cough challenges with citric acid were performed. Airway resistance was measured in vivo by Pennock's method. We found that both HDM and OVA-sensitized groups showed a significantly enhanced nasal reactivity and cough response compared with controls. The airway resistance data did not show significant differences. We conclude that the HDM cough model replicates functional aspects of the OVA model, which may make it an alternative to the latter. However, the superiority of the HDM model for experimental cough studies remains to be further explored.