The derivation of an inbred line of rats which develop asthma-like symptoms following challenge with aerosolized antigen.

Sensitized Sprague-Dawley rats developed respiratory impairment after challenge with aerosolized antigen. The response to challenge was heterogeneous. A proportion of each group of rats developed dyspnea and other symptoms similar to asthma; the remainder developed apnea but no other symptoms. Selective breeding from rats which developed dyspnea increased the incidence from 44% in F0 to 55% in F1 and greater than 90% in F2 and F3. Inbreeding also produced a significant increase in the duration of antigen-induced dyspnea. The results from the selective inbreeding suggest antigen-induced dyspnea is controlled genetically, possibly by multiple gene loci. These inbred rats constitute a population which have a predictable response to aerosolized antigen challenge. They should have utility in investigating allergic asthma and evaluating potential new drugs.