Induction of an allergic air-pouch inflammation in rats.

An allergic air pouch inflammation was induced on the dorsum of rats using azobenzenearsonate-conjugated acetyl bovine serum albumin as an antigen. Rats were immunized by intradermal injection with 5 mg of the antigen in 0.5 ml Freund's complete adjuvant saline (1:1) emulsion. 9 days after the immunization 8 ml of air was injected subcutaneously on the dorsum, and 24 h later 4 ml of 2% sodium carboxymethyl cellulose solution containing 2 mg of the antigen was injected into the preformed air pouch to provoke the allergic inflammation. In addition to the histological observations of the inflammatory tissues of the pouch wall, time course studies on the volume of the inflammatory pouch fluid, on the number and species of inflammatory cells in the pouch fluid and on the wet weight of granulation tissues were carried out to characterize the nature of the inflammatory reaction, which was shown to be suitable as a model to perform quantitative measurements and biochemical analyses of the allergic inflammation.