Passive Air-Pouch Anaphylaxis in Rats

Abstract

Induction of an experimental passive anaphylaxis of the air-pouch type, passive air-pouch anaphylaxis, was carried out in an attempt to induce a reproducible anaphylaxis model suitable for quantitative studies. Rats were injected subcutaneously with 10 ml of air into the dorsal skin to make an air-pouch and with 2 ml of antiserum at an appropriate dilution for passive sensitization, and then 5 ml of air was removed. The challenge with 5 ml of antigen solution into the air-pouch 48 h later provoked mast cell degranulation and increased vascular permeability induced by released histamine. Treatment with monovalent hapten prior to the antigen challenge almost completely inhibited histamine release and plasma exudation to levels similar to those in the nonsensitized group. In this model, mast cell-dependent late-phase allergic reaction, such as leukocyte migration or the increase of plasma exudation following mast cell degranulation, was not observed.

Passive Air-Pouch Anaphylaxis in Rats

“…We reported in the companion paper [1] that the degranulation of mast cells was observed in subcu taneous tissues of the pouch wall in PAPA and that the histamine level in the pouch fluid and the plasma exudation abruptly increased immediately after anti gen challenge. Furthermore, PAPA was shown to be reproducible and useful for quantitative measure ments and biochemical analysis of anaphylaxis.…”

“…In the preceding companion paper [1], we de scribed the induction of passive air-pouch anaphyla xis (PAPA), an experimental model of passive ana phylaxis of air-pouch type, in rats. In PAPA the increased plasma exudation was closely correlated with the heightened level of histamine in the pouch fluid immediately after the injection of the antigen so lution into the preformed air-pouch sensitized pas sively.…”