Active Bronchial Anaphylaxis in the Rat

Abstract

Sprague–Dawley female rats were immunized with egg albumin (EA) in aluminum hydroxide gel (AHG) and with or without Bacillus pertussis vaccine (BPV). Fourteen days later, the animals were anesthetized and challenged with EA intravenously. The resultant increase in tracheal pressure was recorded as an index of anaphylactic bronchoconstriction. Ventilation with tracheal pressures of 6 cm H2O (588 N/m2) allowed maximal development of bronchoconstrictor responses to specific antigen challenge that were similar in both pithed and pentobarbital-anesthetized preparations. Forced reinflation of the lungs did not affect the magnitude of the response but did facilitate its recovery. Serum titers evaluated by 3-h and 72-h passive cutaneous anaphylactic reactions indicated that reaginic antibodies were primarily involved, although other immunoglobulins may have played a contributory role. Antigen dose-responses were similar for both the EA-AHG and EA-AHG-BPV immunized groups of animals despite lower reaginic serum titers for the former group. Thus, an immediate-type bronchial anaphylactic response mediated primarily by reaginic antibodies can be elicited in rats and quantitatively assessed. The potential immunologic similarity of these animals to human allergic asthma suggests their utility for further investigation.