Role of the vagus nerves in anaphylaxis and histamine-induced bronchoconstrictions in guinea-pigs.

TLDR: It is suggested that “lung irritant receptors” in the bronchial epithelium are the afferent end‐organs involved in the respiratory responses of guinea‐pigs to anaphylactic reactions and to intravenous injections of histamine acid phosphate.

Abstract: 1. The effects of vagotomy on the respiratory responses of guinea-pigs to anaphylactic reactions and to intravenous injections of histamine acid phosphate are described.2. In spontaneously breathing guinea-pigs, vagotomy reduced by 50% or more the decreases in total lung conductance (bronchoconstriction) and the decreases in lung compliance, and almost abolished the rapid shallow breathing due to histamine.3. In paralysed, artificially ventilated guinea-pigs, vagotomy reduced by more than 33% the decreases in total lung conductance, but had little effect on the changes in lung compliance due to histamine.4. In paralysed, artificially ventilated guinea-pigs, vagotomy reduced by 75% the decrease in total lung conductance and halved the decrease in lung compliance due to anaphylaxis.5. We conclude that a vagal reflex is mainly responsible for the rapid shallow breathing due to histamine, and partly responsible for the bronchoconstrictions due to histamine and to anaphylaxis in guinea-pigs. We suggest that "lung irritant receptors" in the bronchial epithelium are the afferent end-organs involved.