Studies of reversed anaphylaxis in the perfused guinea-pig lung.

Histamine release was produced in the isolated perfused guinea-pig lung by injecting the pulmonary artery with rabbit antiserum to guinea-pig γ-globulin. The activity of the antiserum was absorbed by electrophoretically fast migrating guinea-pig γ-globulin but not by slow γ-globulin. Histamine release was enhanced by maleate or succinate and was inhibited by 20°, 45°, phenol, iodoacetate, N-ethylmaleimide, adrenaline, theophylline or deprivation of calcium. There was no apparent dependence on complement. These characteristics were the same as those of histamine release activated by antigen in guinea-pig lung sensitized with antibody. Therefore, the term reversed anaphylaxis was considered applicable to this reaction.