Inhibition of rat mast cell degranulation and histamine release by histamine-rat gammaglobulin conjugate.

Histamin-rat-gamma-globulin conjugate inhibited degranulation and histamine release of rat peritoneal mast cells to a greater extent than the rat globulin or histamine alone. Since mast cells contain histamine receptors, it may be assumed that the histamine bound to the gamma-globulin combines with the rat mast cell histamine receptor and inhibits the degranulation and histamine release by a feedback mechanism.