ANGGARD, E., U. BERGQVIST, B. HOGBERG, K. JOHANSSON, I. L. THON and B. UVNAS. Biologically active principles occurring on histamine release from cat paw, guinea pig lung and isolated rat mast cells. Acta physiol. scand. 1963. 59. 97-1 10. -Histamine release was induced from perfused cat paws and isolated rat mast cells with compound 48/80, and from sensitized guinea pig lungs with antigen. Concomitantly occurring biologically active substances were separated by various chromatographic procedures (silicic acid column, silicic acid impregnated paper, etc.). From all the species several spasmogenic principles were obtained. Chemical and biological properties indicated the presence of unsaturated fatty acids, phosphatidyl and phosphatidal choline and an "SRS" principle. The "SRS" principles from the three species seemed to be identical or very closely related. Phosphatidase A-like and chymotrypsin-like enzymes are present in mast cells. Such enzymes are the only enzymes shown to be able to degranulate mast cells. The possible connection between these enzymes and the formation of spasmogenic principles during histamine release is discussed. I n a series of papers we have presented evidence supporting the view that the histamine release that occurs i n the presence of compound 48/80, extracts from Cyanea a n d Ascaris (in the cat a n d rat), a n d antigens (in the guinea pig), is brought about by identical or very similar release processes in the mast cells of the three animal species UVNAS 1960, UVNAS 1961). T h e 7-633015. Acta physiol. scand. Vol. 59. 97
