Angiotensin skin tests.

MANY ATTEMPTS have been made to establish the relationship between angiotensin, human hypertension, and experimental hypertension. Three groups have reported the successful demonstration of a pressor material in varying amounts in the blood of patients with benign and malignant hypertension.-3 Boucher, Biron, and Genest2 claim that the material they isolated gave pressor reactions, chemical reactions, and chromatographic and electrophoretic findings similar to those of pure angiotensin. They have also reported the presence of a depressor fraction in blood. The isolation of a relatively small amount of angiotensin in normotensives and the presence of this depressor fraction suggest that the homeostatic regulation of blood pressure involves, in some measure, the antagonistic activity of these components. The depressor material demonstrated in the blood by Boucher et al. is too small, however, to enable comparison with the antipressor material isolated from the kidney by Jablons.4 5