Effect of ACTH on human renin-angiotensin system

Abstract

Several investigators reported that the administrations of exogenous ACTH into various animals stimulated their renin-angiotensin systems. So I studied the effect of exogenous ACTH on renin-angiotensin system in man; especially human plasma renin activity and angiotensin II levels. Plasma renin activity was measured by the "improved" method of Skinner. For the measurement of plasma angiotensin II level, the preparation of antiangiotensin II serum was made out by combining of the rabbit serum albumin and the synthetic angiotensin II amide with the carbodiimide reaction (the method of Goodfriend et al) and injecting its combining material into several rabbits. And the extraction of angiotensin II from human plasma was carried out through the column of Dowex 50 W-X 2 (NH₄) by the method of Haas et al. The plasma angiotensin II level was radioimmunoassayed with the procedures of the dextran-coated charcol method. The human plasma renin activity and angiotensin II levels were significantly rised at 30 minutes after the intramuscular injections of ACTH (ORGANON) 25 units into the normotensives and the hy-pertensives, and were concomitantly failed at 60 or 120 minutes compared with the control values. And the plasma renin activity and angiotensin II levels of the normotensives could not differ from that of the hypertensives. It was concluded that the administration of exogenous ACTH into man could abruptly raise his plasma renin activity and angiotensin II level.