The problem whether circulating angiotensin is, as catecholamines, excreted in urine was investigated in the hope that the study of renin-angiotensin system would be greatly facilitated, if it is the case in human or in experimental animals.
Though the assay method used here could accurately estimate angiotensin in urine in low concentrations down to 0.05 μg./100 ml., no angiotensin was found in the urine of healthy or hypertensive subjects including a patient with unilateral renal arterial stenosis with severe hypertension.
Infusion of angiotensin in doses enough to cause violent elevation of blood pressure resulted in no definite excretion of it in urine.
It is concluded that the circulating angiotensin is not excreted in urine in any significant amount.
