RENIN INHIBITOR IN PLASMA OF URÆMIC PATIENTS

Abstract Addition of small amounts of plasma of uraemic patients with chronic glomerulonephritis to a mixture of renin and renin-free plasma decreased the rate of angiotensin formation to 66-89% of the value when saline solution was added. However, in the terminal stage of malignant hypertension inhibitory effect of plasma on angiotensin formation could not be observed, although plasma-renin activity was within normal range. This finding suggests that plasma of patients with uraemia contains a substance which inhibits the reaction of renin upon its substrate. This accords with the notion that the incubation method for the assay of plasma-renin does not estimate the absolute level of circulating renin, but rather estimates its activity in plasma as a whole.