Angiotensin II blockade in patients with essential hypertension

Patients with essential hypertension were sodium deprived by five days on a 10 mM sodium diet and were then infused with an incremental infusion of saralasin, a competitive inhibitor of angiotensin II. Patients with normal renin hypertension showed no change in lying or standing blood pressure during the infusion of saralasin. Angiotensin II is not, therefore, directly maintaining blood pressure in these patients when sodium deprived by diet, and is therefore unlikely to be playing any direct role in maintaining their blood pressure on their normal sodium intake. Patients with low renin hypertension showed a significant rise in blood pressure during saralasin infusion. Saralasin may be a further method of distinguishing low renin hypertensives from other hypertensives if they are infused when sodium deprived by diet.