Experiences with Blockade of the Renin System in Human Hypertension Using Converting Enzyme Inhibitor SQ 20,881 and Saralasin

The development of agents which are capable of producing in vivo angiotensin II blockade has provided to investigators and clinicians alike the opportunity to determine and to quantify the extent to which the renin-angiotensin system participates in the maintenance of hypertensive states. High levels of plasma renin activity relative to the state of sodium balance have been documented in patients with malignant, surgically remediable renovascular hypertension and also in some patients with essential hypertension.1 The recent development of the angiotensin II analogue sar1-ala8-angiotensin II (saralasin) provided evidence to support the concept that these elevated renin levels are in fact pa…