Angiotensin AT2 receptors:: control of renal sodium excretion and blood pressure

The renin-angiotensin system is a coordinated hormonal cascade of crucial importance in cardiovascular and renal function. The primary effector peptide angiotensin II functions at two major receptors, the AT(1) and AT(2) receptors. AT(2) receptors mediate vasodilation and natriuresis. Regarding vasodilator actions, AT(2) receptors oppose the AT, receptor-mediated vasoconstrictor action of angiotensin II. Regarding the natriuretic actions of AT(2) receptors, des-aspartyl(1)-angiotensin II, rather than angiotensin II, is the preferred agonist. Regarding both the vasodilator and natriuretic properties of AT(2) receptors, the beneficial blood pressure reduction and natriuretic responses to AT, receptor blockade are mediated, at least in part, by AT(2) receptor activation. In addition, AT(2) receptor activation suppresses renin biosynthesis and release at renal juxtaglomerullar cells. Therefore, AT(2) receptors are potential therapeutic targets in hypertension.