DOES BLOCKADE OF ANGIOTENSIN-II RECEPTORS OFFER CLINICAL BENEFITS OVER INHIBITION OF ANGIOTENSIN-CONVERTING ENZYME

Angiotensin AT(1) receptor antagonists represent a new class of drugs for the treatment of hypertension. They are specific for the renin-ang iotensin system, selective for the angiotensin AT, receptor, and act i ndependently of the angiotensin II synthetic pathway. Blockade of the renin-angiotensin system at the receptor level should therefore be mor e complete. The high circulating levels of angiotensin II following an giotensin ATI receptor blockade could be beneficial in stimulating oth er unblocked angiotensin receptors, especially the AT(2) receptor. It has been proposed that the angiotensin ATI receptor, which is re-expre ssed or up-regulated during pathological circumstances, counterbalance s the effect of the stimulation of the angiotensin ATI receptor. Throu gh this mechanism, angiotensin ATI antagonists may be superior to ACE inhibitors in cardiac and vascular remodelling as well as in kidney in sufficiency. Long-term trials are required to demonstrate the possible clinical superiority of this new class of antihypertensive agents.