New therapeutic prospects of renin-angiotensin system inhibition.

Renin plays a major role in the control of blood pressure and water and electrolyte metabolism and it is clear that blocking of this system is particularly effective in the treatment of essential hypertension and heart failure. A large number of converting enzyme inhibitors have been synthesized. Converting enzyme inhibitors are remarkably active in heart failure and they reduce microalbuminuria and possibly maintain glomerular function. Blocking of the renin-angiotensin system by converting enzyme inhibitors is not accompanied by hypotension or reflex stimulation of the sympathetic nervous system. Converting enzyme inhibitors represent a major therapeutic advance in the field of cardiovascular and renal disease but the long-term effects of decreased angiotensin II levels are unknown. There are other ways to inhibit the renin-angiotensin system. The recent discovery of orally-active non-peptide angiotensin II antagonists opens a range of fascinating prospects. Another approach consists in inhibiting the reaction of renin on angiotensinogen, which is remarkably selective. Although it is too early to know whether these new approaches will be less active, more active or as active as current converting enzyme inhibitors, they may constitute a progress in relation to currently available treatments.