Monoclonal antibodies and nonpeptide antagonists to angiotensin II. Potential implications.

The introduction of agents capable of blocking the function of the renin-angiotensin system has had a profound impact on our knowledge of the physiology of the renin-angiotensin system and its role in various pathophysiological conditions, including hypertension. Saralasin and other angiotensin antagonists, peptides similar in chemical structure to angiotensin II itself, have been used since the early 1970s. Because saralasin and other angiotensin antagonists were found to lower systemic arterial pressure in conditions characterized by high renin levels (e.g., renovascular hypertension and sodium restriction) and to cause changes in renal hemodynamics and function, there was a renewed interest in the potential role that angiotensin II plays in hypertension. Later the realization that the venom of Bothrops jararaca possessed a substance capable of inhibiting the angiotensin converting enzyme (ACE) led to the design of synthetic ACE inhibitors, of which captopril is the prototype.