Cardioprotective Effect of Enalapril in Renovascular and Angiotensin II Hypertension

Abstract

The influence of chronic treatment with enalapril or losartan (10 or 30mg/kg/24h, respectively) on cardiac mass was evaluated in one-kidney, one clip (1K-1C) hypertensive rats submitted to sodium restriction 3 weeks after clipping and in rats infused for 10 days with angiotensin II (ANGII: 200ng/kg/min). In 1K-1C hypertension, cardiac mass and arterial pressure were reduced to a similar extent by enalapril and losartan. In ANGII hypertension, enalapril and losartan blunted the increase in cardiac mass whereas losartan but not enalapril prevented the development of hypertension. The cardioprotective effect of enalapril was attenuated by concomitant blockade of bradykinin receptors (Hoe 140: 300pg/kg/24h) in both models. The beneficial influence of enalapril on cardiac mass appears to be independent of its effect on blood pressure and ANGII generation and seems partly mediated by endogenous bradykinin in these high ANGII models of hypertension.

Key Words:

• Cardiac Mass
• ACE Inhibitor
• Angiotensin II Receptor Antagonist
• Bradykinin Receptor Blockade
• Renovascular Hypertension
• Angiotensin II Hypertension