Sub-antihypertensive doses of ramipril normalize sarcoplasmic reticulum calcium ATPase expression and function following cardiac hypertrophy in rats

We examined the hypothesis that the angiotensin converting enzyme inhibitor ramipril at sub-antihypertensive concentrations could improve sarcoplasmic reticulum (SR) CaATPase expression and function in compensated hypertrophied rat hearts. Five weeks after abdominal aortic constriction, rats received a daily dose (50 μg/kg/day) of ramipril or vehicle for 4 weeks. Cardiac angiotensin-converting enzyme (ACE) activity increased with cardiac hypertrophy (CH) but returned to normal following ramipril treatment. SR CaATPase protein levels and activity decreased with CH (P 60% (P 30%, respectively. In the hypertrophied group, SR CaATPase increased by 35% (P < 0.05 n = 6) after ramipril treatment. Calsequestrin mRNA levels were unaffected by ramipril administration. In conclusion, ramipril normalizes SR CaATPase protein expression and function in pressure-overloaded and compensated CH. The effects of ramipril are however multifaceted, affecting RNA and protein expression differentially.link_to_subscribed_fulltex