Effects of AT1 receptor block begun late in life on normal cardiac aging in rats.

The goal of this study was to determine how short-term (12 weeks) angiotensin type I (AT1) block begun late in life affects aspects of myocardial biology and physiologic function altered by normal aging. Exercise capacity, myocardial morphology, histopathology, and coronary vascular function (degree of coronary vasodilation in response to adenosine) were evaluated in 53 Fischer 344 rats. Adult (6 months of age) and old (21 months of age) rats were studied after 12 weeks of either control drinking water, a low dose of candesartan that did not significantly lower blood pressure (1 mg/kg/d), or a high dose of candesartan (10 mg/kg/d).