The effects of ACE inhibitors and other antihypertensive drugs on cardiovascular risk factors and atherogenesis.

The effects of antihypertensive therapy on the atherosclerotic process and differences among various treatment approaches have been studied in several animal models. Studies in cholesterol-fed rabbits have indicated that beta blockers and calcium antagonists can inhibit the development of aortic atherosclerosis induced by marked hypercholesterolemia. However, no such antiatherosclerotic action has been apparent with these agents in the Watanabe heritable hyperlipidemic (WHHL) rabbit. A study was conducted to determine the effects of the angiotensin-converting enzyme (ACE) inhibitor captopril administered orally for 9 months on the development of atherosclerosis in normotensive WHHL. Compared with controls, the treated animals had a significant reduction in atherosclerosis of the descending thoracic aorta. These effects were associated with significantly lower blood pressure, though within the normal range, in captopril-treated versus control animals. In the captopril group, the atherosclerotic plaques were thinner and less cellular than plaques of similar gross severity in control WHHL. The findings indicate that the ACE inhibitor captopril can inhibit atherogenesis in the WHHL, which has been resistant to such therapy with other antihypertensive drugs.