[Anti-atherosclerotic action of hypotensive drugs]

Abstract

Hypertension is an important risk factor for the development of atherosclerosis. Traditional antihypertensive therapy is not fully effective in prevention of cardiovascular abnormalities of hypertension. Two classes of hypotensive drugs, calcium antagonists and angiotensin-converting enzyme (ACE) inhibitors, reduce atherosclerosis in several experimental models in animals. Anti-atherosclerotic effects of calcium antagonists include attenuation of endothelial dysfunction, prevention of LDL modification, stimulation of LDL receptor activity, inhibition of superoxide radical generation and inhibition of vascular smooth muscle cells proliferation and migration. In large angiographic trials calcium antagonists reduced the development of new atherosclerotic plaques. ACE inhibitors also lead to the lower incidence of atherosclerosis in experimental animals. They inhibit migration and proliferation of vascular smooth muscle cells, reduce macrophage-derived foam cell accumulation, preserve protective endothelium function, reduce LDL modification and increase fibrinolytic activity. It depends on reduced angiotensin II synthesis, increased concentration of kinins, substance P and angiotensin-(1-7), inhibition of leukotriene B4 formation and improvement of insulin action. In some studies they also reduce plasma lipids concentration, including lipoprotein (a). ACE inhibitors were found to be ineffective in prevention of restenosis after PTCA in human but data derived from large, multicenter trials indicate that they are effective in the secondary prevention of myocardial infarction.