الفهرس 
Introduction & Aim of the workOnly 14 pages are availabe for public view
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Abstract
Background: Atherosclerosis is a progressive vascular disease characterized by endothelial dysfunction, upregulation of cell adhesion molecules, accumulation of lipids, macrophages, smooth muscle cells (SMCs), and fibrous tissue in the arterial intima. The process of atherogenesis is still not completely understood, but it is generally believed that inflammation plays an important role in all stages of atherosclerosis. Calcium antagonists have been widely used for the treatment of patients with angina pectoris and hypertension. There is controversy about its effects on atherosclerosis. Aim of the work: This experimental study was conducted to evaluate the possible effect of Nifedipine, Amlodipine, Diltiazem and Verapamil on progression and regression of atherosclerosis. Matreials and Methods: The study was carried out in rabbits in which atherosclerosis was induced experimentally by feeding rabbits on cholesterolenriched diet. Rabbits either fed atherogenic diet alone or in combination with calcium channel blockers (CCBs) from the start of the study for 20 weeks to show the possible protective effect of CCBs on atherosclerotic process or fed atherogenic diet for 12 weeks and after the development of atherosclerosis (as confirmed by pathological examination & lipogram assay), CCBs were given with atherogenic diet for another 8 weeks to show the effect of CCBs on the progression of atherosclerosis (n = 30). Results: The data obtained in the present study showed the following: Administration of Nifedipine, Amlodipine, Diltiazem and Verapamil both during and after induction of atherosclerosis produced significant beneficial effects on serum lipid profile, MDA and soluble adhesion molecules, Pretreatment of rabbits with Nifedipine, Amlodipine, Diltiazem and Verapamil both during and after induction of atherosclerosis increased nitrite and decreased MDA release from isolated rabbit aortic rings, Incubation of aortic ring isolated from atherosclerotic rabbits with Nifedipine, Amlodipine, Diltiazem and Verapamil for 20 minutes significantly increase Nitrite release but significantly decreased MDA release from isolated aortic rings, Pretreatment of rabbits by Nifedipine, Amlodipine, Diltiazem and Verapamil during induction of atherosclerosis markedly slowed the progression of atherosclerosis and Administration of Nifedipine, Amlodipine, Diltiazem and Verapamil to atherosclerotic rabbits produced regression of atherosclerotic lesions. Conclusion: In the light of result of the present study, it can be concluded that; Nifedipine, Amlodipine, Diltiazem and Verapamil have equal atheroprotective potential on plaque development in the aortic tissue of New Zealand White rabbits. The atheroprotective effect of Nifedipine, Amlodipine, Diltiazem and Verapamil was greater when these drugs were given before development of atherosclerosis.