Experimental Study On Influence Of Olmesartan On The Stability Of Atheromatous Plaques In Rats

ObjectiveTo investigate the effects of Olmesartan on the expression of matrix metalloproteinase-9 (MMP-9) and the number of vascular smooth muscle cells (VSMC) and macrophages in rats with atherosclerotic plaque (AP) and to explore the mechanisms of increasing the stability of AP.MethodsThe experimental atherosclerotic models were induced by hyperlipid feeding for three months. Sixteen male Wistar rats were randomly divided into two groups:the model group which was fed with standard diets containing 2% cholesterol and the Olmesartan group which was fed with standard diets containing 2% cholesterol and Olmesartan 3mg/(kg·d). The proteinum expression of MMP-9 and the positive area of VSMC and macrophage cells in the AP were determined by the immunohistochemistry technique. The structures of the AP of the two groups were observed with an electron microscope. Take each rats'serum to detect the expression of MMP-9 by enzyme linked immunosorbent assay(ELISA)ResultsThe thickness of the plaque is less in the treatment group than the placebo(P<0.05). Compared with the model group, the proteinum expression of MMP-9 and the number of macrophage cells in the Olmesartan group were significantly decreased, the difference was statistically significant (P＜0.05), the number of VSMC in the Olmesartan group were significantly increased, it was statistically significant (P<0.05). Enzyme-linked immunosorbent assay (ELISA) show:compared with the normal group, the MMP-9 expression of the model group was significantly higher than the normal group, statistically significant (P<0.05), the MMP-9 expression of the normal rats serum is very few.The MMP-9 expression of the serum in the Olmesartan group was significantly lower than the model group,the difference was statistically significant (P<0.05).ConclusionOlmesartan may stabilize vulnerable plaque by suppressing the expression of MMP-9, reducing the number of macrophage cells and increasing VSMC. Key words:Olmesartan; Atherosclerosis; Matrix metalloproteinases-9; Macrophage; Vascular Smooth Muscle Cells...