关键词: 基质金属蛋白酶, 动脉硬化

Abstract: To investigate the effect of N-acetylcysteine(NAC) on matrix metalloproteinases(MMPs) levels in rabbit carotid atherosclerotic plaque and morphological changes. Methods The model of rabbit atherosclerosis was built by injuring internal carotid through arterial canal balloon in vitro.These rabbits were treated with NAC for 6 weeks. Then the injuried arteries stained with HE were observed under light microscope and the levels of MMP-2 and MMP-9 in veinous blood from rabbits were detected by SDS-Page-Zymograph method.Moreover,the number of foam(spume) cells contained MMPs and tissue inhibitor of MMP-2(TIMP-2) were detected by method of immunochemistry.In addition,the status of vascular hyperplasia was proved by the area of new vascular inner membrane,the transverse section of vascular cavity and the thickness of vascular wall.Results The arterial lumen injury neointimal area in NAC group（1.72 mm²±0.26 mm²）was significantly smaller than that in control group（2.66 mm²±0.19 mm²）(P<0.05).The endothelial thickness in NAC group（0.132 mm±0.031 mm）was decreased compared with control group （0.231 mm±0.022 mm）（P<0.05）,and vascular cavity transverse section in NAC group（0.54 mm²±0.15 mm²）was larger than that in control group（0.31 mm²±0.12 mm²）（P<0.05）. On the same lengthof vascular wall,the number of foam cells containing MMPs in NAC group (8.0±1.8) was less than that in control group (22.0±2.2)（P<0.05）.The number of foam cells containing TIMP-2 in NAC group (10.0±1.2)was more than that in control group(6.0±1.6)（P<0.05）. The levels of MMP-2,pro-MMP-2 and pro-MMP-9 in NAC group were remarkably lower than those in control group（P<0.05）. Conclusion NAC has functions of inhibiting the increase of foam cells,preventing vascular sclerosis,inhibiting the degradation of atherosclerosis plaque induced by MMPs,thereby steadying the plaque.

Key words: matrix metalloproteinases, atherosclerosis