有氧运动抑制高脂血症小鼠主动脉壁超微结构改变

目的　探讨有氧运动在动脉粥样硬化 (AS)形成过程中对血管壁的保护作用。方法　结合血脂水平的测定 ,对实验性高脂血症小鼠主动脉壁超微结构改变及有氧运动对其影响进行观察。结果　有氧运动(HE)组的甘油三酯 (TG) ,总胆固醇 (TC) ,低密度脂蛋白 (LDL)均低于高脂膳食致动脉粥样硬化 (AS)组 (P<0 .0 1) ;高密度脂蛋白 (HDL)高于AS组 (P <0 .0 1)。透射电镜显示AS组小鼠内皮细胞严重受损 ,甚至出现核固缩 ,受损的内皮细胞间有含脂滴的白细胞向内皮下穿入 ,平滑肌细胞内粗面内质网及高尔基体增多 ,弹力纤维变形。而HE组仅出现弹力纤维的轻度变形及脂质沉积。结论　有氧运动除可降低血脂外 ,同时对血管壁具有保护作用 ,但尚不能完全阻止动脉粥样硬化形成

Aerobic Exercise Inhibits the Ultramicrostructural Alteration of Aorta,Wall in Hyperlipidemia Mice

Objective To explore the effect of siutable aerobic exercise on the formation and development of the atherosclerosis(AS) especially on the endothelium and the smooth muscular cell of the aorta wall. Method Fifteen female and fifteen male C57BL/6J mice at 8 weeks of age were divided into 3 groups at random: normal control group (NC=10), atherogenic diet group (AS=10), atherogenic diet and aerobic exercise group (HE=10). Microstructures of the ascending aorta were observed through transmition electron microscope. Results In HE group, total cholesterol(TC), triglyceride(TG), low density lipoprotein (LDL) were decreased (P<0.01), but high density lipoprotein (HDL) was increased (P<0.01) compared with AS group. It was found that endothelial cells of the ascending aorta were damaged severely (probably necrotic) with pyknotic cleaved nuclei in group AS. The white cells containing lipid droplets between these damaged endothelial cells were found located under endothdium, and the rough endoplasmic reticulum and Golgi complex were increased in number in smooth muscle cell with deformed elastic fibers. But in HE group, only lightly deformed elastic fibers and lipid deposit were observed. Conclusion In the condition of hyperlipidemia, aerobic exercise might have the effect on the protection of aorta wall besides decreasing plasma lipid but not the prevention of the formation of AS completely.