反复力竭运动后大鼠骨骼肌线粒体超微结构改变及维生素E的保护作用

Ultrastructural changes of the skeletal muscle cells of rats subjected to exhausting exercises and the protective effect of vitamin E

目的探讨反复力竭运动后大鼠骨骼肌线粒体超微结构改变及维生素E的保护作用。方法雄性SD大鼠30只随机分为安静对照组、力竭对照组、维生素E组,每组10只,后两组大鼠进行4周的反复力竭跑台训练,取股四头肌作超薄切片,透射电镜观察骨骼肌及骨骼肌线粒体形态、结构。结果4周反复力竭运动后,力竭组大鼠骨骼肌肌丝排列紊乱,线粒体肿胀和空泡变性,维生素E组骨骼肌超微结构图接近正常。结论反复力竭运动导致骨骼肌细胞坏死丢失,线粒体形态异常,口服维生素E对反复力竭运动大鼠骨骼肌线粒体具有保护作用,减少反复力竭收缩骨骼肌的坏死丢失。

Objective To investigate the ultrastructural changes of the mitochondria in the skeletal muscle cells of rats subjectedto repeated exhausting exercises on treadmill and the protective effct of oral vitamin E. Methods Thirty male SD rats wererandomized into control group (n=10), exhausting exercise group (n=10) and exhausting exercise group with oral vitamin Etreatment (n=10), with the latter two groups taking repeated exhausting running exercises on the treadmill in a course of 4weeks. At the end of the course of exercises, the rats were sacrificed and the quadriceps femoris muscles isolated for obser-vation the ultrastructures of the skeletal muscle cells by transmission electron microscope (TEM). Results After 4-weekexhausting exercises, themyofilaments of theskeletal muscle were seen in disordered alignment, and the mitochondriaexhibited abnormal morphological changes of swelling and vacuolar degeneration. In vitamin E-treated rats also undertakingthe exercise, the ultrastructures of the skeletal muscle cells were almost normal as compared with the normal control group.Conclusion Vitamin E can protect the function of the skeletal muscle mitochondria of rats taking repeated exhausting exercises.