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

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.