Abstract: | Two groups of weanling rats were fed on a low-selenium basal diet and the same diet supplemented with sodium selenite respectively, for 1, 2 and 3 months. The activities of glutathione peroxidase(GPx) in cardiac cytosol and mitochondri a, activity of superoxide dismutase(SOD) in cardiac cytosol and the contents of lipid peroxide in mito chondria, postmitochondrial supernatant, micro some and cytosol were determined. The results showed that at each feeding, cytosolic GPx activity from -Se rats was decreased significantly compared to those from +Se rats. Mitochondrial GPx activity from -Se rats was decreased significantly compared to those from +Se rats only in 2 months after being fed. During all the feeding periods, no significant difference in cytosolic SOD activity was found between the -Se and +Se groups, while the contents of lipid peroxide in mitochondria, postmitochondrial supernatant and microsome from -Se rats were significantly higher than those from +Se arts at each feeding time. These results indicate further evidence that the protective effects of selenium on myocardial subcel1ular system may be due to the enhancing of mvocardiac antioxidation. |