硒对大鼠心肌亚细胞结构过氧化体系作用的动态观察

EFFECT OF SELENIUM ON LIPID PEROXIDATION OF CARDIAC SUBCELLULAR STRUCTURE IN RATS

用低硒饲料和其饲料补硒分别饲养大鼠1、2和3个月，动态观察了大鼠心肌抗氧化酶活性和亚细胞结构脂质过氧化物（LPO）水平的变化。结果：与同期补硒组比较，低硒组大鼠心肌胞液谷胱甘肽过氧化物酶（GPx）活性显著降低；线粒体GPx活性饲养2个月后明显降低；两组大鼠心肌胞液超氧化物歧化酶（SOD）活性无显著差别；低硒组大鼠心肌亚细胞膜LPO水平在饲养1个月后显著升高。表明硒对心肌亚细胞膜结构有保护作用。

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.