ABSTRACT
Weanling rats were fed with a low-selenium diet (Se 0.009mg/kg, — Se group) and the diet supplemented with sodium selenite (Se 0. 232mg/kg,+ Se group) for 1, 2 and 3 months respectively. The generation rate of superoxide radical(O_2~-), activity of manganese dependent superoxide dismutase (Mn-SOD) in heart mitochondria and blood Se concentration from the rats were determined. The results showed that the mitochondrial O_2~- generation rate from — Se rats was significantly higher than those from + Se rats at 2 and 3 months. During all the feeding periods, no significant difference in mitochondrial Mn-SOD activity was found between the—Se and + Se groups,while the blood Se concentration in — Se group was significantly lower than those in + Se group at each feeding time and continually decreased in the 2 and 3 month. The results suggested that selenium could depress O_2~- generation in heart mitochondria.