GLUTATHIONE-DEPENDENT ANTIOXIDANT ENZYME-ACTIVITIES AND GLUTATHIONE CONTENT IN THE RAT-BRAIN AT DIFFERENT STAGES OF ESTROUS-CYCLE

Enzymatic activities of glutathione peroxidase, glutathione-S-transfer ase, glutathione reductase and catalase, as well as the glutathione co ntent were measured in the brain tissue of regularly cycling rats at d ioestrus, proestrus and estrus. The activity of glutathione peroxidase was found to be suppressed at proestrus, whereas that of catalase was increased at dioestrus. Glutathione transferase and glutathione reduc tase activities, as well as the glutathione content appeared to be sta ble during the oestrous cycle. These results suggest that, in the fema le rat, glutathione peroxidase and catalase activities in the brain ti ssue are influenced by the ovarian hormone status.