CHANGES IN ACTIVITIES OF SUPEROXIDE-DISMUTASE AND LIPID PEROXIDE IN CORPUS-LUTEUM DURING PREGNANCY IN RATS

Activities of superoxide dismutase (SOD) and lipid peroxide (LPO) were studied in corpora lutea of pregnant rats. SOD activities, both Mn-SO D and Cu,Zn-SOD, gradually increased in the corpora lutea until day 15 of pregnancy and decreased thereafter until day 21 of pregnancy, in a similar manner to serum progesterone concentration. LPO activities re mained low until day 15 of pregnancy, but increased rapidly after day 15 to day 21 of pregnancy. Incubation of the dispersed luteal cells fr om day 15 of pregnancy in vitro showed that FeSO4 and ascorbic acid, w hich induce lipid peroxidation, significantly inhibited progesterone s ecretion. The inhibitory effects of FeSO4 and ascorbic acid were block ed by the simultaneous addition of a-tocopherol. These results suggest important roles for SOD and LPO in regulating luteal function during pregnancy.