[Lipoperoxidation and antioxidant substances in the human placenta during gestation].

Recently particular interest has been shown in the relationship of the aging phenomenon to lipid peroxidation by free radicals. We studied changes in lipid peroxidation in the human placenta by measuring lipoperoxides from early pregnancy to term. In addition, we studied changes in the activities of superoxide dismutase, catalase, glutathione peroxidase and the concentration of alpha-tocopherol in the placental tissues. The degree of lipid peroxidation in placental tissue in early pregnancy was significantly higher than that in late pregnancy. Lipid peroxidation in the case of spontaneous abortion was slightly higher than that in normal pregnancy. The activities of SOD and catalase increased significantly, but glutathione peroxidase activity remained almost the same throughout development. On the other hand, the alpha-tocopherol concentration decreased gradually as gestation progressed. These results suggest that early placental tissue is functionally immature, then gradually suppresses lipoperoxide formation as pregnancy advances. The placental tissue protects the fetus from many kinds of radicals in the feto-maternal circulation.