Superoxide dismutase, catalase and glutathione peroxidase activities in maternal and cord blood erythrocytes.

The "antioxidant" enzymes superoxide dismutase, catalase and glutathione peroxidase were assayed in a biological model with low oxygen tension (red cells from cord blood of newborn infants). Catalase and glutathione peroxidase activities in red cells of newborns were significantly lower when compared with their mothers and with normal controls. In contrast, superoxide dismutase activity was unchanged. Thus, normal activities of superoxide dismutase seem to be necessary in order to protect red blood cells from superoxide radicals during foetal life, while even low activities of catalase and glutathione peroxidase are sufficient to protect red blood cells from hydrogen peroxide. No correlation was found between the "antioxidant" enzyme activities present in cord blood erythrocytes and the bilirubin concentrations during the first days of life.