Erythrocyte enzymes decomposing reactive oxygen species and gestational age.

Superoxide dismutase (SOD; EC 1.15.1.1), catalase (CAT; EC 1.11.1.6) and glutathione peroxidase (GSH-Px; EC 1.19.1.1) were assayed in erythrocytes from neonates over a range of gestational ages. Both SOD and CAT activities were found to increase, but GSH-Px to decline, with gestational age. Enzyme activities in the erythrocytes of 13 babies who had respiratory distress syndrome (RDS) were not significantly different from controls matched for gestational age, but four with bronchopulmonary dysplasia (BPD) were found to have lower SOD activity. The importance of SOD in the preparation for extrauterine life is substantiated.