Pulmonary antioxidant enzyme maturation in the fetal and neonatal rat. I. Developmental profiles.
Neonatal, adult, and fetal rat lungs of 18, 20, and 22 d gestation from four to six litters were examined for cytochrome oxidase, glucose-6-phosphate dehydrogenase, catalase, glutathione peroxidase, copper-zinc and manganese superoxide dismutase activities. All results were corrected for the contribution of enzymes in blood that contaminate homogenates. Because lung protein/DNA ratios and body water change significantly with gestational age, enzyme activities were expressed as U/mg DNA. All activities were low in d 18 lung and increased with advancing gestational age. Only catalase and copper-zinc superoxide dismutase increased activity in response to air breathing, suggesting that maturation of the antioxidant enzyme system is virtually complete before delivery. Activities of glucose-6-phosphate dehydrogenase, catalase, glutathione peroxidase, and manganese superoxide dismutase were higher in neonatal than in adult lung.
D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D003300:Copper / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000378:metabolism; D005260:Female; D005333:Fetus / Q000201:enzymology*; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D008168:Lung / Q000196:embryology / Q000201:enzymology*; D008297:Male; D008345:Manganese / Q000378:metabolism; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D013482:Superoxide Dismutase / Q000378:metabolism; D015032:Zinc / Q000378:metabolism
D008345:Manganese; D003300:Copper; D005954:Glucosephosphate Dehydrogenase; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D003576:Electron Transport Complex IV; D015032:Zinc