INTRAERYTHROCYTE NONPROTEIN-BOUND IRON AND PLASMA MALONDIALDEHYDE IN THE HYPOXIC NEWBORN

Intraerythrocyte nonprotein-bound iron (INPBI), malondialdehyde (MDA), and hypoxanthine plasma levels (HxPL), were determined by high-pressu re liquid chromatography in 138 randomly selected newborn infants with gestational ages ranging from 23 to 42 weeks at birth and on fourth d ay of life. MDA plasma levels were significantly higher in cord and fo urth-day blood samples of preterm babies than term infants as well as babies born by emergency Caesarean section than babies born by vaginal delivery and in intubated than in nonintubated newborns. Highly signi ficant correlations both in cord blood and fourth-day blood samples we re observed between MDA plasma levels and gestational age, birth weigh t, Apgar score at 1 min and 5 min, HxPL, pH, base deficit, and INPBI c ontent. Multiple regression analysis identified HxPL as the best singl e predictor of MDA plasma levels in cord blood, and INPBI content in f ourth-day blood as the best single predictor of MDA plasma levels in f ourth-day blood. The results indicate that red cells and plasma lipopr oteins are a common target of free radical-induced oxidative stress du ring hypoxia. (C) 1998 Elsevier Science Inc.