Evaluation of Lipid Peroxide Metabolism in Neonatal Rats during Suckling: Developmental Changes in Whole Body Lipid Peroxides.

Abstract

SummaryTo evaluate lipid peroxide metabolism in neonatal rats during suckling, we studied developmental changes in whole body lipid peroxidation by measurement of thiobarbituric acid-reactive substances (TBARS) determined as malondialdehyde. Whole body TBARS contents were very low immediately after birth but increased sharply at 3-9 days, peaked at 9-15 days, and then remained unchanged until 21 days. The feeding of a skimmed milk diet to neonates between 17 and 20 days old sharply decreased their whole body TBARS contents at 20 days as compared with those at lb days, however, this was not observed by the feeding of an artificial milk diet containing 3 g of soybean oil/ 100 g diet. In vitro ethane production by liver and brain homogenates and in vivo breath ethane levels in expired air were higher at 20 or 21 days than at 10 days after birth. These results suggest that lipid peroxide formation in neonatal rats increases shortly after birth and that its degradation and/or excretion may increase during the latter period of suckling.