Ketone body metabolism during development.

This paper briefly reviews the role of ketone bodies during development in the rat. Regulation of ketogenesis is in part dependent on the supply to the liver of medium- and long-chain fatty acids derived from mother's milk. The partitioning of long-chain fatty acids between the hepatic esterification and oxidation pathways is controlled by the concentration of malonyl-CoA, a key intermediate in the conversion of carbohydrate to lipid. As hepatic lipogenesis is depressed during the suckling period, [malonyl-CoA] is low and entry of long-chain acyl-CoA into the mitochondria for partial oxidation to ketone bodies is not restrained. Removal of ketone bodies by developing tissues is regulated by their availability in the circulation and by the activities of the enzymes of ketone body utilization. The patterns of activities of these enzymes differ among tissues during development so that the neonatal brain is an important site of ketone body utilization. The major role of ketone bodies in development is as an oxidative fuel to spare glucose, but they can also act as lipid precursors.