Interactions in vivo between oxidation of non-esterified fatty acids and gluconeogenesis in the newborn rat

Publisher Website
Google Scholar
Abstract
Metabolic interactions between fatty acid oxidation and gluconeogenesis were investigated in vivo in 16 h old newborn rats under various nutritional states. As the newborn rat has no white adipose tissue, starvation from birth induces a low rate of hepatic fatty acid oxidation. Hepatic gluconeogenesis is inhibited in the starved newborn rat when compared with the suckling rat, which receives fatty acids through the milk, at the steps catalyzed by puruvate carboxylase and glyceraldehyde 3-phosphate dehydrogenase. These inhibitions are rapidly reversed by triacyglycerol feeding. Inhibition of fatty acid oxidation by pent-4-enoate in the suckling animal mimics the effect of starvation on the pattern of hepatic gluconeogenic metabolites. In newborn rat in vivo, hepatic fatty acid oxidation can apparently increase the gluconeogenic flux by providing the acetyl-CoA necessary for the reaction catalyzed by pyruvate carboxylase and the reducing equivalents (NADH) to displace the reversible reaction catalysed by glyceraldehyde 3-phosphate dehydrogenase in the direction of gluconeogenesis.