The Effect of Triglycerides on Gluconeogenesis and Ketogenesis in the Isolated Perfused Rat Liver ∗

Abstract

Summary

Glucose and ketone body production was measured in livers from 24 hr starved rats perfused with 20 mM lactate. Addition of either tributyrin (1.5 mM) or Ediol (5 mM) to the perfusate markedly increased both glucose and ketone body production. Addition of theophylline (10 mM) further increased glucose and ketone body production in the presence of triglyceride. Glucagon (1 μg/ml) resulted in an increase in ketone body production with either triglyceride present, but glucose production was not increased over that observed with glucagon alone. Glucose production, when both glycerol (20 mM) and lactate were present, was greater than that observed with either substrate alone. Intracellular hydrolysis of triglycerides may contribute to glucose formation directly by the conversion of glycerol to glucose and indirectly stimulate gluconeogenesis by the effects of fatty acids and their metabolites on glucose formation from lactate or pyruvate.