Changes in hepatic carbohydrate metabolism after jejunoileal bypass.

The effect of 90% jejunoileal bypass procedure on liver enzymes was evaluated in 11 obese Zucker fat rats after a 50% weight loss. Control tissues were also collected from 11 unoperated obese rats. In the jejunoileal bypass group, there was a significant decrease in phosphofructokinase, pyruvate kinase, and glucose-6-phosphate dehydrogenase activities. Pyruvate carboxylase, alanine aminotransferase, and lactate dehydrogenase activities were not altered. Fructose 1,6-biphosphatase, aldolase, aspartate aminotransferase, and phosphoenolpyruvate carboxykinase activities were increased in the jejunoileal bypass group. These studies suggest that after jejunoileal bypass glycolysis is reduced and gluconeogenesis is increased. Amino acids may provide an essential energy source for hepatic function.