HEPATIC-METABOLISM OF MEAL-FED RATS - STUDIES INVIVO AND IN THE ISOLATED PERFUSED LIVER

Hepatic metabolic fluxes (glycolysis, glucose release, glycogenolysis, oxygen consumption, ketogenesis and gluconeogenesis), hepatic glycogen and food ingestion in meal-fed rats were measured and compared to appropriate controls. The following results were obtained: 1) in livers from meal-fed rats a higher fraction of glucosyl units derived from glycogen is used in glycolysis instead of being released in the form of glucose; 2) the rate of glycogen catabolism in livers from meal-fed rats is less than expected when one compares their glycogen levels with those of the appropriate controls; 3) the livers from meal-fed rats become much less ketotic than the livers from rats which were not trained to eat a single meal daily. It was concluded that the liver of meal-fed rats is well adapted to the main characteristics of those animals, e.g., increased lipogenesis from glycolysis products and a reduced need for carbon units from the liver (glucose and ketone bodies) as a consequence of enhanced food intake. © 1990.