Influence of Dietary Composition on the Capacity of Glucose Formation in Liver of Rats

Abstract

The influence of the levels of dietary carbohydrate, protein, and fat on the capacity o1 glucose formation in liver slices and on the activities of gluconeogenic and glycolytic enzymes in the liver of rats were investigated. Incorporation of radioactivity from pyruvate-3-¹⁴C into glucose by liver slices not only increased in carbohydrate deficient groups, but also was affected by fat content of diets. PEPCK, FDPase, and G6Pase of rat liver were affected by the levels of dietary carbohydrate. Moreover, PEPCK and FDPase were increased by increasing the protein content of diets and G6Pase was increased by increasing the fat content of diets. The ratios PEPCK/PK and G6Pase/GK were increased significantly by decreasing the carbohydrate content of diets, but the ratio FDPase/PFK did not show any significant change among dietary groups. From these experiments, it was concluded that the capacity of glucose formation in the liver of rats was changed by carbohydrate and fat content of diets and changes in gluconeogenic capacity with diets were correlated with changes in G6Pase activity.