Glucose homeostasis in the chicken.

Plasma glucose level and glucose turnover rate were studied in chicks (Gallus domesticus) fed isocaloric diets containing glucose, fructose or soybean oil as the main energy supplement. Plasma glucose level and body weight gain were not affected by glucose intake. Glucose turnover rate decreased from 15.6 to 10.2 mg/(min . kg) in chicks fed glucose- or carbohydrate-free diets, respectively, showing a limited dependence on glucose intake. Glucose conversion to lactate in the intestinal wall in vivo was studied by the introduction of radioactive glucose into a duodenal loop and fractionation of the labeled metabolites in plasma of the duodenal vein and peripheral blood. Up to 37% of the glucose was converted to lactate by the intestinal wall during absorption. Thus, by quenching the perturbations resulting from ingestion and absorption of glucose, the intestine assumes an important role in glucose homeostasis.