Transport of monosaccharides by the small intestine of genetically diabetic mice

Small intestinal absorptive function was investigated in genetically diabetic mouse model (C57 BL/KSJ dbm) in order to determine the long-term effects of genetic and uncontrolled diabetes mellitus on intestinal function. Initial rates of uptake of nonmetabolizable glucose analogs, beta-methyl-D-glucoside and 3-O-methyl-D-glucose were determined in diabetic mice and their littermate controls using everted sacs from proximal and distal halves of the intestine. In addition, intestinal weight, intestinal length, mucosal protein, and DNA were measured. There were no significant differences between controls and diabetics in rates of uptake by either proximal or distal segments. Kinetic characteristics of uptake, Km and Vmax, were similar in controls and diabetics. These results clearly demonstrate that intestinal transport of monosaccharides is not altered in genetic diabetes, and therefore are in contrast to augmented transport reported in the early phase of drug-induced diabetes but similar to the results observed in chronic drug-induced diabetes. However, diabetic mice exhibited stimulated intestinal growth similar to rats with chronic drug-induced diabetes.