Enhancement of Insulin Binding and Glucose Transport by Acarbose in Adipocytes of Zucker Rats

Abstract

Acarbose (BAY g 5421) is an intestinal α-glucosidase inhibitor which slows carbohydrate digestion and the rate of glucose absorption from the gut. To test whether longterm administration of acarbose alters adipose tissue sensitivity to insulin, adult male obese and lean Zucker rats were fed 30 mg acarbose/100 g of chow or chow alone (control) for a 15-week period. At sacrifice, epididymal fat pads were removed, and isolated adipocytes were prepared by collagenase digestion. Equilibrium binding of A-14 ¹²⁵I insulin, and transport of trace U-[¹⁴C]glucose were determined with adipocytes incubated for 50 min at 37 °C in concentrations of unlabeled insulin from 0 to 16000 pM. Values for specifically bound insulin were corrected for nonspecific binding and for the volume occupied by the cells.