Abstract
Effects of α-glucosidase inhibitor BAY g 5421 on the disaccharidases were studied with rat intestinal brush border membranes and purified sucrase-isomaltase complex (S-I complex) .
Among the disaccharidases in brush border membranes, glucoamylase was the most sensitive, whe reas isomaltase was the most insensitive to BAY g 5421. In an inhibitor concentration of 10μM, the inhibition of glucoamylase was 92.3%, that of sucrase, maltase, and isomaltase was 82.3%, 70.9% and 7.2%, respectively. Kinetic studies revealed that BAY g 5421 inhibited sucrase, isomaltase, and glucoamylase competitively.
Inhibitory effects of BAY g 5421 on the purified S-I complex were similar to those on disaccharidases of brush border membranes.
