EXPRESSION OF BRUSH-BORDER ENZYMES IN ETHANOL-FED RAT INTESTINE

The effect of feeding ethanol daily for 40 days was studied on various brush border enzymes in rat intestine. Brush border alkaline phosphat ase (AP), lactase, gamma-glutamyltranspeptidase (gamma-GTP), p-nitroph enyl (PNP)-beta-D-galactosidase (P < 0.01) and sucrase (P < 0.001) wer e significantly enhanced while leucine aminopeptidase and PNP-beta-D-g lucosidase activities were unaltered in ethanol fed rats compared to t he controls. Kinetic studies revealed that an increase in Vmax togethe r with a decrease in affinity in case of gamma-GTP and an increase in Vmax for AP and sucrase were responsible for the observed stimulation of enzyme activities in ethanol administered rats. Significant changes in enzyme activities were observed in different populations of entero cytes along the crypt-villus unit in the ethanol fed animals. These ob servations suggest that ethanol feeding modifies the brush border enzy mes in rat intestine but the underlying mechanisms seem to be distinct in differentiating enterocytes.