Dietary protein regimens and chronic ethanol administration effects on sodium- and proton-dependent solute uptake in rat intestine.

The effect of feeding ethanol daily for 40 days has been studied on intestinal uptake of glucose, glycine, and leucine in rats fed control, 8% protein (LP), and 30% protein (HP) diets. Na(+)-dependent uptake of glucose and glycine both at pH 7.2 and pH 5.5 was significantly depressed (p < 0.001) in ethanol or LP diet-fed animals and remained unaffected in HP-fed rats compared to the controls. But ethanol administration to protein-malnourished rats enhanced the Na(+)-linked glucose and glycine uptakes. Leucine uptake remained unaffected under these conditions. Glucose uptake remained unaltered whereas glycine uptake was reduced when ethanol was administered to rats given HP diet. In the absence of Na+, uptake of glucose, glycine, and leucine was more at acidic pH compared to that at pH 7.2 under all the experimental conditions investigated. Proton-linked uptake of solutes was unaffected by feeding ethanol, LP, or HP diet in rats. Thus, chronic ethanol feeding specifically depresses the Na(2+)-dependent uptake of glucose and glycine. Dietary protein content modifies ethanol effects on intestinal solute uptake in rats.