The effect of ethanol on intestinal L-leucine absorption in rats.

The chronic effect of ethanol on leucine absorption by the whole rat intestine (between duodenum and rectum) was studied using an in vivo multiple-pass perfusion technique. Leucine concentrations in the perfusion medium were 5, 10 and 25 mM respectively in successive passes. Ethanol was administered in drinking water during a one month induction period and then for a four week period of ad libitum ingestion of 30% ethanol solution. The results were compared with ad libitum-fed control rats. The total calorie consumption due to the chow diet plus ethanol increased in the rats which had ingested ethanol when compared with that of the controls. The daily protein intake in ethanol-fed rats was less than that of the controls. No significant differences in morphometric tissue parameters were found between the two experimental groups. Chronic ethanol ingestion provoked a slight (but not significant) decrease in net leucine absorption at 5 mM leucine concentration. In contrast, minor increases in the absorption values were found at 10 and 25 mM leucine concentrations. These findings suggest that the diminished active mechanisms of leucine absorption provoked by ethanol ingestion are compensated for by the enhanced diffusive processes, the passage of the nutrients through the whole intestine, and that the low protein consumption of ethanol-fed rats in ad libitum conditions isn't enough to provoke significant decreases in leucine absorption by the whole intestine.