Differential Effects of T‐Cell Activation on Gastric and Small Bowel Permeability in Alcohol‐Consuming Mice

BACKGROUND: A number of variables influence the effect(s) of alcohol on distinct segments of the intestine. In these studies, we examined the effect of T-cell activation on gastric and small bowel permeability in alcohol-fed mice. METHODS: Gastric permeability was assessed using sucrose absorption, whereas small bowel permeability was followed using the ratio of lactulose to mannitol absorption and inulin absorption. T cells were activated by injecting antigen OVA(323-339) into DO11.10 T-cell receptor transgenic mice. RESULTS: T-cell activation increased gastric and small bowel permeability through a pathway mediated by interferon-gamma and tumor necrosis factor. In mice that were fed a liquid diet that contained 30% ethanol-derived calories for 2 weeks, T-cell activation increased gastric permeability to levels greater than that observed in solid diet or pair-fed, liquid control diet. By comparison, changes in small bowel permeability induced by T-cell activation were abrogated in alcohol-fed mice. Analysis of intestinal cytokine mRNA levels (interferon-gamma and tumor necrosis factor) indicated that relevant mucosal T-cell function was preserved in alcohol-fed mice. CONCLUSIONS: Overall, these data suggest that alcohol potentiates the effects of T-cell activation on gastric permeability, at the same time blunting effects on small bowel permeability