The effect of experimental colitis on alanine absorption and the expression of its transporters in the small intetsine in adult rats

Abstract

The aim of this research project is to study the effect of experimental colitis on jejunal alanine absorption and the expression of its transporters in the small intestine using two colitis-inducing agents (TNBS and IA) at two different time points (2 and 7 days for IA; 2 and 8 days for TNBS). The rate of alanine absorption was examined by the in vivo single pass perfusion technique in the jejunum, and the mRNA level of expression of alanine transporters was determined in the small intestine via real time PCR. The results have shown a significant decrease in the absorptive capacity for alanine in the jejunum in both models of experimental colitis. In addition, a significant decrease in the level of mRNA expression of alanine transporters, SLC6A19, ASCT2, and LAT2, was shown in the small intestine in both experimental colitis models. No variation was seen in the level of mRNA expression of SLC6A14. The present research suggests that a cross-talk is present between the inflamed colon and the small intestine, thereby influencing the absorptive capacity of the small intestine for alanine. Recent evidence indicates that this cross-talk may be controlled by a neural and/or an immunological mechanism.