Electrical properties of the intestinal mucosa of the chicken and the effects of luminal glucose

Transmural potential difference (PD), short-circuit current (Isc), and elec trical resistance (R) were measured in the isolated mucosa of the duodenum, jejunum, ileum, proximal cecum, and rectum in order to characterize the el ectrical properties of the chicken small and large intestine. The chicken i ntestine was classified into three categories, regarding its electrical cha racteristics: 1) the duodenum, with four to five times higher R than the ot her segments and the lowest PD; 2) the group formed by the jejunum, the ile um, and the proximal cecum, with high PD and low R; 3) the rectum, with low PD and low R. In all segments, the addition of D-glucose into the luminal side stimulates Isc, and this effect can be reversed by phloridzin, indicat ing that the glucose-induced Isc increase is due to Na+-D-glucose cotranspo rt. The effect of glucose is maximal in the rectum, with a fivefold Isc inc rease, suggesting that this segment may have an important rule in the absor ption of Na+ as well as of nutrients co-transported with Na+.