Enteroendocrine cells and 5-HT availability are altered in mucosa of guinea pigs with TNBS ileitis

Publisher Website
Google Scholar
Abstract
Enteroendocrine cells act as sensory transducers, releasing 5-HT and numerous peptides that are involved in regulating motility, secretion, and gut sensation. The action of mucosal 5-HT is terminated by a 5-HT reuptake transporter (SERT). In this study, we examined the hypothesis that ileitis leads to changes in enteroendocrine cell populations and mucosal 5-HT availability. Ileitis was induced in guinea pigs by intraluminal injection of 2,4,6-trinitrobenzenesulfonic acid and experiments were conducted 3, 7, and 14 days after treatment. The number of somatostatin, neurotensin, and 5-HT-immunoreactive cells increased at 3 and 7 days of ileitis, respectively, whereas no significant changes in the numbers of cholecystokinin, glucagon-like peptide-2, glucose-dependent insulinotropic peptide, and peptide YY-immunoreactive cells were observed. Chemical stimulation of the inflamed mucosa with sodium deoxycholic acid significantly increased 5-HT release compared with basal release. Mechanical stimulation of the mucosa potentiated the effect of the chemical stimuli at day 7 . Epithelial SERT immunoreactivity was significantly reduced during the time course of inflammation. Thus changes in enteroendocrine cell populations and 5-HT availability could contribute to the altered motility and secretion associated with intestinal inflammation by disrupting mucosal signaling to enteric nerves involved in peristaltic and secretory reflexes.