Abstract: Objective To investigate the effect of intestinal flora from children with Irritable Bowel Syndrome (IBS) on intestinal motility and acid-sensitive ion channel expression in mice. Methods Fecal samples of children with IBS identified according to Rome Ⅳcriteria and healthy children were collected and made into fecal microbiota solution. A pseudo-aseptic mouse model was established, mice were randomly divided into two groups:the control group was given fecal microbiota solution of healthy children,and the experimental group was given fecal microbiota solution of IBS children. The intestinal propulsion rate was measured, Serum Motilin (MOT) and Gastrin (Gas) were determined by ELISA, the expression and distribution of ASICs in intestinal tissues of mice were determined by immunohistochemistry. Results Compared with the control group, intestinal propulsion rate, serum MOT and Gas level were significantly reduced in the experimental group (P＜0.05), the expression of ASIC3 in the small intestine and colon of mice from experimental group was significantly increased (P＜0.05);the expression of ASIC3 in small intestine and colon was negatively correlated with the intestinal propulsion rate (P＜0.05). Conclusions Intestinal flora of children with IBS can promote the expression of ASIC3 in intestinal tissue of mice, and the effect of intestinal microorganism on intestinal motility may be related to the activation of ASICs.

Key words: irritable bowel syndrome, intestinal flora, acid-sensitive ion channels, gastrointestinal motility