Our study investigated the effect of N-acetylglucosamine (GlcNAc) on the intestinal mucosal barrier function in rats. Rats were randomly assigned into normal control group, diarrhea-predominant irritable bowel syndrome (IBS-D) group and GlcNAc group. IBS-D was introduced into the IBS-D group without any treatment. The GlcNAc group were treated with GlcNAc. Microvilli and tight junctions of intestinal epithelial cells were detected. The D-lactic acid level and diamine oxidase (DAO) activity in the serum were determined. Compared with normal rats, microvilli were sparsely distributed on the intestinal epithelial cells, the tight junction gap also widened, and D-lactic acid level and DAO activity were significantly higher in the IBS-D group. After GlcNAc treatment, the microscopic structure of the intestinal mucosa became largely normal, and the level of D-lactic acid and the DAO activity were lowered. In conclusion, GlcNAc can effectively improve the intestinal mucosal barrier dysfunction, perhaps through enhancing the cellular metabolism.

Objective To study the influencing factors on the establishment of the bacterial cryptic growth cell(CGC)-related IBS rat model.Methods The two-steps stimulation method was used to establish IBS rat model,which were first stimulated to produce CGC by different concentration combinations of cefuroxime sodium,and then stimulated by the chili liquid.The CGC colonization,fecal water content and frequency of defecation were employed as the indexes of model establishment.Results The stimulation by different concentration combinations of cefuroxime sodium caused different characteristics of the CGC dynamic changes and colonization rates of rats.The ratio of male to female of successful creation IBS model rats was 1.5∶ 1.Conclusion Cefuroxime sodium concentration combination plays a critical role in the dynamic changes and colonization of CGC during the establishment of CGC-related IBS rat model,and the establishment of the animal model showed gender differences,which is of great significance in the study of IBS pathogenesis and the gender differences.