Abstract:

 Objective     To investigate the correlation between type 2 diabetes associated diarrhea and changes of enteric nervous system. Methods     Fourteen patients with type 2 diabetes who underwent colonoscopy for diarrhea symptoms were chosen as the diabetic diarrhea group, ten non-diabetic patients with normal colons underwent colonoscopy for other reasons were elected as the control group. Intestinal mucosa nerve plexus ultrastructural changes were observed by an electric microscope, and structural changes of bowel nerve plexus were observed by using neuron specific protein gene product 9.5(PGP9.5) immunohistochemical method. Results      The colonic mucosa in the diabetic diarrhea group had some changes, such as cavitation of the nerve fiber bundle neuraxial cavity, low density in the cytoplasmic matrix of Schwann cells, and thickening of the membrane of unmyelinated nerve fibers. There was no significant change in the control group. After nerve fibers of the colonic mucosa were marked by PGP9.5， average percentage of the PGP9.5positive area in the epithelium and interstitium of the mucosal plexus in the diabetic diarrhea group was significantly larger than that in the control group ［(4.13±1.12)% vs (2.18±1.01)%，P<0.01］. Conclusion      Type 2 diabetes associated diarrhea may be related to ultrastructural changes of mucosa plexus. The decrease of nerve fibers in submucosal plexus may be involved in the process of diarrhea symptoms in type 2 diabetes.

Key words: Diabetes； Diarrhea； Intestinal mucosa； Ultra-structure； Protein gene product 9.5