Figure 1: Pathological change of control group, UC model group, and rosiglitazone treatment group on day 14 under light microscope (HE×200). The colonic mucosa structure was intact in the control group. Mucosa and submucosa defects could be seen with infiltrations of inflammatory neutrophils and lymphocytes in the lamina propria of the model group on day 14. The degree of mucosal inflammation relieved in the rosiglitazone treatment group on day 14. Regenerated epithelia covered the surface of ulcer and the mucosa tended to be complete. The base of ulcer was filled with tissues and scars.