ABSTRACT
Objective Zinc sulfate has anti inflammatory action in many animal models, however, the effects of zinc in colitis remained uncertain. The present study was to evaluate the role of zinc sulfate in experimental colitis and probe into its underlying mechanisms. Methods Colitis was induced by administrating 2,4,6 trinitrobenzenesulphonic acid (TNB) rectally in Spragur Dawley female rats. Beginning at the first day of TNB colitis, the rats were treated with zinc sulfate enema once daily for 6 days. The rats were sacrificed at days 8. The effects of zinc sulfate were evaluated by examining mucosal lesion area, mucosal myeloperoxidase (MPO) and superoxide dismutase (SOD) activities, mucosal prostaglandin E 2(PGE 2) and leukotriene B 4(LTB 4) levels. Results TNB induced severe colitis as evidenced by increased mucosal lesion area, mucosal MPO activity and PGE 2 and LTB 4 levels. Six days after the application of the zinc sulfate enema, the mucosal lesion area, MPO activity, PGE 2 and LTB 4 levels were all decreased significantly, except mucosal SOD activity that was remained unchanged after zinc treatments. Conclusions The data suggest that zinc sulfate enemas have an anti inflammatory action on experimental colitis through the mechanism other than increasing SOD activity.