A DNBS-Induced Model Of Ulcerative Colitis In Rats And The Therapeutic Effect Of UTI On The Model

Objects To build a new model of ulcerative colitis(UC), to study the relation between protease activity in the tissue of UC and the pathogenesis of UC, and to evaluate the therapeutic effect of urinary trypsin inhibitor(UTI) on experimental UC.Methods The experimental UC was induced in Wistar rats by enema with dinitrobenzenesulfonic acid (DNBS) and ethanol. Protease activity present in colonic tissue was determined on gelatin zymograms. We treated the experimental UC by injecting UTI into the rats through the caudal vein.Results Make a comparison between the model of UC and human UC, we fond surprisingly they resembled each other in symptoms, gross appearance and histopathology. The protease activity present in colonic tissue of experimental UC was increased greatly compared with the controls.However, the protease activity was decreased obviously after we cured the rats with UTI , and moreover, the symptoms of UC and gross appearance were also improved, but the histopathology was not meliorated significantly. Conclusions Firstly, the DNBS-induced model of UC in rats is similar to human UC, and has many advantages such as it can be replicated easily, has smaller toxicity and can be acquired cheaply. Secondly, proteases play an important role in pathogenesis of UC. Finally, UTI can decrease the protease activity of UC tissue and show a primary curative effect on experimental UC.