EVALUATION OF THE ROLE OF MAST-CELLS IN THE PROGRESSION OF ACETIC ACID-INDUCED COLITIS IN MICE

Background: Mast cells are widely distributed in the gastrointestinal mucosa. However, their role in the pathogenesis of inflammatory bowel disease remains unsettled. The aim of the present study is to clarify the relative importance of mast cells in the progression of acetic aci d-induced colitis in mice. Methods: Mast cell-deficient W/W-nu and the ir normal littermate +/+ mice were given intrarectal administration of 5% acetic acid. The severity of colonic damage, the number of mast ce lls, and myeloperoxidase (MPO) activities in the colonic tissues were examined. Results: The severity of colonic damage Was comparable betwe en W/W-nu and +/+ mice. In both groups of animals kinetic changes of t he severity of the mucosal damage agreed well with that of MPO activit ies in the colonic mucosa. Pretreatment with a mast cell stabilizer, k etotifen, did not affect the severity of colitis in +/+ mice. Conclusi ons: These results discount, but do not disprove, the role of mast cel ls in the progression of acetic acid-induced colitis in mice.