In view of the critical role of 5-HT signalling in the generation of intestinal inflammation, [10], [18] and the connection of IL-13 in pathogenesis of IBD, specifically of UC, in the present study we investigated the role of IL-13 in the pathogenesis of colitis in the context of gut 5-HT production in two different models of experimental colitis [dextran sodium sulfate (DSS) and dinitrobenzenesulfonic acid (DNBS)]. The gene discussed is IL13; the disease is inflammatory bowel disease.