Establishment of dextran sulfate sodiumª²induced ulcerative colitis model in rats

    ZHAO Ping, DONG Lei, LUO Jinª²Yan, MA Hui, GUAN Haiª²Tao, SHANG Heª²Ling

    1Department of Gastroenterology, 2Department of Oncosurgery, Second Hospital, Xi¡¯an Jiaotong University, Xi¡¯an 710004, China, 3Tangyu Convalescent Hospital, Lantian 710516, China

    ¡¾Abstract¡¿ AIM: To establish the rat model of ulcerative colitis (UC). METHODS: The rats were first given 40 g/L dextran sulfate sodium (DSS) in drinking water for 7 d and then given only water for 10 d. The disease activity index (DAI) of all the rats was evaluated daily. The rats were killed on day 8, 13 and 18 and the lesion score and histological score of colon were evaluated. Segments of distal colon were adequately prepared for transmission electron microscopic observations. The weight index of cecum, colon, thymus and spleen were calculated and the myeloperoxidase (MPO) activity of rectum was measured. RESULTS: Rats receiving 40 g/L DSS solution for 7 d developed diarrhea and positive fecal occult blood. Inflammation of colon mainly involved the mucous membrane and submucosa. Focal erosions of the epithelium, goblet cells depletion, destruction of crypt and neutrophil infiltration were observed. The increase of MPO activity [(8.84¡À3.67) nkat/g tissue vs (127.19¡À27.84) nkat/g tissue, P<0.01] and weight of spleen [(3.45¡À1.00) mg/g vs (5.07¡À1.31) mg/g, P<0.05] was also observed. After replacing the DSS solution with water, the symptoms and colonic pathological changes of rats were gradually disappeared and the MPO activity significantly decreased(P<0.05). CONCLUSION: This colitis model in rats appears to share nearly all the morphological characteristics with human UC. ......