RESUMEN
Objective @#To compare acute ulcerative colitis (UC) model induced by dextran sulfate sodium ( DSS) at 1. 5% and 3. 0% concentrations and obtain a cost-effective modeling scheme with low mortality．@*Methods@#C57BL /6J mice were randomly divided into control group，1. 5% and 3. 0% DSS group．The mice in control group drank sterilized water and the mice in each group of DSS drank the corresponding concentration of DSS solution，all mice were treated for 7 days．And all mice drank sterilized water on day 8 to 14．The blood stool of mice was ob- served and the disease activity index，the percentage of body weight loss and the percent of survival of mice were calculated on day 1 to 14．Mice were sacrificed on day 8．The spleen index was calculated and the length of colon was measured ; HE staining was used to observe the histopathological changes of colon ; The expressions of tight junc- tion protein Claudin-1 and Occludin in colon tissue were detected by immunohistochemistry ; Immunofluorescence detected the ratio of macrophage in colon tissue ; Levels of tumor necrosis factor-α (TNF-α) in serum and colon tis- sue homogenates were detected by ELISA. @*Results @#Compared with the control group，both mice of 1. 5% DSS group and mice of 3. 0% DSS group showed similar clinical and pathological features to human UC ; The colon lengths were both shortened (P＜0. 01) ; The expressions of Claudin-1 and Occludin in colon tissue both decreased (P＜0. 01) ; Spleen index increased (P＜0. 01) ; The proportion of macrophages in colon tissue increased (P＜0. 01) ; Levels of TNF-α in serum and colon tissue homogenates both increased (P ＜0. 01 ) ．The percent of survival of 1. 5% DSS mice within 14 days was higher than that of 3. 0% DSS mice．@*Conclusion @#The acute UC model can be established efficiently and economically by giving 1. 5% concentration of DSS solution in mice for 7 days.