Objective:To compare the therapeutic effects of Clyster No.1(CN1

the Pulsatillae decoction) with salazosulfapyridine(SASP) to the ulcerative colitis(UC) model induced by dinitrochlorobenzene (DNCB)-acetic acid(AA) in mice

to research the pathogenesis.Methods:KM mice were randomly divided into four groups: normal control group

experimental colitis model group

SASP group and CN1 therapeutic group.Proportions of CD3+、CD4+ T cell、 in mesenteric lymph node and peripheral blood of each group were estimated by flow cytometry;and histological changes were evaluated by HE staining and histological score of intestine.Results: Compared with normal control group

the histological score was markedly higher and the length of colon became shorter in model group of experimental colitis.The proportion of CD3+、CD4+ T cells were markedly decreased(P<0.01) in model group compared with the control group.After two weeks' treatment with SASP and CN1

the histological score was reduced

the length of colon recovered almost to normal level

accompanied with increasing in the proportion of CD3+、CD4+ T cells compared with the model group.Conclusions: The effect was satisfactory for the UC mice treated with CN1 and it may serve as a tool for investigation of the pathogenesis and therapeutical effect for UC.