Objective: To explore the possible action mechanisms of Zhitong Rushen decoction on ulcerative colitis( UC). Methods: The 40 healthy male SD rats were randomly divided into four groups: normal group,model group,olsalazine group( western medicine group) and Zhitong Rushen decoction group( TCM group),each 10 rats in every group. Except the normal group,the remaining three groups were prepared by TNBS method into animal models of UC rats. After successful modeling,to start with drug intervention. After three weeks of continued medication,the colon tissue of rats were taken in each group,and the I...