Abstract: Objective To observe the effect of Minor Bupleuri Decoction in the pathological changes of mice bearing Lewis lung cancer cells.Methods Inoculated the thirty-eight mice with Lewis lung cancer cells, after five days choosing successful tumor-bearing mice, then they were randomly divided into three groups:Model group(MG), Minor Bupleuri Decoction group(BG)and Shenyi Capsule group(SG), 10 mice in each group.Different doses of drug were given to four group:Normal sodium, Minor Bupleuri Decoction and Shenyi Capsule liquid at 0.4mL once a day by gastrogavage.To observe the tumor growing status, HE staining was used to observe the pathological changes of tumorous tissue.Results (1)The BG & SG inhibited the growth of tumor, the weight of tumors were much lower than that of the MG, and there were significant differences compared with the MG(P＜0.01), but no difference between the BG & SG(P＞0.05).(2)Compared with the MG, there were some cell morphological changes of the BG & SG.Such as the volume of some tumor cells became small and the abnormal cells became less, the cell nuclei were tightening, the chromatin were condensed in margin, and the shape of splitting nuclei reduced obviously.Conclusion The Minor Bupleuri Decoction has effect on inhibiting the proliferation of Lewis lung cancer cells.

Key words: Minor Bupleuri Decoction, Lewis lung cancer cells, Pathomorphology