Objective: The purpose of this study is to study the inhibition of emodin on rabbit aortic smooth muscle cell proliferation(CCC-SMC-1) and on gene expression of cathepsin D

K. Method: In a 2×104/mL density vaccination cells

the experiment was divided into seven groups

including 0.01

0.05

0.1

0.15

0.2

0.25 mmol · L-1of emodin groups

control group. Cells in each group were cultured for 24 h(n=6). The rabbit aortic smooth muscle cells was cultured

to observe emodin on rabbit aortic smooth muscle cell proliferation was determined by MTT method.The impact of emodin on gene expression of relative amount of cathepsin K (Cat K) and cathepsin D (Cat D) of rabbit aortic smooth muscle cells was assayed with PCR. Result: MTT result suggested that emodin had the inhibitition effect on rabbit aortic smooth muscle cell proliferation when the concentration was in the range of 0.05-0.25 mmol · L-1. The 50% inhibitory concentration(IC50)was 0.1 mmol · L-1. The results of PCR showed that the expression of Cat K and Cat D gene in emodin groups was significantly increased (P< 0.05) after 24 h compared with control cells. Conclusion: Emodin can inhibit the proliferation of CCC-SMC-1 cells

the mechanism of which may be related to up-regulation of the gene of Cat K and Cat D expression.