Objective To study the inhibitory effect of RNA interference (RNAi) on bcl-2 expression of vascular smooth muscle cells （VSMCs) in rabbit. Methods The expression vector of bcl-2 gene-targeting small interference RNA (pshRNA-bcl-2) was constructed and was transfected into VSMCs by lipofectamine, and the unloaded vector was used as control. The expression of bcl-2 mRNA was identified by RT-PCR and Western blot, respectively. The growth of the transfected VSMCs was examined by MTT. Results The pshRNA-bcl-2 may inhibit the expression of bcl-2 gene at the levels of transcription and translation. There were significant differences (P＜0.01) of the expressions of bcl-2 mRNA between the VSMCs that were transfected with pshRNA-bcl-2 and the ones in plasmid transfected group and control group, respectively. There was a significant difference (P＜0.01) in the growth of VSMCs between the plasmid transfected and the control groups. Conclusion The plasmid containing the small interference RNA of bcl-2 may have an inhibitory effect on the cell growth and endogenous expression of bcl-2 gene at the levels of transcription and translation in VSMCs.
