Inhibition of Tissue Factor Gene Expression With Chemically Synthesized Small Interfering RNA in Rats' Vascular Smooth Muscle Cells

Objective:To investigate the feasibility and efficacy of tissue factor(TF)gene silencing in rats'vascular smooth muscle cells (VSMCs)by using chemically synthesized small interfering RNA(siRNA). Methods:Double-stranded 25 bp-RNA molecules targeted at sequences within the rats'TF gene were designed and constructed .Primary rats'VSMCs were cultured with either TF siRNA or control siRNA.Transfection efficacy was determined by fluorescence microscopy,the mRNA expression of TF was analyzed by RT-PCR,and the protein expression was examined by Western blot and immunohistochemistry after stimulation with platelet-derived growth factor(PDGF)-BB. Result:Successful siRNA transfection of VSMCs was confirmed by fluorescence microscopy,and the transfection efficiency was about 90±2.3%.Cells transfected with the highest effective siRNA from one of three candidate sequences showed a reduction of 86±0.6%in TF mRNA expression at 24h after transfection,and a reduction of 92±1.0%in TF protein expression at 48h after transfection compared with untransfected cells,at the same time,TF positive staining was markedly decreased after transfection. Conclusion:TF expression could be effectively silenced by RNA interfering in VSMCs from rat aorta.