Abstract: Objective To screen RNA interference（RNAi）targets on connective tissue growth factor（CTGF） and tissue inhibitor of metalloproteinase-1（TIMP-1）in vitro. Methods Three candidates RNAi targets for rat's CTGF and TIMP-1 gene were designed and the double-stranded RNA（dsRNA）were synthesized. Then，single or different combined dsRNAs were transfected into rat hepatic stellate cells（HSCs）activated by TGF-β1.The procol-α1，CTGF and TIMP-1 mRNA were detected by fluorescent quantitative PCR，and hepatic fibrosis indexes in HSC supernatant were detected by radioimmunoassay. Results The CTGF mRNA and procol-α1 mRNA were inhibited at 68.09% and 65.03%，respectively in CTGF-3 group when single RNAi targeted on CTGF gene was used，and the TIMP-1 mRNA and procol-α1 mRNA were inhibited at 68.55% and 62.84%，respectively in TIMP-1-3 group when single RNAi targeted on TIMP-1 gene was used；When double RNAi targeted on CTGF gene and TIMP-1 gene were used，the CTGF mRNA and TIMP-1 mRNA were inhibited at 76.60% and 79.03%，respectively in CTGF-3/TIMP-1-3 group，while CTGF-2/TIMP-1-3 group had the most effective effect on inhibiting procol-α1 mRNA with inhibition rate of 85.79%. Conclusion The most effective RNAi targets on CTGF and TIMP-1 were selected successfully and the double RNAi targeting on CTGF and TIMP-1 were stronger than any single RNAi.

Key words: Hepatic fibrosis, Connective tissue growth factor, Tissue inhibitor of metalloproteinase-1, Hepatic stellate cell, RNA interference