AIM: To investigate the inhibition effects on the productionof collagen type I, Ⅲ secreted by activated rat hepatic stellatecells (rHSCs) by antisense tissue inhibitors of metalloproteinase1 (TIMP-1) recombinant plasmid through elevating interstitialcollagenase activity.METHODS: rHSCs were extracted from normal rat liverby pronase and collagenase digestion and purified bycentrifugal elutriation, and were cultured on plastic dishesuntil they were activated to a myofibroblastic phenotypeafter 7-10 days. RT-Nest-PCR and gene recombinanttechniques were used to construct the rat antisense TIMP-1 recombinant plasmids which can express in eucaryoticcells. The recombinant plasmid and the pcDNA3 emptyplasmid were transfected in rHSCs by Effectene (QIAGEN)separately. Cells were selected after growing in DMEMcontaining 400 μg/ml G418 for 2-3 weeks. Expression ofexogenous gene was assessed by North blot, andexpression oflIMP-1 in rHSCs was determined by Northblot and West blot. We tested the interstitial collagenaseactivity with FITC-labled type I collagen as substrate.Ultimately, we quantified the type Ⅰ, Ⅲ collagen byWest blot.RESULTS: The exogenous antisense TIMP-1 recombinantplasmid could be expressed in rHSCs well, which couldblock the expression of TIMP-1 greatly, the ratio of TIMP-1/GAPDH was 0.67, 2.41, and 2.97 separately at mRNAlevel (P＜0.05); the ratio of TIMP-1/β-actin was 0.31, 0.98and 1.32 separately at protein level (P＜0.05); It mightelevate active and latent interstitial collagenase activity,the collagenase activity was 0.3049, 0.1411 and 0.1196respectively. (P＜0.05), which led to promotion thedegradation of type Ⅰ, Ⅲ collagen, the ratio of collagen I/β-actin was 0.63, 1.78 and 1.92 separately (P＜0.05); andthe ratio of collagen Ⅲ/β-actin was 0.59, 1.81 and 1.98separately (P＜0.05).CONCLUSION: These data shows that the antisense TIMP-1 recombinant plasmid has the inhibitory effects on theproduction of type Ⅰ, Ⅲ collagens secreted by activatedrHSCs in vitro. It could be a novel method to reverse hepaticfibrosis in the future.