AIM:To investigate the effects of hepatocyte growth factor (HGF) on MMP-2 expression in scleral fibroblasts from guinea pig with LIM.METHODS:Sixty 1-week-old guinea pigs were chosen for the study. The right eyes were treated with -10.0 D lenses as the LIM group; the left eyes remained untreated as the control group. The refraction and axial length were measured by streak retinoscopy and A-scan ultrasonography respectively prior to and 4 weeks after the experiment. Four weeks later, the guinea pigs were sacrificed and primary scleral fibroblasts were taken for tissue culture. The 3^rd-5th generation scleral fibroblasts were chosen for the experiments. The expression levels of HGF and MMP-2 protein in the scleral fibroblasts were analyzed by Western blotting. After HGF with different doses acted on the scleral fibroblasts of the control group, MMP-2 protein expression in the scleral fibroblasts was analyzed by Western blotting. HGF siRNA was transfected into the scleral fibroblasts of the LIM group and the protein expressions of HGF and MMP-2 were analyzed by Western blotting.RESULTS:The LIM group became myopic with a significant increase in axial length (7.97±0.29 mm vs 7.01±0.26 mm, P<0.05), and a significant decrease in refraction (-5.06±0.31 D vs 0.55±0.25 D, P<0.05) compared with the control group. The protein expression of HGF in the scleral fibroblasts of the LIM group was significantly higher compared with the control group ( 1.26±0.04 vs 0.32 ±0.04, P<0.05). The protein expression of MMP-2 in the scleral fibroblasts of the LIM group was significantly higher compared with the control group (0.89±0.06 vs 0.42±0.05, P<0.05). In the scleral fibroblasts of the control group, HGF(0, 0.1, 1, 10 ng/mL) upregulated MMP-2 protein expression in a dose-dependent manner (0.35±0.03, 0.44±0.02, 0.91±0.03, 1.33±0.04, all P<0.05). In the scleral fibroblasts of the LIM group transfected with HGF siRNA, MMP-2 protein expressions were significantly decreased compared with the negative control group (0.29±0.03 vs 0.81±0.05, P<0.05).CONCLUSION:HGF is a upstream mediator of MMP-2 in scleral fibroblasts from guinea pig.