ABSTRACT
Objective To establish the high myopic choroidal neovascularization (CNV) in guinea pigs and to investigate the role of (matrix metalloproteinase-2,MMP-2) and tissue inhibitor-2 of metalloproteinase (TIMP-2) in high myopic CNV.Methods Seventy-two 2-week-old guinea pigs were randomized into control group (n =36) and high myopia group (n =36).Right eyes were indued form deprivation high myopia for 6 weeks.Thirty guinea pigs were randomly selected in each group,and CNV were induced in the right eyes br the 532 nm laser.MMP-2 and TIMP-2 expressions were investigated by immunohistochemistry pre-laser and 7,14,21,28,35 days after laser induction,respectively,while MMP-2 and TIMP-2 relative expression levels in retinal pigment epithelium (RPE)-choroid-sclera complex were detected by real-time PCR.Integral opitical density (IODs) of positive expression and mRNA relative expression levels of these factors were performed by statistical analyses.Results The expressions of MMP-2 and TIMP-2 were up-regulated in the two groups after laser photocoagulation through immunohistochemistry and real-time PCR examinations.Expression of MMP-2 peaked at 21 d and TIMP-2 at 28 d,respectively.IODs of positive expression and mRNA relative expression levels of MMP-2 were higher in high myopia group than those in control group at each inspective time point,and the differences were statistically significant (P ＜ 0.05).TIMP-2 expression was significantly reduced in high myopia group compared with control group before laser photocoagulation (P＜0,05),while there was no significant difference between the two groups at each time point after laser photocoagulation.Conclusions MMP-2 and TIMP-2 were closely related to the formation of high-myopic CNV.Balance disorders of MMP-2 and TIMP-2 might participate in the occurrence and development of high-myopic CNV.