MMP-2和VEGF在视网膜新生血管中的表达及意义

目的探讨基质金属蛋白酶-2（MMP-2）和血管内皮生长因子（VEGF）在视网膜新生血管中的表达及意义。方法取C57BL/6J小鼠60只,随机分为高氧组和正常组,各30只。以高浓度氧诱导小鼠建立视网膜新生血管模型。采用ADP酶视网膜铺片、苏木精-伊红染色及免疫组织化学法分别观察视网膜血管的改变、计数视网膜新生血管内皮细胞数并检测MMP-2、VEGF蛋白的表达。结果高氧组视网膜可见大量新生血管形成;突破视网膜内界膜的新生血管内皮细胞核数为（33.51±2.55）个,与对照组相比差异有统计学意义（t=9.345,P〈0.05）。高氧组与对照组比较,MMP-2、VEGF蛋白在神经节细胞层、内丛状层、内核层和突破视网膜内界膜的新生血管中高表达,且二者表达呈正相关（r=0.825,P〈0.05）。结论MMP-2、VEGF共同促进视网膜新生血管的形成,且二者可能具有协同作用。

Expression and significance of MMP-2 and VEGF in retinal neovascularization

Objective Researches showed that matrix metalloproteinase-2 (MMP-2) has a critical role in the neovascularization of tumor,and vascular endothelial growth factor(VEGF)is a promoting factor of new blood vessel formation.There still is little literature about the effect of MMP-2 in retinal neovascularization up to now.This study tried to explore the expression and significance of MMP-2 and VEGF in retinal neovascularization.MethodsA retinal neovascularization model was established in 30 7-day-old cleaning C57BL/6J mice exposed to an environment of high concentration of oxygen for 5 days,and 30 matched mice were raised in normal air environment.Fifteen mice from hyperoxic group and control group were sacrificed in 10 days after treatment and the eyeballs were enucleated to make retinal stretched preparation.Adenosine diphosphate-ase (ADPase) stained retina flat-mounts was performed to assess the retinal vascular profiles,and H&E staining was applied to count the number of new vascular cell nuclei.The expression of MMP-2 and VEGF was detected using immunohistochemistry by calculating the intergrated value of positive cells.ResultsThe retinal stretched preparation presented more neovascularization in mice from the hyperoxic group compared with control group.The number of nuclei from the vascular endothelial cells in the new vessels breaking through the internal limiting membrane in the hyperoxic group was 33.51±2.55,indicating a significant increase in comparison with control group (7.27±0.20)(t=9.345,P＜0.05).There were stronger expression of MMP-2 protein and the VEGF protein in the ganglion cell layer,inner plexiform layer and inner nuclear layer,and neovascularization breaking through the internal limiting membrane in the hyperoxic group compared with control group (t=4.25,P＜0.05;t=6.38,P＜0.05).Expression of MMP-2 showed the positive correlation with the expression of VEGF(r=0.825,P＜0.05).ConclusionBoth MMP-2 and VEGF promote retinal neovascularization.The overexpression of MMP-2 and VEGF play a synergistic role during the formation of neovascularization.