高血脂对脉络膜VEGF表达的影响

Research on the expression of VEGF on choroidal blood vessels of hyperlipidemia rabbits

目的:研究高血脂动物模型脉络膜组织学改变及VEGF的表达,初步探讨高血脂在年龄相关性黄斑变性(AMD)患者脉络膜新生血管(CNV)形成中的作用及其机制。方法:新西兰大白兔36只随机分为正常对照组与实验组,分别喂养普通饲料与高脂饲料。分别于1,2,3mo后应用免疫组织化学法和RT-PCR法对脉络膜VEGF表达进行检测。结果:免疫组织化学结果显示对照组视网膜和脉络膜各层VEGF弱表达;实验组1mo时脉络膜组织中VEGF表达与对照组差异无统计学意义(t=0.442,P=0.668);2mo时脉络膜组织中VEGF表达较对照组明显增强(t=2.330,P=0.042);3mo组脉络膜组织中VEGF表达较对照组明显增强(t=3.542,P=0.005)。RT-PCR示对照组脉络膜组织中可以检测到微弱的VEGFmRNA表达;实验组1mo时脉络膜组织中VEGFmRNA的表达与对照组差异无统计学意义(t=1.703,P=0.119);2mo组脉络膜组织中VEGFmRNA表达较对照组明显增强(t=14.138,P<0.001);3mo组脉络膜组织中VEGFmRNA表达较对照组明显增强(t=15.240,P<0.01)。结论:高血脂通过直接损害脉络膜血管和增强VEGF的表达可能诱导CNV的发生。

AIM： To investigate the expression of vascular endothelium growth factor（VEGF） in the choroidal blood vessels of hyperlipidemia rabbits, to explore the role of hyperlipidemia in the pathogenesis of choroidal neovascularization（CNV） in age-related macular degeneration（AMD）. METHODS： Thirty-six rabbits were randomly divided into 2 groups, normal control group and hyperlipidemia group by feeding respectively standard diet and high cholesterol diet.The expression of VEGF was analysed with immunohistochemical method and RT-PCR at 1month, 2, 3 months. RESULTS：Immunohistochemical method showed that the expression of VEGF was weak in normal control group.The expression of VEGF was enhanced in hyperlipidemia group and the difference was statistically significant when group G2,G3 compared with group C2（P0.05）,C3（P0.01）, and nonsignificant when group G1 compared with C1 （P0.05）. RT-PCR showed that VEGFmRNA was detected in both normal control group and hyperlipidemia group. The expression of VEGFmRNA paralleled to the result of immunohistochemical method. CONCLUSION：The lesion on the choroidal blood vessels and enhanced expression of VEGF caused by hyperlipidemia might lead to CNV.