VEGF抑制剂（贝伐单抗）治疗早产鼠视网膜病变的实验研究

The experimental study of VEGF inhibitor （bevacizumab） on the treatment of retinopathy of premature rats

目的 通过建立早产高氧鼠视网膜病变SD大鼠模型,观察新生血管病理变化及其VEGF的表达情况,同时比较贝伐单抗球周注射和玻璃体腔注射对早产鼠视网膜病变的影响.方法 随机数字表法将90只早产幼鼠建立视网膜病变模型后分为3组,高氧组、球周注射组、玻璃体腔组,每组各30只;将健康幼鼠36只纳入实验,作为正常对照组.每组随机取10只幼鼠右眼制作视网膜铺片,观察右眼视网膜血管形态;取10只摘除右眼球,石蜡包埋,行HE染色,观察右眼球视网膜新生血管数目;取10只右眼球提取RNA,用RT-PCR检测VEGF的表达情况.结果 视网膜铺片显示正常组可见血管自视盘发出向四周呈反射性分布,分支良好,走形规则,结构清晰.高氧组、球周注射组、玻璃体腔组发生新生血管.高氧组视网膜血管内皮细胞核数较正常组明显增多（P＜0.05）,部分可见串状红细胞;球周注射组和玻璃体腔组均比高氧组减少（P＜0.05）,且两组之间差异无统计学意义（P＞0.05）.VEGF的mRNA表达趋势与HE染色趋势一致.结论 贝伐单抗能够抑制VEGF在早产高氧鼠视网膜病变中的表达增高,贝伐单抗球周注射和玻璃体腔注射疗效相近,但前者比后者更安全。

Objective To establish hyperoxia retinopathy in premature rat model with SpragueDawley （SD）,observe the pathological changes of angiogenesis and expression of vascular endothelial growth factor （VEGF）,and compare the effect of bevacizumab periocular injection and intravitreal injection of retinopathy of premature rats.Methods Ninety preterm rat retinopathy models were randomly divided into 3 groups：high oxygen group,retrobalbar injection group,and vitreous cavity group （n =30 per group）;36 healthy rats were chosen as the normal control group.Each group were randomly selected 10 rats＇right eyes to make retinal flat mount to observe the right eye retina vascular morphology;10 resections of right eyes were embedded in paraffin,and stained with hematoxylin eosin （HE）;the number of right eye of retinal neovascularization was observed;the right eye RNA was extracted,and reverse-transcription polymerase chain reaction （RT-PCR） was used to detect the expression of VEGF.Results The normal group showed retinal vessels were around a reflection of distribution,good branch,shape rules,and clear structure.Intravitreous neovascularization occurred in the high oxygen group and peribulbar injection group.Retinal vascular endothelial cells in the high oxygen group were increased significantly compared to the normal group （P 〈 0.05）.The visible clusters of red blood cells in the periocular injection group and vitreous group were decreased compared to the high oxygen group （P 〈 0.05）,but no significant difference between the periocular injection group and vitreous group （P 〉 0.05）.The expressions of VEGF mRNA and HE staining had a consistent trend.Conclusions Bevacizumab inhibited the expression of VEGF that was increased in premature rats in hyperoxia retinopathy.The effects of bevacizumab periocular injection and intravitreal injection were similar,but the former was more secure than the latter.