阻断促红细胞生成素抑制小鼠视网膜新生血管生成

Blockade of retinal neovascularization by inhibiting erythropoietin in a mouse model

目的：建立C57BL/6小鼠氧致血管增生性视网膜病变模型（oxygen induced retinopathy,OIR）,探讨阻断促红细胞生成素（Erythropoietin,EPO）对视网膜新生血管的抑制作用。方法：取鼠龄7d（P7）的健康C57BL/6小鼠置于75%±2%氧气浓度的密闭氧舱中5d,鼠龄12d（P12）时返回正常空气环境以建立氧诱导鼠视网膜新生血管模型;新生小鼠于P12~P16隔日给予玻璃体腔内注射0.5μL含有25ng（A组）,50ng（B组）,250ng（C组）可溶性EPO受体的PBS液以及不含EPO受体的PBS液（D组）。于P17时分批处死各组小鼠,小鼠眼球以4%多聚甲醛固定,制成病理切片,进行视网膜组织形态病理学观察计数突破内界膜新生血管细胞核数,了解视网膜新生血管增生程度。结果：计数病理切片突破内界膜新生血管细胞核数目,各组玻璃体内EPO受体注射组较PBS注射组新生血管细胞核数明显减少,差异有统计学意义（P〈0.01）。并且各不同浓度EPO受体组间新生血管细胞核计数差异亦有统计学意义（P〈0.01）,随着EPO受体浓度增高,突破内界膜新生血管内皮细胞数减少。结论：可溶性EPO受体玻璃体腔内注射能够阻断EPO的促新生血管生成作用,有望成为治疗眼部新生血管性疾病的新方法。

AIM： To establish the murine model of oxygen induced retinopathy（ OIR） and to evaluate the inhibition of retinal neovascularization by erythropoietin（ EPO） blockade.METHODS： Neonates of C57BL/6 mouse（ P7） were exposed to 75% ±2% oxygen for 5d and return to normal air environment when 12d（ P12） to establish oxygen-induced retinal neovascularization model. The neonates were divided into groups,injected with 0. 5μ L solution containing 25ng（ group A）,50ng（ group B）,250ng（ group C） of soluble erythropoietin receptor（ EPO- R） or PBS（ group D） at P12,P14 and P16 in the right eye. On P17,the litters were sacrificed and their right eyes were enucleated and fixed with 4% paraformaldehyde,made pathological section. The number of breakthrough internal limiting membrane neovascular nuclei was counted with pathological retinal morphology,understanding theproliferative degree of retinal neovascularization.RESULTS： The pathological sections showed the neovascular cell nuclei which penetrating the inner limiting membrane in intravitreal EPO receptor injection group was reduced statistically than that in PBS injection group,the difference was statistically significant（ P 〈0. 01）. And,neovascular nuclei count differences in the various concentrations of EPO receptor group was statistically significant（ P 〈 0. 01）. With the EPO receptor concentration increase, neovascular endothelial cells broken through the internal limiting membrane was reduced.CONCLUSION： Intravitreal injection of soluble EPO receptor can block EPO and improve neovascularization.The new method is expected to become new treatment of ocular neovascular diseases.