氧诱导的血管增生性视网膜病变小鼠模型

A model of vascular proliferation in oxygen-induced retinopathy in mouse

目的 建立可量化的血管增生性视网膜病变小鼠模型。方法 将鼠龄为7d的C57BL/6J幼鼠17只暴露于75％氧浓度环境下饲养持续5d,然后回到正常空气中饲养;17只同龄幼鼠置于正常空气环境中饲养作为对照。ADP酶法视网膜铺片了解视网膜血管的改变;用组织切片观察并计数突破视网膜内界膜的内皮细胞核数目;视网膜组织切片用CD31进行免疫组织化学染色。结果 持续高浓度氧使幼鼠视网膜血管收缩、分支闭塞、中央部可见灌注降低,相对低氧使视网膜血管扩张、增生。组织切片可见正常对照组平均每张切片突破内界膜内皮细胞核数目<1个,给氧组平均24个/切片,两组比较差别有显著性意义(P<0.01)。给氧组视网膜组织切片经用CD31抗体处理后显示内界膜玻璃体面细胞染色阳性。结论 该模型具有可重复性强、可定量研究的优点,是进行视网膜新生血管发生机制及药物干预的合适模型。

Objective To establish a quantifying model of retinopathy with vascular proliferation in mouse. Methods Seventeen one-week-old C57BL/6J mice were exposed to 75% oxygen for 5 days and then to room air. Age matched seventeen mice without high oxygen exposure were used as controls. The ADPase histochemical technique was applicated for retinal flat mount to assess the oxygen-induced changes of retinal blood vessels. The proliferative neovascular response was quantified by counting the endothelial cell nuclei of new vessels extending from retina into the vitreous in 6um sagittal cross-sections. Immunocytochemistry was performed on some of cross-sections of the retina by using an endothelial cell-specific antibody CD31. Results Constriction and occlusion of the retinal blood vessels and decrease in central perfusion were found under the hyperoxia condition, and dilation and proliferation of blood vessels were found under the relatively hypoxia status. The mean neovascular nucleus per cross-section was 24 in hyperoxia group, while less than 1 nucleus per cross-section in the normoxia control ( P < 0. 001). Immunocytochemistry staining showed CD31 positive cells localized in the vitreal side of the inner limiting membrane in the retinal sections of oxygen-treated eyes. Conclusion The reproducible and quantifiable mouse model of oxygen-induced retinal neovascularization may prove to be useful for the study of pathogenesis of retinal neovascularization and medical intervention.