摘要
背景早产儿视网膜病变等新生血管性疾病常导致不可逆性视力丧失，其氧化损伤机制研究日益受到关注，特别是脑源性神经营养因子（BDNF）对视网膜神经节细胞（RGCs）是否具有保护作用鲜有研究报道。
目的探讨BDNF在氧诱导视网膜病变（OIR）模型小鼠视网膜中的表达变化。
方法将30只SPF级C57BL/6J幼鼠完全随机分为OIR组和正常对照组，每组15只，OIR组将日龄为7 d（P7）的幼鼠与哺乳母鼠同时置于体积分数为（75±3）%氧气的环境下喂养5 d，然后返回正常环境中饲养，以建立OIR模型。分别取2个组P17幼鼠各3只处死后分离眼球，制备视网膜切片行苏木精－伊红染色，观察突破内界膜的血管内皮细胞核数目；另各组选取3只幼鼠行异硫氰酸荧光素（FITC-dextran）眶后注射制备视网膜铺片，观察视网膜血管分布。分别于2个组取P13、P15、P17小鼠各3只处死后提取视网膜组织，Western blot法检测2个组幼鼠视网膜组织中BDNF的相对表达量的变化。
结果组织病理学研究显示，正常对照组P17小鼠视网膜内界膜光滑，未见突破内界膜血管内皮细胞核，而OIR同龄小鼠可见大量突破内界膜的血管内皮细胞核和新生血管管腔。正常对照组和OIR组P17小鼠视网膜突破内界膜血管内皮细胞核数分别为（1.70±0.68）个和（45.3±3.13）个，差异有统计学意义（t＝86.5，P＝0.00）。视网膜铺片显示，正常对照组P17幼鼠视网膜血管走行正常，毛细血管呈网状分布；而OIR组P17小鼠视网膜血管迂曲，毛细血管网状结构消失，可见大量视网膜无灌注区。OIR组P15、P17幼鼠视网膜组织中BDNF相对表达量为263.992±9.451和218.432±9.710，分别高于正常对照组的230.324±7.779和115.846±7.305，差异均有统计学意义（t＝14.2、42.3，P〈0.05）。
结论BDNF在小鼠视网膜中的表达变化趋势与OIR模型鼠新生血管形成的变化趋势一致，BDNF表达变化可能与OIR的病理过程有关。
BackgroundNeovascular diseases such as retinopathy of prematurity often leads to irreversible vision loss.The study on oxidative damage mechanism is becoming more and more important.Whether brain derived neurotrophic factor （BNDF） has protection to retinal ganglion cells（RGCs） has few research reports.
ObjectiveThe study was to investigate the expression changes of BDNFin mouse retinas of oxygen-induced retinopathy （OIR）.
MethodsThirty SPF C57BL/6J immature rats were divided into OIR group and normal control group and to fifteen rats for each group.OIR models were established by raising 7-day-old （P7） mice together with maternal mouse in （75±3）% oxygen environment for 5 days and then returned to the normal air environment, and the mice of the normal control group were raised in the normal air environment.The P17 mice were sacrificed for retinal histopathological examination by hematoxylin and eosin staining, and the number of vascular endothelial cell nucleus extending the inner limiting membrane was counted.Whole retinal mounts were prepared after fluorescein isothiacyanate-dextran （FITC-dextran） （9 ml/kg） was retrosorbitally injected, and the distribution of retinal vessels was observed in P17 mice.The relative expression levels of BNDF in retinas were detected in P13, P15, P17 mice, and the results were compared between the normal control group and the OIR group.
ResultsHistopathological examination showed that retinal inner limiting membrane was smooth in the normal control group, but a lots of vascular endothelial cell nucleus extending the inner limiting membrane were seen under the optical microscope in the OIR group.The number of the vascular endothelial cell nucleus extending the inner limiting membrane was 1.70±0.68 in the normal group and 45.3±3.13 in the OIR group, showing significant difference between them （t=86.5, P=0.00）. Whole retinal mount revealed that normal retinal vessels and network-like capillaries were exhibited in the mice in the normal group, while tortuous vessels, capillary loss and non-perfusion areas were revealed in the OIR group on the whole retina mounts.The relative expressing levels of BDNF in retinas were 263.992±9.451 and 218.432±9.710 in P15 and P17 mice in the OIR group, which were significantly higher than 230.324±7.779 and 115.846±7.305 in the normal control group （t=14.2, 42.3, P〈0.05）.
ConclusionsOIR can be inhibited by increasing the expression of BNDF.
出处
《中华实验眼科杂志》
CAS
CSCD
北大核心
2016年第1期56-59,共4页
Chinese Journal Of Experimental Ophthalmology
基金
基金项目：内蒙古自治区医疗卫生科研计划项目（201303046）
内蒙古自然科学基金项目（2014BS0804）
