rAAV介导BDNF基因转染对急性高眼压兔眼神经损害的保护作用  

Neuroprotective effect of rAAV-mediated rhBDNF gene transfection on rabbit retina against acute high intraocular pressure

作　　者：王建明[1] 孙乃学[1] 惠娜[1] 范雅稚[1] 冯海晓[1] 赵世平[1] 

机构地区：[1]西安交通大学医学院第二附属医院眼科,陕西西安710004

出　　处：《南方医科大学学报》2009年第9期1770-1774,共5页Journal of Southern Medical University

基　　金：陕西省自然科学基金(2001SM66);西安交通大学医学院第二附属医院科研基金(2003-11)

摘　　要：目的通过检测视网膜电图b波(ERG-b)、计数视网膜节细胞(RGC)、测量内层视网膜(IRL)厚度、电镜观察RGC超微结构变化等,探讨玻璃体注射携带人脑源性神经营养因子(hBDNF)重组腺伴随病毒(rAAV-BDNF)对急性高眼压兔眼神经损害的保护作用。方法24只健康日本大耳白兔任选一眼作为造模眼(为模型组,共24眼),用生理盐水前房灌注法造成急性高眼压模型,对侧眼不作任何处理作为正常对照组(24眼)。另24只健康日本大耳白兔任选一眼作为造模眼(为BDNF组,共24眼),BDNF组在造模前3d玻璃体内注射10μlrAAV-BDNF。于造模后第1、3、7、14d三组各摘除6只观察眼做病理切片,进行RGC计数、IRL厚度测量。三组中第14天结束观察的各6只观察眼,在实验开始前(基线)及造模后第1、3、7、14天,分别检测ERG-b波。另选5只兔用于观察RGC的超微结构,其中1只不做任何处理;另4只兔单眼造模(模型组2只,BDNF组2只),第7天处死。结果造模前三组的ERG-b波的振幅值无显著性差异(P>0.05)。模型组和BDNF组ERG-b波振幅值在造模后第1天均降至最低水平,与基线比较差异有显著性(P<0.01);以后逐渐恢复,但第14天均未能恢复至基线水平(P<0.01)。实验结束时BDNF组ERG-b波振幅值高于模型组(P<0.01)。模型组兔眼视网膜RGC数量减少、IRL厚度变薄。BDNF组兔眼视网膜RGC数量和IRL厚度的变化与模型组相似,但其程度均较模型组轻(P<0.05,P<0.01)。电镜观察可见急性高眼压引起了RGC的损害,而BDNF组损害较轻。结论玻璃体注射rAAV-BDNF可以显著改善急性高眼压引起的ERG-b波及视网膜结构的损害,具有神经保护作用。Objective To investigate the neuroprotective effect of human brain-derived neurotrophic factor gene transfection into rabbit retina against acute high intraocular pressure （HIOP）. Methods Acute HIPO was induced in one eye of 24 white rabbits via saline perfusion into the anterior chamber （model group）, and the contralateral eye without treatment served as the control group. In another 24 rabbits, 10 μl recombinant adeno-associated virus （rAAV） vector containing human BDNF gene （rAAV-BDNF） was injected into the vitreous body of one of the eyes 3 days before the operation for HIPO （BDNF group）. At 1, 3, 7, and 14 days after HIOP model establishment, 6 eyes in each group were excised to observe the number of retinal ganglion ceils （RGCs） and the thickness of the inner retina layer. For the eyes dissected on day 14, electroretinogram b （ERG-b） wave was detected 30 min before （baseline） and on days 1, 3, 7, and 14 after HIOP. Another 5 rabbits were used for ultrastructural observation of tlae RGCs using transmission electron microscopy; including 1 without treatment, 2 with unilateral HIOP and 2 with rAAV-BDNF transfection before HIOP. Results The amplitude of ERG-b wave showed no significant difference between the 3 groups before HIOP （P〉0.05）. In HIOP model group and BDNF group, the amplitude decreased to the lowest at 1 day after HIOP and failed to recover the baseline level at 14 days （P〈0.01）; at the end of the observation, the amplitude was significantly higher in BDNF group than in the model group （P〈0.0I）. Decreased number of RGCs and thickness of inner relina layer occurred in the model group, but these changes were milder in BDNF group （P〈0.05, P〈0.01）. Electron microscopy revealed ultrastructural changes in the RGCs following acute HIOP, and transfection with rAAV-BDNF ameliorated these changes. Conclusion rAAV-BDNF transfection protects the retinal structure and improves the amplitude of ERG-b wave after acute high IOP suggesting its neuroprotectiv

关 键 词：脑源性神经营养因子 腺伴随病毒 高眼压 视网膜 

分 类 号：R775.9[医药卫生—眼科]