标准化大鼠外伤性视神经损伤动物模型建立  

Creation of standard animal model of optic nerve injury in rats

作　　者：张琳琳[1] 吕瀛娟[1] 于荣国[1] 王兴[1] 申战省[1] 张蔚[1] 颜华[1] 

机构地区：[1]天津医科大学总医院眼科,天津300052

出　　处：《眼外伤职业眼病杂志》2008年第12期913-917,共5页Journal of Injuries and Occupational Diseases of the Eye with Ophthalmic Surgeries

摘　　要：目的建立标准化外伤性视神经损伤动物模型。方法应用液压冲击颅脑损伤仪(FPI)分别以(6.9±0.6)atm和(2.4±0.2)atm的冲击力打击Wister大鼠右、左眼眶内贴近眼球部的视神经,建立两组程度不同的视神经损伤模型。通过闪光视觉诱发电位(F-VEP)、眼眶磁共振成像(MRI)、视网膜病理、视神经电镜等方法对正常及损伤后1、3d,1、2、4、6、8周大鼠的双眼进行检测。结果(1)损伤后大鼠F-VEP与伤前相比,潜伏期延长、振幅降低,此变化具有统计学意义(P<0.05)。损伤程度越重,伤后主波潜伏期延迟及振幅降低越明显,波形变化趋于稳定所需时间也越长。(2)伤后1 d眼眶MRI显示视神经受损部位信号增高、眶内结构紊乱;伤后8周视神经受损部位的高信号仍较明显、损伤部位靠近眼球侧视神经信号不均匀。轻、重两组差别不明显。(3)光镜下伤后1 d视网膜神经节细胞层(GCL)出血,伤后4周视网膜各层细胞稀疏、排列欠整齐,GCL散在核染色质浓集、边聚的节细胞,伤后8周视网膜各层细胞明显减少,GCL内大量空化节细胞。(4)电镜下损伤后4周视神经轴索萎缩变性,髓鞘肿胀、板层松解分离,伤后8周在血管和星形胶质细胞突起的附近有新生轴突,呈簇分布、生长良好。重伤组新生轴突枝芽少于轻伤组。结论应用FPI可以成功建立标准化大鼠外伤性视神经损伤动物模型。Objective To create a standard animal model of optic nerve injury in rats. Method The right and left optic nerves of Wister rats were beaten with the pressure of 6.9 ± 0. 6atm and 2. 4 ± 0.2atm respectively using fluid percussion brain injury device （FPI）. Flash - visual evoked potential（ F - VEP） , orbital magnetic resonance imaging （ MRI ）, histopathological examines of rctiqae and optic nerves were taken before and 1, 3days, 1, 2, 4, 6, 8 weeks after injury for evaluation. Results （ 1 ） F - VEP showed the latency prolonged and the amplitude decreased after injury compared to the values before injury, the changes were significant （P 〈 0.05）. The changes were more significant in severe injury eyes than that in mild injury eyes （P 〈0.05）. （2） Orbital MRI showed that abnormal high signal could be seen on optic nerve after injury, 8 weeks after injury the injured segment of optic nerve still showed high signal and the signal of optic nerve on the globe side of the injury part was uneven. The difference between severe and mild injury groups was not obvious. （3） 1 day after injury ruptured capillary could be seen in ganglion cell layer （GCL）, 4 weeks after injury cells in each layer arranged sparsely and disorderedly, in some RGCs chromatin became dense, 8 weeks after injury the cells in each layer became fewer and large amount of RGCs without nucleus could be seen. （4） 4 weeks after injury the axons of the optic nerve atrophied and degenerated, and the myelin sheath swelled; 8 weeks after injury, new axons which displayed in clusters and well -developed could be seen adjacent to the protuberances of astrocyte and the vessels. The new axons could be easily seen in mild injury group. Conclusions A standard animal model of optic nerve injury in rats can be successfully created using FPI.

关 键 词：视神经 损伤 模型 

分 类 号：R779.1[医药卫生—眼科] R-332[医药卫生—临床医学]