外伤性视神经损伤兔动物模型建立的实验研究

The establishment of animal model for traumatic optic neuropathy in rabbits

目的建立外伤性视神经损伤的兔动物模型,为进一步研究提供实验基础。方法手术建立兔视神经挤压伤模型。将兔分为正常对照组和损伤后1 h、2周、4周组,观察损伤后不同时间点模型动物的视神经形态学及视觉诱发电位的改变。结果①对照组视神经纵切面胶质细胞基本呈柱形均匀排列,神经纤维排列整齐,染色均匀,横切面见血管形态良好;损伤组随着时间的推移可见出血、肿胀逐渐加重的轴突变性,脱髓鞘样变,血管渗出,胶质细胞增生。②每只健康兔图形翻转视觉诱发电位(P-VEP)检查均引出典型电压和时间曲线(NPN),视神经挤压伤后1 h NPN波形低阔扁平,P波潜伏期延长,波幅降低,与对照组相比有统计学意义(P<0.05),伤后2周潜伏期进一步延长,波幅降低,伤后4周波形消失。伤后2周、4周分别与对照组、伤后1 h相比及伤后2周、4周相互比较均有统计学意义(P<0.01)。结论成功建立外伤性视神经损伤的兔动物模型,视神经损伤后形态学与功能学均有显著改变,为外伤性视神经损伤发病机制的相关研究奠定良好基础。

Objective To establish an animal model of traumatic optic neuropathy in rabbits. Methods Animal model of traumatic optic neuropathy was established by operation. The morphological changes and visual evoked potentials were observed at different time points after operation. Results （1） In the control group, glial cells presented cylinder shapes and neural fibers arranged neatly. But in the model groups, the haemorrhage and swelling of optic nerve could be seen and the degrees of sheet necrosis, demyelination, blood vessels＇ oozing and glial cell＇s hyperplasia were aggravated with the increase of time after injury. （2） Pattern reversal visual evoked potential （P- VEP） of each health rabbits showed typical NPN contours. But in the model groups, at the time points of 1 hour and 2 weeks after injury, NPN waves were low and flat, with lengthened latent period and reduced amplitudes of P waves. At the time point of 4 weeks after injury, NPN waves vanished. The differences of parameters between control group and model groups were statistically significant. Conclusion The obvious changes of morphology and the visual function show successful establishment of the animal model of rabbits＂ traumatic optic neuropathy.