视网膜挫伤兔模型的病理学观察

Pathology observation of retinal contusion rabbit model

目的:建立视网膜挫伤的动物模型,观察视网膜损伤后的形态特点。方法:选取40只健康成年无眼疾青紫蓝兔,随机分为挫伤后1,3h;1,3,7,14,30d及正常对照共8组,每组5只,选取右眼为致伤眼,以改良Allen重击法制备兔单眼挫伤性视网膜病变模型,挫伤后获取兔眼标本,以光镜及电镜观察视网膜神经感觉层的病理变化,目镜测微尺(0.01mm)对视网膜神经纤维层(nerve fiber layer,NFL)厚度、内核层(inner nucler layer,INL)厚度进行测量,并对视网膜神经节细胞(ganglion cell,GC)计数。结果:挫伤后1,3h组和1d组NFL明显增厚(P<0.05),而7d组和14d组NFL明显变薄(P<0.05),3d组和30d组NFL厚度与正常对照组比较无显著性差异(P>0.05);各挫伤组GC计数明显少于正常对照组(P<0.05)。电镜显示挫伤后3h组;1,3d组视网膜神经感觉层均出现较多的,具有凋亡形态学与生化改变特征的凋亡细胞,其中在3d组视网膜神经感觉层凋亡细胞数量达到高峰,7d组显著下降。结论:视网膜水肿和神经感觉层细胞凋亡是挫伤性视网膜病变的一个重要机制。

AIM： To set up the animal model of retinal contusion and to observe the retinal morphous characteristic. METHODS： Forty healthy rabbits without oculopathy were divided into 8 groups： 1 hour, 3 hours; 1 day, 3, 7, 14, 30 days after contusion and normal control, 5 rabbits in each group. Right eye of each rabbit was treated with Allen＇s reformative hitting method as contusive retinopathy model. The eyeballs were enucleated at different times after contusive injury in rabbit retina. The pathological change of the retina was observed by light and electron microscope. The thickness changes of nerve fiber layer （NFL）, inner nuclear layer （INL） were measured by ocaular micrometer. We counted the number of ganglion cell （GC） under light microscope. RESULTS： After contusion injury, the thickness of nerve fiber layer （NFL） obviously increased in 1 hour group, 3 hours group and 1 day group （P〈0.05）, but in 7 days group and 14 days group, the thickness of NFL obviously decreased （ P〈 0. 05）. The NFL thickness of 3 days group, 30 days group and normal control group were similar （ P〉 0. 05 ）. After contusion injury, the thickness of INL obviously increased in 1 hour group, 3 hours group and 1 day group （P 〈 0.05）, but in 7 days group and 14 days group the thickness of INL obviously decreased （P 〈 0.05）. The INL thickness of 3 days group, 30 days group and normal control group were similar （P 〉 0.05）. GC counted in every injury group was fewer than that in normal control group. Electron microscope revealed evidence of apoptotic cells after retinal contusion. They were detected in 3 hours group, 1 day group, peaked on 3 days group, and dropped precipitously in 7 days group. CONCLUSION： Retinal oedema and apoptosis is an important mechanism of sensory layer cell degeneration after retina contusion.