大鼠视神经横断伤及夹挫伤后视网膜神经节细胞变化及与损伤时间关系

The comparison of the RGCs changes of retina and the relationship with injury time after optic nerve transection/crush of rat

目的观察大鼠视神经横断伤及夹挫伤后，视网膜神经节细胞（RGCs）形态学变化、区别及在不同时间的计数变化，探讨其与视神经损伤经过时间的关系，为视神经损伤的病理机制及损伤经过时间的推断提供一定的依据。方法采用大鼠球后视神经横断伤／夹挫伤动物模型，在伤后不同时间处死动物并取材，HE染色，光镜下观察RGCs的动态变化。结果视神经损伤后RGCs数目均严重下降，2周内RGCs快速减少，3～7d为RGCs快速减少期，2周以后缓慢减少；但横断伤组3d以后各个时期RGCs计数下降幅度与夹挫伤组相比更明显。结论视神经损伤导致了视网膜形态结构的变化，RGCs丢失的严重程度与损伤类型及时间呈相关性。

Objective To observe morphological features of retina and the alteration of counted number of retinal ganglion cells （RGCs） in rat retina at various intervals after optic nerve transection/crush, and study the relationship between the alteration and post-injury interval. Methods In this experiment, intraorbital optic nerve transection/crush model of rats was used. Paraffin section was cut after the test group rats were killed after various survival interval and the hemotoxylin and eosin（HE） staining was carried out meanwhile. The changes of retina was observed using light microscope. Results RGCs were reduced significantly due to optic nerve injury. An initial loss was accelerated by 2 week after optic nerve injury, RGCs lossed fastly and abruptly during 3 to 7 days after optic nerve injury, the later declines was protracted in RGCs densities. But three days later, in the optic nerve transection group, the counted number of RGCs lossed more obviously than the optic nerve crush group at various intervals. Conclusions Changes of morphology were observed in retina after optic nerve injury. There is a rule that the degree of the RGCs loss had a relationship with injury type and injury time, which will be of value in time estimation of optic nerve injury.