大剂量地塞米松对视神经损伤后再生影响的研究

The Survey on the Regeneration Effection After the Injury of the Optic Nerve with High-dose Dexamethasone

目的:观察大剂量地塞米松应用对家兔视神经夹挫伤后视网膜神经节细胞(Retinal ganglion cells,RGC)存活及损伤视神经再生的影响及损伤视神经、视网膜HSP-27表达的变化.方法:采用兔球后视神经钳夹伤模型,5月龄健康成年家兔分为正常对照组(CON)、损伤组(ING)、大剂量地塞米松组(LDM).分别于损伤后3 d、7d1、4 d处死动物.观察视神经损伤后单位面积RGC存活数量及损伤后热休克蛋白27(Heat shock protein 27HSP-27)在视神经、视网膜的表达变化.结果:视神经损伤后,LDM组RGC的存活数高于损伤组(P<0.01).损伤组损伤后3 d7、d、14 d视神经、视网膜HSP-27可见表达.LDM组损伤后可见视神经、视网膜HSP-27的表达增强,各时间点均高于损伤组,差异有显著统计学意义(P<0.01).结论:视神经损伤后,大剂量地塞米松能够增加RGC的存活数量,能上调HSP-27的表达,这可能是应用大剂量地塞米松后促进损伤视神经再生的作用机制之一.

Obstract To observ the changes about the application of high--dose dexamethasone on rabbit optic nerve contusion folder RGC survival and regeneration of optic nerve damage and the damage of the potic nerve,retion expression of HSP-27. Methods Using the rabbit clamp retrobulbar optic nerve injury model, 5- month- old healthy adult rabbits were divided into normal control group, injury group, high- dose dexamethasone. And the animals were killed after injurying 3 d,7 d, 14 d respeetiviely. Observing the expression changes about the number of RGC survival in the unit area after injurying and the Heat shock proteion HSP-27 in the retional and the optic nerve. After injuring the optic nerve,the results is that the survival of LDM GROUP is higher than the RGC GROUP. After injuring 3 d,7 d,14 d,optic nerve,retional expression of Hsp-27 can be seen. The optic nerve, retional HSP-27＇s expression increased after enjuring I.DM GUOUP and were higher than the injury group at different time points,and there was a significant difference statistically significant（p〈0. 01）. Conclusion After injurying the optic nerve, high-dose dexamethasone can increase the number of RGC survival,and increase HSP-27＇s expression. This may be one of the mechanisms that using high-dose dexamethasone promote regeneration of optic nerve injury.