霍乱毒素对远端视神经损伤后视网膜节细胞再生的影响

THE EFFECTS OF COLERA TOXIN ON THE REGENERATION OF THE RETINAL GANGLION CELLS AFTER DISTAL AXOTOMY OF THE OPTIC NERVE

目的 探讨霍乱毒素 (CTx)对成年金黄地鼠远端视神经受损后视网膜节细胞 (RGCs)再生的作用。方法 远端切断视神经并对接一段自体坐骨神经 (AG) ,玻璃体内注射CTx及 或植入小段坐骨神经分支 (SN)。动物随机分为对照组Ⅰ (AG组 )与对照组Ⅱ (溶剂组 ) ;AG +SN组 ;AG +CTx组 ;AG +SN +CTx组和量效关系组 ,前五组分别存活 4周～ 6周 ,用粒蓝逆行标记再生的RGCs ,荧光显微镜下观察。 结果 AG +CTx组各时间点再生的视网膜节细胞比对照组Ⅰ与对照组Ⅱ明显增加 ,具统计学意义 (P <0 0 5 ) ;AG +SN组得出相似结果。AG +SN +CTx组与其它几组相比在各时间点上均存在极显著性差异 (P <0 0 1)。 结论 霍乱毒素可明显提高远端视神经受损后视网膜节细胞的再生。

Objective To investigate the effects of Colera Toxin(CTx) on the regeneration of retinal ganglion cells (RGCs) after distal axotomy in adult hamsters. Method After transecting the optic nerve(ON) intracranically,an autologus sciatic nerve (attached graft,AG) was removed and connected to the proximal stump of the ON.CTx was injected and/or a 2mm segment of sciatic nerve(SN) was inserted intravitreally.Animals were divideded into six groups:control group 1(AG group) and control group 2(solution group);AG+SN group;AG+CTx group;AG+SN+CTx group;effect and dosage group.Animals in the former five groups were allowed to survive for 4-6 weeks respectively.Granular blue fluorescent retrograde labeling method was used to measure the quantity of regenerating RGCs of control and experiment animals. Results The mean number of regenerating RGCs in AG+CTx groups were increased and significantly higher than those in control group 1 and control group 2 at each time point(P<0 05).Similar results were obtained in AG+SN groups;The mean number of regenerating RGCs in AG+SN+CTx groups were significantly higher than those of other groups at each time point(P<0 01).Conclusions Our results indicated that CTx had significant effects on promoting the regeneration of RGCs after distal axotomy.;