论文部分内容阅读
目的研究巨噬细胞激活状态与视神经损伤后视网膜节细胞(retinal ganglion cell,RGC)存活及神经轴突再生的关系.设计实验性研究.研究对象费希尔大鼠23只.方法在费希尔大鼠上建立视神经损伤及自体外周神经嫁接模型,在玻璃体腔分别注射巨噬细胞激活剂酵母多糖(zymosan,ZYM)或联合巨噬细胞抑制因子(macrophage inhibitory factor,MIF).大鼠存活3周后灌流同定取视网膜,灌流之前3天进行荧光金标记.对取出的视网膜进行免疫荧光染色,平铺视网膜后在荧光显微镜下分别计数存活RGC、轴突再生性RGC和巨噬细胞的数量.实验分为生理盐水对照组、ZYM组、MIF组及ZYM联合MIF组.主要指标巨噬细胞、存活RGC及轴突再生性RGC的数量.结果对照组巨噬细胞、存活及轴突再生性RGC数量分别为91 ±6.1/mm2、185±9.0/mm2及35±2.9/mm2,与对照组相比,ZYM组可使眼内巨噬细胞(883±93.9/mm2)的数量增至近十倍,同时可明显促进RGC存活(299±13.1/mm2)及神经轴突再生(99±13.5/mm2);MIF组本身对RGC的存活及轴突再生情况无明显影响.当巨噬细胞被激活后,联合应用MIF虽未能减少眼内巨噬细胞的数量(828±72.9/mm2),但可有效降低这些巨噬细胞对RGC轴突再生(67±2.2/mm2)的促进作用.结论巨噬细胞被酵母多糖激活后具有促进RGC的存活及神经轴突的再生,而巨噬细胞抑制因子对巨噬细胞的抑制作用可使其促神经再生的作用明显降低.“,”Objective To investigate the relationship between macrophage activation status and neural repair after optic nerve injury.Design Experimental study.Participants 23 Fischer rats.Methods Optic nerve (ON) of Fischer rat was transected and grafted with an autologous peripheral nerve(PN) and let to survive for three weeks.Zymosan (ZYM) and macrophage inhibitor) factor (MIF) were injected intraocularly after PN-ON procedure to change the macrophage activation status.To retrograde label the regenerating retinal ganglion cells(RGCs),fluorogold(FG) was slowly injected into the distal end of the PN graft three days before the perfusion.The amount of survival and regenerating RGCs and macrophages on the flat mounted retinas were counted after the perfusion and immunofluorescence staining.The experiment was divided into normal saline control group,ZYM group,MIF group,ZYM±MIF group.Main Outcome Measures Number of macrophage,surviving RGCs and axon-regenerating RGCs.Results Number of macrophages,surviving RGC and axon regenerating RGC in the control group are 91±6.1/mm2,185±9.0/mm2 and 35±2.9/mm2 respectively.Compared to the control group,ZYM group obviously increased the number of intraocular macrophages by nearly ten folds (883±93.9/mm2),along with enhanced RGC survival (299±13.1/mm2) and axon regeneration (99±13.5/mm2).MIF group itself did not change RGC survival and axon regeneration.When macrophages were activated,however,combine application of MIF can substantially decrease the promoting effects of macrophage on axon regeneration (67±2.2/mm2),though the number of macrophages was not decreased (828±72.9/mm2).Conclusion Macrophages activated by ZYM can promote RGC survival and axon regeneration.Inhibition of macrophage activation by MIF leads to obvious down-regulation of axon regeneration of ON injury.