| To investigate the survival of retinal ganglion cells(RGCS) after optic nerve cut and the regeneration of axons after the incomplete optic nerve injury in vivo treated by intravitreous injection of mixed crystallines.Methods1.Adult male Long-evans rats were divided into 3 experimental groups and a normal control group.5μcrystallines of different concentration(1×10-3g/L,1×10-4g/L,1×10-5g/L) were injected into vitreous cavity and the changes of the retina and RGCs were observed by light and electron microscope after 5 days.2.To evaluate the effect of survival of RGC in vivo by means of intravitreous injection of the mixed crystallines.Flurogold retrograde tracing was used to stain RGCs and actived microglia.3.WGA anterograde tracing and electron microscopy were also applied to evaluate axonal regeneration of RGCs.4.F-VEP was performed before the injury and every time point after injury.Results1,The retinal changes of light microscope were within normal limit.Mild damage in some mitochondrial crista of RGCs was observed only in the group with crystallines 1×10-3g/L intravitreous injection.2,Intravitreous injection of mixed crystallines can rescue some RGCs,and the survival rate of RGCs significantly increased from 51.5%,17.9%and 12.2%at 1w,2w and 3w post-injury to 70.6%,32.2%and 15.2%respectively,compared to the control eyes(p＜0.01).3,Treatment of intravitreous injection of mixed crystallines can reduce the glial response to injury,decrease and retard activation of microglia,with the consequence of lowering non-selective phagocytosis of degenerating but still surviving RGCs.4,Treatment of intravitreous injection of mixed crystallines can sprout and improve more axons to regenerate unhindered,and the amplitude of F-VEP showed obvious recovering on 4-8weeks after the injury.Conclusions1.There is no toxicity of crystallines(1×10-4g/L and 1×10-4g/L) by intravitreous injection).2.Intravitreous injection of mixed crystalline can rescue some RGCs and reduce activation of microglia.3.Intravitreous injection of mixed crystalline can clear the path for axons to sprout and improve the regeneration of the axons as well as partly restore the visual function.
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