Functional Recovery of Vision with Axonal Regeneration in Crushed Optic Nerve

1.巨噬细胞激活视神经损伤后的轴突再生当将氧化型Galectin-1巨噬细胞激活剂注入成年猫的玻璃体中时，视网膜神经节细胞(RGCs)的损伤轴突向外延伸。再生轴突在视神经(Opn)中持续延伸至4周，2周后无新纤维进入视神经(Opn)。2.应用ROCK抑制剂Y-39983和Y-27632促进视网膜培养中轴突的延伸。比较新型ROCK抑制剂Y-39983和Y-27632对3D视网膜培养中轴突延伸的影响。Y-39983在3~20μM时促进神经突起和胶质突起的伸展，在100μM时完全抑制伸展；Y-27632在10~30μM时仅促进神经突起的伸长，在100~300μM时完全抑制神经突起和神经突起的伸展。Y-39983和Y-27632对损伤视神经的轴突再生。根据视网膜培养结果，我们采用10μM Y-39983将视网膜神经节细胞轴突再生到损伤的视神经中。当Y-39983注射到玻璃体和挤压部位时，许多轴突延伸到挤压部位之外，而注射生理盐水的OPN中没有纤维。在移植的周围神经节段，当RGCs再生轴突时，On-RGCs的数量比Off-RGCs多。注射BDNF、CNTF和Forsklin仅能增加再生轴突的数量和轴突切断后的存活率。注射抗青光眼药物尼普拉地洛可增加脱离视网膜节细胞存活的轴突和再生轴突的数量。

1.Axonal regeneration in crushed optic nerve with macrophage activationWhen oxidized galectin-1, a macrophage activator, was injected into the vitreous of adult cats, crushed axons of retinal ganglion cells (RGCs) extended beyond the crushed site. Regenerated axons continuously extended in the optic nerve (OpN) until 4 weeks, however no fibers newly entered into the OpN after 2 weeks.2.Promotion of neurite extension in retinal culture with ROCK inhibitors, Y-39983 and Y-27632We compared effects of Y-39983 (novel ROCK inhibitor) and Y-27632 on neurite extension in 3D retinal culture. Y-39983 promoted extension of both neurites and glial processes at 3-20 μM, totally inhibited the extension at 100 μM. Y-27632 promoted extension of only neurites at 10-30 μM, extension of both neurites and glial processes at 100-300 μM, totally inhibited the extension at 1 mM. Very few neurites emanated from retinal pieces in culture without the drugs.3.Axonal regeneration in crushed optic nerve with Y-39983 and Y-27632From the results in retinal culture, we adopted 10 μM Y-39983 to regenerate RGC axons into the crushed OpN. When Y-39983 was injected into the vitreous and crush site, many axons extended beyond the crush site in contrast with no fibers in saline injected OpN. The number of fibers were doubled in the OpN with second injection at day 7.4.OFF-RGCs have smaller ability to survive axotomy and regenerate axonsWhen RGCs regenerate axons into a transplanted peripheral nerve segment, number of ON-RGCs exceeds that on OFF-RGCs. An injection of BDNF, CNTF and forskolin increased only the number of OFF-RGCs regenerating axons as well as surviving axotomy. An injection of nipradilol, anti-glaucoma drug, increased number of OFF-RGCs surviving axotomy and regenerating axons.