目的:观察嗅鞘细胞在成年大鼠视神经眶内断端移植的冻融周围神经中存活、生长与分布随存活时间的变化及对视神经再生的影响。 方法:取成年大鼠坐骨神经反复冻融后,自两端注入10μL嗅鞘细胞悬液(105/μL),再移植于同种异体动物经眶内切断的视神经眶内断端上,分别于术后2d;1,2,3及4wk取移植物,切片观察嗅鞘细胞在其中的存活、生长及分布,并计数术后3,4wk动物视网膜内经移植物远端以50g/L荧光金逆行标记的再生视网膜节细胞。 结果:嗅鞘细胞自注射部位增殖并迁移至周围神经全段,2wk时数量达到高峰,3,4wk时仅见神经周边部位残存极少量嗅鞘细胞,且视网膜内未见任何轴突再生的视网膜节细胞。 结论:嗅鞘细胞可在冻融周围神经移植物中存活2-3wk,神经周边部位较实质内更有利于嗅鞘细胞生长,这种移植物不能发挥促进视神经再生的作用。
AIM: To study the survival, growth and distribution of olfactory ensheathing cells (OECs) in the freeze-thawed peripheral nerve (PN) graft transplanted onto the ocular stump of the transected optic nerve (ON) and the effect of this OEC-containing graft on the axonal regeneration of retinal ganglion cells (RGCs) in adult rats. METHODS: The freeze-thawed sciatic nerves with injected cultured OECs were implanted onto the ocular stumps of the transected ONs in homogeneous animals, The labeled OECs in the PN grafts were observed 2d, 1, 2, 3 and 4wk after transplantation. The numbers of retrogradely-labeled regenerating RGCs were also counted 3 and 4wk following transplantation. RESULTS: OECs proliferated and migrated from the injection sites to the whole PN with hiqhest numbers at 2 wk time point. Only a few survived OECs could be detected in the periphery of the gratft 3 and 4wk after transplantation. No regenerating RGCs could be detected in the retinas of all animals. CONCLUSION: The OECs can survive for 2-3wk in the freeze-thawed PN grafts with the peripheral areas being more beneficial for the survival and growth of OECs. Such freeze-thawed PN grafts can not promote the axonal regeneration of RGCs.