Comparative anatomy of the axon regenration after spinal cord injury models

与哺乳动物不同的是，非哺乳动物脊髓损伤后会发生损伤部位以外的自发神经再生，从而使运动活动恢复良好。在金鱼半切面模型中，损伤部位以外的再生轴突穿过疤痕中形成的层粘连蛋白阳性管状结构。我们证实这些管状结构是由胶质纤维和基底膜形成的，它们与轴突一起进入疤痕，在金鱼压缩模型中也观察到类似的再生过程。另一方面，在两栖动物模型中，损伤部位以外的再生轴突避开了疤痕组织，这表明该模型与金鱼模型有很大不同。

In contrast to mammals, spontaneous nerve regeneration beyond the lesion site occurs in non-mammals after spinal cord lesions, resulting in the good recovery of locomotive activities. In a goldfish hemisection model, regenerating axons beyond the lesion site pass through the laminin-positive tubular structures formed in the scar. We confirmed that these tubular structures were formed by the glial fibers and the basement membrane, which entered the scar in combination with the axons, Similar regenerative processes were observed also in a goldfish compression model. In amphibian models, on the other hand, the regenerating axons beyond the lesion site avoid the scar tissue, suggesting that this model is quite different from the goldfish model.