Clarke J D, Tonge D A, Holder N H
Proc R Soc Lond B Biol Sci. 1986 Feb 22;227(1246):67-82. doi: 10.1098/rspb.1986.0010.
In frogs sensory axons from the lumbar dorsal roots ascend in the dorsal column of the spinal cord to terminate in the medulla and cerebellum. The response of these axons to complete transection of the thoracic spinal cord has been analysed in Rana temporaria tadpoles at different stages of development. The presence and position of dorsal column axons were assessed by using the anterograde transport of horseradish peroxidase or by electrophysiological methods. Before developmental stage VIII, dorsal column axons can grow across the transection and reach their normal areas of termination in the brainstem. Axons that do cross the transection follow their normal pathways. From stage VIII onwards this capacity for growth is largely lost. These results are discussed in terms of the relation between neurogenesis, axon growth and axonal regeneration.
在青蛙中，来自腰背部神经根的感觉轴突在脊髓的背柱中上升，终止于延髓和小脑。在不同发育阶段的欧洲林蛙蝌蚪中，分析了这些轴突对胸段脊髓完全横断的反应。通过辣根过氧化物酶的顺行运输或电生理方法评估背柱轴突的存在和位置。在发育阶段VIII之前，背柱轴突可以穿过横断处并到达它们在脑干中的正常终止区域。确实穿过横断处的轴突沿着它们的正常路径生长。从阶段VIII开始，这种生长能力大部分丧失。根据神经发生、轴突生长和轴突再生之间的关系对这些结果进行了讨论。
