Whitington P M, Seifert E
Dev Biol. 1984 Dec;106(2):438-49. doi: 10.1016/0012-1606(84)90243-4.
Metathoracic limb buds have been unilaterally ablated from locust embryos at 25 to 30% of embryonic development and the effect of this operation on the axon morphology of the motorneuron fast extensor tibiae (FETi) observed at later embryonic stages. In control embryos this neuron sends a single axon out the main leg nerve, nerve 5, to the extensor tibiae muscle in the femur. In limb ablated embryos the axon of FETi is found in a wide variety of aberrant peripheral nerve pathways and projects to a wide range of foreign muscles. There is a degree of apparent selectivity, but no rigid hierarchy, in the choice of pathway and muscle made by FETi. A high degree of variability is found between one embryo and another in the extent and pattern of axon branching. The axon of FETi is generally found in pathways that correspond to nerves in control embryos but on occasion grows along novel routes. An anteriorly directed dendritic branch, seldom seen in control FETi neurons, is frequently seen in experimental FETis. These findings are discussed in terms of the rules for specific axon growth in normal development.
在蝗虫胚胎发育至25%至30%时，对其胸后肢芽进行单侧切除，并观察该手术对胚胎后期运动神经元快速胫节伸肌（FETi）轴突形态的影响。在对照胚胎中，该神经元发出一条单一轴突，通过主腿神经（第5神经）延伸至股骨中的胫节伸肌。在肢芽切除的胚胎中，FETi的轴突出现在多种异常的外周神经通路中，并投射到广泛的异常肌肉。FETi在选择通路和肌肉时存在一定程度的明显选择性，但没有严格的等级制度。在不同胚胎之间，轴突分支的程度和模式存在高度变异性。FETi的轴突通常出现在与对照胚胎中的神经相对应的通路中，但偶尔也会沿着新的路径生长。在实验性FETi中经常可以看到一个向前的树突分支，而在对照FETi神经元中很少见。本文根据正常发育中特定轴突生长的规则对这些发现进行了讨论。
