神经元的存活对靶组织的依赖性虽然随年龄而改变,但这种依赖关系从胚胎期开始一直延续到生后.一些实验证明,切断躯体运动神经元的轴突,就会引起运动神经元尼氏体的溶解,并发生生物化学及电生理的改变.但是,如果切断交感神经节后纤维的同时,用神经生长因子(NGF)处理切断纤维的近侧端,则可防止节细胞尼氏体的溶解.这些资料说明,轴突切断而引起的神经细胞的退变反应,可能是神经诱向因子供应受到障碍的结果. Although the dependence of neuronal survival on target tissues varies with age, this dependence continues from embryonic to postnatal.3 Some experiments have demonstrated that the axons of somatic motoneurons can cause motor neurons Niger’s body lysis, and biochemical and electrophysiological changes occur, but if you cut off the sympathetic postganglionic fibers, while the use of nerve growth factor (NGF) to cut off the proximal side of the fiber, you can prevent the NIH These data suggest that degeneration of neurons caused by axonal cleavage may be the result of an impaired supply of neurotrophic factors.