Glanzman D L, Kandel E R, Schacher S
Howard Hughes Medical Institute, Columbia University, College of Physicians and Surgeons, New York, New York 10032.
Neuron. 1991 Dec;7(6):903-13. doi: 10.1016/0896-6273(91)90336-x.
The adult nervous system is characterized by partial or complete morphological segregation of terminals from different afferent neurons innervating the same postsynaptic target. This segregation is thought to result, in part, from competition between the afferent terminals. To explore the role of the target cell in the spatial distribution of presynaptic inputs, the sensory neurons of Aplysia were cultured either with or without a common target motor neuron. In the presence of a common target, the outgrowth from two different sensory neurons tends to occupy separate postsynaptic regions. When cultured without a target motor neuron, processes from different sensory neurons do not segregate, but rather grow freely along one another. Thus, morphological segregation of sensory outgrowth requires interaction with a target neuron and may reflect competition between presynaptic terminals for a limited number of synaptic sites on the motor neuron, or for a postsynaptic trophic factor.
成年神经系统的特点是，支配同一突触后靶标的不同传入神经元的终末在形态上部分或完全分离。这种分离被认为部分是由传入终末之间的竞争导致的。为了探究靶细胞在突触前输入空间分布中的作用，对海兔的感觉神经元进行培养，一组有共同的靶运动神经元，另一组没有。在有共同靶标的情况下，来自两种不同感觉神经元的突起倾向于占据不同的突触后区域。当在没有靶运动神经元的情况下培养时，不同感觉神经元的突起不会分离，而是相互自由生长。因此，感觉突起的形态分离需要与靶神经元相互作用，可能反映了突触前终末对运动神经元上有限数量的突触位点或对突触后营养因子的竞争。
