摘要: The mechanism by which a motor nerve axon “nourishes” or maintains “trophic influence” on the muscle fiber it reaches remains unknown, despite much investigation and interest. A large body of literature, including several excellent reviews [12, 13, 15, 16] suggests that presynaptic element exerts its control in one three ways: (a) release normal transmitter, acetylcholine (ACh), (b) some aspect stimulus-evoked postsynaptic response itself, i.e., muscle, contraction, (c) other substances delivered to terminals centrifugal axoplasmic flow from neuron soma.