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神经肌接头是位于前角细胞的神经末梢和横纹肌纤维之间的突触后部,两者均系高度专门化地传递神经至肌肉间的电信号。神经末梢长2～3μ,外被以Schwann 细胞,但无髓鞘,它分为复杂的细支止于肌纤维表面的丛陷处而形成突触前终板。轴浆运输周围神经代谢所需的酶以供应神经末梢。神经肌肉传递中最重要的是胆碱—乙酰基转移酶,它是从乙酰辅酶A 及胆碱合成乙酰胆碱的中间物质。虽然某些胆碱可以从细胞体向周围输送,然而其中大多数是直接被神经末梢所吸收。神经末梢中的线粒体为这一代谢过程提供能量。
The neuromuscular junction is the posterior part of the synapse between the nerve terminals of the anterior horn cells and the striated muscle fibers, both of which transfer the nerve-to-muscle electrical signals highly specialized. Nerve endings 2 ~ 3μ long, the outer Schwann cells, but no myelin sheath, it is divided into complex fine branches in the muscle fibers to the surface of the depression and the formation of presynaptic end plate. Axoplasm transports nerve enzymes required by peripheral nerves to supply nerve endings. The most important factor in neuromuscular transmission is choline-acetyltransferase, which is an intermediate for the synthesis of acetylcholine from acetyl-CoA and choline. Although some choline can be delivered from the cell body to the surroundings, most of it is absorbed directly by nerve endings. Mitochondria in nerve endings provide energy for this metabolic process.