neuromuscular junction

neuromuscular junction n the junction of an efferent nerve fiber and the muscle fiber plasma membrane called also myoneural junction

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the meeting point of a nerve fibre and the muscle fibre that it supplies. Between the enlarged end of the nerve fibre (motor end-plate) and the membrane of the muscle is a gap across which a neurotransmitter must diffuse from the nerve to trigger contraction of the muscle.

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the site of apposition of a motor end plate and the subneural cleft of the skeletal muscle fiber that it innervates. After the nerve is excited, the excitatory neurotransmitter acetylcholine is released from the axon terminal when the nerve is excited, diffuses across the synaptic cleft, and reversibly binds to receptor molecules on the muscle fiber surface, causing the initiation of an action potential that propagates along the muscle fiber and causes it to contract. Called also myoneural j.