muscle cell depolarization neuromuscular junction
â¢ The neuromuscular junction is the place where the terminal portion of a motor neuron axon meets a. muscle cell membrane, separated by a synaptic cleft. â¢ An action potential arriving at the axon terminal brings about the release of acetylcholine, which. leads to depolarization of the motor end plate.verview of Neuromuscular Junction Activityâ¢ The muscle cell, including the T Tubules are polarized. Stimulation of the motor end plate on amuscle cell by acetylcholine triggers depolarization resulting in contraction of the sarcomeres.Page 6.