What happens in the motor nerve terminal during neuromuscular transmission?
When a wave of depolarization (the action potential) travels down the motor nerve and reaches its tip (the presynaptic nerve terminal), voltage-gated calcium channels in the neuronal membrane open, allowing influx of calcium ions (Ca 2+ ).
This triggers the fusion of acetylcholine (ACh)-filled vesicles with the membrane and the release of ACh into the space between the nerve and muscle membranes (the synaptic cleft)
