Events at a Cholinergic Synapse

Event 5

Synaptic knob reabsorbes choline from the synaptic cleft and uses it to synthesize new molecules of ACh.

Event 3

ACh binds to receptors, depolarizes postsynaptic membrane.

Event 4

ACh is removed by AChE; AChE breaks ACh into acetate and choline.

Event 1

Action potential arrives, depolarizes synaptic terminal.

Event 2

Calcium ions enter synaptic terminal, trigger exocytosis of ACh.