Presynaptic cell

The presynaptic cell exclusively contains neurotransmitters such as acetylcholine and glutamate, stored in vesicles. When an action potential arrives in the presynaptic cell, voltage gated Ca²⁺ channels open allowing for the diffusion of Ca²⁺ ions into the cell causing the vesicles to undergo exocytosis, emptying their contents into the synaptic cleft. These can the bind to receptors on the postsynaptic membrane.

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