N-type calcium channel

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Illustration of the major elements in a prototypical synapse. Synapses allow nerve cells to communicate with one another through axons and dendrites, converting electrical impulses into chemical signals.

Neuron A (transmitting) to neuron B (receiving)
1. Mitochondrion
2. Synaptic vesicle with neurotransmitters
3. Autoreceptor
4. Synapse with neurotransmitter released (serotonin)
5. Postsynaptic receptors activated by neuro-transmitter (induction of a postsynaptic potential)
6. Calcium channel
7. Exocytosis of a vesicle
8. Recaptured neurotransmitter

The N-type calcium channel is a type of voltage-dependent calcium channel. Like the others of this class, the α1 subunit is the one that determines most of the channel's properties.

N-type ('N' for neuron) calcium channels are found primarily at presynaptic terminals and are involved in neurotransmitter release. Strong depolarization by an action potential causes these channels to open and allow influx of Ca²⁺, initiating vesicle fusion and release of stored neurotransmitter. N-type channels are blocked by ω-conotoxin.

The analgesic drug ziconotide inhibits N-type channels.

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• MeSH N-Type+Calcium+Channel