Reactome: A Curated Pathway Database

Presynaptic depolarization and calcium channel opening

Stable Identifier
R-HSA-112308
Type
Pathway
Species
Homo sapiens
Locations in the PathwayBrowser
Summation

Action potentials are used in neurons to conduct signals along the axon and occur in electrically excitable cells like neurons and cardiac muscle cells. The action potentials travel in a wave along the membrane causing the voltage sensitive channels to open to allow influx of Na+ thereby causing the conduction of the signal along the axon. The resting membrane potential of cells including neurons is -70mv. An action potential is generated by a change in the membrane potential from -70mv to +40mv when voltage gated ion channels open altering membrane permeability to Na+ and K+. The action potential travels down the axon and reaches the pre-synaptic terminal depolarizing the membrane in the pre-synaptic terminal. The depolarization causes the voltage-gated Ca2+ channels to open allowing the influx of Ca2+ that signals the release of neurotransmitter into the synaptic cleft.

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Orthologous Events