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calcium channel
calcium channel A calcium channel is a voltage-dependent protein in the cell membrane that lets calcium ions pass selectively into or out of cells.
A calcium channel is a voltage-dependent protein in the cell membrane that lets calcium ions pass selectively into or out of cells. Different types are grouped by how they open and close, what ions they favor, and how they respond to drugs or toxins, with some found widely in the cardiovascular and central nervous systems and others mainly in neurons.