Voltage-dependent Calcium Channel
Voltage-dependent calcium channels (VDCC) are a group of voltage-gated ion channels found in excitable cells (e.g., muscle, glial cells, neurons, etc.) with a permeability to the ion Ca2+. These channels are slightly permeable to sodium ions, so they are also called Ca2+-Na+ channels, but their permeability to calcium is about 1000-fold greater than to sodium under normal physiological conditions. At physiologic or resting membrane potential, VDCCs are normally closed. They are activated (i.e., opened) at depolarized membrane potentials and this is the source of the "voltage-dependent" epithet. Activation of particular VDCCs allows Ca2+ entry into the cell, which, depending on the cell type, results in muscular contraction, excitation of neurons, up-regulation of gene expression, or release of hormones or neurotransmitters.
Other articles related to "calcium channels, calcium channel":
... cell is depolarized, it causes opening of the voltage-gated, or L-type, calcium channels ... Opening of the L-type calcium channel causes influx of extracellular Ca2+, which then binds calmodulin ... for an illustration of the signaling cascade involving L-type calcium channels in smooth muscle) ...
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