Voltage-dependent calcium channels ( VDCCs ) are a group of voltage-gated ion channels found in the membrane of excitable cells ( e.g., muscle, glial cells, neurons, etc.) with a permeability to the calcium ion Ca 2+. These channels are slightly permeable to sodium ions, so they are also called Ca 2+ -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. The concentration of calcium (Ca 2+ ions) is normally several thousand times higher outside of the cell than inside. Activation of particular VDCCs allows Ca 2+ to rush into the cell, which, depending on the cell type, results in activation of calcium-sensitive potassium channels, muscular contraction, excitation of neurons, up-regulation of gene expression, or release of hormones or neurotransmitters. VDCCs have been immunolocalized in the zona glomerulosa of normal and hyperplastic human adrenal, as well as in aldosterone -producing adenomas (APA), and in the latter T-type VDCCs correlated with plasma aldosterone levels of patients. Excessive activation of VDCCs is a major component of excitotoxicity, as severely elevated levels of intracellular calcium activates enzymes which, at high enough levels, can degrade essential cellular structures. (hgnc.genefamily:1512)



None available.

Incoming Relations

Identifier Name Relation
HGNC:1395 CACNA1H isa
HGNC:1388 CACNA1A isa
HGNC:1397 CACNA1S isa
HGNC:1389 CACNA1B isa
HGNC:1393 CACNA1F isa
HGNC:1391 CACNA1D isa
HGNC:1396 CACNA1I isa
HGNC:1394 CACNA1G isa
HGNC:1390 CACNA1C isa
HGNC:1392 CACNA1E isa

Outgoing Relations

Relation Identifier Name