Voltage-gated calcium channel and voltage-gated sodium channel (VGCC (for Voltage-gated calcium channel), VGSC (for Voltage-gated sodium channel); alternately, CaV (for calcium), NaV (for sodium))

Voltage-gated calcium channels (VGCCs) and voltage-gated sodium channels (VGSCs) are structurally related transmembrane proteins that form ion-conducting pores in the plasma membranes of excitable cells such as neurons, muscle cells, and endocrine cells. Their activity is triggered by changes in membrane potential: sodium channels open rapidly to allow sodium influx, initiating the action potential; calcium channels open in response to depolarization, enabling calcium entry that couples electrical activity to numerous downstream cellular functions—most notably neurotransmitter/hormone secretion, muscle contraction, and gene expression. Genetic or acquired dysfunction of these channels (channelopathies) can result in a wide range of neurological, muscular, and cardiac diseases. Both channel types are major pharmacological drug targets, with blockers, modulators, and subtype-selective inhibitors widely used in medicine.

Other names

Voltage-dependent calcium channel (VDCC)CaV channelVoltage-gated sodium channel (VGSC)NaV channelCa2+ channel, sodium channelHigh-voltage-activated calcium channel (for VGCC subtypes)

Channel blockade/inhibition: Drugs can inhibit ion flux by plugging the channel pore or by stabilizing inactivated states (classic mechanism for both CaV and NaV). Subtype-selective inhibition: Targeting specific channel subtypes for tissue-selectivity Modulation of gating kinetics: Some drugs prolong the inactivated state or alter voltage sensitivity