Voltage-gated sodium channel alpha subunits 1.1 through 1.6 (Nav1.1–Nav1.6) (Nav1.1–Nav1.6)

Voltage-gated sodium channels (Nav1.1–Nav1.6) are critical transmembrane proteins responsible for the rapid influx of sodium ions that initiates and propagates action potentials in excitable cells. This group includes isoforms primarily expressed in the central nervous system (Nav1.1, Nav1.2, Nav1.3, Nav1.6), skeletal muscle (Nav1.4), and cardiac tissue (Nav1.5). They play a fundamental role in neuronal signaling, muscle contraction, and the maintenance of heart rhythm. Mutations in the genes encoding these channels (SCN1A, SCN2A, SCN3A, SCN4A, SCN5A, SCN8A) are associated with a wide range of channelopathies, including various forms of epilepsy, cardiac arrhythmias, and periodic paralysis. Pharmacologically, these channels are the primary targets for many anticonvulsants, local anesthetics, and antiarrhythmics, which typically act by blocking the channel pore or stabilizing the inactivated state to reduce pathological hyperexcitability. However, the high sequence homology between these subtypes presents a significant challenge for drug discovery, as non-selective inhibition can lead to adverse effects such as cardiotoxicity or neurological impairment. Current research focuses on developing subtype-selective inhibitors to improve therapeutic indices and minimize off-target effects, particularly avoiding Nav1.5 to prevent cardiac complications.

Other names

SCN1ASCN2ASCN3ASCN4ASCN5ASCN8ASodium channel protein type 1 subunit alphaSodium channel protein type 2 subunit alphaSodium channel protein type 3 subunit alphaSodium channel protein type 4 subunit alphaSodium channel protein type 5 subunit alphaSodium channel protein type 8 subunit alphaVoltage-gated sodium channel alpha subunits 1.1 through 1.6VGSCNav1.1Nav1.2Nav1.3Nav1.4Nav1.5Nav1.6

Drugs targeting these channels typically act as pore blockers or gating modifiers that stabilize the inactivated state (either fast or slow inactivation), thereby reducing the frequency of action potential firing and limiting cellular hyperexcitability.