NaV1.5 | sodium voltage-gated channel alpha subunit 5
Alpha subunits consist of four homologous domains (I-IV) with six transmembrane alpha helices (S1–S6) and a pore-forming loop. One a subunit may associate with 1 or 2 b subunits to make up the channel.
NaV1.5: Background Information
NaV1.5 is found primarily in cardiac muscle, where it mediates the fast influx of Na+-ions (INa) across the cell membrane, resulting in the fast depolarization phase of the cardiac action potential. As such, it plays a major role in impulse propagation through the heart.. NaV1.5 is a TTX-resistent sodium channel.
Cardiac myocytes, uninnervated skeletal muscle, central neurons, gastrointestinal smooth muscle cells and Interstitial cells of Cajal
Myocardial conduction, generation of action potentials and cell excitability
Romano-Ward, Brugada syndrome, Jervell, Lange-Nielsen, Long QT syndrome (LQT3), pain, cancer, gastrointestinal: Irritable bowel syndrome
b1, b2, b3, b4
β1, β2, β3, β4 subunit, syntrophin, NEDD4, NEDD4L, WWP2, calmodulin
Aconitine, veratridine, α-scorpion toxin, ATX-II, saxitoxin, tetrodotoxin, lidocaine
Patch Clamp: whole cell, room temperature, State- and use-dependence
NaV channel analysis requires GigaOhm seals and a stable and low access resistance
International Union of Pharmacology. XLVII. Nomenclature and Structure-Function Relationships of Voltage-Gated Sodium Channels. Pharmacol Rev 57: 397–409, Catterall, et al. 2005