Voltage-gated potassium channel subfamily D (Kv4)

The Kv4.x family, comprising Kv4.1, Kv4.2, and Kv4.3, consists of voltage-gated potassium channels that mediate the fast-inactivating A-type current (IA) in neurons and the transient outward current (Ito) in the heart (1.1.4, 1.3.1). These channels are critical for regulating the early repolarization phase of the cardiac action potential and controlling neuronal excitability, particularly in the somatodendritic regions (1.2.2, 1.3.2). Dysregulation or mutations in Kv4 channels are linked to a variety of channelopathies, including Brugada syndrome and atrial fibrillation in the cardiovascular system, as well as epilepsy, spinocerebellar ataxia, and neurodegenerative diseases like Alzheimer's in the central nervous system (1.2.1, 1.5.4). Pharmacological targeting of Kv4.x involves small-molecule inhibitors, gating modifiers, and modulators of their interaction with auxiliary subunits like KChIPs (1.4.3, 1.5.3). While they offer therapeutic potential for treating arrhythmias and hyperexcitability disorders, safety concerns such as pro-arrhythmic effects and CNS toxicity must be carefully managed (1.2.2, 1.2.3). These channels are also modulated by various intracellular signaling pathways, including phosphorylation by kinases like PKA and PKC, which further complicates their role as drug targets (1.3.1, 1.4.1).

Other names

Shal-related subfamilyKCNDA-type potassium channelShal-type potassium channelKv4.x

Inhibition of the transient outward potassium current (Ito) or A-type current (IA) through pore blocking or modulation of channel gating and auxiliary subunit interactions (1.1.3, 1.4.3).