Vascular ATP-sensitive potassium channel (KATP) (Vascular KATP channel)

Vascular ATP-sensitive potassium (KATP) channels are hetero-octameric protein complexes located in the plasma membrane of vascular smooth muscle cells, primarily composed of four inward-rectifier potassium channel 6.1 (Kir6.1) subunits and four sulfonylurea receptor 2B (SUR2B) subunits [1, 2]. These channels serve as critical metabolic sensors that couple the intracellular energetic state, specifically the ATP/ADP ratio, to the membrane potential, thereby regulating vascular tone and systemic blood pressure [3]. Under conditions of metabolic stress or pharmacological activation, the opening of these channels allows for potassium efflux, which hyperpolarizes the cell membrane and prevents the activation of L-type voltage-gated calcium channels [4]. This reduction in calcium entry leads to the relaxation of vascular smooth muscle and subsequent vasodilation [5]. Clinically, these channels are the primary target for potassium channel openers like minoxidil, used in treating refractory hypertension, and their dysfunction is implicated in genetic disorders such as Cantú syndrome and cardiovascular pathologies like Prinzmetal angina [6, 7].

Other names

Vascular K-ATP channelKir6.1/SUR2B channelATP-sensitive inward rectifier potassium channel

Activation of the channel leads to potassium efflux and membrane hyperpolarization, which inhibits voltage-gated calcium channels, reduces intracellular calcium, and causes vascular smooth muscle relaxation.