Sulfonylurea receptor 2-containing ATP-sensitive potassium channel complex (SUR2-KATP) (SUR2-KATP channel)

SUR2-containing KATP channel complexes are hetero-octameric ion channels that serve as critical metabolic sensors, linking the cellular energetic state to membrane excitability [PubMed: 15131018]. These complexes consist of four pore-forming inward-rectifier potassium channel subunits (typically Kir6.1 or Kir6.2) and four regulatory sulfonylurea receptor 2 (SUR2) subunits, the latter encoded by the ABCC9 gene [UniProt: P59768]. SUR2 exists in two major isoforms: SUR2A, which is predominantly expressed in cardiac and skeletal muscle, and SUR2B, which is found in vascular and non-vascular smooth muscle [PubMed: 9159554]. These channels play a vital role in cardiovascular physiology, where they regulate vascular tone and provide cytoprotection during periods of metabolic stress or ischemia [PubMed: 11880371]. Pharmacologically, these complexes are the primary targets for potassium channel openers such as minoxidil and nicorandil, which induce vasodilation by promoting channel opening and subsequent membrane hyperpolarization [StatPearls: NBK539895]. Mutations in the subunits of these complexes are associated with clinical conditions including Cantu syndrome, characterized by hypertrichosis and cardiovascular abnormalities, and dilated cardiomyopathy [PubMed: 22703874].

Other names

ABCC9-containing KATP channelSUR2/Kir6.x complexATP-sensitive potassium channel (SUR2 type)

Potassium channel opening (activator) or Potassium channel blocking (inhibitor)