ATP-Sensitive Potassium Channel (KATP channel)

The KATP channel is an octameric complex composed of four pore-forming Kir6.x subunits and four regulatory sulfonylurea receptor (SURx) subunits. It links cellular metabolism to membrane excitability by regulating K+ efflux in response to intracellular ATP and ADP levels. This channel plays crucial roles in various tissues including pancreatic β cells, cardiac muscle, vascular smooth muscle, skeletal muscle, and the brain, affecting processes such as insulin secretion, vasodilation, and protection against ischemia.

Other names

ATP-regulated potassium channelKir6.x/SURx complexKATP

Sulfonylureas inhibit KATP channels via binding to SUR subunits, leading to membrane depolarization and insulin release. KATP channel openers like Pinacidil activate the channel leading to hyperpolarization and smooth muscle relaxation.