Potassium Channel (ATP-sensitive) (KATP)

ATP-sensitive potassium channels (KATP channels) are a class of potassium ion channels that couple the metabolic state of a cell to its electrical activity. They are hetero-octameric complexes composed of four pore-forming Kir6.x subunits (Kir6.1 or Kir6.2) and four regulatory sulfonylurea receptor (SURx) subunits (SUR1, SUR2A, or SUR2B). The channel's activity is regulated by intracellular ATP and ADP levels, with high ATP/ADP ratios closing the channel and low ratios opening it. KATP channels play crucial roles in various tissues, including pancreatic beta cells (insulin secretion), cardiac myocytes (protection during ischemia), and vascular smooth muscle (regulation of vascular tone). Mutations in genes encoding KATP channel subunits can cause diseases such as congenital hyperinsulinism or neonatal diabetes.

Other names

ATP-sensitive potassium channelKATP channel

Modulation of channel opening probability in response to intracellular ATP/ADP ratio. Sulfonylureas inhibit the channel by binding to the SUR subunit. Diazoxide and related compounds increase channel opening probability.