ATP-sensitive potassium channel, pancreatic beta cell (KATP channel)

The ATP-sensitive potassium channel in pancreatic beta cells (KATP channel) is a crucial ion channel complex that links cell metabolism to electrical activity, coupling glucose metabolism with insulin secretion. The channel is a hetero-octamer composed of two key subunits: Kir6.2 (encoded by the KCNJ11 gene), which forms the potassium-selective pore, and SUR1 (encoded by the ABCC8 gene), which acts as the regulatory sulfonylurea receptor. In low-glucose states, the channel is open, hyperpolarizing the cell membrane and preventing insulin secretion. As glucose enters the cell and increases intracellular ATP, the channel closes, resulting in membrane depolarization, calcium influx through voltage-dependent calcium channels, and trigger of insulin release. Dysfunction of this channel due to gene mutations results in disorders such as congenital hyperinsulinism (channel stays closed, high insulin) and various forms of diabetes (channel stays open, low insulin)[1][2][3]. Drugs such as sulfonylureas close the channel to stimulate insulin release, while diazoxide opens it to reduce insulin secretion. The channel is a major pharmacological target for the treatment of diabetes and hyperinsulinism.

Other names

ATP-dependent potassium channelATP-sensitive potassium channelKATP channelPancreatic KATP channelPancreatic beta cell KATP channel

Sulfonylureas: block (inhibit) channel to stimulate insulin secretion. Diazoxide: opens (activates) the channel, inhibiting insulin secretion. Altering channel activity directly affects beta cell excitability and insulin release