Inward Rectifier Potassium Channel (Kir)

Inward rectifier potassium channels (Kir channels) are a family of potassium-selective ion channels that allow potassium ions (K⁺) to move more easily into the cell than out of it. This property, known as "inward rectification," distinguishes them from other K⁺ channels that typically favor outward current. They play crucial roles in setting resting membrane potential, regulating heart rate, insulin secretion, and renal potassium handling. Dysfunction can lead to various channelopathies and diseases.

Other names

Kir channelsInwardly Rectifying Potassium Channels

Inward rectification via Mg²⁺/polyamine block at depolarized potentials. Activation requires PIP₂.