Smooth muscle potassium channel

Smooth muscle potassium channels are a functionally diverse superfamily of ion channels that allow potassium ions to move across the cell membrane in smooth muscle cells. This movement generates an outward current that hyperpolarizes the cell membrane, reduces smooth muscle excitability, and leads to muscle relaxation. In smooth muscle, the major potassium channels include voltage-gated (Kv, notably Kv7/KCNQ), large-conductance calcium-activated (BKCa/Slo1), ATP-sensitive (KATP), and inward-rectifier (Kir) channels. These channels regulate vascular, airway, bladder, and uterine tone. Faulty or dysregulated potassium channel function contributes to diseases such as hypertension, asthma, and bladder instability. Several approved or experimental drugs target these potassium channels to modulate smooth muscle physiology in the treatment of cardiovascular, respiratory, and urinary disorders

Other names

Kv channel (in smooth muscle)voltage-gated potassium channel (Kv7, KCNQ)calcium-activated potassium channel (BKCa, Slo1)ATP-sensitive potassium channel (KATP)inward-rectifier potassium channel (Kir)

Channel openers induce hyperpolarization and smooth muscle relaxation; channel blockers cause depolarization, increased intracellular calcium, and contraction