Hypoxic pulmonary vasoconstriction: role of voltage-gated potassium channels.
Activity of voltage-gated potassium (Kv) channels controls membrane potential, which subsequently regulates cytoplasmic free calcium concentration ([Ca2+]cyt) in pulmonary artery smooth muscle cells (PASMCs). Acute hypoxia inhibits Kv channel function in PASMCs, inducing membrane depolarization and a rise in [Ca2+ ]cyt that triggers vasoconstriction. Prolonged hypoxia inhibits expression of Kv channels and reduces Kv channel currents in PASMCs. The consequent membrane depolarization raises [Ca2+]cyt, thus stimulating PASMC proliferation. The present review discusses recent evidence for the involvement of Kv channels in initiation of hypoxic pulmonary vasoconstriction and in chronic hypoxia-induced pulmonary hypertension.
Sweeney
M
M
Department of Medicine, University of California, San Diego, California, USA. xiyuan@ucsd.edu
Yuan
J X
JX
D000818:Animals; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology*; D024642:Potassium Channels, Voltage-Gated / Q000502:physiology*; D011652:Pulmonary Circulation; D014661:Vasoconstriction
D024642:Potassium Channels, Voltage-Gated