The mechanism(s) of hypoxic pulmonary vasoconstriction: potassium channels, redox O(2) sensors, and controversies.
Hypoxic pulmonary vasoconstriction matches perfusion to ventilation and optimizes systemic oxygenation. Alterations in PO(2) are sensed by a vascular redox O(2) sensor in the pulmonary artery smooth muscle cell, probably within the mitochondria. This creates a signal that modulates redox-sensitive K(+) channels, thereby controlling membrane potential, Ca(2+) entry, and tone.
Archer
Stephen
S
Department of Medicine (Cardiology) and the Vascular Biology Group, University of Alberta, Edmonton, Alberta T6G 2B7, Canada.
Michelakis
Evangelos
E
D002628:Chemoreceptor Cells / Q000502:physiology; D006801:Humans; D000860:Hypoxia / Q000378:metabolism* / Q000503:physiopathology; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism*; D015221:Potassium Channels / Q000378:metabolism*; D011652:Pulmonary Circulation / Q000502:physiology*; D014661:Vasoconstriction / Q000502:physiology*
D015221:Potassium Channels; D010100:Oxygen