The pathways of oxygen in brain. II. Competitions for cytochrome c oxidase and NOS are keys to flow-metabolism coupling.
It has been well-known for many years that cerebral oxygen consumption remains constant during moderate changes of blood flow, as measured during hypo- or hypercapnia or indomethacin administration. Current models of flow-metabolism coupling link blood-brain transfer of oxygen to oxygen metabolism in mitochondria. The resulting quantitative relations between flow and metabolism reveal that a close link between diffusion and metabolism prevents the enzyme from maintaining a constant oxygen consumption when blood flow changes, unless the enzyme's affinity towards oxygen is adjusted commensurately.
Gjedde
Albert
A
D001921:Brain / Q000201:enzymology / Q000378:metabolism*; D002560:Cerebrovascular Circulation; D003576:Electron Transport Complex IV / Q000378:metabolism*; D006801:Humans; D008928:Mitochondria / Q000378:metabolism; D008959:Models, Neurological; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D012039:Regional Blood Flow
D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D003576:Electron Transport Complex IV; D010100:Oxygen