Nitric oxide regulates mitochondrial respiration and cell functions by inhibiting cytochrome oxidase.
Nitric oxide (NO) reversibly inhibits mitochondrial respiration by competing with oxygen at cytochrome oxidase. Concentrations of NO measured in a range of biological systems are similar to those shown to inhibit cytochrome oxidase and mitochondrial respiration. Inhibition of NO synthesis results in a stimulation of respiration in a number of systems. It is proposed that NO exerts some of its main physiological and pathological effects on cell functions by inhibiting cytochrome oxidase. Further NO may be a physiological regulator of the affinity of mitochondrial respiration for oxygen, enabling mitochondria to act as sensors of oxygen over the physiological range.
Brown
G C
GC
Department of Biochemistry, University of Cambridge, UK.
D000818:Animals; D003576:Electron Transport Complex IV / Q000037:antagonists & inhibitors*; D006801:Humans; D008928:Mitochondria / Q000378:metabolism*; D009119:Muscle Contraction; D009126:Muscle Relaxation; D018482:Muscle, Skeletal / Q000502:physiology; D009130:Muscle, Smooth / Q000502:physiology; D009569:Nitric Oxide / Q000378:metabolism / Q000502:physiology*; D010085:Oxidative Phosphorylation; D010101:Oxygen Consumption
D009569:Nitric Oxide; D003576:Electron Transport Complex IV