Nanomolar concentrations of nitric oxide reversibly inhibit synaptosomal respiration by competing with oxygen at cytochrome oxidase

GC Brown, CE Cooper - FEBS letters, 1994 - Wiley Online Library
FEBS letters, 1994Wiley Online Library
Nitric oxide (NO) reversibly inhibited oxygen consumption of brain synaptosomes. Inhibition
was reversible, occurred at the level of cytochrome oxidase, and was apparently competitive
with oxygen, with half‐inhibition by 270 nM NO at oxygen concentrations around 145 μM
and by 60 nM NO at around 30μM O2. Isolated cytochrome oxidase was inhibited by similar
levels of NO. These levels of NO are within the measured physiological and pathological
range for a number of tissues and conditions, suggesting that NO inhibition of cytochrome …
Nitric oxide (NO) reversibly inhibited oxygen consumption of brain synaptosomes. Inhibition was reversible, occurred at the level of cytochrome oxidase, and was apparently competitive with oxygen, with half‐inhibition by 270 nM NO at oxygen concentrations around 145 μM and by 60 nM NO at around 30μM O2. Isolated cytochrome oxidase was inhibited by similar levels of NO. These levels of NO are within the measured physiological and pathological range for a number of tissues and conditions, suggesting that NO inhibition of cytochrome oxidase and the competion with oxygen may occur in vivo.
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