Cell H2O2 steady-state concentration and mitochondrial nitric oxide.

CARRERAS MC, FRANCO M.C., CONVERSO DP, FINOCCHIETTO P, GALLI S AND PODEROSO JJ

Methods in Enzymology

Año: 2005 vol. 396 p. 399 - 414

For many years, mitochondrial respiration was thought to follow an ?all or nothing? paradigm supporting the notion that in the normal O2 concentration range, respiration is mainly controlled by tissue demands. However, nitric oxide produced by cytosol or mitochondrial nitric oxide synthases adapts respiration to different physiologic conditions and increases the mitochondrial production of O2 active species that contributes to NO clearance. Because mitochondrial NO utilization is sensitive to environmental or hormonal modulation, and because diffusible active species, like H2O2, are able to regulate genes related to proliferation, quiescence, and death, we surmised that the two mechanisms converge to elicit the different responses in cell physiology.