Analysis of the pathways of nitric oxide utilization in mitochondria.
The regulatory role that mitochondria play in cell dysfunction and cell-death pathways involves the concept of a complex and multisite regulation of cellular respiration and energy production signaled by cellular and intercellular messengers. Hence, the role of nitric oxide, as a physiological regulator acting directly on the mitochondrial respiratory chain acquires further relevance. This article provides a survey of the major regulatory roles of nitric oxide on mitochondrial functions as an expression of two major metabolic pathways for nitric oxide consumption: a reductive pathway, involving mitochondrial ubiquinol and yielding nitroxyl anion and an oxidative pathway involving superoxide anion and yielding peroxynitrite. The modulation of the decay pathways for nitrogen- and oxygen-centered radicals is further analyzed as a function of the redox transitions of mitochondrial ubiquinol. The interplay among these redox processes and its implications for mitochondrial function is discussed in terms of the mitochondrial steady-state levels (and gradients) of nitric oxide and superoxide anion.
Department of Molecular Pharmacology & Toxicology, School of Pharmacy, University of Southern California, Los Angeles 90089-9121, USA.
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Cadenas
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Poderoso
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Antunes
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Boveris
D000818:Animals; D005609:Free Radicals; D006801:Humans; D008928:Mitochondria / Q000378:metabolism*; D009569:Nitric Oxide / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D013481:Superoxides / Q000378:metabolism
D005609:Free Radicals; D013481:Superoxides; D009569:Nitric Oxide