Mitochondrial nitric oxide synthase: Biological function / 第二军医大学学报

ABSTRACT

Increasing evidences have shown the existance of a mitochondrial nitric oxide synthase (mtNOS), which binds to the matrix face of the mitochondrial inner membrane and produces nitric oxide (NO) through a Ca2+ sensitive pathway. Under physiological condition, the NO catalyzed by mtNOS regulates mitochondrial oxygen consumption and transmembrane potential via reversible competition with cytochrome C oxidase. The reaction of NO with superoxide anion, which was produced by mitochondrial respiratory chain, yields peroxynitrite. Peroxynitrite irreversibly modifies susceptible targets in mitochondria and induces oxidative and/or nitrative stress. In addition, NO has also been implicated in the programmed cell death. This article reviews the current understanding of mtNOS's role in the regulation of mitochondrial functions.