Unraveling peroxynitrite formation in biological systems

Peroxynitrite promotes oxidative damage and is implicated in the pathophysi ology of various diseases that involve accelerated rates of nitric oxide an d superoxide formation. The unambiguous detection of peroxynitrite in biolo gical systems is, however, difficult due to the combination of a short biol ogical half-life, limited diffusion, multiple target molecule reactions, an d participation of alternative oxidation/nitration pathways. In this review , we provide the conceptual framework and a comprehensive analysis of the c urrent experimental strategies that can serve to unequivocally define the e xistence and quantitation of peroxynitrite in biological systems of differe nt levels of organization and complexity. (C) 2001 Elsevier Science Inc.