Superoxide, nitric oxide and peroxynitrite.

Over the past several years, a large body of evidence has shown the injurious action of superoxide. However, with the discovery that most types of cells can generate nitric oxide (NO), the pathological conditions previously attributed to superoxide must to be re-examined considering the reaction of superoxide and NO. This is particularly important if there are conditions where the production of peroxynitrite is relevant, since peroxynitrite is a very potent oxidant and yielded by the reaction of superoxide and NO with a diffusion controlled rate. In this article, we reviewed various pathological conditions, focusing on the generation of these three reactive substances and demonstrated actual examples of peroxynitrite-related injuries.