title: The pathobiochemistry of nitrogen dioxide.
abstract: Nitrogen dioxide (*NO2) is an oxidizing free radical which can initiate a variety of destructive pathways in living systems, and several diseases are suspected to be connected with both exogenously and endogenously formed *NO2. Peroxynitrite (ONOO-/ONOOH) is believed to be an important endogenous source of *NO2 radicals, but other sources, among them enzymatically ones, have been identified recently. It also became clear during the last few years that in vivo formation of 3-nitrotyrosine strictly depends on the availability of *NO2 radicals. Since nitrogen dioxide is a very toxic compound an arsenal of antioxidants (e.g. vitamin C, glutathione, vitamin E, and beta-carotene) must eliminate this harmful radical in vivo. Here the recently identified superoxide (O2*-)-dependent formation of peroxynitrate (O2NOO-) and the central role of vitamin C are of special importance.
authors.affiliation: Institut für Physiologische Chemie, Universitäts-klinikum, Essen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Kirsch
authors.forename: Hans-Gert
authors.initials: HG
authors.lastname: Korth
authors.forename: Reiner
authors.initials: R
authors.lastname: Sustmann
authors.forename: Herbert
authors.initials: H
authors.lastname: de Groot
mesh_terms: D000818:Animals; D006801:Humans; D009585:Nitrogen Dioxide / Q000737:chemistry / Q000633:toxicity*; D010083:Oxidants, Photochemical / Q000737:chemistry / Q000633:toxicity; D030421:Peroxynitrous Acid / Q000494:pharmacology
chemical_list: D010083:Oxidants, Photochemical; D030421:Peroxynitrous Acid; D009585:Nitrogen Dioxide