title: Reduction of nitroimidazoles in model chemical and biological systems.
abstract: Some chemical and biological properties of intermediates obtained during reduction of nitroimidazoles are discussed. These include: rate data for the decay of the nitro radical-anion, stoichiometry and absorption spectra for reduction via the radical-anion or using dithionite, stoichiometry with other reducing agents, and rate of reduction by xanthine/xanthine oxidase. Increased radiosensitization by misonidazole is seen upon prolonged pre-irradiation incubation using E. coli, enabling demonstration that a freely-diffusable metabolite is responsible for this effect. Preliminary experiments designed to extend studies of the radiobiological properties of extracellularly-added metabolites to mammalian cells and the use of liver perfusion to generate metabolites are described.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D055598:Chemical Phenomena; D002621:Chemistry; D004355:Drug Stability; D004926:Escherichia coli / Q000378:metabolism; D066298:In Vitro Techniques; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D051379:Mice; D008956:Models, Chemical; D009593:Nitroimidazoles / Q000378:metabolism / Q000494:pharmacology; D010084:Oxidation-Reduction; D011838:Radiation-Sensitizing Agents / Q000378:metabolism
chemical_list: D009593:Nitroimidazoles; D011838:Radiation-Sensitizing Agents