title: Reduction of niridazole by metronidazole resistant and susceptible strains of Trichomonas vaginalis.
abstract: The inhibitory effect of niridazole on hydrogen production by metronidazole-resistant (CDC-85) and susceptible (C1-NIH) Trichomonas vaginalis strains was investigated. The results show that niridazole is more effective than metronidazole in inhibiting hydrogen production by the resistant isolate. In CDC-85 aerobic inhibition requires a 4-fold increase in metronidazole concentration compared with that required anaerobically, but the corresponding factor for niridazole is only 1.5-fold. Reduction of the drug by a hydrogenosome-enriched preparation gave rise to a multiline electron spin resonance detectable signal, which is due to a nitrogen-centred radical.
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D004351:Drug Resistance; D004578:Electron Spin Resonance Spectroscopy; D006859:Hydrogen / Q000378:metabolism; D013058:Mass Spectrometry; D008795:Metronidazole / Q000378:metabolism / Q000494:pharmacology*; D009560:Niridazole / Q000378:metabolism / Q000494:pharmacology*; D010084:Oxidation-Reduction; D014246:Trichomonas vaginalis / Q000187:drug effects* / Q000378:metabolism
chemical_list: D008795:Metronidazole; D002245:Carbon Dioxide; D006859:Hydrogen; D009560:Niridazole