In vivo oxidation of reduced nicotinamide-adenine dinucleotide phosphate by paraquat and diquat in rat lung.
Intravenous injection of rats with 156 mumol/kg of paraquat or 140 mumol/kg of diquat produced, within 60 min, a sharp drop in the ratios of NADPH to NADP in lung. The effect persisted for a time period of at least 24 h. Exposure to 100% oxygen enhanced the toxicity of both compounds without substantially amplifying changes in the NADPH/NADP ratio. Lungs retained the capability to synthesize adenine nucleotides de novo. Electron microscopic studies showed that both paraquat and diquat damage type I alveolar cells, but only paraquat produces type II cell lesions. Although bipyridylium herbicides produce acute oxidation of NADPH in vivo, there seems not to exist a straightforward relationship between this event and cell damage.
D000818:Animals; D004247:DNA / Q000378:metabolism; D004178:Diquat / Q000378:metabolism* / Q000494:pharmacology; D007700:Kinetics; D008168:Lung / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D009249:NADP / Q000378:metabolism*; D010084:Oxidation-Reduction; D010269:Paraquat / Q000378:metabolism* / Q000494:pharmacology; D011726:Pyridinium Compounds / Q000378:metabolism*; D051381:Rats
D011726:Pyridinium Compounds; D009249:NADP; D004247:DNA; D004178:Diquat; D010269:Paraquat