Nitrofurantoin-stimulated superoxide production by channel catfish (Ictalurus punctatus) hepatic microsomal and soluble fractions

摘要: Abstract Nitroaromatic compounds, which frequently contaminate the environment, are known to be reduced corresponding aromatic amines by fish as well mammals under anaerobic conditions. Although amine products not generally formed aerobically, “nitroreducase”-mediated redox cycling of nitroaromatics may occur these conditions, leading enhanced production a potentially toxic oxygen species, superoxide (O 2 − ). In this study, we have investigated ability channel catfish ( Ictalurus punctatus ) hepatic microsomal and soluble fractions stimulate O upon exposure model nitroaromatic compound, nitrofurantoin (NF). Two assays for production, cytochrome c reduction cyanide-insensitive consumption, were stimulated NF both fractions. These reactions partially inhibited dismutase (SOD), SOD catalase in consumption assay, providing specific evidence involvement stimulatory effect NF. Furthermore, results cofactor requirement inhibition studies suggest that enhancement was mediated NADPH-cytochrome P -450 reductase fraction xanthine oxidase fraction. findings comprehensively vitro stimulation indicated also and, therefore, suggests similar potential oxyradical-mediated toxicities species.