4-Hydroxylation of nitrofurantoin in the rat. A 3-methylcholanthrene-inducible pathway of a relatively nontoxic compound.
When nitrofurantoin was administered daily to rats, the urinary excretion of unmetabolized drug was significantly decreased after induction by 3-methylcholanthrene or beta-naphthoflavone, but was not altered after treatment with phenobarbital. In urine samples taken 36 hr after a single dose of 14C-nitrofurantoin in rats induced with 3-methylcholanthrene, the total excretion of radioactivity (30% of dose) was the same as in noninduced rats. The proportion of unchanged nitrofurantoin, however, was only 33% of the radioactivity recovered in urine from 3-methylcholanthrene-treated animals whereas in urine from control animals 76% of the activity could be attributed to the unmetabolized drug. In 6-hr urine samples one metabolite was present to a detectable extent only in urine from 3-methylcholanthrene-treated animals. The metabolite was identified as the 4-hydroxy derivative of nitrofurantoin. 4-Hydroxylation of nitrofurantoin may find use as indicator reaction for a 3-methylcholanthrene-type induction state under in vivo conditions.
D000818:Animals; D001571:Benzoflavones; D002851:Chromatography, High Pressure Liquid; D006900:Hydroxylation; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D013058:Mass Spectrometry; D008748:Methylcholanthrene / Q000494:pharmacology; D009582:Nitrofurantoin / Q000652:urine*; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D019324:beta-Naphthoflavone
D001571:Benzoflavones; D008748:Methylcholanthrene; D019324:beta-Naphthoflavone; D009582:Nitrofurantoin; D010634:Phenobarbital