RT Journal Article SR Electronic T1 Use of the NIH shift to determine the relative contribution of competing pathways of aniline metabolism in the rat. JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP 689 OP 691 VO 14 IS 6 A1 S J Grossman A1 D J Jollow YR 1986 UL http://dmd.aspetjournals.org/content/14/6/689.abstract AB The retention of tritium in urinary p-aminophenol and p-hydroxyacetanilide was determined following the administration of p-3H-aniline or p-3H-acetanilide to rats. When p-3H-aniline (1.5 mmol/kg, ip) was given to rats, the retention of tritium in urinary p-aminophenol and p-hydroxyacetanilide was 15% and 38%, respectively. Similar results were obtained following the administration of p-3H-acetanilide (1.5 mmol/kg). However, when p-3H-acetanilide was given to rats which had been pretreated with bis-(p-nitrophenyl)phosphate to block the deacetylation capacity, urinary 3H-p-hydroxyacetanilide was recovered with 53% retention of tritium. The data indicate that, at the doses studied: the primary route of aniline metabolism is via sequential acetylation and hydroxylation, and deacetylation plays a significant role in the disposition of acetanilide.