Effect of liver enzyme inducers on metabolite excretion in rats treated with 1-nitropyrene.
Non-induced and phenobarbital (PB) or methylcholanthrene (MC) pretreated rats were injected with 1-nitropyrene (1-NP). Mutagenic activity of urine and feces samples were compared by the Salmonella/microsome assay. The highest, indirect-acting mutagenicity was associated with urines from MC-induced rats; HPLC analysis of organic extracts of urine samples showed that the differences in mutagenic response can be ascribed to different amounts of hydroxy derivatives of N-acetylaminopyrene excreted. Monohydroxy derivatives of 1-NP, being detected in the HPLC profiles of urine from PB-induced rats only, could be responsible of the higher direct-acting mutagenic activity of these samples as compared to urine from non-induced or MC-induced rats. The excretion rate of aminopyrene, the main metabolite of 1-NP identified in rat feces samples, was not affected by inducer pretreatment.
Belisario
M A
MA
Carrano
L
L
De Giulio
A
A
Pecce
R
R
Buonocore
V
V
D000818:Animals; D001711:Biotransformation; D005243:Feces / Q000032:analysis; D007700:Kinetics; D008297:Male; D008748:Methylcholanthrene / Q000494:pharmacology*; D008862:Microsomes, Liver / Q000378:metabolism; D009152:Mutagenicity Tests; D009153:Mutagens / Q000302:isolation & purification* / Q000494:pharmacology / Q000652:urine; D009154:Mutation; D010634:Phenobarbital / Q000494:pharmacology*; D011721:Pyrenes / Q000378:metabolism* / Q000494:pharmacology / Q000652:urine; D051381:Rats; D011919:Rats, Inbred Strains; D012486:Salmonella typhimurium / Q000187:drug effects
D009153:Mutagens; D011721:Pyrenes; D008748:Methylcholanthrene; C032668:1-nitropyrene; D010634:Phenobarbital