The effects of a cocarcinogen, ferric oxide, on the metabolism of benzo(a)pyrene in the isolated perfused lung.
Warshawsky D; Bingham E; Niemeier RW
J Toxicol Environ Health 1984 Jan; 14(2-3):191-209
The effect of ferric-oxide (1309371) on the metabolism of benzo(a)pyrene (50328) (BaP) was examined in male white-New-Zealand- rabbits. Intraperitoneal in-vivo pretreatment with 20 milligrams per kilogram (mg/kg) BaP and intratracheal pretreatment with 10mg/kg ferric-oxide or BaP alone were injected in-vitro intratracheally in the isolated perfused lung. Metabolites were extracted and analyzed. BaP intraperitoneal or BaP intratracheal pretreatment to the whole animal followed by BaP administration to the perfused lung, in comparison to the appropriate control, significantly increased the rate of appearance of BaP metabolites in the blood. Even though BaP was given by two different routes of administration, the rates of metabolism were significantly higher than the appropriate controls in both cases. The metabolic profile showed a marked increase in the 9,10-dihydrodiol metabolite following BaP intraperitoneal or BaP intratracheal pretreatment, while there was a significant decrease in the phenols and quinones for BaP intratracheal pretreatment in comparison with no pretreatment and BaP intraperitoneal pretreatment. In-vivo pretreatment with ferric- oxide or BaP resulted in an increase in the total rate of metabolism of BaP while the in-vitro administration of ferric-oxide with BaP caused a decrease in the total metabolic ability. The authors conclude that ferric-oxide enhances dihydrodiol formation of BaP and depresses non extractable materials. Ferric-oxide interacts with BaP by altering the rate and pattern of metabolism.
NIOSH-Author; Heavy-metals; Drug-interaction; Polycyclic-aromatic-hydrocarbons; Medical-research; Animal-studies; Metabolic-study; Analytical-chemistry; Biotransformation; Chemical-composition; Reaction-rates
Journal of Toxicology and Environmental Health