In vivo effect of ozone inhalation on xenobiotic metabolism of lung and liver of rats

Journal Article · Tue Jan 01 00:00:00 EST 1985 · J. Toxicol. Environ. Health; (United States)

DOI:https://doi.org/10.1080/15287398509530711· OSTI ID:6228556

Takahashi, Y; Miura, T; Kubota, K

Male Jcl:Wistar rats were exposed to 0.4 and 0.8 ppm O3 daily for 7 h for 14 d to examine the effect of O3 on xenobiotic metabolism of lung and liver microsomes. An exposure to 0.4 ppm O3 did not affect the microsomal xenobiotic metabolism of either lung or liver. On the other hand, 0.8 ppm O3 increased significantly the NADPH-cytochrome P-450 reductase activity and the cytochrome P-450 content of lung microsomes. The activities of lung benzo(a)pyrene hydroxylase and 7-ethoxycoumarin O-deethylase also increased significantly on d 7, and remained at a higher level by the d 14. These results show that exposures to 0.8 ppm O3 induce the xenobiotic metabolizing systems in the lung. In the liver, after the first day of exposure to 0.8 ppm O3, a significant reduction occurred in all components of the electron-transport systems examined as well as in the microsomal protein. A significant decrease was also observed in benzo(a)pyrene hydroxylation, 7-ethoxycoumarin O-deethylation, and aniline hydroxylation. The decreased activities recovered in the following period of exposure. In contrast, the p-nitroanisole N-demethylase activity was not altered during the 14-d exposures. These results suggest that some isozymes of the hepatic cytochrome P-450 are sensitive to O3 inhalation but other(s) are resistant.

• Research Organization: National Institute for Environmental Studies, Ibaraki, Japan
• OSTI ID: 6228556
• Journal Information: J. Toxicol. Environ. Health; (United States), Vol. 6
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
OXYGENASES
ENZYME ACTIVITY
OZONE
BIOLOGICAL EFFECTS
INHALATION
EXPOSURE CHAMBERS
LIVER
LUNGS
METABOLISM
MICROSOMES
RATS
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CELL CONSTITUENTS
DIGESTIVE SYSTEM
ENZYMES
GLANDS
INTAKE
MAMMALS
ORGANOIDS
ORGANS
OXIDOREDUCTASES
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VERTEBRATES
560305* - Chemicals Metabolism & Toxicology- Vertebrates- (-1987)