In vivo effects of nitrogen dioxide on membrane constituents in lung and liver of rats

Journal Article · Wed Feb 01 04:00:00 EST 1984 · Environ. Res.; (United States)

DOI:https://doi.org/10.1016/0013-9351(84)90004-5· OSTI ID:7003141

Mochitate, K; Kaya, K; Miura, T; Kubota, K

When rats were exposed to 10 ppm NO/sub 2/ for 7 days, the succinate-cytochrome c reductase activity of the liver decreased, reaching 77% of the control level by the fifth day. By contrast, this activity was increased by a 10-day exposure to 4 ppm NO/sub 2/ and reached 1.14-fold that of the control level at the seventh day. A reduction in the components of electron-transport systems in liver microsomes was found at both concentrations. This reduction was preferential for components of drug-metabolizing systems. The NADPH-cytochrome c reductase activity and the cytochrome P-450 content were decreased to 82% and 76%, respectively, at the fifth day of exposure to 10 ppm NO/sub 2/. Exposure to 4 ppm NO/sub 2/ also caused a significant decrease in the NADPH-cytochrome c reductase and the cytochrome P-450 content, which were lowered to 84% of the control level at the fourth and seventh days, respectively. Alterations in the components of mitochrondria and microsomes of the lung were different from those of the liver. The protein content of the lung increased to 1.18 and 1.14-fold that of the control during exposure to 10 and 4 ppm NO/sub 2/, respectively. The succinate-cytochrome c reductase activity showed a reduced value, which was 73% of the control level, 1 day after exposure to 10 ppm NO/sub 2/. Subsequently, the activity increased to 1.14-fold that of the control during exposure to 10 (at the fifth day) and 4 ppm (at the fourth day) NO/sub 2/. Components of microsomal electron-transport systems also showed a slightly elevated value during exposure to 4 ppm NO/sub 2/. Seven days after exposure, the cytochrome P-450 content was decreased to 61% of the control level, while other components were retained at control levels. A significant reduction in the cytochrome P-450 content was also observed at the exposure concentration of 1.2 ppm, but not of 0.4 ppm, at the seventh day.

• Research Organization: National Inst. for Environmental Studies, Yatabe, Japan
• OSTI ID: 7003141
• Journal Information: Environ. Res.; (United States), Journal Name: Environ. Res.; (United States) Vol. 33:1; ISSN ENVRA
• Country of Publication: United States
• Language: English

Related Subjects

560305* -- Chemicals Metabolism & Toxicology-- Vertebrates-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BIOLOGICAL EFFECTS
BODY
CELL CONSTITUENTS
CHALCOGENIDES
CYTOCHROME OXIDASE
DIGESTIVE SYSTEM
DOSE-RESPONSE RELATIONSHIPS
ELECTRON TRANSFER
ENZYME ACTIVITY
ENZYMES
GLANDS
HAEM DEHYDROGENASES
IN VIVO
LIVER
LUNGS
MAMMALS
MEMBRANES
MICROSOMES
MITOCHONDRIA
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
ORGANOIDS
ORGANS
OXIDES
OXIDOREDUCTASES
OXYGEN COMPOUNDS
PATHOLOGICAL CHANGES
RATS
RESPIRATORY SYSTEM
RODENTS
VERTEBRATES