title: Long-term NO2 exposure of mice in the presence and absence of vitamin E. II. Effect of glutathione peroxidase.
abstract: One hundred and twenty female mice fed diets containing various levels of vitamin E were continuously exposed to 0.5 ppm, 1.0 ppm nitrogen dioxide (NO2), and filtered air for 17 months. Blood, lung, and liver tissues were assayed for glutathione peroxidase (GSH-peroxidase) activity. Exposure to 0.5 ppm NO2 did not affect blood and lung GSH-peroxidase activity; 1.0 ppm NO2 exposure, however, caused suppression of the enzyme. A combination of vitamin E deficiency and 1.0 ppm NO2 exposure resulted in the lowest GSH-peroxidase activities in the blood and lung. High levels of vitamin E in the diet resulted in elevated GSH-peroxidase in the blood and lung. Liver GSH-peroxidase activity was unaffected by either dietary vitamin E or NO2 exposure. No inverse relationship was found between GSH-peroxidase levels and concentrations of organic solvent soluble lipofuscin pigments present in tissues.
mesh_terms: D000818:Animals; D004032:Diet; D004781:Environmental Exposure; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008168:Lung / Q000201:enzymology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009585:Nitrogen Dioxide / Q000494:pharmacology*; D010544:Peroxidases / Q000378:metabolism*; D013997:Time Factors; D014810:Vitamin E / Q000008:administration & dosage*; D014811:Vitamin E Deficiency / Q000201:enzymology
chemical_list: D014810:Vitamin E; D010544:Peroxidases; D005979:Glutathione Peroxidase; D009585:Nitrogen Dioxide