Long-term effects of ozone and nitrogen dioxide on the metabolism and population of alveolar macrophages

Journal Article · Wed Apr 01 04:00:00 EST 1992 · Journal of Toxicology and Environmental Health; (United States)

DOI:https://doi.org/10.1080/15287399209531615· OSTI ID:5320573

Mochitate, K; Ishida, K; Ohsumi, T; Miura, T ^[1]

---

1. Environmental Health Sciences Division, National Institute for Environmental Studies, Ibaraki, (Japan)

To investigate how alveolar macrophages adapt themselves to oxidative pollutants in the long term, rats were exposed to a strong oxidant, ozone (O3), or a weak oxidant, nitrogen dioxide (NO2), for a maximum duration of 12 wk. After exposures, alveolar macrophages were collected by pulmonary lavage. Throughout 11 wk of exposure to 0.2 ppm O3, the specific activities of glucose-6-phosphate dehydrogenase (G6PDH) and glutathione peroxidase of the peroxidative metabolic pathway and pyruvate kinase and hexokinase of the glycolytic pathway were 40-70% elevated over the controls in alveolar macrophages. The population of alveolar macrophages was consistently 60% higher than the controls. The small-sized macrophages, immature macrophages, preferentially increased. To the contrary, the thymidine incorporation per cell was always 20-30% lower than in the controls, although the total incorporation remained unchanged. No infiltration of polymorphonuclear leukocytes occurred. By 12 wk of exposures to 1.2 and 4.0 ppm NO2, the population of alveolar macrophages increased 30% over the control. Among the enzymes examined, however, only the G6PDH activity increased 10% for 4.0 ppm NO2. No increase in the enzyme activities occurred for 1.2 ppm NO2. Based on these results, alveolar macrophages adapt themselves to the long-term exposure of O3 or NO2 by recruiting immature macrophages through an apparent influx of monocytes. During the exposure to O3, the peroxidative metabolic and glycolytic pathways are enhanced persistently in alveolar macrophages, whereas both pathways were not enhanced by the exposures to NO2.

• OSTI ID: 5320573
• Journal Information: Journal of Toxicology and Environmental Health; (United States), Journal Name: Journal of Toxicology and Environmental Health; (United States) Vol. 35:4; ISSN JTEHD; ISSN 0098-4108
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
ANIMALS
ATP
BIOLOGICAL ADAPTATION
BIOLOGICAL PATHWAYS
CHALCOGENIDES
CONNECTIVE TISSUE CELLS
DNA
DOSE-RESPONSE RELATIONSHIPS
ENZYME ACTIVITY
ENZYMES
GLYCOLYSIS
HEMIACETAL DEHYDROGENASES
HEXOKINASE
LACTATE DEHYDROGENASE
LAVAGE
MACROPHAGES
MAMMALS
METABOLISM
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
NUCLEIC ACIDS
NUCLEOTIDES
ORGANIC COMPOUNDS
OXIDES
OXIDOREDUCTASES
OXYGEN COMPOUNDS
OZONE
PEROXIDASES
PHAGOCYTES
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
PROTEINS
RATS
RODENTS
SOMATIC CELLS
TOXICITY
TRANSFERASES
VERTEBRATES