Response of macaque bronchiolar epithelium to ambient concentrations of ozone

Journal Article · Wed Sep 01 04:00:00 EDT 1993 · American Journal of Pathology; (United States)

OSTI ID:5837161

Harkema, J R; Plopper, C G; Hyde, D M; George, J A; Wilson, D W; Dungworth, D L ^[1]

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1. Univ. of California, Davis (United States)

Recently, we reported that exposure to ambient concentrations of ozone, near the U.S. National Ambient Air Quality Standard (0.12 ppm), induced significant nasal epithelial lesions in a non-human primate, the bonnet monkey. The present study defines the effects of ambient concentrations of ozone on the surface epithelium lining respiratory bronchioles and on the underlying bronchiolar interstitium in these same monkeys. Bonnet monkeys were exposed to filtered air or to 0.15 or 0.30 ppm ozone 8 hours/day for 6 or 90 days. At the end of exposures, monkeys were anesthetized and killed by exsanguination. Microdissected bronchiolar airways of infusion-fixed lungs were evaluated morphometrically by light microscopy and quantitatively by scanning and transmission electron microscopy for ozone-induced epithelial changes. Hyperplasia of nonciliated, cuboidal epithelial cells and intraluminal accumulation of macrophages characterized ozone-induced lesions in respiratory bronchioles. There were no significant differences in epithelial thickness or cell numbers among ozone-exposed groups. Ozone-exposed epithelium was composed of 80% cuboidal and 20% squamous cells compared with 40% cuboidal and 60% squamous cells in filtered air controls. In addition, the arithmetic mean thickness of the surface epithelium, a measure of tissue mass per unit area of basal lamina, was significantly increased in all of the ozone-exposed groups. The number of cuboidal epithelial cells per surface area of basal lamina was increased above control values by 780% after 6 days exposure to 0.15 ppm, 777% after 90 days to 0.15 ppm, and 996% after 90 days exposure to 0.30 ppm. There was also a significant ozone-induced increase in the thickness of the bronchiolar interstitium that was due to an increase in both cellular and acellular components.

• OSTI ID: 5837161
• Journal Information: American Journal of Pathology; (United States), Journal Name: American Journal of Pathology; (United States) Vol. 143:3; ISSN AJPAA4; ISSN 0002-9440
• Country of Publication: United States
• Language: English

Related Subjects

550800 -- Morphology
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
ANIMAL TISSUES
ANIMALS
BIOLOGICAL EFFECTS
BODY
BRONCHI
CONNECTIVE TISSUE CELLS
ELECTRON MICROSCOPY
ENVIRONMENTAL EXPOSURE
EPITHELIUM
MACROPHAGES
MAMMALS
MICROSCOPY
MONKEYS
MORPHOLOGICAL CHANGES
OZONE
PHAGOCYTES
PRIMATES
RESPIRATORY SYSTEM
SCANNING ELECTRON MICROSCOPY
SOMATIC CELLS
TISSUES
TRANSMISSION ELECTRON MICROSCOPY
VERTEBRATES