Acute bronchiolar injury following nitrogen dioxide exposure: a freeze fracture study

Journal Article · Wed Dec 01 04:00:00 EST 1982 · Environ. Res.; (United States)

DOI:https://doi.org/10.1016/0013-9351(82)90041-X· OSTI ID:5173028

Case, B W; Gordon, R E; Kleinerman, J

Three groups of Syrian golden hamsters were exposed to NO/sub 2/ for 6, 24, or 48 hr to determine acute effects on intercellular junctional morphology in distal airways and alveolar epithelium. A fourth group, exposed for 48 hr, was allowed to recover for 2 days prior to sacrifice. Light and transmission electron microscopy of bronchiolar epithelium show ciliary loss and surface membrane damage, loss of ciliated cells, and epithelial flattening at 24 and 48 hr. Moderate to marked epithelial hyperplasia and nonciliated cell hypertrophy are noted after 48 hr. Some restoration of normal histoarchitecture is noted in bronchioles of animals allowed a 48-hr recovery period. Freeze fracture platinum-carbon replicas of bronchiolar epithelium show the gradual evolution of a severe disruption of tight junctional networks after 6, 24, and 48 hr of exposure. Following 2 days of ''recovery,'' bronchiolar tight junctions from animals exposed for 48 hr remain fragmented. The wide distribution of the junctionl material present suggests a regenerative process. Freeze fracture replicas of bronchial epithelium show similar fragmentation of tight junctions following 6-hr exposures. After longer intervals, however, there is a return to more normal appearances. Duration of NO/sub 2/ exposure has no systematic effect on the integrity of tight junctions in alveolar epithelium. The findings suggest that disruption of tight junctions may be an important specific determinant of increased bronchiolar epithelial permeability following brief exposures to nitrogen dioxide.

• Research Organization: Mt. Sinai School of Medicine, New York, NY
• OSTI ID: 5173028
• Journal Information: Environ. Res.; (United States), Journal Name: Environ. Res.; (United States) Vol. 29:2; 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.
ANIMAL TISSUES
ANIMALS
BIOLOGICAL EFFECTS
BODY
BRONCHI
CHALCOGENIDES
ELECTRON MICROSCOPY
EPITHELIUM
HAMSTERS
LUNGS
MAMMALS
MICROSCOPY
MORPHOLOGICAL CHANGES
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
ORGANS
OXIDES
OXYGEN COMPOUNDS
RESPIRATORY SYSTEM
RODENTS
TISSUES
TRANSMISSION ELECTRON MICROSCOPY
VERTEBRATES