Differentiated Bronchiolar Epithelium in Alveolar Ducts of Rats Exposed to Ozone for 20 Months

Details

• Personal Author:
  Cederdahl-Demmler J ; Dodge DE ; Haselton CJ ; Mellick PW ; Peake J ; Pinkerton KE ; Plopper CG ; Singh G ; Wong VJ
• Description:
  The effects of exposure to 1.0 ppm of ozone for twenty months were studied in male Fischer 344 rats. Light microscopic, morphometric, and immunohistological approaches were used to determine the distribution and degree of differentiation of ciliated and nonciliated bronchiolar epithelial (Clara) cells lining alveolar ducts of the central acinus, a primary target of ozone-induced lung injury. Alveolar duct pathways extending beyond the level of the most proximal alveolar outpocketing of terminal bronchioles were isolated in longitudinal profile. The distance that ciliated and nonciliated bronchiolar epithelial (Clara) cells projected down each alveolar duct pathway was determined by placing concentric arcs radiating outward from a single reference point at the level of the first alveolar outpocketing. A high degree of heterogeneity in the magnitude of bronchiolar epithelial cell extension into alveolar ducts was noted for each isolation and animal. Age-matched control animals also demonstrated variation in the degree of bronchiolar epithelial cell extension down alveolar ducts. In animals exposed to ozone, a striking similarity was noted by scanning electron microscopy in the surface characteristics of cells lining both terminal bronchioles and alveolar ducts. The presence of Clara cell secretory protein in cells of bronchioles and alveolar ducts was also detected immunohistochemically and visualized using confocal laser scanning microscopy in the reflectance mode. Well-differentiated ciliated and nonciliated bronchiolar epithelial cells were found lining alveolar septal tips and alveoli up to a depth of 1,000 mu into the pulmonary acinus after 20 months of exposure to ozone. No evidence of inflammation was present in alveolar ducts, suggesting that epithelial cell transformations in alveolar ducts is a natural consequence of lifetime exposures to oxidant gases. [Description provided by NIOSH]
• Subjects:
  Animals Irritants Lung Lung Diseases Microbiology Occupational Health Respiratory Function Tests Respiratory Hypersensitivity Respiratory System Respiratory Tract Diseases Safety

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• Keywords:
  Alveolar-cells Animal-studies Exposure-levels Exposure-limits Immunodiagnosis Lung-burden Lung-cells Lung-disorders Lung-function Lung-irritants Lung-tissue Microscopic-analysis Morphology Pulmonary-disorders Pulmonary-function Pulmonary-function-tests Pulmonary-system Pulmonary-system-disorders Respiratory-gases Respiratory-hypersensitivity Respiratory-irritants Respiratory-system-disorders

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• ISSN:
  0002-9440
• Document Type:
  Text
• Funding:
  Cooperative Agreement
• Genre:
  Journal Article
• Place as Subject:
  California ; OSHA Region 10 ; OSHA Region 3 ; OSHA Region 9 ; Pennsylvania ; Washington
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  142
• Issue:
  3
• NIOSHTIC Number:
  nn:20033329
• Citation:
  Am J Pathol 1993 Mar; 142(3):947-956
• Contact Point Address:
  K. E. Pinkerton, Department of Veterinary Anatomy and Cell Biology, School of Veterinary Medicine, University of California, Davis 95616
• CAS Registry Number:
  Ozone (CAS RN 10028-15-6)
• Federal Fiscal Year:
  1993
• Performing Organization:
  University of California - Davis
• Peer Reviewed:
  True
• Start Date:
  19900930
• Source Full Name:
  The American Journal of Pathology
• End Date:
  20020929
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:9d79d40e41ce60f00fa534a210939f0b9629ca88b666b49d8281ad8ddf1142f38ada11c1ac379356f4632505ec0ad2a8ba64b7037d6327672c9df3985ef61015
• Download URL:
  https://stacks.cdc.gov/view/cdc/188950/cdc_188950_DS1.pdf
• File Type:
  [PDF - 3.05 MB ]