Ascorbate uptake by isolated rat alveolar macrophages and type II cells.

Details

• Personal Author:
  Castranova, Vincent ; Colby HD ; Miles PR ; Wright JR
• Description:
  Measurements were made of the intracellular ascorbate concentrations (IACs) in three fractions of isolated pneumocytes from male Sprague- Dawley-rats, specifically alveolar macrophages, type II cells, and other lung cells; and studies were carried out to determine the characteristics of ascorbate uptake in these fractions. IACs were measured by incubating the cells in media containing 0.1 millimolar (mM) ascorbate and spectrophotometrically comparing the optical densities of samples against standards. IACs were 3.2mM in alveolar macrophages and type II cells and 0.9mM in other lung cells. Ascorbate uptake was measured by means of labeled ascorbic-acid and a liquid scintillation spectrometer. The time course of ascorbate uptake in each cell type exhibited an initial minor component that was rapid and lasted less than 15 minutes, and a major component that was linear from 15 to 120 minutes. The rates of uptake during the major component decreased in the order alveolar macrophages, type II cells, and other cells. In alveolar microphages and type II cells, ascorbate influx followed saturation kinetics and was dependent on extracellular sodium and metabolic inhibitors. The authors suggest that high dietary levels of ascorbate may be useful in protecting the lung from oxidant injury. [Description provided by NIOSH]
• Subjects:
  Diet Lung Occupational Health Respiratory System Safety
• Keywords:
  Antioxidation Author Keywords: Ascorbate Transport Kinetics NIOSH-Author Oxidizers Pneumocytes Prophylaxis Pulmonary-system Transport-mechanisms
• ISSN:
  0161-7567
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  ALOSH - Appalachian Laboratory for Occupational Safety and Health
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  208-214
• Volume:
  54
• Issue:
  1
• NIOSHTIC Number:
  nn:00174879
• Citation:
  J Appl Physiol: Respir Environ Exercise Physiol 1983 Jan; 54(1):208-214
• Federal Fiscal Year:
  1983
• NORA Priority Area:
  Pulmonary System Disorders
• Peer Reviewed:
  True
• Source Full Name:
  Journal of Applied Physiology: Respiratory, Environmental and Exercise Physiology
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:cd651bbf5441a89f270e7c9730aba6d044c55a3a5b68d15a079ba6dfad8a29f897acd60c67026abdaba08a70fb103f1ca3eb62f2b52734861223a076c92601cc
• Download URL:
  https://stacks.cdc.gov/view/cdc/185334/cdc_185334_DS1.pdf
• File Type:
  [PDF - 1.59 MB ]