Increased Susceptibility of the Lungs of Hyperthyroid Rats to Oxidant Injury: Specificity of Effects

Details

• Personal Author:
  Beighley CM ; Frazer DG ; Huffman LJ ; McKinney WG ; Porter DW
• Description:
  Results from previous studies indicate that hyperthyroidism increases the risk of ozone-induced lung toxicity. This observation raised the possibility that pulmonary damage from other oxidant substances might be greater in a hyperthyroid state. To address this hypothesis, pulmonary responses to crystalline silica, a particulate with oxidant properties, were evaluated in normal or hyperthyroid adult male rats. To induce a hyperthyroid condition, time-release pellets containing thyroxine were implanted subcutaneously; control rats received placebo pellets. After 7 days, the animals were exposed to saline or silica (0.1mg/100g BW or 1.0mg/100g BW) by intratracheal instillation. Following silica treatment, there was a dose-related increase in bronchoalveolar lavage (BAL) albumin levels and neutrophil numbers. However, the effects of silica were similar in both normal and hyperthyroid rats. These findings were confirmed and contrasted with those regarding ozone (1ppm, 4h inhalation) in a subsequent experiment. The results indicated that, although exposure to either ozone or silica resulted in increases in BAL albumin levels and neutrophil numbers, only responses to ozone were enhanced in hyperthyroid rats. These findings suggest that specificity exists in regards to the modulation of oxidant-induced lung damage and inflammation by thyroid hormones. [Description provided by NIOSH]
• Subjects:
  Aluminum Silicates Animals Laboratories Lung Diseases Occupational Health Respiratory Tract Diseases Risk Assessment Risk Factors Safety Silicon Dioxide
• Keywords:
  Animal-studies Injuries Laboratory-animals Lung-disorders Pulmonary-system-disorders Respiratory-system-disorders Risk-analysis Risk-factors Silica-dusts Silicates
• ISSN:
  0300-483X
• Document Type:
  Text
• Genre:
  Journal Article
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  119-127
• Volume:
  225
• Issue:
  2
• NIOSHTIC Number:
  nn:20030884
• Citation:
  Toxicology 2006 Aug; 225(2-3):119-127
• Contact Point Address:
  Health Effects Laboratory Division, National Institute for Occupational Safety and Health, M/S 2015, 1095 Willowdale Road, Morgantown, WV 26505, USA
• Email:
  DPorter@cdc.gov
• Federal Fiscal Year:
  2006
• Peer Reviewed:
  True
• Source Full Name:
  Toxicology
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:df269a12c2478905234ee2fce5e09396a52b6664e655e6dfdecc9a49c6d6c567b7fe69e3f66981ac92c8f4a06c4e105c09af46d2735965d24da61f4f8b3b7d8b
• Download URL:
  https://stacks.cdc.gov/view/cdc/191341/cdc_191341_DS1.pdf
• File Type:
  [PDF - 164.72 KB ]