Effects of Lipopolysaccharide on Tracheal Epithelial Bioelectric Responses to Serosally- and Mucosally-Applied Methacholine

Details

• Personal Author:
  Fedan, Jeffery S. ; Johnston RA
• Description:
  We examined whether lipopolysaccharide (LPS) affects transepithelial potential difference V of guinea-pig tracheal epithelium and bioelectric responses to serosally- and mucosally-applied methacholine (MCh). V was measured in vitro using the isolated perfused trachea apparatus, which allows addition of MCh separately to the mucosal or serosal surface. Eighteen hours after LPS (4 mg/kg, Lp.) basal V was increased (saline: -14.9+/- 1.6 mV; LPS: -27.7+/-2.5 mV; p<0.05). In both saline and LPS-treated animals, the dose-response curves for serosally-added MCh were biphasic (hyperpolarization at [MCh] < 10(-6) M; depolarization at [MCh] > 10(-6) M). After LPS-treatment the ECso and maximum response for hyperpolarization were decreased and increased, respectively (p < 0.05), but the EC50 and maximum response for depolarization were not changed. Mucosal MCh was less potent and dose-response curves also were biphasic (hyperpolarization < 10(-3) M; depolarization > 10(-3) M). The maximum hyperpolarization was increased (p<0.05) after LPS-treatment; the depolarization was unaffected. The results suggest that high and low affinity muscarinic receptors initiate changes in V. The mechanism involved in high affinity receptor-induced hyperpolarization is potentiated after LPS-treatment. [Description provided by NIOSH]
• Subjects:
  Animals Laboratories Nose Occupational Health Safety Sense Organs
• Keywords:
  Animal-studies Bioelectric-effects In-vitro-studies Laboratory-animals Nasal-cavity
• ISSN:
  1073-449X
• Document Type:
  Text
• Genre:
  Abstract or Summary ; Proceedings
• 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
• Volume:
  159
• Issue:
  3
• NIOSHTIC Number:
  nn:20030634
• Citation:
  Am J Respir Crit Care Med 1999 Mar; 159(3)(Suppl):A294
• Federal Fiscal Year:
  1999
• Peer Reviewed:
  False
• Source Full Name:
  American Journal of Respiratory and Critical Care Medicine
• Supplement:
  Suppl
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:53cc0d21e05e0bc8017aa2eb8bea466f8412fcfcbae6bc77ef32fafb2f3c3e2c541658f6a20d08e73d236037d83a5333c17bbd81d118c0ab25cc4ee51aea71ed
• Download URL:
  https://stacks.cdc.gov/view/cdc/191177/cdc_191177_DS1.pdf
• File Type:
  [PDF - 1.11 MB ]