Responses of Guinea-Pig Isolated, Perfused Trachea (IPT) to Luminally-Applied Hypertonic and Isotonic Osmolyte Solutions

Details

• Personal Author:
  Fedan, Jeffery S. ; Johnston RA ; Rengasamy A
• Description:
  Delivery of modified Krebs-Henseleit solution (MKHS) of raised osmolarity (added NaCl or KCl) to the lumen of methacholine (MCh)-contracted IPT results in a relaxation response of the airway smooth muscle that is mediated by epithelium-derived relaxing factor (EpDRF). We compared the effects of luminally-applied solutions containing organic osmolytes added to MKHS to raise osmolarity (hypertonic solutions) or isotonic solutions to the osmolytes. As has been observed previously with NaCl and KCl, solutions made hypertonic with urea, mannitol, N-methyl-D-glucamine-Cl (NMDG) and Na-gluconate (Glu) elicited osmolar concentration - dependent relaxations of MCh (3 x 10^-7 M) - contracted IPT when applied to the mucosal surface. To determine if relaxation responses caused by hypertonic solutions involved airway epithelial cell shrinkage, IPT were challenged intraluminally with isotonic mannitol, urea, NMDG, Glu or NaCl. Generally, mannitol, NMDG, and Glu evoked complex responses containing contraction and relaxation. Urea caused contraction or relaxation in different tracheas. NaCl was primarily relaxant. These findings suggest that EpDRF release in response to hypertonicity does not result from cell shrinkage per se, but may be due to altered ion fluxes. [Description provided by NIOSH]
• Subjects:
  Animals Laboratories Lung Diseases Musculoskeletal System Occupational Health Respiratory System Respiratory Tract Diseases Safety
• Keywords:
  Airway Obstruction Airway Resistance Animal Studies Laboratory Animals Muscles Pulmonary System Disorders Respiratory System Disorders
• ISSN:
  0892-6638
• Document Type:
  Text
• Genre:
  Abstract or Summary ; Proceedings
• Place as Subject:
  California ; OSHA Region 3 ; OSHA Region 9 ; 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:
  14
• Issue:
  4
• NIOSHTIC Number:
  nn:20020925
• Citation:
  FASEB J 2000 Apr; 14(4):A602
• Federal Fiscal Year:
  2000
• Peer Reviewed:
  False
• Source Full Name:
  The FASEB Journal
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:56466dce76e6b0b3c55626eb50859c02211a60753243a7149b69ee928204eeba59b68525d652596b0b4e8bb6d6a555590a98ee5d16b4430147ee866836b624e2
• Download URL:
  https://stacks.cdc.gov/view/cdc/198554/cdc_198554_DS1.pdf
• File Type:
  [PDF - 467.32 KB ]