Linked Life Data

8860070

Source:http://linkedlifedata.com/resource/pubmed/id/8860070

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-2-19
pubmed:abstractText
Increased numbers of eosinophils and increased concentrations of plasma proteins have been found in the airways of patients with mild asthma. We used an intact guinea pig trachea model to investigate the role of eosinophil peroxidase (EPO) in altering the function of the airway epithelial barrier. EPO in the presence of hydrogen peroxide (H(2)O(2)) and bromide (Br(-)) catalyzes the production of hypobromous acid (HOBr), which is felt to have a toxic effect on airway epithelial cells. An intact guinea pig trachea was mounted on an apparatus in a way that would allow the tracheal epithelium to be exposed to different solutions. Following these exposures, a test solution containing (14)C-sucrose (S), (3)H-inulin (I), and FITC-dextran-20 (D) was placed in the tracheal lumen and positioned in the center of the segment for 90 minutes. Flux of these molecules across the epithelial barrier into a bath was measured, and the permeability (P) was calculated for each molecule to quantify epithelial barrier function. Light and electron micrographic studies were performed to assess cellular damage. We found that there was a dose response to EPO (in the presence of fixed amounts of H(2)(O)(2) and Br(-)). EPO at 7.3 x 10(-7) M caused no increase in P over controls (Ringer's solution alone) for S, I, or D (P> 0.05), whereas EPO at 2.7 x 10(-6) M caused a significant increase in P over controls (P = 0.008) for all test molecules. Light and electron micrographs of the latter tracheas showed no evidence of microscopic changes despite the increased P. Further testing verified that the increase in permeability was caused by the EPO catalyzed reaction and not the individual substrates themselves, and that the reaction was inhibited by a peroxidase inhibitor. We conclude that EPO can alter the barrier function of the airway epithelium before gross cellular damage becomes visible. We hypothesize that changes in the tight junctions are responsible for the alteration in the barrier function of the airway epithelium and that this may play an important role in the pathophysiology of mild asthma.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
8755-6863
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
159-66
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Effect of eosinophil peroxidase on airway epithelial permeability in the guinea pig.
pubmed:affiliation
Department of Pediatrics, University of Minnesota, Minneapolis, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't