Linked Life Data

8460719

Source:http://linkedlifedata.com/resource/pubmed/id/8460719

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3 Pt 1
pubmed:dateCreated
1993-4-29
pubmed:abstractText
The effects of H2O2 on active ion transport and resistance to passive solute flow were studied utilizing rat alveolar epithelial cell monolayers cultured on permeable supports. Type II alveolar epithelial cells were plated onto tissue culture-treated polycarbonate membrane filters. The resulting confluent monolayers on days 3 and 4 were mounted in a modified Ussing chamber and bathed on both sides with N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid-buffered Ringer solution. These monolayers have a high transepithelial resistance (> 2,000 omega.cm2) and actively transport Na+ from apical fluid. H2O2 (0-100 mM) was then delivered to either apical or basolateral fluid. The changes in short-circuit current (Isc) and monolayer resistance (R) in response to the exogenous hydroperoxide were measured. To determine the degree of cellular catalase participation in protection against H2O2 injury to the barrier, experiments were repeated in the presence of 20 mM aminotriazole (ATAZ; an inhibitor of catalase) in the same bathing fluid as the hydroperoxide. Results indicated that H2O2 decreased Isc and R gradually in a dose-dependent manner. The effective concentration of apical H2O2 at which Isc (or R) was decreased by 50% at 1 h (ED50) was approximately 4 mM. However, basolateral H2O2 exposure led to ED50 for Isc (and R) of approximately 0.04 mM. Inhibition of cellular catalase yielded ED50 for Isc (and R) of approximately 0.4 mM when H2O2 was given apically, while ED50 for basolateral exposure to H2O2 did not change in the presence of ATAZ. The rate of H2O2 consumption in apical and basolateral bathing fluids was the same, while cellular catalase activity rose gradually with time in culture.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
264
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
L308-15
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Asymmetric effects of H2O2 on alveolar epithelial barrier properties.
pubmed:affiliation
Department of Medicine, School of Medicine, University of Southern California, Los Angeles 90033.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't