Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4 Pt 1
pubmed:dateCreated
1992-11-25
pubmed:abstractText
Lung cytochrome P-450 has been suggested to play a role in hypoxic pulmonary vasoconstriction. We reexamined this hypothesis using specific suicide substrate inhibitors of cytochrome P-450, 1-aminobenzotriazole (1-ABT), and chloramphenicol. In isolated, blood-perfused rat lungs, 1-ABT (0.5 mg/ml) and chloramphenicol (1 mg/ml) inhibited lung microsomal cytochrome P-450 (ethoxycoumarin O-deethylase) activity to 24 and 44% of control, respectively, and blunted hypoxia and angiotensin II-induced vasoconstriction. The depression of vascular contraction by 1-ABT was not due to an effect on calcium channels, since similar concentrations of 1-ABT had no inhibitory activity on electrical field-stimulated contractile response in rabbit papillary muscle strips. However, when 1-ABT was washed out of the lung after preincubation, the vascular reactivity to hypoxia and angiotensin II was restored despite persistent depression of lung cytochrome P-450 activity to 26% of control values. In isolated rat aortic and pulmonary arterial rings, addition of 1-ABT or metyrapone to the organ bath acutely reversed norepinephrine-induced contraction but preincubation with 1-ABT, metyrapone, or chloramphenicol had no effect on subsequent norepinephrine contractions. We conclude that 1-ABT inhibited lung vascular reactivity by a mechanism independent of cytochrome P-450 inhibition or calcium channel blockade and that an intact lung cytochrome P-450 system is not required for hypoxic pulmonary vasoconstriction in rat lungs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
263
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
L446-53
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Intact lung cytochrome P-450 is not required for hypoxic pulmonary vasoconstriction.
pubmed:affiliation
Cardiovascular Pulmonary Research Laboratory, Webb-Waring Lung Institute, University of Colorado Health Sciences Center, Denver 80262.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't