Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-4-6
pubmed:abstractText
It has been postulated that changes in the availability of partially reduced O2 species, such as O2 radicals, could serve as a link between PO2 in the alveolus and pulmonary vascular tone (Herz 11: 127-141, 1986). To assess this hypothesis, the hemodynamic effects of acute changes in the balance between the production of O2 radicals and availability of antioxidant enzymes were studied in the isolated perfused rat lung. Intravascular generation of O2 radicals, by administration of xanthine-xanthine oxidase, decreased the pulmonary vascular pressor response to alveolar hypoxia (-55 +/- 5%) and angiotensin II (-58 +/- 10%, P less than 0.01 for each) in isolated perfused rat lungs without increasing the lung wet-to-dry weight ratio. Decreases in pulmonary vascular reactivity were inhibited by pretreatment of the lung with desferrioxamine or a mixture of catalase and superoxide dismutase. Catalase and superoxide dismutase preserved the hypoxic pressor response whether given in liposomes or in dissolved form. Superoxide dismutase administered free in solution, or combined with catalase in liposomes, increased the normoxic pulmonary arterial pressure and enhanced vascular reactivity to angiotensin II and hypoxia. Lungs treated with antioxidant enzymes in liposomes had 50% higher lung catalase levels than control lungs (P less than 0.05). These findings demonstrate that exogenous partially reduced O2 species can decrease pulmonary vascular reactivity and suggest that endogenous radicals, superoxide radical in particular, might be important in modulating pulmonary vascular tone.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
66
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
102-11
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Oxygen radicals and antioxidant enzymes alter pulmonary vascular reactivity in the rat lung.
pubmed:affiliation
Department of Medicine, Veterans Administration Medical Center, Minneapolis, Minnesota 55455.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't