Linked Life Data

9831915

Source:http://linkedlifedata.com/resource/pubmed/id/9831915

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-3-25
pubmed:abstractText
1. In this study we investigated the ability of ascorbate to protect nitric oxide from destruction by superoxide anion. 2. Ascorbate produced concentration-dependent relaxation of rings of rat aorta, comprising two components: the first, seen at 1-300 microM, reached a maximum of 45.3+/-2.8%, and was abolished by endothelial removal or treatment with L-NAME (100 microM), demonstrating involvement of nitric oxide. The second occurred at concentrations of 1 mM and above and was associated with falls in the pH of the bathing fluid. 3. Pretreatment with ascorbate at concentrations up to 3 mM had no effect on the relaxation to acetylcholine (10 nM-10 microM) on endothelium-containing rings or adenosine (0.1 microM-3 mM) on endothelium-denuded rings. 4. An oxidant stress was applied to aortic rings, comprising inhibition of endogenous Cu/Zn superoxide dismutase by diethyldithiocarbamate (0.1 mM) followed by generation of superoxide anion by hypoxanthine (0.1 mM/xanthine oxidase (16 u ml(-1)). This reduced maximal acetylcholine-induced relaxation from 96.7+/-1.3% to 42.4+/-3.5% (P<0.001). Treatment with ascorbate (30 microM-3 mM) reversed this blockade in a concentration-dependent manner. 5. Our findings show that ascorbate has the ability to protect nitric oxide from destruction by superoxide anion. This action is seen with ascorbate at levels normally present in plasma, suggesting that this antioxidant may exert a tonic protective effect on nitric oxide within the vasculature.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0007-1188
pubmed:author
pubmed:issnType
Print
pubmed:volume
125
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
782-6
pubmed:dateRevised
2009-9-29
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Recovery by ascorbate of impaired nitric oxide-dependent relaxation resulting from oxidant stress in rat aorta.
pubmed:affiliation
Clinical Research Initiative, Institute of Biomedical & Life Sciences, University of Glasgow.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't