Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1998-4-16
pubmed:abstractText
1. The relaxant actions of acetylcholine and A23187 were examined in the rabbit central ear artery at different intervals following exposure to different doses of radiation with a cobalt60 unit. The artery was irradiated with a dose of 10 Gy, 20 Gy and 45 Gy. Radiation caused dose- and time-dependent impairment of the endothelium-dependent relaxations. The impaired endothelium-dependent relaxations occurred as early as 1 week postirradiation and persisted throughout the experimental period (10 weeks). 2. The endothelium-independent response to sodium nitroprusside was well preserved up to 6 weeks after irradiation. The contractile response to noradrenaline was unaltered by irradiation throughout the experimental period, but in contrast to control vessels, an increase in the sensitivity to noradrenaline in the presence of the nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine was not observed in the irradiated vessels. 3. The impaired endothelium-dependent relaxations in the irradiated vessels were not improved by pretreatment with the NOS substrate L-arginine, the cyclo-oxygenase inhibitor indomethacin or the free radical scavengers superoxide dismutase and catalase. 4. Scanning electron microscopy indicated morphologically intact endothelial cells within the first 4 weeks after irradiation. 5. Western blot analysis showed a significant decrease in the expression of endothelial NOS (eNOS) in the irradiated vessels. 6. These data indicate that endothelial cell function is specifically impaired in the irradiated vessels before morphological endothelial cell damage can be detected. This impairment may be related to diminished eNOS expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0007-1188
pubmed:author
pubmed:issnType
Print
pubmed:volume
123
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
653-60
pubmed:dateRevised
2008-11-20
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Functional and morphological damage of endothelium in rabbit ear artery following irradiation with cobalt60.
pubmed:affiliation
Department of Plastic and Reconstructive Surgery, Hokkaido University School of Medicine, Sapporo, Japan.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't