Linked Life Data

2841874

Source:http://linkedlifedata.com/resource/pubmed/id/2841874

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2 Pt 2
pubmed:dateCreated
1988-9-14
pubmed:abstractText
To test the hypothesis that alpha 2-adrenoceptor activity exerts a dual control of coronary blood flow, i.e., vasoconstriction and augmentation of the vasodilatory effect of adenosine, four doses of adenosine were infused into left anterior descending coronary artery before and during alpha 2-adrenoceptor stimulation or attenuation in anesthetized open-chest dogs. During a moderate alpha 2-adrenoceptor attenuation (yohimbine or rauwolscine, ic), which did not alter coronary blood flow (CBF) at the base-line condition, the hyperemic response of CBF to infused adenosine was markedly reduced, whereas during the potent attenuation both base-line CBF and adenosine-induced hyperemic CBF were significantly increased. Inversely, the moderate alpha 2-stimulation (0.03 microgram.kg-1.min-1 norepinephrine with prazosin, ic, or 0.04 microgram.kg-1.min-1 clonidine ic, under propranolol pretreatment) augmented the adenosine-induced coronary vasodilation, but the potent alpha 2-stimulation (0.3 microgram.kg-1.min-1 norepinephrine with prazosin ic, or 0.3 microgram.kg-1.min-1 clonidine ic) reduced both base-line CBF hyperemic CBF. In contrast, alpha 2-adrenoceptor activity did not affect papaverine-induced coronary vasodilation. Moreover, the reactive hyperemic flow after a brief coronary occlusion was reduced significantly during the moderate alpha 2-adrenergic attenuation, but it was augmented during the potent one. These results indicate that the moderate activation of the alpha 2-adrenoceptor augments the hyperemic response of CBF to both exogenous and endogenous adenosine, whereas the potent alpha 2-activation may mask this vasodilatory effect through the coronary vasoconstrictive effect.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
255
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H250-60
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Alpha 2-adrenoceptor activity exerts dual control of coronary blood flow in canine coronary artery.
pubmed:affiliation
First Department of Medicine, Osaka University School of Medicine, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't