Linked Life Data

6195461

Source:http://linkedlifedata.com/resource/pubmed/id/6195461

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1983-12-20
pubmed:abstractText
We studied the effects of yohimbine, and alpha-adrenoceptor blocker with selectivity for the alpha 2-subtype, on myocardial norepinephrine (NE) overflow, regional myocardial blood flow (RMBF), and patterns of epicardial conduction abnormalities during occlusion of the proximal left anterior coronary artery in an open-chest anaesthetised dog model. With a 12-min period of coronary occlusion (n = 9), spontaneous overflow of NE into ischaemic venous effluent was not observed either before or after yohimbine (1 mg/kg i.v.), but the drug significantly potentiated the enhanced NE overflow during supramaximal stimulation of the left stellate ganglion at low (1 Hz) and high (10 Hz) frequency [peak NE 4.3 +/- 0.4 pmol/ml control; 11.8 +/- 5.4 pmol/ml yohimbine (p less than 0.005)] with a delayed return towards prestimulation levels. Myocardial NE overflow on coronary reperfusion was also enhanced. Yohimbine increased arterial epinephrine two- to threefold but did not substantially alter myocardial lactate overflow during coronary occlusion. RMBF was reduced 24 and 36% to ischaemic endocardium and epicardium, respectively (p less than 0.01, compared with control occlusion). This contrasted with a 9 and 6% decrease in flow to the respective nonischaemic areas (p = NS, compared with control occlusion. Spontaneous ventricular fibrillation and the area and magnitude of epicardial conduction abnormalities in the ischaemic myocardium were both increased compared with the control occlusion. Thus, alpha-blockers with selectivity for the alpha 2-adrenoceptor may be detrimental to acutely ischaemic myocardium, presumably through increased local catecholamine release at the nerve terminal.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0160-2446
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
752-9
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:articleTitle
Alpha-adrenoceptor control of norepinephrine release from acutely ischaemic myocardium: effects of blood flow, arrhythmias, and regional conduction delay.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't