Linked Life Data

2913282

Source:http://linkedlifedata.com/resource/pubmed/id/2913282

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-3-3
pubmed:abstractText
Although the Ca++ channel blockers can reduce early ischemic ventricular arrhythmias, the mechanisms are unclarified. The antiarrhythmic action of Ca++ antagonists may either be due to vasodilation and negative chronotropism or to trans-sarcolemmal Ca++ influx inhibition. In these studies we investigated the possible individual and additive effects of coronary flow, heart rate and Ca++ antagonism on ventricular arrythmia development in isolated, paced, globally underperfused guinea pig hearts. When the coronary flow during ischemia was raised from 5 to 7% of control and/or the stimulation frequency was decreased from 6 to 4 Hz, ATP and creatine phosphate levels were conserved and intraventricular conduction slowing leading to ventricular tachycardia (VT) was delayed. In contrast, when the coronary flow and pacing rates were fixed at 7% and 6 Hz and diltiazem (10(-6) M) was included in the perfusion medium, there was no effect on tissue high-energy phosphate depletion and development of VT. Even when the breakdown of ATP and the onset of VT were accelerated by isoprenaline (10(-6) M), diltiazem was not antiarrhythmic at this flow rate. Only when the coronary flow was reduced to 5% of control, in the absence and presence of isoprenaline, did diltiazem delay ventricular arrhythmias through a mechanism that was independent of changes in coronary flow and heart rate.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
248
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
372-7
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Effects of coronary flow, pacing rate, isoprenaline and diltiazem on ischemic ventricular arrhythmias in guinea pig hearts.
pubmed:affiliation
Ischemic Heart Disease Research Unit, University of Cape Town Medical School, Observatory, South Africa.
pubmed:publicationType
Journal Article, In Vitro