Linked Life Data

2852055

Source:http://linkedlifedata.com/resource/pubmed/id/2852055

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1989-4-4
pubmed:abstractText
The electrophysiological effects of three class I antiarrhythmic drugs, lignocaine, disopyramide, and penticainide, were compared in sheep cardiac Purkinje fibres. Action potential duration was shortened with all three drugs, the effect being small with disopyramide, moderate with penticainide, and greatest with lignocaine. Slowing down of the early phase of repolarisation was greatest with disopyramide, smaller with penticainide, and did not occur with lignocaine. Automaticity recorded in low potassium media was unaltered (disopyramide), depressed (penticainide), or stopped (lignocaine). Ionic currents were recorded in short fibres using the two microelectrode voltage clamp technique. The tetrodotoxin sensitive slow component of the sodium current was suppressed (lignocaine) or reduced (penticainide and disopyramide) and the instantaneous background potassium current slightly reduced (disopyramide more than penticainide), unaffected, or slightly increased (lignocaine). The three drugs depressed moderately and similarly the slow inward calcium current. The amplitude of the 4-aminopyridine sensitive transient outward potassium current was almost unaffected (lignocaine) or appreciably depressed (disopyramide more than penticainide). The pacemaker current was reduced greatly by lignocaine, moderately by penticainide, and slightly by disopyramide. Changes in ionic currents may explain the effects of the three drugs on action potential plateau and automaticity of sheep Purkinje fibres. It is concluded that the pronounced differences observed in the effects of these three class I antiarrhythmic drugs on pacemaker depolarisation and on initial repolarisation may justify a more discriminative subdivision of class I antiarrhythmic drugs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0008-6363
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
375-84
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Comparative effects of three class I antiarrhythmic drugs on plateau and pacemaker currents of sheep cardiac Purkinje fibres.
pubmed:affiliation
Laboratory of Comparative Physiology, University of Paris, Orsay, France.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't