Linked Life Data

2239663

Source:http://linkedlifedata.com/resource/pubmed/id/2239663

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1990-12-4
pubmed:abstractText
The cellular electrophysiologic effects of exogenous phosphocreatine (PCr) were analyzed to ascertain its purported antiarrhythmic properties during myocardial ischemia and reperfusion. Transmembrane potentials were recorded from isolated guinea pig papillary muscles and Purkinje fibers studied in vitro. Under control, normoxic conditions, 10 mmol/L PCr significantly increased the action potential duration (measured at 90% of repolarization) in ventricular muscle by 14.6 +/- 3.3 msec and the effective refractory period by 11.5 +/- 3.8 msec (both p less than 0.01). Under ischemic-like conditions (hypoxia, lactic acidosis, elevated [K+]o, zero substrate) PCr had no effect. Phosphocreatinine, a related compound that is not a direct substrate in the creatine kinase reaction, acted similarly to PCr suggesting that alterations induced by PCr did not involve a change in the energy state of cells. However, PCr reduced free [Ca2+]o by nearly 20%, and its electrical effects under normoxic conditions could be largely reversed by a concomitant 20% increase in [Ca2+]o. In Purkinje fibers superfused with low [K+]o-Tyrode's solution to elicit conditions of Ca2+ overload, delayed afterdepolarizations and triggered responses were reversibly inhibited by PCr. These data suggest that the antiarrhythmic effects of PCr in situ may involve prolongation of the effective refractory period in nonischemic tissue or attenuation of membrane changes elicited by Ca2+ overload in ischemic cells. The mechanism by which PCr produces these effects may be related in part to changes in extracellular Ca2+ composition.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0002-8703
pubmed:author
pubmed:issnType
Print
pubmed:volume
120
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1111-9
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Electrophysiologic effects of exogenous phosphocreatine in cardiac tissue: potential antiarrhythmic actions.
pubmed:affiliation
Institute of Experimental Cardiology, USSR Cardiology Research Center, Moscow.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't