Linked Life Data

9815079

Source:http://linkedlifedata.com/resource/pubmed/id/9815079

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 2
pubmed:dateCreated
1998-12-10
pubmed:abstractText
The ultrarapid delayed rectifier current (IK,ur) plays a significant role in human atrial repolarization and is generally believed to show little rate dependence because of slow and partial inactivation. This study was designed to evaluate in detail the properties and consequences of IK,ur inactivation in isolated human atrial myocytes. IK,ur inactivated with a biexponential time course and a half-inactivation voltage of -7.5 +/- 0.6 mV (mean +/- SE), with complete inactivation during 50-s pulses to voltages positive to +10 mV (37 degreesC). Recovery from inactivation proceeded slowly, with time constants of 0.42 +/- 0.06 and 7.9 +/- 0.9 s at -80 mV (37 degreesC). Substantial frequency dependence was observed at 37 degreesC over a clinically relevant range of frequencies. Inactivation was faster and occurred at more positive voltages at 37 degreesC compared with room temperature. The voltage and time dependencies of Kv1.5 inactivation were studied in Xenopus oocytes to avoid overlapping currents and strongly resembled those of IK,ur in native myocytes. We conclude that, while IK,ur inactivation is slow, it is extensive, and slow recovery from inactivation confers important frequency dependence with significant consequences for understanding the role of IK,ur in human atrial repolarization.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1717-25
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Ultrarapid delayed rectifier current inactivation in human atrial myocytes: properties and consequences.
pubmed:affiliation
Department of Medicine, Montreal Heart Institute, Montreal, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't