Linked Life Data

10420082

Source:http://linkedlifedata.com/resource/pubmed/id/10420082

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-8-24
pubmed:abstractText
The slow delayed rectifier potassium current (I(Ks)) is unique in its slow activation and deactivation kinetics. It is important during cardiac repolarization, especially when the heart rate is fast. We compared the effects of quinidine, procainamide, sotalol, and amiodarone on I(Ks) and correlated the findings with the clinical reverse use-dependent effects of potassium channel blockers. Human minK RNA was obtained by reverse transcription-polymerase chain reaction using explanted human heart. The RNA was injected into Xenopus oocytes for heterologous expression of I(Ks). A two-electrode voltage clamp technique was performed to investigate the I(Ks). We demonstrated that quinidine, sotalol and procainamide had no effects on I(Ks) up to a concentration of 300 microM while amiodarone inhibited I(Ks) in a concentration-dependent manner starting from 10 microM. The inhibition by amiodarone was state-dependent with gradual unblocking after depolarization. The degree of inhibition was 53% immediately after depolarization and 19% at the end of a 5-second depolarization. I(Ks) is 30 times more sensitive to amiodarone than to quinidine, sotalol, and procainamide. Quinidine, sotalol and procainamide have reverse use-dependent effects while amiodarone does not. This is compatible with the hypothesis that no inhibition of I(Ks) at clinical concentrations contributes to the clinical reverse use-dependent effects.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1021-7770
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
251-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
Sensitivity of the slow component of the delayed rectifier potassium current (IKs) to potassium channel blockers: implications for clinical reverse use-dependent effects.
pubmed:affiliation
Institute of Pharmacology, National Taiwan University, National Taiwan University Hospital, Taipei, Taiwan, ROC.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't