Linked Life Data

2443266

Source:http://linkedlifedata.com/resource/pubmed/id/2443266

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1987-11-2
pubmed:abstractText
We assessed the effects of type I antiarrhythmic drugs on the binding of ligands to receptors on voltage-sensitive sodium channels of rat cardiac myocytes. The radioligand was [3H]batrachotoxinin A 20 alpha-benzoate ([3H]BTXB), a toxin that binds to the sodium channel. The 8 drugs tested inhibited [3H]BTXB binding in a dose-dependent fashion with IC50 values from 1.34 microM for O-demethylencainide to 811 microM for procainamide. A log-log plot of IC50 versus mean therapeutic serum concentration yielded a regression line with slope of 1.17 and r of 0.95. Scatchard analysis of [3H]BTXB binding showed that lidocaine reduced the maximal binding without altering the KD for [3H]BTXB binding, indicating allosteric inhibition. The inhibition by lidocaine of [3H]BTXB binding was reversible within 30 minutes when the samples were diluted from 390 to 39 microM lidocaine. In other studies, the stereoisomers of tocainide were shown to have a threefold to fourfold difference in IC50 for inhibition of [3H]BTXB binding. The binding of antiarrhythmic drugs to this site is saturable, reversible, and stereospecific and occurs at pharmacologically relevant concentrations with similar rank order of potency in vivo and in vitro. This suggests that binding at this site relates to pharmacologic activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0009-7330
pubmed:author
pubmed:issnType
Print
pubmed:volume
61
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
492-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
A receptor for type I antiarrhythmic drugs associated with rat cardiac sodium channels.
pubmed:affiliation
Department of Medicine, University of Calgary, Faculty of Medicine, Alberta, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't