Linked Life Data

7771531

Source:http://linkedlifedata.com/resource/pubmed/id/7771531

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 2
pubmed:dateCreated
1995-7-6
pubmed:abstractText
Gadolinium-sensitive stretch-activated channels have been implicated in the process of mechanotransduction signaling of ventricular myocardium. Such channels nonspecifically transport Na+ and Ca2+ in the inward direction. We tested the hypothesis that Na+ and Ca2+ influx are important in the genesis of stretch-induced arrhythmias (SIAs) in an isolated, blood-perfused canine ventricle. To elicit SIAs, left ventricular volume was transiently increased in early diastole using a computerized servo-pump system. Monophasic action potential recordings revealed stretch-induced depolarizations (SIDs) that preceded the arrhythmias. In five ventricles, raising the perfusate Ca2+ concentration from 1 to 3 mM increased ventricular sensitivity to SIAs, manifested by a decrease in the volume change required to precipitate an arrhythmia 50% of the time (delta V50) from 19.5 +/- 2.7 to 15.2 +/- 1.9 ml (P < 0.05). When the perfusate Na+ concentration was decreased from 150 to 90 mM in seven ventricles, delta V50 greatly increased (31.1 +/- 14.4 vs. 17.7 +/- 5.3 ml, P < 0.05), and SID amplitude decreased by 47% (P = 0.002). The suppression of SIAs with low extracellular Na+ is unlikely to be mediated by voltage-gated Na+ channels because lidocaine (5 mg/dl) did not alter SID amplitude. Thus the transsarcolemmal Na+ gradient (and probably that of Ca2+) modulates the amplitude of SIDs, which, in turn, initiate SIAs. These data provide initial evidence that Na+ and Ca2+ help mediate the mechanotransduction processes that underly the genesis of SIAs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
268
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1803-13
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Calcium- and sodium-dependent modulation of stretch-induced arrhythmias in isolated canine ventricles.
pubmed:affiliation
Division of Cardiology, Vanderbilt University Medical School, Nashville, Tennessee 37232, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.