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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5 Pt 1
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pubmed:dateCreated |
1997-12-17
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pubmed:abstractText |
Phospholamban (PLB) ablation is associated with enhanced sarcoplasmic reticulum (SR) Ca2+ uptake and attenuation of the cardiac contractile responses to beta-adrenergic agonists. In the present study, we compared the effects of isoproterenol (Iso) on the Ca2+ currents (ICa) of ventricular myocytes isolated from wild-type (WT) and PLB knockout (PLB-KO) mice. Current density and voltage dependence of ICa were similar between WT and PLB-KO cells. However, ICa recorded from PLB-KO myocytes had significantly faster decay kinetics. Iso increased ICa amplitude in both groups in a dose-dependent manner (50% effective concentration, 57.1 nM). Iso did not alter the rate of ICa inactivation in WT cells but significantly prolonged the rate of inactivation in PLB-KO cells. When Ba2+ was used as the charge carrier, Iso slowed the decay of the current in both WT and PLB-KO cells. Depletion of SR Ca2+ by ryanodine also slowed the rate of inactivation of ICa, and subsequent application of Iso further reduced the inactivation rate of both groups. These results suggest that enhanced Ca2+ release from the SR offsets the slowing effects of beta-adrenergic receptor stimulation on the rate of inactivation of ICa.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adenosine Triphosphatases,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium-Binding Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Isoproterenol,
http://linkedlifedata.com/resource/pubmed/chemical/Ryanodine,
http://linkedlifedata.com/resource/pubmed/chemical/phospholamban
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pubmed:status |
MEDLINE
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pubmed:month |
Nov
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pubmed:issn |
0002-9513
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
273
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
C1666-72
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:9374653-Adenosine Triphosphatases,
pubmed-meshheading:9374653-Animals,
pubmed-meshheading:9374653-Calcium,
pubmed-meshheading:9374653-Calcium Channels,
pubmed-meshheading:9374653-Calcium-Binding Proteins,
pubmed-meshheading:9374653-Cells, Cultured,
pubmed-meshheading:9374653-Heart,
pubmed-meshheading:9374653-Heart Ventricles,
pubmed-meshheading:9374653-Isoproterenol,
pubmed-meshheading:9374653-Kinetics,
pubmed-meshheading:9374653-Membrane Potentials,
pubmed-meshheading:9374653-Mice,
pubmed-meshheading:9374653-Mice, Knockout,
pubmed-meshheading:9374653-Mice, Transgenic,
pubmed-meshheading:9374653-Myocardial Contraction,
pubmed-meshheading:9374653-Ryanodine,
pubmed-meshheading:9374653-Sarcoplasmic Reticulum
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pubmed:year |
1997
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pubmed:articleTitle |
Modulation of cardiac Ca2+ channels by isoproterenol studied in transgenic mice with altered SR Ca2+ content.
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pubmed:affiliation |
Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Ohio 45267, USA.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, U.S. Gov't, Non-P.H.S.
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