Source:http://linkedlifedata.com/resource/pubmed/id/10336850
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5
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pubmed:dateCreated |
1999-7-7
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pubmed:abstractText |
A Na/Ca exchange current can be elicited in voltage clamped single ventricular myocytes by the abrupt removal of extracellular Na+ by means of a rapid switcher device. We measured this reverse Na/Ca exchange current in isolated mouse ventricular myocytes from wild-type mice, and from transgenic mice with hearts overexpressing the Na/Ca exchanger. In mouse ventricular myocytes, the current was sensitive to nickel, and was eliminated by removal of intracellular Na+. It was not influenced by 3 m m ouabain, and thus not contaminated by Na pump currents. The magnitude of the current reached a plateau within 10-15 min after obtaining a whole cell patch with the pipettes containing EGTA, to buffer [Ca2+]i and in zero extracellular K+ concentration to completely inhibit the Na pump, and allow equilibration of pipette Na+ with subsarcolemmal [Na+]. The magnitude of the current increased with increases in pipette [Na+]. Comparison of the current magnitudes in wild-type and transgenic myocytes showed a 2.5 and 2.7 fold increase in the current in transgenic myocytes at pipette [Na+] of 10 and 20 m m. The magnitude of this increase in Na/Ca exchanger currents in single transgenic myocytes compares well with the reported 2.5 fold increase in Na+-dependent 45Ca2+ uptake measured in ventricular sarcolemmal vesicles obtained from transgenic animals. With this approach, we found variation in exchanger current densities in different species, with values for mouse>rat>rabbit>dog>human. This technique should also be useful in quantifying changes in Na/Ca exchanger current density as a consequence of pathologic processes, and exposure to drugs.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
May
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pubmed:issn |
0022-2828
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pubmed:author | |
pubmed:copyrightInfo |
Copyright 1999 Academic Press.
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pubmed:issnType |
Print
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pubmed:volume |
31
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1125-35
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:10336850-Animals,
pubmed-meshheading:10336850-Dogs,
pubmed-meshheading:10336850-Heart Ventricles,
pubmed-meshheading:10336850-Humans,
pubmed-meshheading:10336850-Mice,
pubmed-meshheading:10336850-Mice, Transgenic,
pubmed-meshheading:10336850-Rabbits,
pubmed-meshheading:10336850-Rats,
pubmed-meshheading:10336850-Reproducibility of Results,
pubmed-meshheading:10336850-Sodium-Calcium Exchanger,
pubmed-meshheading:10336850-Species Specificity,
pubmed-meshheading:10336850-Ventricular Function
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pubmed:year |
1999
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pubmed:articleTitle |
Quantitation of Na/Ca exchanger function in single ventricular myocytes.
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pubmed:affiliation |
Division of Cardiology, University of Utah Health Sciences Center, Salt Lake City, Utah 84132, USA.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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