Source:http://linkedlifedata.com/resource/pubmed/id/11299215
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5
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pubmed:dateCreated |
2001-4-12
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pubmed:abstractText |
In isovolumic blood-perfused dog hearts, left ventricular developed pressure (DP) was recorded while a sudden ventricular dilation was promoted at three heart rate (HR) levels: low (L: 52 +/- 1.7 beats/min), intermediate (M: 82 +/- 2.2 beats/min), and high (H: 117 +/- 3.5 beats/min). DP increased instantaneously with chamber expansion (Delta(1)DP), and another continuous increase occurred for several minutes (Delta(2)DP). HR elevation did not alter Delta(1)DP (32.8 +/- 1.6, 33.6 +/- 1.5, and 34.3 +/- 1.2 mmHg for L, M, and H, respectively), even though it intensified Delta(2)DP (17.3 +/- 0.9, 20.7 +/- 1.0, and 26.8 +/- 1.2 mmHg for L, M, and H, respectively), meaning that the treppe phenomenon enhances the length dependence of the contraction component related to changes in intracellular Ca(2+) concentration. Frequency increments reduced the half time of the slow response (82 +/- 3.6, 67 +/- 2.6, and 53 +/- 2.0 s for L, M, and H, respectively), while the number of beats included in half time increased (72 +/- 2.9, 95 +/- 2.9, and 111 +/- 3.2 beats for L, M, and H, respectively). HR modulation of the slow response suggests that L-type Ca(2+) channel currents and/or the Na(+)/Ca(2+) exchanger plays a relevant role in the stretch-triggered Ca(2+) gain when HR increases in the canine heart.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:status |
MEDLINE
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pubmed:month |
May
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pubmed:issn |
0363-6135
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
280
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
H2136-43
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pubmed:dateRevised |
2010-11-18
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pubmed:meshHeading |
pubmed-meshheading:11299215-Animals,
pubmed-meshheading:11299215-Balloon Dilation,
pubmed-meshheading:11299215-Dogs,
pubmed-meshheading:11299215-Heart Rate,
pubmed-meshheading:11299215-Male,
pubmed-meshheading:11299215-Myocardial Contraction,
pubmed-meshheading:11299215-Reaction Time,
pubmed-meshheading:11299215-Ventricular Function, Left
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pubmed:year |
2001
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pubmed:articleTitle |
Heart rate modulates the slow enhancement of contraction due to sudden left ventricular dilation.
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pubmed:affiliation |
Department of Physiology, Universidade Federal de São Paulo, Escola Paulista de Medicina, CEP 04023-900 São Paulo, Brazil. tucci@fcr.emp.br
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
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