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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
1982-12-3
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pubmed:abstractText |
To determine whether monoalyers of cultured chick embryo ventricular cells would show tachyphylaxis to chronotropic and inotropic effects of a beta adrenergic agonist, spontaneously contracting monolayers of primary cell cultures were studied using a phase-contrast microscope-video motion detector system that permitted quantitation of the chronotropic and inotropic state. The monoalyers were chronotropically unresponsive to isoproterenol between 10(-9) to 10(-6) M and chronotropically unresponsive to a 6-fold increase in perfusate calcium concentration. However, the cells were very inotropically responsive to calcium and to isoproterenol. Expressing the isoproterenol inotropic response as a percentage of response to 3.6 mM Ca, the response to 10(-6) M isoproterenol was 79 +/- 4% of the Ca response and the EC50 for isoproterenol was 3 x 10(-9) M. The monolayers rapidly developed dose-dependent desensitization to the inotropic effect of isoproterenol; after a 30-min exposure to 1 x 10(-6) M isoproterenol, the inotropic response was 40 +/- 5% of the initial response; desensitization was long-lasting and could be prevented by propranolol. Response to calcium remained unchanged after exposure to 10(-6) M isoproterenol. Thus, the cultured cell preparation shows rapid, sustained, beta receptor specific desensitization to the inotropic effects of a catecholamine.
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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 |
Oct
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pubmed:issn |
0022-3565
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
223
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
60-7
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:6288921-Animals,
pubmed-meshheading:6288921-Calcium,
pubmed-meshheading:6288921-Cells, Cultured,
pubmed-meshheading:6288921-Chick Embryo,
pubmed-meshheading:6288921-Culture Media,
pubmed-meshheading:6288921-Heart Rate,
pubmed-meshheading:6288921-Heart Ventricles,
pubmed-meshheading:6288921-Isoproterenol,
pubmed-meshheading:6288921-Myocardial Contraction,
pubmed-meshheading:6288921-Receptors, Adrenergic, beta
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pubmed:year |
1982
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pubmed:articleTitle |
Desensitization to the inotropic effect of isoproterenol in cultured ventricular cells.
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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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