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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1983-6-23
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pubmed:abstractText |
An analysis of [3H]ouabain binding to electrically stimulated, contracting guinea pig left atria gave the following results. (1) A non-linear Scatchard plot with at least two binding sites: a high-affinity site (KD 1.1 X 10(-6) M) with about 430 receptors/micron2 related to positive inotropy, and a low-affinity site (KD' 2.1 X 10(-4) M) with about 18,000 receptors/micron2, possibly related to (Na+ + K+)ATPase inhibition. A crude left atrial homogenate gave about 530 receptors/micron2. (2) Half-maximal positive inotropic effects occurred at about 4 X 10(-7) M. (3) 86Rb+-uptake was significantly increased at all inotropic ouabain concentrations (10(-7) - 10(-6) M). Toxic concentrations (above 2 X 10(-6) M) inhibited 86Rb+-uptake (half-maximal inhibition at about 5 X 10(-6) M). [3H]Ouabain binding to partly purified guinea pig cardiac cell membranes showed: (a) linear Scatchard plots for (Mg2+, Pi)- and (Na+, ATP, Mg2+)-supported binding (KD 1.18 X 10(-7) M and 1.49 X 10(-7) M, respectively); (b) non-linear Scatchard plots for (Tyrode + ATP)-supported binding (KD 4.7 X 10(-7) M; KD' 6 X 10(-6) M); and (c) half-maximal [3H]ouabain binding occurred at a lower concentration (about 3.2 X 10(-7) M) than half-maximal inhibition of (Na+ + K+)ATPase activity (about 7.2 X 10(-7) M). Thus, we conclude that there may be more than one type of ouabain binding site in guinea pig left atria, and that measurable inhibition of (Na+ + K+)ATPase is not necessarily related to positive inotropy in the guinea pig.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Ouabain,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium Chloride,
http://linkedlifedata.com/resource/pubmed/chemical/Radioisotopes,
http://linkedlifedata.com/resource/pubmed/chemical/Reserpine,
http://linkedlifedata.com/resource/pubmed/chemical/Rubidium,
http://linkedlifedata.com/resource/pubmed/chemical/Sodium-Potassium-Exchanging ATPase
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pubmed:status |
MEDLINE
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pubmed:month |
Feb
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pubmed:issn |
0006-2952
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
1
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pubmed:volume |
32
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
423-35
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pubmed:dateRevised |
2007-11-15
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pubmed:meshHeading |
pubmed-meshheading:6303346-Animals,
pubmed-meshheading:6303346-Cell Membrane,
pubmed-meshheading:6303346-Electric Stimulation,
pubmed-meshheading:6303346-Female,
pubmed-meshheading:6303346-Guinea Pigs,
pubmed-meshheading:6303346-Male,
pubmed-meshheading:6303346-Myocardium,
pubmed-meshheading:6303346-Ouabain,
pubmed-meshheading:6303346-Potassium Chloride,
pubmed-meshheading:6303346-Radioisotopes,
pubmed-meshheading:6303346-Reserpine,
pubmed-meshheading:6303346-Rubidium,
pubmed-meshheading:6303346-Sodium-Potassium-Exchanging ATPase,
pubmed-meshheading:6303346-Stimulation, Chemical
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pubmed:year |
1983
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pubmed:articleTitle |
Consequences of specific [3H]ouabain binding to guinea pig left atria and cardiac cell membranes.
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
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