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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5
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pubmed:dateCreated |
1983-3-17
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pubmed:abstractText |
The effects of Rb and Cs on the electrogenic Na-pump of the rabbit sinoatrial node cell were studied, using conventional microelectrode techniques. Hyperpolarizations induced by K or its substitutes were recorded from the preparations which were perfused previously with an extracellular K-free solution. The K-induced hyperpolarizations after K-depletion depended linearly on K-concentration in the range of 1.35 to 10.8 mM. When 2 mM Rb was used as an activator, a subthreshold oscillation appeared and the amplitude of the spontaneous action potentials in the Rb solution was larger than with the standard solution. As the concentration of Rb increased, the Rb-activated hyperpolarization increased, but the amplitude of the action potential decreased. In the case of Cs, the induced hyperpolarization was smaller than with K or Rb, and a transient recovery of pacemaker activity and gradual hyperpolarization preceded the true recovery in the standard solution. Since these hyperpolarization effects were not observed after the application of ouabain-containing K-free solution, the hyperpolarizations were considered to be electrogenic. A small hyperpolarization induced by activation of the external site of the Na-pump appears to be necessary for the immediate recovery of automatism from arrest at low resting potentials.
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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:issn |
0021-521X
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pubmed:author | |
pubmed:issnType |
Print
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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 |
843-54
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pubmed:dateRevised |
2007-3-21
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pubmed:meshHeading |
pubmed-meshheading:7154435-Action Potentials,
pubmed-meshheading:7154435-Animals,
pubmed-meshheading:7154435-Cesium,
pubmed-meshheading:7154435-Electrophysiology,
pubmed-meshheading:7154435-Female,
pubmed-meshheading:7154435-Male,
pubmed-meshheading:7154435-Potassium,
pubmed-meshheading:7154435-Rabbits,
pubmed-meshheading:7154435-Rubidium,
pubmed-meshheading:7154435-Sinoatrial Node,
pubmed-meshheading:7154435-Sodium
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pubmed:year |
1982
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pubmed:articleTitle |
Effects of Rb and Cs on the electrogenic Na-pump in rabbit sinoatrial node cells.
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pubmed:publicationType |
Journal Article
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