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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4 Pt 1
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pubmed:dateCreated |
1994-6-9
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pubmed:abstractText |
The stimulating effect of excitation on the Na(+)-K+ pump was characterized in measurements of 22Na efflux, intracellular Na+ content, 86Rb influx, and [3H]ouabain binding in isolated rat soleus muscle. Direct stimulation (10 V, 1 ms, 2 Hz) rapidly increased 22Na efflux and 86Rb influx about twofold. These effects were blocked by tetracaine and ouabain, were not associated with any significant increase in intracellular Na+, and could not be attributed to a rise in extracellular K+. The stimulation of 22Na efflux was unaffected by tubocurarine, dantrolene, trifluoperazine, or bumetanide. Stimulation at 2 Hz increased the rate of [3H]ouabain binding by approximately 120% within 1 min, indicating an early specific activation of the Na(+)-K+ pump. Stimulation at 60 Hz for 10 s increased intracellular Na+ content by 58%. Reextrusion of Na+ was complete in 2 min and could be prevented by ouabain (10(-4) M) or by cooling to 0 degrees C. It is concluded that, in rat soleus muscle, excitation leads to a rapid and pronounced (up to 15-fold) stimulation of the Na(+)-K+ pump, even at modest increases in intracellular Na+. This activation mechanism may be essential for the maintenance of transmembrane Na(+)-K+ gradients and prompt recovery of excitability during contractile activity.
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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:month |
Apr
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pubmed:issn |
0002-9513
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
266
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
C925-34
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pubmed:dateRevised |
2007-11-15
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pubmed:meshHeading |
pubmed-meshheading:8178965-Animals,
pubmed-meshheading:8178965-Electric Stimulation,
pubmed-meshheading:8178965-Enzyme Activation,
pubmed-meshheading:8178965-Female,
pubmed-meshheading:8178965-Muscle Contraction,
pubmed-meshheading:8178965-Muscles,
pubmed-meshheading:8178965-Ouabain,
pubmed-meshheading:8178965-Rats,
pubmed-meshheading:8178965-Rats, Wistar,
pubmed-meshheading:8178965-Rubidium,
pubmed-meshheading:8178965-Sodium,
pubmed-meshheading:8178965-Sodium-Potassium-Exchanging ATPase
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pubmed:year |
1994
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pubmed:articleTitle |
Excitation-induced activation of the Na(+)-K+ pump in rat skeletal muscle.
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pubmed:affiliation |
Institute of Physiology, Aarhus University, Denmark.
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
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