Source:http://linkedlifedata.com/resource/pubmed/id/10652186
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
2000-4-18
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pubmed:abstractText |
We investigated effects of external acidosis on HERG current expressed in Xenopus oocytes. HERG current was rapidly and reversibly suppressed by external acidosis in a voltage-independent manner. The slope conductance was decreased from 143 +/- 11 to 93.4 +/- 6.8 microS by changing external pH (pH(o)) from 7.6 to 6.0 (P<0.05). Steady-state activation was shifted by about 20 mV in a depolarized direction with a change from pH(o) 7.6 to 6.0, while steady-state inactivation was not significantly changed. Activation time constants were increased, deactivation and recovery time constants were decreased, while those of inactivation showed no significant change. When external K(+) concentration ([K(+)](o)) was increased from 2 mM to 10 mM, a ratio of slope conductance at pH(o) 6.0 to pH(o) 7.6 was significantly smaller in 2 mM (pH(o) 6.0/pH(o) 7.6 = 0.65 +/- 0.04) than in 10 mM[K(+)](o) (0.83 +/- 0.06, P<0.05). The changes in activation, deactivation and recovery from inactivation were not affected by change in [K(+)](o). The results indicated that external acidosis suppressed HERG current mainly by shifting the voltage-dependence of the activation and deactivation kinetics, and partly by decreasing slope conductance. Moreover, the reduction of HERG current could be partly antagonized with increasing [K(+)](o).
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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/Cation Transport Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Ether-A-Go-Go Potassium Channels,
http://linkedlifedata.com/resource/pubmed/chemical/KCNH6 protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels,
http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels, Voltage-Gated
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pubmed:status |
MEDLINE
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pubmed:month |
Jan
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pubmed:issn |
0022-2828
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pubmed:author | |
pubmed:copyrightInfo |
Copyright 2000 Academic Press.
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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 |
11-21
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:10652186-Animals,
pubmed-meshheading:10652186-Cation Transport Proteins,
pubmed-meshheading:10652186-Electric Conductivity,
pubmed-meshheading:10652186-Ether-A-Go-Go Potassium Channels,
pubmed-meshheading:10652186-Hydrogen-Ion Concentration,
pubmed-meshheading:10652186-Kinetics,
pubmed-meshheading:10652186-Oocytes,
pubmed-meshheading:10652186-Potassium Channels,
pubmed-meshheading:10652186-Potassium Channels, Voltage-Gated,
pubmed-meshheading:10652186-Xenopus laevis
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pubmed:year |
2000
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pubmed:articleTitle |
Effects of external acidosis on HERG current expressed in Xenopus oocytes.
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pubmed:affiliation |
Department of 1st Internal Medicine, School of Medicine, Tokyo, 113-8510, Japan.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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