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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
8
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pubmed:dateCreated |
1995-4-11
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pubmed:abstractText |
Halothane is a potent bronchodilator. The effects of halothane on isolated canine tracheal smooth muscle contraction and intracellular Ca(2+) increment induced by a high concentration of K+ were investigated to clarify how this anaesthetic decreases intracellular Ca2+ concentration ([Ca2+]i), an important second messenger. The tension of the muscle strips was measured using an isometric transducer, and [Ca2+]i was measured using a surface fluorescence spectroscopy. Exposure to a 72.7 mM K+ solution increased muscle tension and [Ca2+]i. Halothane (1,2,3 and 4% at the vaporiser) was introduced by bubbling in the presence of the 72.7 mM K+, and significantly decreased both this elevated muscle tension and the [Ca2+]i in a concentration-dependent manner. Similarly, slowly decreasing concentrations of K+ (48.5, 36.4, 24.2 and 18.2 mM) significantly decreased both of these variables. There was no significant difference between the slopes of the two regression lines of changes in muscle tension and changes in [Ca2+]i. From the evidence that tonic increase in [Ca2+]i by high concentrations of K+ is due to the influx of Ca2+ via L-type voltage channels, halothane may modify the L-type channels to decrease Ca2+ influx. In conclusion, halothane inhibits the high K(+)-induced canine airway smooth muscle contraction by decreasing [Ca2+]i. The decrease in [Ca2+]i by halothane might be due to inhibition of voltage-operated channels, especially the L-type channels.
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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 |
Nov
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pubmed:issn |
0001-5172
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
38
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
816-9
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:7887104-Animals,
pubmed-meshheading:7887104-Calcium,
pubmed-meshheading:7887104-Dogs,
pubmed-meshheading:7887104-Halothane,
pubmed-meshheading:7887104-Muscle, Smooth,
pubmed-meshheading:7887104-Muscle Contraction,
pubmed-meshheading:7887104-Potassium,
pubmed-meshheading:7887104-Trachea
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pubmed:year |
1994
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pubmed:articleTitle |
Inhibitory effects of halothane on high(K+)-induced canine tracheal smooth muscle contraction and intracellular Ca2+ increment.
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pubmed:affiliation |
Department of Anesthesiology, Sapporo Medical University, School of Medicine, Hokkaido, Japan.
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pubmed:publicationType |
Journal Article,
In Vitro
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