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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3 Pt 1
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pubmed:dateCreated |
1993-11-23
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pubmed:abstractText |
The endothelium plays an important role in the modulation of vascular tone and blood cell activation. Extensive work has demonstrated that the release of endothelium-derived relaxing factor (EDRF) from the endothelium is evoked by a number of physical and chemical stimuli requiring Ca2+. Because endothelial cells do not express voltage-dependent Ca2+ channels, Ca2+ influxes following receptor activation may be facilitated by cell hyperpolarizations mediated by the activation of K+ conductances. There has been recent interest in the role of ATP-sensitive K+ channels (KATP) suggesting that KATP may play a role in the regulation of blood flow. We have investigated the electrophysiological properties of an ATP-sensitive K+ conductance in whole cell and membrane patches from rat aorta and brain microvascular endothelial cells. Whole cell as well as single-channel currents were increased by either intracellular dialysis of ATP or application of glucose-free/NaCN (2 mM) solutions. Both currents were reversibly blocked by glibenclamide (1-100 microM). The KATP channel opener pinacidil (30 microM) caused activation of an outward current in the presence of physiological intracellular ATP concentrations. In inside-out patches, 10 microM-1 mM ATP invariably caused a dramatic decrease in channel activity. We conclude that both rat aorta and brain microvascular endothelial cells express KATP channels. KATP may play a role in the regulation of endothelial cell resting potential during impaired energy supply and therefore modulate EDRF release and thus cerebral blood flow.
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pubmed:grant | |
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 |
Sep
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pubmed:issn |
0002-9513
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
265
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
C812-21
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:8214038-Adenosine Triphosphate,
pubmed-meshheading:8214038-Animals,
pubmed-meshheading:8214038-Aorta,
pubmed-meshheading:8214038-Cell-Free System,
pubmed-meshheading:8214038-Cells, Cultured,
pubmed-meshheading:8214038-Cerebrovascular Circulation,
pubmed-meshheading:8214038-Electrophysiology,
pubmed-meshheading:8214038-Endothelium, Vascular,
pubmed-meshheading:8214038-Guanidines,
pubmed-meshheading:8214038-Microcirculation,
pubmed-meshheading:8214038-Pinacidil,
pubmed-meshheading:8214038-Potassium Channels,
pubmed-meshheading:8214038-Rats
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pubmed:year |
1993
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pubmed:articleTitle |
ATP-sensitive K+ channels in rat aorta and brain microvascular endothelial cells.
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pubmed:affiliation |
Department of Neurological Surgery, University of Washington, Seattle 98104.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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