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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1997-12-22
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pubmed:abstractText |
Many studies have demonstrated that astrocytes respond with fluctuations in intracellular calcium concentration ([Ca2+]i) and membrane potential following the application of a number of ligands. Moreover, calcium (Ca2+) waves that spread through astrocytic syncitia have been described in numerous reports. We had the rare opportunity to study Ca2+ responses in astrocytes obtained from a patient diagnosed with Rasmussen's encephalitis, a rare form of intractable epilepsy. Using the ratiometric fluorescent indicator fura-2, we observed large spontaneous [Ca2+]i oscillations. The mean time between initial rise in [Ca2+]i and the return to baseline was 5.1 +/- 0.19 minutes (SEM; n = 201) and [Ca2+]i increased to a mean level of 271 +/- 8 nM (SEM; n = 201) from a baseline of 136 +/- 6 nM (SEM; n = 201). Removal of Ca2+ from the perfusion solution combined with the addition of the Ca2+ chelator EGTA (2 mM) completely but reversibly eliminated all oscillations suggesting the fluctuations were dependent on Ca2+ flux across the membrane. The percentage of cells undergoing spontaneous changes in [Ca2+]i decreased over time in culture. At 10-11 days postsurgery, approximately 70% of the cells were exhibiting this behavior, and by day 23 transients were no longer observed. We did not observe comparable spontaneous [Ca2+]i oscillations in rat cortical astrocytes. The potential that the spontaneous [Ca2+]i oscillations observed may be a unique feature of epileptic tissues is discussed.
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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 |
Nov
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pubmed:issn |
0894-1491
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
21
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
332-7
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pubmed:dateRevised |
2007-11-14
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pubmed:meshHeading |
pubmed-meshheading:9383042-Astrocytes,
pubmed-meshheading:9383042-Calcium,
pubmed-meshheading:9383042-Cells, Cultured,
pubmed-meshheading:9383042-Cerebral Cortex,
pubmed-meshheading:9383042-Child, Preschool,
pubmed-meshheading:9383042-Encephalitis,
pubmed-meshheading:9383042-Epilepsy,
pubmed-meshheading:9383042-Female,
pubmed-meshheading:9383042-Humans,
pubmed-meshheading:9383042-Time Factors
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pubmed:year |
1997
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pubmed:articleTitle |
Spontaneous intracellular calcium oscillations in cortical astrocytes from a patient with intractable childhood epilepsy (Rasmussen's encephalitis).
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pubmed:affiliation |
Department of Neurobiology, University of Alabama at Birmingham, 35294, USA.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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