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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
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pubmed:dateCreated |
1986-7-29
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pubmed:abstractText |
In rats under urethane or pentobarbitone anesthesia, Ca2+ -sensitive microelectrodes were inserted into CA3 and CA1 hippocampal cells. In 23 neurons with a mean resting membrane potential (Vm) of -56.9 mV, the Ca potential (VCa) fell below Vm by an average of -22.1 mV (S.D. +/- 19.1 mV), indicating a mean intracellular free Ca2+ concentration ([Ca]i) of 9.7 microM (S.D. 14.9 microM). In spite of their better and more stable Vm (mean -67.1 mV), unresponsive cells (probably neuroglia) had a higher and more variable [Ca]i (mean 37.0 +/- 51.2 microM). In 21 of the neurons, repetitive stimulation of the fimbria--at 5-20 Hz for 30s, which is sufficient to elicit bursts of population spikes--evoked substantial increases in [Ca]i: the mean increase observed during or just after 29 such tetani was +27.1 +/- 54.5 microM. Typically [Ca]i reached a peak near the end of the tetanus and then decayed with a half-time of 5-10 s, though not necessarily to the initial level. In 7 cells, a large increase in [Ca] (mean +239 +/- 367 microM) appeared as a late event, 20-30 s after the end of the tetanus. In 5 cells, [Ca]i could thus be raised transiently to 10(-4) M or higher. All these increases in [Ca]i are far greater than can be evoked by tetanic activation in spinal motoneurons; their possible significance for long term potentiation or cell necrosis in the hippocampus is discussed.
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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 |
May
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pubmed:issn |
0006-8993
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
21
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pubmed:volume |
374
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1-11
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:3719320-Animals,
pubmed-meshheading:3719320-Body Fluids,
pubmed-meshheading:3719320-Calcium,
pubmed-meshheading:3719320-Cell Count,
pubmed-meshheading:3719320-Electric Stimulation,
pubmed-meshheading:3719320-Evoked Potentials,
pubmed-meshheading:3719320-Hippocampus,
pubmed-meshheading:3719320-Intracellular Fluid,
pubmed-meshheading:3719320-Neuroglia,
pubmed-meshheading:3719320-Neurons,
pubmed-meshheading:3719320-Rats,
pubmed-meshheading:3719320-Rats, Inbred Strains,
pubmed-meshheading:3719320-Reaction Time
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pubmed:year |
1986
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pubmed:articleTitle |
Changes in free calcium ion concentration recorded inside hippocampal pyramidal cells in situ.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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