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rdf:type |
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lifeskim:mentions |
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pubmed:issue |
3
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pubmed:dateCreated |
2001-2-22
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pubmed:abstractText |
Analysis of presynaptic determinants of synaptic strength has been difficult at cortical synapses, mainly due to the lack of direct access to presynaptic elements. Here we report patch-clamp recordings from mossy fiber boutons (MFBs) in rat hippocampal slices. The presynaptic action potential is very short during low-frequency stimulation but is prolonged up to 3-fold during high-frequency stimulation. Voltage-gated K(+) channels in MFBs inactivate rapidly but recover from inactivation very slowly, suggesting that cumulative K(+) channel inactivation mediates activity-dependent spike broadening. Prolongation of the presynaptic voltage waveform leads to an increase in the number of Ca(2+) ions entering the terminal per action potential and to a consecutive potentiation of evoked excitatory postsynaptic currents at MFB-CA3 pyramidal cell synapses. Thus, inactivation of presynaptic K(+) channels contributes to the control of efficacy of a glutamatergic synapse in the cortex.
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pubmed:language |
eng
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pubmed:journal |
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pubmed:citationSubset |
IM
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pubmed:chemical |
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pubmed:status |
MEDLINE
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pubmed:month |
Dec
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pubmed:issn |
0896-6273
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pubmed:author |
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pubmed:issnType |
Print
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pubmed:volume |
28
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
927-39
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:11163277-Action Potentials,
pubmed-meshheading:11163277-Animals,
pubmed-meshheading:11163277-Calcium,
pubmed-meshheading:11163277-Elapid Venoms,
pubmed-meshheading:11163277-Electric Stimulation,
pubmed-meshheading:11163277-Excitatory Postsynaptic Potentials,
pubmed-meshheading:11163277-Glutamic Acid,
pubmed-meshheading:11163277-Ion Channel Gating,
pubmed-meshheading:11163277-Mossy Fibers, Hippocampal,
pubmed-meshheading:11163277-Patch-Clamp Techniques,
pubmed-meshheading:11163277-Potassium Channel Blockers,
pubmed-meshheading:11163277-Potassium Channels,
pubmed-meshheading:11163277-Presynaptic Terminals,
pubmed-meshheading:11163277-Rats,
pubmed-meshheading:11163277-Rats, Wistar,
pubmed-meshheading:11163277-Reaction Time,
pubmed-meshheading:11163277-Synaptic Transmission,
pubmed-meshheading:11163277-Tetraethylammonium,
pubmed-meshheading:11163277-Tetrodotoxin
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pubmed:year |
2000
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pubmed:articleTitle |
Dynamic control of presynaptic Ca(2+) inflow by fast-inactivating K(+) channels in hippocampal mossy fiber boutons.
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pubmed:affiliation |
Physiologisches Institut der Universität Freiburg, Hermann-Herder-Str. 7, D-79104, Freiburg, Germany.
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pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
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