Document Detail


Post-tetanic potentiation in the rat calyx of Held synapse.
MedLine Citation:
PMID:  15695246     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We studied synaptic plasticity in the calyx of Held synapse, an axosomatic synapse in the auditory brainstem, by making whole-cell patch clamp recordings of the principal cells innervated by the calyces in a slice preparation of 7- to 10-day-old rats. A 5 min 20 Hz stimulus train increased the amplitude of excitatory postsynaptic currents (EPSCs) on average more than twofold. The amplitude of the synaptic currents took several minutes to return to control values. The post-tetanic potentiation (PTP) was accompanied by a clear increase in the frequency, but not the amplitude, of spontaneous EPSCs, which returned to baseline more rapidly than the potentiation of evoked release. The size of the readily releasable pool of vesicles was increased by about 30%. In experiments in which presynaptic measurements of the intracellular calcium concentration were combined with postsynaptic voltage clamp recordings, PTP was accompanied by an increase in the presynaptic calcium concentration to about 210 nM. The decay of the PTP matched the decay of this increase. When the decay of the calcium transient was shortened by dialysing the terminal with EGTA, the PTP decay sped up in parallel. Our experiments suggest that PTP at the calyx of Held synapse is due to a long-lasting increase in the presynaptic calcium concentration following a tetanus, which results in an increase in the release probability of the vesicles of the readily releasable pool. Although part of the PTP can be explained by a direct activation of the calcium sensor for phasic release, other mechanisms are likely to contribute as well.
Authors:
Ron L P Habets; J Gerard G Borst
Related Documents :
2982166 - Transmission at voltage-clamped giant synapse of the squid: evidence for cooperativity ...
15745946 - The multiple functions of cysteine-string protein analyzed at drosophila nerve terminals.
4322706 - Adenosine 3',5'-monophosphate in nervous tissue: increase associated with synaptic tran...
214546 - Spontaneous multiquantal release at synapses in guinea-pig hypogastric ganglia: evidenc...
21098036 - Packing of the extracellular domain hydrophobic core has evolved to facilitate pentamer...
8590996 - 5-hydroxytryptamine-mediated effects of nicotine on endogenous gaba efflux from guinea-...
Publication Detail:
Type:  Comparative Study; In Vitro; Journal Article; Research Support, Non-U.S. Gov't     Date:  2005-02-03
Journal Detail:
Title:  The Journal of physiology     Volume:  564     ISSN:  0022-3751     ISO Abbreviation:  J. Physiol. (Lond.)     Publication Date:  2005 Apr 
Date Detail:
Created Date:  2005-03-29     Completed Date:  2005-08-18     Revised Date:  2013-06-09    
Medline Journal Info:
Nlm Unique ID:  0266262     Medline TA:  J Physiol     Country:  England    
Other Details:
Languages:  eng     Pagination:  173-87     Citation Subset:  IM    
Affiliation:
Department of Neuroscience, Erasmus MC, University Medical Center Rotterdam, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Brain Stem / drug effects,  physiology*
Calcium / pharmacology,  physiology
Excitatory Postsynaptic Potentials / drug effects,  physiology*
Neuronal Plasticity / drug effects,  physiology*
Rats
Rats, Wistar
Synapses / drug effects,  physiology*
Chemical
Reg. No./Substance:
7440-70-2/Calcium
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Experimental models of developmental programming: consequences of exposure to an energy rich diet du...
Next Document:  Modulation of sarcoplasmic reticulum Ca2+ release by glycolysis in cat atrial myocytes.