Possible role of mitochondria in posttetanic potentiation of GABAergic synaptic transmission in rat neocortical cell cultures

Synapse 58:45-52, 2005. (c) 2005 Wiley-Liss, Inc..

It has been previously demonstrated that mitochondria are of crucial importance for posttetanic potentiation (PTP) at neuromuscular junction. The aim of our study was to examine whether this may also be the case at a central synapse. To address this question, we studied possible mitochondrial involvement in PTP of GABAergic synaptic transmission in rat neocortical cultures, a preparation in which PTP has not been previously documented. Synaptic responses were evoked by local extracellular stimulation. Whole-cell patch-clamp technique was employed to record inhibitory postsynaptic currents (IPSCs) from postsynaptic neurons. Tetanic stimulation (30 Hz, 4 s) of the presynaptic neuron evoked an increase of IPSC amplitude, lasting for about 1 min. PTP was accompanied by a decrease of coefficient of variation of the IPSC and a decrease of paired-pulse (IPSC(2)/IPSC(1)) ratio, indicating involvement of presynaptic mechanism(s) in PTP. Possible role of mitochondria in PTP was addressed using drugs affecting Ca(2+) uptake and subsequent Ca(2+) efflux: carbonyl cyanide 3-chlorophenylhydrazone (CCCP) and tetraphenylphosphonium ions (TPP(+)). It was found that both CCCP (1-2 microM) and TPP(+) (10 microM) either substantially decreased or eliminated PTP. These results further confirm presynaptic origin of PTP in neocortical neurons and suggest an important role of mitochondrial Ca(2+) turnover in this form of synaptic plasticity at the central synapse.

Medienart:

Artikel

Erscheinungsjahr:

2005

Erschienen:

2005

Enthalten in:

Zur Gesamtaufnahme - volume:58

Enthalten in:

Synapse (New York, N.Y.) - 58(2005), 1 vom: 15. Okt., Seite 45-52

Sprache:

Englisch

Beteiligte Personen:

Storozhuk, Maksim V [VerfasserIn]
Ivanova, Svetlana Y [VerfasserIn]
Balaban, Pavel M [VerfasserIn]
Kostyuk, Platon G [VerfasserIn]

Themen:

555-60-2
56-12-2
Carbonyl Cyanide m-Chlorophenyl Hydrazone
Comparative Study
Gamma-Aminobutyric Acid
Journal Article
Research Support, Non-U.S. Gov't
Uncoupling Agents

Anmerkungen:

Date Completed 28.06.2006

Date Revised 15.11.2006

published: Print

Citation Status MEDLINE

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM156731940