Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Postsynaptic hyperpolarization increases the strength of AMPA-mediated synaptic transmission at large synapses between mossy fibers and CA3 pyramidalcells
Autore:
Berretta, N; Rossokhin, AV; Kasyanov, AM; Sokolov, MV; Cherubini, E; Voronin, LL;
Indirizzi:
Int Sch Adv Studies, Program Neurosci, I-34014 Trieste, Italy Int Sch Adv Studies Trieste Italy I-34014 urosci, I-34014 Trieste, Italy Int Sch Adv Studies, INFM Unit, I-34014 Trieste, Italy Int Sch Adv Studies Trieste Italy I-34014 M Unit, I-34014 Trieste, Italy Russian Acad Med Sci, Inst Brain Res, Moscow 103064, Russia Russian Acad Med Sci Moscow Russia 103064 ain Res, Moscow 103064, Russia Russian Acad Sci, Inst Higher Nervous Act & Neurophysiol, Moscow 117865, Russia Russian Acad Sci Moscow Russia 117865 europhysiol, Moscow 117865, Russia Leibniz Inst Neurobiol, D-39008 Magdeburg, Germany Leibniz Inst NeurobiolMagdeburg Germany D-39008 9008 Magdeburg, Germany
Titolo Testata:
NEUROPHARMACOLOGY
fascicolo: 12, volume: 39, anno: 2000,
pagine: 2288 - 2301
SICI:
0028-3908(2000)39:12<2288:PHITSO>2.0.ZU;2-X
Fonte:
ISI
Lingua:
ENG
Soggetto:
LONG-TERM POTENTIATION; HIPPOCAMPAL SLICES; QUANTAL ANALYSIS; VISUAL-CORTEX; NEURONS; FACILITATION; PLASTICITY; CURRENTS; GLUTAMATE; RELEASE;
Keywords:
CA3 synapses; retrograde signaling; postsynaptic membrane potential; ephaptic feedback; failures; quantal analysis;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
45
Recensione:
Indirizzi per estratti:
Indirizzo: Cherubini, E Int Sch Adv Studies, Program Neurosci, Via Beirut 2-4, I-34014 Trieste, Italy Int Sch Adv Studies Via Beirut 2-4 Trieste Italy I-34014 aly
Citazione:
N. Berretta et al., "Postsynaptic hyperpolarization increases the strength of AMPA-mediated synaptic transmission at large synapses between mossy fibers and CA3 pyramidalcells", NEUROPHARM, 39(12), 2000, pp. 2288-2301

Abstract

In chemical synapses information flow is polarized. However, the postsynaptic cells can affect transmitter release via retrograde chemical signaling. Here we explored the hypothesis that, in large synapses, having large synaptic cleft resistance, transmitter release can be enhanced by electrical (ephaptic) signaling due to depolarization of the presynaptic release site induced by the excitatory postsynaptic current itself. The hypothesis predicts that, in such synapses, postsynaptic hyperpolarization would increase response amplitudes isupralinearly", i.e. stronger than predicted from the driving force shift. We found supralinear increases in the amplitude of minimal excitatory postsynaptic potential (EPSP) during hyperpolarization of CA3 pyramidal neurons. Failure rate, paired-pulse facilitation, coefficient of variation of the EPSP amplitude and EPSP quantal content were also modified. The effects were especially strong on mossy fiber EPSPs (MF-EPSPs) mediated by the activation of large synapses and identified pharmacologically or by their kinetics. The effects were weaker on commissural fiber EPSPs mediated by smaller and more remote synapses. Even spontaneous membrane potential fluctuations were associated with supralinear MF-EPSP increases and failure rate reduction. The results suggest the existence of a novel mechanism for retrograde control of synaptic efficacy from postsynaptic membrane potential and are consistent with the ephaptic feedback hypothesis. (C) 2000 Elsevier Science Ltd. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 29/09/20 alle ore 22:36:11