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001-es BibID:	BIBFORM018456
Első szerző:	Elfant, David
Cím:	Specific inhibitory synapses shift the balance from feedforward to feedback inhibition of hippocampal CA1 pyramidal cells / Elfant D., Pál B. Z., Emptage N., Capogna M.
Dátum:	2008
ISSN:	0953-816X
Megjegyzések:	Feedforward and feedback inhibition are two fundamental modes of operation widespread in the nervous system. We have functionally identified synaptic connections between rat CA1 hippocampal interneurons of the stratum oriens (SO) and interneurons of the stratum lacunosum moleculare (SLM), which can act as feedback and feedforward interneurons, respectively. The unitary inhibitory postsynaptic currents (uIPSCs) detected with K-gluconate-based patch solution at -50 mV had an amplitude of 20.0 +/- 2.0 pA, rise time 2.2 +/- 0.2 ms, decay time 25 +/- 2.2 ms, jitter 1.4 +/- 0.2 ms (average +/- SEM, n = 39), and were abolished by the gamma-aminobutyric acid (GABA)(A) receptor antagonist 2-(3-carboxypropyl)-3-amino-6-methoxyphenyl-pyridazinium bromide (SR 95531). Post hoc anatomical characterization revealed that all but one of the identified presynaptic neurons were oriens-lacunosum moleculare (O-LM) cells, whereas the postsynaptic neurons were highly heterogeneous, including neurogliaform (n = 4), basket (n = 4), Schaffer collateral-associated (n = 10) and perforant path-associated (n = 9) cells. We investigated the short-term plasticity expressed at these synapses, and found that stimulation at 10-40 Hz resulted in short-term depression of uIPSCs. This short-term plasticity was determined by presynaptic factors and was not target-cell specific. We found that the feedforward inhibition elicited by the direct cortical input including the perforant path onto CA1 pyramidal cells was modulated through the inhibitory synapses we have characterized. Our data show that the inhibitory synapses between interneurons of the SO and SLM shift the balance between feedback and feedforward inhibition onto CA1 pyramidal neurons.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban hippocampal neurons interneuron paired recording rat synaptic transmission
Megjelenés:	European Journal Of Neuroscience. - 27 : 1 (2008), p. 104-113. -
További szerzők:	Pál Balázs (1975-) (élettanász) Emptage, Nigel Capogna, Marco
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM018460
Első szerző:	Price, Christopher J.
Cím:	Group II and III mGluRs-mediated presynaptic inhibition of EPSCs recorded from hippocampal interneurons of CA1 stratum lacunosum moleculare / Price Christopher J., Karayannis Theofanis, Pál Balázs Zoltán, Capogna Marco
Dátum:	2005
ISSN:	0028-3908
Megjegyzések:	We have studied the effects of groups II and III metabotropic glutamate receptor (mGluR) activation on excitatory responses recorded from hippocampal interneurons of CA1 stratum lacunosum moleculare (SLM). Excitatory postsynaptic currents (EPSCs) evoked by stimulation of the perforant pathway were reduced either by the group II mGluR agonist LY354740 (50e100 nM,49.1G5.7% of control) or by the group III mGluR agonist L-2-amino-4-phosphonobutyric acid (L-AP4) (50 mM, 36.8G4.4% of control). Both drugs significantly enhanced paired-pulse facilitation of the EPSCs. Furthermore, both 100 nM LY354740 and 50 mM L-AP4 reduced the frequency, but not the amplitude, of miniature excitatory synaptic currents (mEPSCs), recorded in the presence of 1 mM TTX and 50 mM picrotoxin, or EPSCs evoked by perforant pathway stimulation in the presence of 2.5 mM Sr2C. The broad-spectrum mGluR antagonist LY341495 (10e50 mM) did not affect test EPSCs elicited 210 ms after stimulation at 100 Hz. At network level, 1e5 mM LY354740 significantly reduced the power of gamma frequency oscillations induced by 20 mM carbachol, 600 nM kainate and 5 mM KC in hippocampal CA1 area. Our results show powerful modulation of excitatory transmission impinging on interneurons of CA1 SLM by presynaptic group II or III mGluRs.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Neuropharmacology. - 49 : Suppl.1. (2005), p. 45-56. -
További szerzők:	Karayannis, Theofanis Pál Balázs (1975-) (élettanász) Capogna, Marco
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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