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001-es BibID:	BIBFORM060025
Első szerző:	Kőszeghy Áron (Ph.D hallgató, élettanász)
Cím:	Endocannabinoid signaling modulates neurons of the pedunculopontine nucleus (PPN) via astrocytes. / Áron Kőszeghy, Adrienn Kovács, Tamás Bíró, Péter Szűcs, János Vincze, Zoltán Hegyi, Miklós Antal, Balázs Pál
Dátum:	2015
Megjegyzések:	The pedunculopontine nucleus (PPN) is known as the cholinergic part of the reticular activating system (RAS) and it plays an important role in transitions of slow-wave sleep to REM sleep and wakefulness. Although both exogenous and endocannabinoids affect sleep, the mechanism of endocannabinoid neuromodulation has not been characterized at cellular level in the PPN. In this paper, we demonstrate that both neurons and glial cells from the PPN respond to cannabinoid type 1 (CB1) receptor agonists. The neuronal response can be depolarization or hyperpolarization, while astrocytes exhibit more frequent calcium waves. All these effects are absent in CB1 gene-deficient mice. Blockade of the fast synaptic neurotransmission or neuronal action potential firing does not change the effect on the neuronal membrane potential significantly, while inhibition of astrocytic calcium waves by thapsigargin diminishes the response. Inhibition of group I metabotropic glutamate receptors (mGluRs) abolishes hyperpolarization, whereas blockade of group II mGluRs prevents depolarization. Initially active neurons and glial cells display weaker responses partially due to the increased endocannabinoid tone in their environment. Taken together, we propose that cannabinoid receptor stimulation modulates PPN neuronal activity in the following manner: active neurons may elicit calcium waves in astrocytes via endogenous CB1 receptor agonists. Astrocytes in turn release glutamate that activates different metabotropic glutamate receptors of neurons and modulate PPN neuronal activity.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban Endocannabinoid Pedunculopontine nucleus CB1 receptor Neuromodulation Astrocyte Metabotropic glutamate receptor
Megjelenés:	Brain structure and function 220 : 5 (2015), p. 3023-3041. -
További szerzők:	Kovács Adrienn (1989-) (molekuláris biológus) Bíró Tamás (1968-) (élettanász) Szűcs Péter (1974-) (kutatóorvos) Vincze János (1988-) (orvos) Hegyi Zoltán (1983-) (molekuláris biológus) Antal Miklós (1951-) (orvos, anatómus) Pál Balázs (1975-) (élettanász)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM037816
Első szerző:	Kőszeghy Áron (Ph.D hallgató, élettanász)
Cím:	Activation of muscarinic receptors increases the activity of the granule neurones of the rat dorsal cochlear nucleus : a calcium imaging study / Áron Kőszeghy, János Vincze, Zoltán Rusznák, Yuhong Fu, George Paxinos, László Csernoch, Géza Szücs
Dátum:	2012
ISSN:	0031-6768
Megjegyzések:	Acetylcholine modulates the function of the cochlear nucleus via several pathways. In this study the effects of cholinergic stimulation were studied on the cytoplasmic Ca2+ concentration of granule neurones of the rat dorsal cochlear nucleus (DCN). Ca2+ transients were recorded in Oregon-Green-BAPTA 1-loaded brain slices using a calcium imaging technique. For the detection, identification, and characterisation of the Ca2+ transients, a wavelet analysis-based method was developed. Granule cells were identified on the basis of their size and localisation. The action potential-coupled character of the Ca2+ transients of the granule cells was established by recording fluorescence changes and electrical activity simultaneously. Application of the cholinergic agonist carbamyl-choline (CCh) significantly increased the frequency of the Ca2+ transients (from 0.37 to 6.31 min-1, corresponding to a 17.1-fold increase; n = 89). This effect was antagonised by atropine, whereas CCh could still evoke an 8.3-fold increase of the frequency of the Ca2+ transients when hexamethonium was present. Using immunolabelling, the expression of both type 1 and type 3 muscarinic receptors (M1 and M3 receptors, respectively) was demonstrated in the granule cells. Application of 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (an M3-specific antagonist) prevented the onset of the CCh effect, whereas an M1-specific antagonist (pirenzepine) was less effective. We conclude that cholinergic stimulation increases the activity of granule cells, mainly by acting on their M3 receptors. The modulation of the firing activity of the granule cells, in turn, may modify the firing of projection neurones, and may adjust signal processing in the entire DCN.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Pflügers Archiv. - 463 : 6 (2012), p. 829-844. -
További szerzők:	Vincze János (1988-) (orvos) Rusznák Zoltán (1965-) (élettanász) Fu, YuHong Paxinos, George Csernoch László (1961-) (élettanász) Szűcs Géza (1948-) (élettanász)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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