Dual Ca2+ modulation of glycinergic synaptic currents in rodent hypoglossal motoneurons

Autor: Mukhtarov, Marat, Ragozzino, Davide, Bregestovski, Piotr
Přispěvatelé: Epilepsie et ischémie cérébrale, Université de la Méditerranée - Aix-Marseille 2-Institut National de la Santé et de la Recherche Médicale (INSERM), ipartimento di Fisiologia Umana e Farmacologia, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Istituto Neurologico Mediterraneo (NEUROMED I.R.C.C.S.), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA)-University of Naples Federico II = Università degli studi di Napoli Federico II, Tyzio, Roman, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome]-Università degli studi di Napoli Federico II
Rok vydání: 2005
Předmět:
Hypoglossal Nerve
MESH: Endocannabinoids
MESH: Rats
Sprague-Dawley
Synaptic Transmission
Membrane Potentials
Rats
Sprague-Dawley
Mice
Receptors
Glycine
Piperidines
MESH: Receptors
Cannabinoid
MESH: Presynaptic Terminals
MESH: Animals
Receptors
Cannabinoid
Motor Neurons
MESH: Naphthalenes
MESH: Neural Inhibition
MESH: Glutamic Acid
MESH: Glycine
MESH: N-Methylaspartate
MESH: Piperidines
MESH: Benzoxazines
MESH: Calcium
MESH: Hypoglossal Nerve
MESH: Receptors
Glycine
Rimonabant
MESH: Motor Neurons
Cell Physiology
N-Methylaspartate
MESH: Rats
Morpholines
Glycine
Presynaptic Terminals
Glutamic Acid
MESH: Morpholines
[SDV.BC]Life Sciences [q-bio]/Cellular Biology
In Vitro Techniques
Naphthalenes
Receptors
N-Methyl-D-Aspartate
Cannabinoid Receptor Modulators
MESH: Synaptic Transmission
Animals
MESH: Membrane Potentials
Rats
Wistar
[SDV.BC] Life Sciences [q-bio]/Cellular Biology
MESH: Mice
MESH: Receptors
N-Methyl-D-Aspartate
Neural Inhibition
MESH: Rats
Wistar
Benzoxazines
Rats
Pyrazoles
Calcium
MESH: Pyrazoles
Zdroj: The Journal of Physiology
The Journal of Physiology, 2005, 569 (Pt 3), pp.817-31. ⟨10.1113/jphysiol.2005.094862⟩
The Journal of Physiology, Wiley, 2005, 569 (Pt 3), pp.817-31. ⟨10.1113/jphysiol.2005.094862⟩
ISSN: 0022-3751
1469-7793
DOI: 10.1113/jphysiol.2005.094862⟩
Popis: International audience; Glycinergic synapses are implicated in the coordination of reflex responses, sensory signal processing and pain sensation. Their activity is pre- and postsynaptically regulated, although mechanisms are poorly understood. Using patch-clamp recording and Ca2+ imaging in hypoglossal motoneurones from rat and mouse brainstem slices, we address here the role of cytoplasmic Ca2+ (Ca(i)) in glycinergic synapse modulation. Ca2+ influx through voltage-gated or NMDA receptor channels caused powerful transient inhibition of glycinergic IPSCs. This effect was accompanied by an increase in both the failure rate and paired-pulse ratio, as well as a decrease in the frequency of mIPSCs, suggesting a presynaptic mechanism of depression. Inhibition was reduced by the cannabinoid receptor antagonist SR141716A and occluded by the agonist WIN55,212-2, indicating involvement of endocannabinoid retrograde signalling. Conversely, in the presence of SR141716A, glycinergic IPSCs were potentiated postsynaptically by glutamate or NMDA, displaying a Ca2(+)-dependent increase in amplitude and decay prolongation. Both presynaptic inhibition and postsynaptic potentiation were completely prevented by strong Ca(i) buffering (20 mm BAPTA). Our findings demonstrate two independent mechanisms by which Ca2+ modulates glycinergic synaptic transmission: (i) presynaptic inhibition of glycine release and (ii) postsynaptic potentiation of GlyR-mediated responses. This dual Ca2(+)-induced regulation might be important for feedback control of neurotransmission in a variety of glycinergic networks in mammalian nervous systems.
Databáze: OpenAIRE
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