Search results for " glutamate"

Activation of phospholipases C and D by the novel metabotropic glutamate receptor agonist tADA.

1997

Abstract In hippocampal slices taken from 8-day-old rats, trans-azetidine-2,4-dicarboxylic acid (tADA), a novel glutamatergic agonist acting preferentially at class I mGluR receptors, activates phosphoinositide and phosphatidylcholine hydrolysis with widely different potencies. Inositol phosphate formation was maximally increased at 10 μM tADA ( ec 50: 1.2 μM), while phospholipase D activation was observed at a tADA concentration of 1 mM. This is the first report of a tADA-induced phospholipase D activity. © 1997 Elsevier Science Ltd. All rights reserved.

Ontogenetic and Pharmacological Studies on Metabotropic Glutamate Receptors Coupled to Phospholipase D Activation

1997

The present study was aimed at characterizing the metabotropic receptor subtype which is involved in the activation of phospholipase D (PLD) by glutamate in rat hippocampal slices. We first observed that the ontogenetic profile of glutamate-induced hydrolysis of phosphoinositides and of phosphatidylcholine was strikingly similar. Both pathways were significantly activated by glutamate in tissue taken from 3-, 8- and 15-day old rats, but not in adult rats. PLD activation was strongest in slices taken from 8-day old rats. At this age, quisqualate had a higher potency for PLD activation (EC50: 0.6 microM) than 1S,3R-ACPD (EC50: 16 microM) and DHPG, a specific activator of group I mGluR, was a …

El modulador alostérico negativo de los mGluR5, MPEP, potencia la reinstauración de la preferencia condicionada inducida con priming de cocaína

2019

Cocaine addiction is a chronic disorder with high relapse rates; therefore, understanding the neuronal mechanisms underlying drug-seeking during relapse is a priority to develop targeted pharmacotherapy. The metabotropic glutamate receptor 5 (mGluR5) seems to be involved in the reinstatement induced by cocaine-associated cues. The main objective of the study was to evaluate the efficacy of MPEP, a negative allosteric modulator of mGluR5, in attenuating or potentiating the reinstatement induced by priming doses of cocaine in the CPP paradigm, ultimately to further knowledge regarding the role of the mGluR5 in relapse into cocaine abuse. OF1 mice (48 female and 48 male) were conditioned in th…

Polycyclic Pyrrolo-Thiazole Systems with Biological Activity

Full and Partial Agonism of Ionotropic Glutamate Receptors Indicated by Molecular Dynamics Simulations

2011

Ionotropic glutamate receptors (iGluRs) are synaptic proteins that facilitate signal transmission in the central nervous system. Extracellular iGluR cleft closure is linked to receptor activation; however, the mechanism underlying partial agonism is not entirely understood. Full agonists close the bilobed ligand-binding domain (LBD), while antagonists prevent closure; the transmembrane ion channel either opens or stays closed, respectively. Although some bulky partial agonists produce intermediate iGluR-LBD closure, the available crystal structures also imply that the cleft can be shut with certain partial agonists. Recently, we have shown that the iGluR-LBD closure stage can be recreated b…

Etude du système glutamate décarboxylase-dépendant de Brucella

2013

Expression of metabotropic glutamate receptors in murine thymocytes and thymic stromal cells

2000

RT-PCR combined with immunoblotting showed the expression of group-I (mGlu1 and 5) and group-II (mGlu2 and 3) metabotropic glutamate receptors in whole mouse thymus, isolated thymocytes and TC-1S thymic stromal cell line. Cytofluorimetric analysis showed that mGlu-5 receptors were absent in CD4(-)/CD8(-) but present in more mature CD4(+) CD8(+) and CD4(+)CD8(-) thymocytes. mGlu-1a receptors showed an opposite pattern of expression with respect to mGlu5, whereas mGlu2/3 receptor expression did not differ between double negative and double positive cells. mGlu receptors expressed in both thymic cell components were functional, as indicated by measurements of polyphosphoinositide hydrolysis or…

Glutamatergic projection from the nucleus incertus to the septohippocampal system

2012

Abstract Recent findings support a relevant role of the nucleus incertus in the control of the hippocampal activity through the modulation of theta rhythm. Previous studies from our group have shown that this nucleus is a critical relay between reticularis pontis oralis and the medial septum/diagonal band, regarded as the main activator and the pacemaker of the hippocampal oscillations, respectively. Besides, the nucleus incertus is highly linked to activated states related to the arousal response. The neurotransmission of the nucleus incertus, however, remains uncertain. Only GABA and the neuromodulator relaxin 3 are usually considered to be involved in its contribution to the septohippoca…

Gray Matter NG2 Cells Display Multiple Ca2+-Signaling Pathways and Highly Motile Processes

2011

NG2 cells, the fourth type of glia in the mammalian CNS, receive synaptic input from neurons. The function of this innervation is unknown yet. Postsynaptic changes in intracellular Ca(2+)-concentration ([Ca(2+)](i)) might be a possible consequence. We employed transgenic mice with fluorescently labeled NG2 cells to address this issue. To identify Ca(2+)-signaling pathways we combined patch-clamp recordings, Ca(2+)-imaging, mRNA-transcript analysis and focal pressure-application of various substances to identified NG2-cells in acute hippocampal slices. We show that activation of voltage-gated Ca(2+)-channels, Ca(2+)-permeable AMPA-receptors, and group I metabotropic glutamate-receptors provo…

Characterization of the transporterB0AT3 (Slc6a17) in the rodent central nervous system.

2013

Abstract Background The vesicular B0AT3 transporter (SLC6A17), one of the members of the SLC6 family, is a transporter for neutral amino acids and is exclusively expressed in brain. Here we provide a comprehensive expression profile of B0AT3 in mouse brain using in situ hybridization and immunohistochemistry. Results We confirmed previous expression data from rat brain and used a novel custom made antibody to obtain detailed co-labelling with several cell type specific markers. B0AT3 was highly expressed in both inhibitory and excitatory neurons. The B0AT3 expression was highly overlapping with those of vesicular glutamate transporter 2 (VGLUT2) and vesicular glutamate transporter 1 (VGLUT1…