Search results for "glutamate receptor"
showing 10 items of 219 documents
Nitric oxide modulates striatal neuronal activity via soluble guanylyl cyclase: an in vivo microiontophoretic study in rats.
2003
It is now well established that nitric oxide (NO) acts as a neuromodulator in the central nervous system. To assess the role of NO in modulating striatal activity, single-unit recording was combined with iontophoresis to study presumed spiny projection neurons in urethane-anesthetized male rats. Striatal neurons recorded were essentially quiescent and were therefore activated to fire by the iontophoretic administration of glutamate, pulsed in cycles of 30 sec on and 40 sec off. In this study, iontophoresis of 3-morpholinosydnonimine hydrochloride (SIN 1), a nitric oxide donor, produced reproducible, current-dependent inhibition of glutamate-induced excitation in 12 of 15 striatal neurons, r…
Structural Mechanism of N-Methyl-D-Aspartate Receptor Type 1 Partial Agonism
2012
N-methyl-D-aspartate (NMDA) receptors belong to a family of ionotropic glutamate receptors that contribute to the signal transmission in the central nervous system. NMDA receptors are heterotetramers that usually consist of two GluN1 and GluN2 monomers. The extracellular ligand-binding domain (LBD) of a monomer is comprised of discontinuous segments that form the functional domains D1 and D2. While the binding of a full agonist glycine to LBD of GluN1 is linked to cleft closure and subsequent ion-channel opening, partial agonists are known to activate the receptor only sub-maximally. Although the crystal structures of the LBD of related GluA2 receptor explain the mechanism for the partial a…
Role of N-methyl-D-aspartate receptors in the long-term effects of repeated social defeat stress on the rewarding and psychomotor properties of cocai…
2019
Abstract Exposure to social stress increases the vulnerability of experimental animals to the rewarding effects of cocaine and it has been suggested that the glutamatergic system could be involved in these effects of stress. The aim of this work is to determine the role of N-methyl- d -aspartate (NMDA) glutamate receptors in the influence of social stress on the conditioned place preference and locomotor sensitization induced by cocaine. Mice treated with saline or NMDA antagonist memantine (5 or 10 mg/kg) underwent repeated social defeat or were kept in the exploration control condition. After three weeks, all groups (SAL + RSD, M5 + RSD, M10 + RSD, SAL + EXP, M5 + EXP and M10 + EXP) were …
The Proteoglycan NG2 Is Complexed with α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid (AMPA) Receptors by the PDZ Glutamate Receptor Interactio…
2003
The proteoglycan NG2 is expressed by immature glial cells in the developing and adult central nervous system. Using the COOH-terminal region of NG2 as bait in a yeast two-hybrid screen, we identified the glutamate receptor interaction protein GRIP1, a multi-PDZ domain protein, as an interacting partner. NG2 exhibits a PDZ binding motif at the extreme COOH terminus which binds to the seventh PDZ domain of GRIP1. In addition to the published expression in neurons, GRIP1 is expressed by immature glial cells. GRIP1 is known to bind to the GluRB subunit of the AMPA glutamate receptor expressed by subpopulations of neurons and immature glial cells. In cultures of primary oligodendrocytes, cells c…
Presynaptic nitric oxide/cGMP facilitates glutamate release via hyperpolarization-activated cyclic nucleotide-gated channels in the hippocampus
2011
In hippocampal neurons, synaptic transmission is affected by a variety of modulators, including nitric oxide (NO), which was proposed as a retrograde messenger as long as two decades ago. NO signals via two NO-sensitive guanylyl cyclases (NO-GCs) (NO-GC1 and NO-GC2) and the subsequent increase in cGMP. Lack of long-term potentiation in mice deficient in either one of the two NO-GCs demonstrates the involvement of both NO-GCs in synaptic transmission. However, the physiological consequences of NO/cGMP and the cellular mechanisms involved are unknown. Here, we analyzed glutamatergic synaptic transmission, most likely reflecting glutamate release, in the hippocampal CA1 region of NO-GC knockou…
NMDA receptor antagonist treatment increases the production of new neurons in the aged rat hippocampus
2002
The production of new neurons declines during adulthood and persists, although at very low levels, in the aged hippocampus. Since neurogenesis in young adults has been related to learning and memory, its reduction may contribute to the age-related impairments in these abilities. Adrenalectomy (ADX) enhances neurogenesis in the aged hippocampus, although it also induces neuronal cell death. Since the administration of an NMDA receptor antagonist enhances neurogenesis in young adult rats without deleterious morphological effects, we have tested whether neurogenesis could be reactivated in aged rats. Our study shows that cell proliferation, cell death, neurogenesis and the number of radial gli…
Putative Role of Taurine as Neurotransmitter During Perinatal Cortical Development
2017
Neurotransmitters and neuronal activity affect neurodevelopmental events like neurogenesis, neuronal migration, apoptosis and differentiation. Beside glutamate and gamma-amino butyric acid, the aminosulfonic acid taurine has been considered as possible neurotransmitter that influences early neuronal development. In this article I review recent studies of our group which demonstrate that taurine can affect a variety of identified neuronal populations in the immature neocortex and directly modulates neuronal activity. These experiments revealed that taurine evoke dose-dependent membrane responses in a variety of neocortical neuron populations, including Cajal-Retzius cells, subplate neurons a…
Glial Protection Against Neuronal Damage
1997
Glial homeostatic mechanisms are involved in neuronal protection during the early phase of cerebral ischemia. These protective effects include, among others, glutamate uptake and the regulation of pH in the extracellular space of the brain. Uptake of glutamate goes along with glial swelling, as does the elimination of protons from the glial cytosol. Five transport systems interact in order to maintain a normal intra- and extracellular pH in the brain.
Pro-inflammatory T helper 17 directly harms oligodendrocytes in neuroinflammation.
2021
Significance Multiple sclerosis (MS) is a neuroinflammatory, demyelinating disease that represents one of the most frequent causes of irreversible disability in young adults. Treatment options to halt disability are limited. We discovered that T helper (Th)17 cells in contact with oligodendrocytes produce higher levels of glutamate and induce significantly greater oligodendrocyte damage than their Th2 counterpart. Blockade of CD29, which is linked to glutamate release pathways and expressed in high levels on Th17 cells, preserved human oligodendrocyte processes from Th17-mediated injury. Our data thus provide evidence for the direct and deleterious attack of Th17 cells on the myelin compart…
The Effects of N-Acetylcysteine on the Rat Mesocorticolimbic Pathway: Role of mGluR5 Receptors and Interaction with Ethanol
2021
N-acetylcysteine (NAC) is a prodrug that is marketed as a mucolytic agent and used for the treatment of acetaminophen overdose. Over the last few decades, evidence has been gathered that suggests the potential use of NAC as a new pharmacotherapy for alcohol use disorder (AUD), although its mechanism of action is already being debated. In this paper, we set out to assess both the potential involvement of the glutamate metabotropic receptors (mGluR) in the possible dual effect of NAC administered at two different doses and NAC’s effect on ethanol-induced activation. To this aim, 30 or 120 mg/kg of NAC was intraperitoneally administered to rats with the presence or absence of the negative allo…