Search results for "N-methyl-d-aspartate"
showing 10 items of 97 documents
D1/D5 modulation of synaptic NMDA receptor currents.
2009
Converging evidence suggests that salience-associated modulation of behavior is mediated by the release of monoamines and that monoaminergic activation of D1/D5receptors is required for normal hippocampal-dependent learning and memory. However, it is not understood how D1/D5modulation of hippocampal circuits can affect salience-associated learning and memory. We have observed in CA1 pyramidal neurons that D1/D5receptor activation elicits a bidirectional long-term plasticity of NMDA receptor-mediated synaptic currents with the polarity of plasticity determined by NMDA receptor, NR2A/B subunit composition. This plasticity results in a decrease in the NR2A/NR2B ratio of subunit composition. Sy…
Functional Synaptic Projections onto Subplate Neurons in Neonatal Rat Somatosensory Cortex
2002
Subplate neurons (SPn) play an important role in the formation of thalamocortical connections during early development and show glutamatergic and GABAergic spontaneous synaptic activity. We characterized these synaptic inputs by performing whole-cell recordings from SPn in somatosensory cortical slices of postnatal day 0-3 rats. At -70 mV, electrical stimulation of the thalamocortical afferents elicited in 68% of the SPn a monosynaptic CNQX-sensitive postsynaptic current (PSC). These fast PSCs were mediated by AMPA receptors, because they were prolonged by cyclothiazide and blocked by GYKI 52466. On membrane depolarization, thalamocortical stimulation elicited in 50% of the cells an additio…
Neurosteroid modulation of the presynaptic NMDA receptors regulating hippocampal noradrenaline release in normal rats and those exposed prenatally to…
2003
Abstract Prenatal exposure to diazepam (DZ), a positive allosteric modulator of the γ-aminobutyric acidA (GABAA) receptor complex, exerts profound effects that become more evident during puberty and in many cases are sex-specific, suggesting that such exposure interferes with the activity of steroid hormones. Apart from their well known effects on the genome, the reduced metabolites of many steroid hormones also interact directly with membrane receptors, including those for N-methyl- d -aspartate (NMDA). In this study, we compared the effects of several neurosteroids on NMDA receptors from normal rats and those exposed in utero to DZ (1.25 mg/kg per day) from the 14th through the 20th day o…
Delineation of molecular pathway activities of the chronic antidepressant treatment response suggests important roles for glutamatergic and ubiquitin…
2017
AbstractThe aim of this study was to identify molecular pathways related to antidepressant response. We administered paroxetine to the DBA/2J mice for 28 days. Following the treatment, the mice were grouped into responders or non-responders depending on the time they spent immobile in the forced swim test. Hippocampal metabolomics and proteomics analyses revealed that chronic paroxetine treatment affects glutamate-related metabolite and protein levels differentially in the two groups. We found significant differences in the expression of N-methyl-d-aspartate receptor and neuronal nitric oxide synthase proteins between the two groups, without any significant alterations in the respective tra…
Oligodendrocyte precursor cells modulate the neuronal network by activity-dependent ectodomain cleavage of glial NG2.
2014
The role of glia in modulating neuronal network activity is an important question. Oligodendrocyte precursor cells (OPC) characteristically express the transmembrane proteoglycan nerve-glia antigen 2 (NG2) and are unique glial cells receiving synaptic input from neurons. The development of NG2+ OPC into myelinating oligodendrocytes has been well studied, yet the retention of a large population of synapse-bearing OPC in the adult brain poses the question as to additional functional roles of OPC in the neuronal network. Here we report that activity-dependent processing of NG2 by OPC-expressed secretases functionally regulates the neuronal network. NG2 cleavage by the α-secretase ADAM10 yields…
N-methyl-d-aspartate receptor expression during adult neurogenesis in the rat dentate gyrus.
2006
Abstract N -methyl- d -aspartate (NMDA) receptors play a crucial role in the regulation of neuronal development during embryogenesis and they also regulate the rate of neurogenesis and proliferation in the adult dentate gyrus. However, the mechanism by which they influence these processes is not fully understood. NMDA receptors seem to be functional in hippocampal precursor cells and recently generated granule neurons, although there is no anatomical correlate of these physiological observations. We have analyzed the expression of the NMDA receptor subunits NR1 and NR2B in precursor cells and recently generated granule neurons of the adult rat dentate gyrus, using 5′bromodeoxyuridine, green…
Depletion of polysialic acid from neural cell adhesion molecule (PSA-NCAM) increases CA3 dendritic arborization and increases vulnerability to excito…
2012
Chronic immobilization stress (CIS) shortens apical dendritic trees of CA3 pyramidal neurons in the hippocampus of the male rat, and dendritic length may be a determinant of vulnerability to stress. Expression of the polysialylated form of neural cell adhesion molecule (PSA-NCAM) in the hippocampal formation is increased by stress, while PSA removal by Endo-neuraminidase-N (endo-N) is known to cause the mossy fibers to defasciculate and synapse ectopically in their CA3 target area. We show here that enzymatic removal of PSA produced a remarkable expansion of dendritic arbors of CA3 pyramidal neurons, with a lesser effect in CA1. This expansion eclipsed the CIS-induced shortening of CA3 dend…
Differential effect of beta-N-oxalylamino-L-alanine, the Lathyrus sativus neurotoxin, and (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate …
2000
We studied the effect of beta-oxalylamino-L-alanine, a glutamate analog present in Lathyrus sativus seeds and implicated in the etiopathogenesis of neurolathyrism, and (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate on the extracellular levels of aspartate, glutamate and taurine in the primary motor cortex of freely moving rats. We found that while both neurotoxins increase the level of aspartate and glutamate, only (+/-)-alpha(-amino-3-hydroxy-5-methylisoxazole-4-propionate is able to modulate the level of taurine. GYKI-52466, a non-competitive non-NMDA antagonist, inhibited beta-oxalylamino-L-alanine-induced increase of aspartate, but not that of glutamate. Conversely, this ant…
Role of NMDA and AMPA glutamatergic receptors in the effects of social defeat on the rewarding properties of MDMA in mice
2019
Exposure to social stress alters the response to drugs of abuse of experimental animals. Changes in the glutamatergic system seem to play a role in the effects of social defeat stress on the rewarding properties of cocaine and amphetamine. The aim of the present study was to evaluate the involvement of N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors in the effects of social defeat on the conditioned place preference induced by 3,4-methylenedioxymethamphetamine (MDMA). Our hypothesis was that changes in these receptors could mediate the effects of social defeat on MDMA reward. Young adult male mice were exposed to an episode…
Behavioural parameters in aged rats are related to LTP and gene expression of ChAT and NMDA-NR2 subunits in the striatum.
2004
Striatal parameters were assessed for their relevance to age-related behavioural decline. Forty aged rats (28-30 months) were tested in the water maze and open field. Of these, seven superior and seven inferior learners were compared with each other in terms of levels of in vitro short- and long-term potentiation (STP and LTP), and gene expression of choline acetyltransferase (ChAT) as well as of the NMDA-NR2A-C subunits assessed by quantitative RT-PCR. Results revealed that the superior as compared with the inferior learners had higher levels of ChAT mRNA in the striatum. For the superior group, ChAT mRNA was correlated with escape on to the cued platform in the water maze, whereas level o…