Search results for "N-Methyl-D-Aspartate"

Fatigue in SLE: diagnostic and pathogenic impact of anti-N-methyl-D-aspartate receptor (NMDAR) autoantibodies.

2019

ObjectivesWe explored the impact of circulating anti-N-methyl-D-aspartate receptor (NMDAR) antibodies on the severity of fatigue in patients with systemic lupus erythematosus (SLE).MethodsSerum samples of 426 patients with SLE were analysed for the presence of antibodies to the NR2 subunit of the NMDAR. In parallel, the severity of fatigue was determined according to the Fatigue Scale for Motor and Cognitive functions questionnaire. In a subgroup of patients with SLE, the hippocampal volume was correlated with the levels of anti-NR2 antibodies. Isolated immunoglobulin G from patients with anti-NR2 antibodies were used for murine immunohistochemical experiments and functional assays on neuro…

S-Ketamine-Induced NMDA Receptor Blockade during Natural Speech Production and Its Implications for Formal Thought Disorder in Schizophrenia: A Pharm…

2017

Structural and functional changes in the lateral temporal language areas have been related to formal thought disorder (FTD) in schizophrenia. Continuous, natural speech production activates the right lateral temporal lobe in schizophrenia, as opposed to the left in healthy subjects. Positive and negative FTD can be elicited in healthy subjects by glutamatergic NMDA blockade with ketamine. It is unclear whether the glutamate system is related to the reversed hemispheric lateralization during speaking in patients. In a double-blind, crossover, placebo-controlled study, 15 healthy, male, right-handed volunteers overtly described 7 pictures for 3 min each while BOLD signal changes were acquired…

Dose escalating safety study of CNS 5161 HCl, a new neuronal glutamate receptor antagonist (NMDA) for the treatment of neuropathic pain

2007

What is already known about this subject • Despite encouraging effects of N-methyl-D-aspartate (NMDA) receptor antagonists in reducing neuropathic pain of different aetiologies, the clinical use of these agents has been limited by their mainly psychotropic side-effects. • In a recent study in healthy volunteers, CNS 5161, a novel noncompetetive NMDA receptor antagonist, was well tolerated up to a dosage of 2000 µg without psychotropic side-effects. • This is the first study to evaluate the maximal tolerated dosage of CNS 5161 and to gain experience about the analgesic effect of CNS 5161 in patients with different pain syndromes. What this study adds • In patients with neuropathic pain CNS 5…

Apomorphine-Induced Growth Hormone Response Is Attenuated by Ethanol but Not Dextromethorphan

2007

Background: Misuse of alcohol drinking is a major health problem. Alcohol decreases spontaneous growth hormone (GH) secretion, but the mechanism is unclear. The aim of this study was to test whether administration of alcohol (study 1) or a N-methyl d-aspartate (NMDA) receptor antagonist (study 2) attenuates the GH response to pharmacological dopaminergic stimulation. Methods: The 2-session repeated measures design was conducted at the endocrine laboratory at the Department of Psychiatry at the Free University Berlin. Twenty healthy Caucasian males aged 35±10 years without a history of alcohol use disorders were tested using the Apomorphine (APO) challenge test. In study 1, we injected APO (…

Polymorphisms in the N-methyl-D-aspartate receptor 1 and 2B subunits are associated with alcoholism-related traits.

2003

Abstract Background This study examined the hypothesis that allelic variants of the ionotropic glutamatergic N-methyl-D-aspartate receptor (NMDAR) are associated with vulnerability to alcoholism and some related traits. Methods We investigated the silent G2108A and C2664T polymorphisms of the NMDAR1 and the NMDAR2B genes, respectively. The case control study included 367 alcoholic and 335 control subjects of German origin. The family-based study comprised 81 Polish alcoholic patients and their parents using the transmission disequilibrium test. Results The genotype frequencies of the NMDAR1 polymorphism differed significantly between control and alcoholic subjects. This difference was also …

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…

Exposure to gp120 of HIV-1 induces an increased release of arachidonic acid in rat primary neuronal cell culture followed by NMDA receptor-mediated n…

1995

After incubation of highly enriched neurons from rat cerebral cortex with the HIV-1 coat protein gp120 for 18 h, cells showed fragmentation of DNA at internucleosomal linkers followed by NMDA receptor-mediated neurotoxicity. We report that in response to exposure to gp120 cells react with an increased release of arachidonic acid (AA) via activation of phospholipase A2. This process was not inhibited by NMDA receptor antagonists. To investigate the role of AA on the sensitivity of the NMDA receptor towards its agonist, low concentrations of NMDA were co-administered with AA. This condition enhanced the NMDA-mediated cytotoxicity. Administration of mepacrine reduced cytotoxicity caused by gp1…

No association of alcohol dependence with a NMDA-receptor 2B gene variant

2003

Postsynaptic Secretion of BDNF and NT-3 from Hippocampal Neurons Depends on Calcium–Calmodulin Kinase II Signaling and Proceeds via Delayed Fusion Po…

2007

The mammalian neurotrophins (NTs) NGF, BDNF, NT-3, and NT-4 constitute a family of secreted neuronal growth factors. In addition, NTs are implicated in several forms of activity-dependent synaptic plasticity. Although synaptic secretion of NTs has been described, the intracellular signaling cascades that regulate synaptic secretion of NTs are far from being understood. Analysis of NT secretion at the subcellular level is thus required to resolve the role of presynaptic and postsynaptic NT secretion for synaptic plasticity. Here, we transfected cultures of dissociated rat hippocampal neurons with green fluorescent protein-tagged versions of BDNF and NT-3, respectively, and identified NT vesi…

Cannabinoid CB1 receptors regulate neuronal TNF-α effects in experimental autoimmune encephalomyelitis.

2011

Abstract Cannabinoid CB1 receptors (CB1Rs) regulate the neurodegenerative damage of experimental autoimmune encephalomyelitis (EAE) and of multiple sclerosis (MS). The mechanism by which CB1R stimulation exerts protective effects is still unclear. Here we show that pharmacological activation of CB1Rs dampens the tumor necrosis factor α (TNFα)-mediated potentiation of striatal spontaneous glutamate-mediated excitatory postsynaptic currents (EPSCs), which is believed to cogently contribute to the inflammation-induced neurodegenerative damage observed in EAE mice. Furthermore, mice lacking CB1Rs showed a more severe clinical course and, in parallel, exacerbated alterations of sEPSC duration af…