2,031 results match your criteria ampar

Neural Autoantibodies in Cerebrospinal Fluid and Serum in Clinical High Risk for Psychosis, First-Episode Psychosis, and Healthy Volunteers.

Front Psychiatry 2021 26;12:654602. Epub 2021 Mar 26.

Brain and Mind Centre, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.

The pathophysiological role of neural autoantibodies in acute psychotic disorders is receiving increased attention. However, there is still an ongoing debate, whether predominantly psychotic manifestations of autoimmune encephalitides exist that may remain undetected and, thus, untreated. Furthermore, it is discussed if such conditions can be diagnosed based on serum antibody results or if a reliable diagnosis requires additional cerebrospinal fluids (CSF) results. Read More

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Combination of autophagy and NFE2L2/NRF2 activation as a treatment approach for neuropathic pain.

Autophagy 2021 Apr 9:1-21. Epub 2021 Apr 9.

Department of Anesthesiology, Changzheng Hospital, Naval Medical University, 415 Fengyang Road, Shanghai 200003, China.

Macroautophagy/autophagy, an evolutionarily conserved process, plays an important role in the regulation of immune inflammation and nervous system homeostasis. However, the exact role and mechanism of autophagy in pain is still unclear. Here, we showed that impaired autophagy flux mainly occurred in astrocytes during the maintenance of neuropathic pain. Read More

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Longitudinal CSF Findings in Autoimmune Encephalitis-A Monocentric Cohort Study.

Front Immunol 2021 22;12:646940. Epub 2021 Mar 22.

Department of Neurology, Medical University of Vienna, Vienna, Austria.

Autoimmune encephalitis (AIE) poses a diagnostic challenge due to its heterogeneous clinical presentation, which overlaps with various neurological and psychiatric diseases. During the diagnostic work-up, cerebrospinal fluid (CSF) is routinely obtained, allowing for differential diagnostics as well as for the determination of antibody subclasses and specificities. In this monocentric cohort study, we describe initial and serial CSF findings of 33 patients diagnosed with antibody-associated AIE (LGI1 (n=8), NMDA (n=7), CASPR2 (n=3), IgLON5 (n=3), AMPAR (n=1), GAD65/67 (n=4), Yo (n=3), Ma-1/2 (n=2), CV2 (n=2)). Read More

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Regulation of Synaptic Transmission and Plasticity by Protein Phosphatase 1.

J Neurosci 2021 Apr;41(14):3040-3050

Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, New York 14642

Protein phosphatases, by counteracting protein kinases, regulate the reversible phosphorylation of many substrates involved in synaptic plasticity, a cellular model for learning and memory. A prominent phosphatase regulating synaptic plasticity and neurologic disorders is the serine/threonine protein phosphatase 1 (PP1). PP1 has three isoforms (α, β, and γ, encoded by three different genes), which are regulated by a vast number of interacting subunits that define their enzymatic substrate specificity. Read More

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EphrinB2 and GRIP1 stabilize mushroom spines during denervation-induced homeostatic plasticity.

Cell Rep 2021 Mar;34(13):108923

Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany; Max Planck Institute for Brain Research, Max von Laue Str. 4, 60438 Frankfurt am Main, Germany; Cardio-Pulmonary Institute (CPI), Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany. Electronic address:

Despite decades of work, much remains elusive about molecular events at the interplay between physiological and structural changes underlying neuronal plasticity. Here, we combined repetitive live imaging and expansion microscopy in organotypic brain slice cultures to quantitatively characterize the dynamic changes of the intracellular versus surface pools of GluA2-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) across the different dendritic spine types and the shaft during hippocampal homeostatic plasticity. Mechanistically, we identify ephrinB2 and glutamate receptor interacting protein (GRIP) 1 as mediating AMPAR relocation to the mushroom spine surface following lesion-induced denervation. Read More

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A Role for Transmembrane Protein 16C/Slack Impairment in Excitatory Nociceptive Synaptic Plasticity in the Pathogenesis of Remifentanil-induced Hyperalgesia in Rats.

Neurosci Bull 2021 Mar 29. Epub 2021 Mar 29.

Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China.

Remifentanil is widely used to control intraoperative pain. However, its analgesic effect is limited by the generation of postoperative hyperalgesia. In this study, we investigated whether the impairment of transmembrane protein 16C (TMEM16C)/Slack is required for α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic receptor (AMPAR) activation in remifentanil-induced postoperative hyperalgesia. Read More

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Operation theatre protocol for COVID-19 cases requiring orthopaedic surgery: A workflow without altering the existing infrastructure.

J Clin Orthop Trauma 2021 Jun 20;17:163-168. Epub 2021 Mar 20.

Department of Orthopaedics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, 576104, India.

Introduction: The surge in the number of trauma cases following relaxation of lockdowns in the backdrop of COVID-19 pandemic, has strained the existing infrastructure to cater to these patients and also prevent the spread of infection. Moreover, with the rise of newer strains, the period ahead has to be tread carefully to prevent resurgence of infections. There have been recommendations regarding the ideal setup to operate orthopaedic cases in this pandemic scenario. Read More

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Disruption of long-term depression potentiates latent inhibition: Key role for central nucleus of the amygdala.

Int J Neuropsychopharmacol 2021 Mar 8. Epub 2021 Mar 8.

Department of Psychiatry, Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC Canada.

Background: Latent inhibition (LI) reflects an adaptive form of learning, which is impaired in certain forms of mental illness. Glutamate receptor activity is linked to LI, but the potential role of synaptic plasticity remains unspecified.

Methods: Accordingly, the present study examined the possible role of long-term depression (LTD) in LI induced by prior exposure of rats to an auditory stimulus used subsequently as a conditional stimulus (CS) to signal a pending footshock. Read More

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Missense mutation of Fmr1 results in impaired AMPAR-mediated plasticity and socio-cognitive deficits in mice.

Nat Commun 2021 03 10;12(1):1557. Epub 2021 Mar 10.

Université Côte d'Azur, Inserm, CNRS, IPMC, Valbonne, France.

Fragile X syndrome (FXS) is the most frequent form of inherited intellectual disability and the best-described monogenic cause of autism. CGG-repeat expansion in the FMR1 gene leads to FMR1 silencing, loss-of-expression of the Fragile X Mental Retardation Protein (FMRP), and is a common cause of FXS. Missense mutations in the FMR1 gene were also identified in FXS patients, including the recurrent FMRP-R138Q mutation. Read More

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An optimized CRISPR/Cas9 approach for precise genome editing in neurons.

Elife 2021 Mar 10;10. Epub 2021 Mar 10.

Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.

The efficient knock-in of large DNA fragments to label endogenous proteins remains especially challenging in non-dividing cells such as neurons. We developed argeted nock-n with wo (TKIT) guides as a novel CRISPR/Cas9 based approach for efficient, and precise, genomic knock-in. Through targeting non-coding regions TKIT is resistant to INDEL mutations. Read More

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Clinical variables that help in predicting the presence of autoantibodies in patients with acute encephalitis.

Seizure 2021 Feb 24. Epub 2021 Feb 24.

Department of Neurology, FCM, University of Campinas (UNICAMP), and the Brazilian Institute of Neuroscience and Neurotechnology (BRAINN), Campinas, SP, Brazil. Electronic address:

Objective: To identify clinical variables that could predict the presence of autoantibodies in patients with acute encephalitis.

Methods: An observational, retrospective study from May 2011 to May 2017. Clinical, EEG, brain MRI data, and antibodies against human neuronal antigens (NMDAR, GABAR, AMPAR, LGI1, CASPR2, and GAD) from 158 patients with criteria for possible autoimmune encephalitis were analyzed to create a predictive model for this disease. Read More

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February 2021

A Rare Case of Wobbly, Psychotic Patient with Frozen Eyes - Anti-AMPA Receptor Encephalitis.

Neurol India 2021 Jan-Feb;69(1):149-152

Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru, Karnataka, India.

Background: Anti α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) encephalitis is a rare autoimmune encephalitis. They present with memory, confusion or behavioral changes.

Objective: The aim of this study was to describe unusual clinical features in a patient with AMPAR-associated encephalitis. Read More

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P2X4 receptor in the dorsal horn contributes to BDNF/TrkB and AMPA receptor activation in the pathogenesis of remifentanil-induced postoperative hyperalgesia in rats.

Neurosci Lett 2021 04 24;750:135773. Epub 2021 Feb 24.

Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China. Electronic address:

The mechanism underlying the high incidence of remifentanil-induced postoperative hyperalgesia is unclear. Also, no effective prevention method exists. Inflammatory pain-related studies showed that P2X4 purinergic receptors (P2X4Rs) in the dorsal horn of the spinal cord and dorsal root ganglia are essential for maintaining allodynia caused by inflammation. Read More

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The WD40-Repeat Protein WDR-20 and the Deubiquitinating Enzyme USP-46 Promote Cell Surface Levels of Glutamate Receptors.

J Neurosci 2021 Apr 23;41(14):3082-3093. Epub 2021 Feb 23.

Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, Massachusetts 02111

Reversible modification of AMPA receptors (AMPARs) with ubiquitin regulates receptor levels at synapses and controls synaptic strength. The conserved deubiquitinating enzyme (DUB) ubiquitin-specific protease-46 (USP-46) removes ubiquitin from AMPARs and protects them from degradation in both and mammals. Although DUBs are critical for diverse physiological processes, the mechanisms that regulate DUBs, especially in the nervous system, are not well understood. Read More

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PKN1 Is a Novel Regulator of Hippocampal GluA1 Levels.

Front Synaptic Neurosci 2021 5;13:640495. Epub 2021 Feb 5.

CCB-Biocenter, Institute of Neurobiochemistry, Medical University of Innsbruck, Innsbruck, Austria.

Alterations in the processes that control α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) expression, assembly and trafficking are closely linked to psychiatric and neurodegenerative disorders. We have recently shown that the serine/threonine kinase Protein kinase N1 (PKN1) is a developmentally active regulator of cerebellar synaptic maturation by inhibiting AKT and the neurogenic transcription factor neurogenic differentiation factor-2 (NeuroD2). NeuroD2 is involved in glutamatergic synaptic maturation by regulating expression levels of various synaptic proteins. Read More

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February 2021

Nonselective cation permeation in an AMPA-type glutamate receptor.

Proc Natl Acad Sci U S A 2021 Feb;118(8)

Leibniz Forschungsinstitut für Molekulare Pharmakologie, 13125 Berlin, Germany.

Fast excitatory synaptic transmission in the central nervous system relies on the AMPA-type glutamate receptor (AMPAR). This receptor incorporates a nonselective cation channel, which is opened by the binding of glutamate. Although the open pore structure has recently became available from cryo-electron microscopy (Cryo-EM), the molecular mechanisms governing cation permeability in AMPA receptors are not understood. Read More

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February 2021

Subanesthetic ketamine with an AMPAkine attenuates motor impulsivity in rats.

Behav Pharmacol 2021 Feb 15. Epub 2021 Feb 15.

Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, USA.

The concept of 'impulse control' has its roots in early psychiatry and today has progressed into a well-described, although poorly understood, multidimensional endophenotype underlying many neuropsychiatric disorders (e.g., attention deficit hyperactivity disorder, schizophrenia, substance use disorders). Read More

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February 2021

The p38-MK2 Signaling Axis as a Critical Link Between Inflammation and Synaptic Transmission.

Front Cell Dev Biol 2021 28;9:635636. Epub 2021 Jan 28.

Faculty of Science and Engineering, Department of Life Sciences, Manchester Metropolitan University Manchester, Manchester, United Kingdom.

p38 is a mitogen-activated protein kinase (MAPK), that responds primarily to stress stimuli. p38 has a number of targets for phosphorylation, including MAPK-activated protein kinase 2 (MK2). MK2 primarily functions as a master regulator of RNA-binding proteins, indirectly controlling gene expression at the level of translation. Read More

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January 2021

Selective co-activation of α7- and α4β2-nicotinic acetylcholine receptors reverses beta-amyloid-induced synaptic dysfunction.

J Biol Chem 2021 Feb 8:100402. Epub 2021 Feb 8.

Molecular, Cellular and Integrative Neurosciences Program; Department of Biomedical Sciences, Colorado State University, CO, 80523. Electronic address:

Beta-amyloid (Aβ) has been recognized as an early trigger in the pathogenesis of Alzheimer's disease (AD) leading to synaptic and cognitive impairments. Aβ can alter neuronal signaling through interactions with nicotinic acetylcholine receptors (nAChRs), contributing to synaptic dysfunction in AD. The three major nAChR subtypes in the hippocampus are composed of α7-, α4β2-, and α3β4-nAChRs. Read More

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February 2021

Spinal AMPA receptors: Amenable players in central sensitization for chronic pain therapy?

Channels (Austin) 2021 Dec;15(1):284-297

Department of Sensory Signalling, Bogomoletz Institute of Physiology , Kyiv, Ukraine.

The activity-dependent trafficking of AMPA receptors (AMPAR) mediates synaptic strength and plasticity, while the perturbed trafficking of the receptors of different subunit compositions has been linked to memory impairment and to causing neuropathology. In the spinal cord, nociceptive-induced changes in AMPAR trafficking determine the central sensitization of the dorsal horn (DH): changes in AMPAR subunit composition compromise the balance between synaptic excitation and inhibition, rendering interneurons hyperexcitable to afferent inputs, and promoting Ca influx into the DH neurons, thereby amplifying neuronal hyperexcitability. The DH circuits become over-excitable and carry out aberrant sensory processing; this causes an increase in pain sensation in central sensory pathways, giving rise to chronic pain syndrome. Read More

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December 2021

VER/VEGF receptors regulate AMPA receptor surface levels and glutamatergic behavior.

PLoS Genet 2021 Feb 9;17(2):e1009375. Epub 2021 Feb 9.

Department of Developmental, Molecular, and Chemical Biology, Tufts University School of Medicine, Boston, Massachusetts, United States of America.

Several intracellular trafficking pathways contribute to the regulation of AMPA receptor (AMPAR) levels at synapses and the control of synaptic strength. While much has been learned about these intracellular trafficking pathways, a major challenge is to understand how extracellular factors, such as growth factors, neuropeptides and hormones, impinge on specific AMPAR trafficking pathways to alter synaptic function and behavior. Here, we identify the secreted ligand PVF-1 and its cognate VEGF receptor homologs, VER-1 and VER-4, as regulators of glutamate signaling in C. Read More

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February 2021

Ligand-directed two-step labeling to quantify neuronal glutamate receptor trafficking.

Nat Commun 2021 02 5;12(1):831. Epub 2021 Feb 5.

Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University, Nagoya, 464-8603, Japan.

The regulation of glutamate receptor localization is critical for development and synaptic plasticity in the central nervous system. Conventional biochemical and molecular biological approaches have been widely used to analyze glutamate receptor trafficking, especially for α-amino-3-hydroxy-5-methyl-4-isoxazole-propionate-type glutamate receptors (AMPARs). However, conflicting findings have been reported because of a lack of useful tools for analyzing endogenous AMPARs. Read More

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February 2021

Aberrant development of excitatory circuits to inhibitory neurons in the primary visual cortex after neonatal binocular enucleation.

Sci Rep 2021 Feb 4;11(1):3163. Epub 2021 Feb 4.

Department of Biomedical Engineering, Johns Hopkins University, 379 Miller Res. Bldg, Baltimore, MD, 21205, USA.

The development of GABAergic interneurons is important for the functional maturation of cortical circuits. After migrating into the cortex, GABAergic interneurons start to receive glutamatergic connections from cortical excitatory neurons and thus gradually become integrated into cortical circuits. These glutamatergic connections are mediated by glutamate receptors including AMPA and NMDA receptors and the ratio of AMPA to NMDA receptors decreases during development. Read More

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February 2021

Stress undermines reward-guided cognitive performance through synaptic depression in the lateral habenula.

Neuron 2021 03 2;109(6):947-956.e5. Epub 2021 Feb 2.

The Department of Fundamental Neuroscience, The University of Lausanne, 1005 Lausanne, Switzerland; Inserm, UMR-S 839, 75005 Paris, France. Electronic address:

Weighing alternatives during reward pursuit is a vital cognitive computation that, when disrupted by stress, yields aspects of neuropsychiatric disorders. To examine the neural mechanisms underlying these phenomena, we employed a behavioral task in which mice were confronted by a reward and its omission (i.e. Read More

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Ca -permeable AMPA receptors and their auxiliary subunits in synaptic plasticity and disease.

J Physiol 2021 Feb 3. Epub 2021 Feb 3.

Department of Neuroscience, Physiology and Pharmacology, University College London, Gower Street, London, WC1E 6BT, UK.

AMPA receptors are tetrameric glutamate-gated ion channels that mediate a majority of fast excitatory neurotransmission in the brain. They exist as calcium-impermeable (CI-) and calcium-permeable (CP-) subtypes, the latter of which lacks the GluA2 subunit. CP-AMPARs display an array of distinctive biophysical and pharmacological properties that allow them to be functionally identified. Read More

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February 2021

The Snail transcription factor CES-1 regulates glutamatergic behavior in C. elegans.

PLoS One 2021 2;16(2):e0245587. Epub 2021 Feb 2.

Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, Massachusetts, United States of America.

Regulation of AMPA-type glutamate receptor (AMPAR) expression and function alters synaptic strength and is a major mechanism underlying synaptic plasticity. Although transcription is required for some forms of synaptic plasticity, the transcription factors that regulate AMPA receptor expression and signaling are incompletely understood. Here, we identify the Snail family transcription factor ces-1 in an RNAi screen for conserved transcription factors that regulate glutamatergic behavior in C. Read More

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February 2021

Amygdala-hippocampal innervation modulates stress-induced depressive-like behaviors through AMPA receptors.

Proc Natl Acad Sci U S A 2021 Feb;118(6)

Neuroscience Research Institute and Department of Neurobiology, School of Basic Medical Sciences, Peking University Health Science Center, Key Laboratory for Neuroscience, Ministry of Education/National Health Commission of People's Republic of China, IDG/McGovern Institute for Brain Research at Peking University, 100083 Beijing, People's Republic of China;

Chronic stress is one of the most critical factors in the onset of depressive disorders; hence, environmental factors such as psychosocial stress are commonly used to induce depressive-​like traits in animal models of depression. Ventral CA1 (vCA1) in hippocampus and basal lateral amygdala (BLA) are critical sites during chronic stress-induced alterations in depressive subjects; however, the underlying neural mechanisms remain unclear. Here we employed chronic unpredictable mild stress (CUMS) to model depression in mice and found that the activity of the posterior BLA to vCA1 (pBLA-vCA1) innervation was markedly reduced. Read More

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February 2021

An iPSC-based neural model of sialidosis uncovers glycolytic impairment-causing presynaptic dysfunction and deregulation of Ca dynamics.

Neurobiol Dis 2021 May 29;152:105279. Epub 2021 Jan 29.

Department of Cell Modulation, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan. Electronic address:

Sialidosis is a neuropathic lysosomal storage disease caused by a deficiency in the NEU1 gene-encoding lysosomal neuraminidase and characterized by abnormal accumulation of undigested sialyl-oligoconjugates in systemic organs including brain. Although patients exhibit neurological symptoms, the underlying neuropathological mechanism remains unclear. Here, we generated induced pluripotent stem cells (iPSCs) from skin fibroblasts with sialidosis and induced the differentiation into neural progenitor cells (NPCs) and neurons. Read More

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Structure-Activity Relationship of Neuroactive Steroids, Midazolam, and Perampanel Toward Mitigating Tetramine-Triggered Activity in Murine Hippocampal Neuronal Networks.

Toxicol Sci 2021 Apr;180(2):325-341

Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, Davis, California 95616, USA.

Tetramethylenedisulfotetramine (tetramine or TETS), a potent convulsant, triggers abnormal electrical spike activity (ESA) and synchronous Ca2+ oscillation (SCO) patterns in cultured neuronal networks by blocking gamma-aminobutyric acid (GABAA) receptors. Murine hippocampal neuronal/glial cocultures develop extensive dendritic connectivity between glutamatergic and GABAergic inputs and display two distinct SCO patterns when imaged with the Ca2+ indicator Fluo-4: Low amplitude SCO events (LASE) and High amplitude SCO events (HASE) that are dependent on TTX-sensitive network electrical spike activity (ESA). Acute TETS (3. Read More

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