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Khan A, Richardson B, Roeder N, Hamilton J, Marion M, Fearby N, White O, Owada Y, Kagawa Y, Thanos PK. The role of fatty acid-binding protein 5 and 7 on locomotor, anxiety and social behavior: Interaction with NMDA signaling. Neurosci Lett 2024; 836:137862. [PMID: 38851448 DOI: 10.1016/j.neulet.2024.137862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 05/22/2024] [Accepted: 06/04/2024] [Indexed: 06/10/2024]
Abstract
The endocannabinoid system has been shown to be a powerful mediator of anxiety, learning and memory, as well as nociception behaviors. Exogenous cannabinoids like delta-9-tetrahydrocannabinol mimic the naturally occurring endogenous cannabinoids found in the mammalian central and peripheral nervous system. The hydrophobic properties of endocannabinoids mean that these psychoactive compounds require help with cellular transport. A family of lipid intracellular carriers called fatty acid-binding proteins (FABPs) can bind to endocannabinoids. Pharmacological inhibition or genetic deletion of FABP subtypes 5 and 7 elevates whole-brain anandamide (AEA) levels, a type of endocannabinoid. This study examined locomotor behavior, anxiety-like behavior, and social behavior in FABP5-/- and FABP7-/- mice. Furthermore, we measured N-methyl-D-aspartate (NMDA) receptor levels in the brain to help identify potential underlying mechanisms related to the behavioral findings. Results showed that both male and female FABP5-/- mice exhibited significantly lower activity when compared with both FABP5/7+/+ (control) and FABP7-/-. For social behavior, male, but not female, FABP5-/- mice spent more time interacting with novel mice compared with controls (FABP5/7+/+) and FABP7-/- mice. No significant difference was found for anxiety-like behavior. Results from the NMDA autoradiography revealed [3H] MK-801 binding to be significantly increased within sub-regions of the striatum in FABP7-/- compared with control. In summary, these results show that FABP5 deficiency plays a significant role in locomotion activity, exploratory behavior, as well as social interaction. Furthermore, FABP7 deficiency is shown to play an important role in NMDA receptor expression, while FABP5 does not.
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Affiliation(s)
- Anas Khan
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States
| | - Brittany Richardson
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States
| | - Nicole Roeder
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States
| | - John Hamilton
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States
| | - Matthew Marion
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States
| | - Nathan Fearby
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States
| | - Olivia White
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States
| | - Yuji Owada
- Department of Organ Anatomy, Graduate School of Medicine, Tohoku University, Seiryo-cho 2-1, Aobaku, Sendai 980-8575, Japan
| | - Yoshiteru Kagawa
- Department of Organ Anatomy, Graduate School of Medicine, Tohoku University, Seiryo-cho 2-1, Aobaku, Sendai 980-8575, Japan
| | - Panayotis K Thanos
- Behavioral Neuropharmacology and Neuroimaging Laboratory on Addictions, Clinical Research Institute on Addictions, Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biosciences, State University of New York at Buffalo, Buffalo, NY, United States; Department of Psychology, State University at Buffalo, Buffalo, NY, United States.
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2
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Keith RE, Wild GA, Keith MJ, Chen D, Pack S, Dumas TC. Individual NMDA receptor GluN2 subunit signaling domains differentially regulate the postnatal maturation of hippocampal excitatory synaptic transmission and plasticity but not dendritic morphology. Synapse 2024; 78:e22292. [PMID: 38813758 PMCID: PMC11141731 DOI: 10.1002/syn.22292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 04/16/2024] [Accepted: 04/30/2024] [Indexed: 05/31/2024]
Abstract
N-methyl-d-aspartate receptors (NMDARs) at hippocampal excitatory synapses undergo a late postnatal shift in subunit composition, from an initial prevalence of GluN2B subunit incorporation to a later predominance of GluN2A. This GluN2B to GluN2A shift alters NMDAR calcium conductance dynamics and intracellular molecular signaling that are individually regulated by distinct GluN2 signaling domains and temporally align with developmental alterations in dendritic and synaptic plasticity. However, the impacts of individual GluN2B to GluN2A signaling domains on neuronal development remain unknown. Ionotropic and intracellular signaling domains of GluN2 subunits were separated by creating chimeric GluN2 subunits that were expressed in two transgenic mouse lines. Western blot and immunoprecipitation revealed that roughly one third of native synaptic NMDARs were replaced by transformed NMDARs without altering total synaptic NMDAR content. Schaffer collateral synaptic strength was transiently increased in acutely prepared hippocampal slices at just over 3 weeks of age in animals overexpressing the GluN2B carboxy terminus. Long-term potentiation (LTP) induction following lower frequency stimulation was regulated by GluN2 ionotropic signaling domains in an age-dependent manner and LTP maintenance was enhanced by overexpression of the GluN2B CTD in mature animals. After higher frequency stimulation, the induction and maintenance of LTP were increased in young adult animals overexpressing the GluN2B ionotropic signaling domains but reduced in juveniles just over 3 weeks of age. Confocal imaging of green fluorescent protein (GFP)- labeled CA1 pyramidal neurons revealed no alterations in dendritic morphology or spine density in mice expressing chimeric GluN2 subunits. These results illustrate how individual GluN2 subunit signaling domains do or do not control physiological and morphological development of hippocampal excitatory neurons and better clarify the neurobiological factors that govern hippocampal maturation. SIGNIFICANCE STATEMENT: A developmental reduction in the magnitude of hippocampal long-term synaptic potentiation (LTP) and a concomitant improvement in spatial maze performance coincide with greater incorporation of GluN2A subunits into synaptic NMDARs. Corroborating our prior discovery that overexpression of GluN2A-type ionotropic signaling domains enables context-based navigation in immature mice, GluN2A-type ionotropic signaling domain overexpression reduces LTP induction threshold and magnitude in immature mice. Also, we previously found that GluN2B carboxy terminal domain (CTD) overexpression enhances long-term spatial memory in mature mice and now report that the GluN2B CTD is associated with greater amplitude of LTP after induction in mature mice. Thus, the late postnatal maturation of context encoding likely relies on a shift toward GluN2A-type ionotropic signaling and a reduction in the threshold to induce LTP while memory consolidation and LTP maintenance are regulated by GluN2B subunit CTD signaling.
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Affiliation(s)
- Rachel E. Keith
- Interdisciplinary Program in Neuroscience, College of Science; George Mason University, Fairfax, VA 22030
| | - Grace A. Wild
- Psychology Department, College of Humanities and Social Sciences; George Mason University, Fairfax, VA 22030
| | - Matthew J. Keith
- Interdisciplinary Program in Neuroscience, College of Science; George Mason University, Fairfax, VA 22030
| | - Diyi Chen
- Interdisciplinary Program in Neuroscience, College of Science; George Mason University, Fairfax, VA 22030
| | | | - Theodore C. Dumas
- Interdisciplinary Program in Neuroscience, College of Science; George Mason University, Fairfax, VA 22030
- Psychology Department, College of Humanities and Social Sciences; George Mason University, Fairfax, VA 22030
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3
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Cum M, Santiago Pérez JA, Wangia E, Lopez N, Wright ES, Iwata RL, Li A, Chambers AR, Padilla-Coreano N. A systematic review and meta-analysis of how social memory is studied. Sci Rep 2024; 14:2221. [PMID: 38278973 PMCID: PMC10817899 DOI: 10.1038/s41598-024-52277-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 01/16/2024] [Indexed: 01/28/2024] Open
Abstract
Social recognition is crucial for survival in social species, and necessary for group living, selective reproduction, pair bonding, and dominance hierarchies. Mice and rats are the most commonly used animal models in social memory research, however current paradigms do not account for the complex social dynamics they exhibit in the wild. To assess the range of social memories being studied, we conducted a systematic analysis of neuroscience articles testing the social memory of mice and rats published within the past two decades and analyzed their methods. Our results show that despite these rodent's rich social memory capabilities, the majority of social recognition papers explore short-term memories and short-term familiarity levels with minimal exposure between subject and familiar stimuli-a narrow type of social memory. We have identified several key areas currently understudied or underrepresented: kin relationships, mates, social ranks, sex variabilities, and the effects of aging. Additionally, reporting on social stimulus variables such as housing history, strain, and age, is limited, which may impede reproducibility. Overall, our data highlight large gaps in the diversity of social memories studied and the effects social variables have on social memory mechanisms.
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Affiliation(s)
- Meghan Cum
- Department of Neuroscience, University of Florida, Gainesville, 32610, USA
| | | | - Erika Wangia
- Department of Neuroscience, University of Florida, Gainesville, 32610, USA
| | - Naeliz Lopez
- Department of Neuroscience, University of Florida, Gainesville, 32610, USA
| | - Elizabeth S Wright
- Department of Neuroscience, University of Florida, Gainesville, 32610, USA
| | - Ryo L Iwata
- Department of Neuroscience, University of Florida, Gainesville, 32610, USA
| | - Albert Li
- Department of Neuroscience, University of Florida, Gainesville, 32610, USA
| | - Amelia R Chambers
- Department of Neuroscience, University of Florida, Gainesville, 32610, USA
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Cum M, Pérez JS, Wangia E, Lopez N, Wright ES, Iwata RL, Li A, Chambers AR, Padilla-Coreano N. Mind the gap: A systematic review and meta-analysis of how social memory is studied. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.20.572606. [PMID: 38187659 PMCID: PMC10769336 DOI: 10.1101/2023.12.20.572606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Social recognition is crucial for survival in social species, and necessary for group living, selective reproduction, pair bonding, and dominance hierarchies. Mice and rats are the most commonly used animal models in social memory research, however current paradigms do not account for the complex social dynamics they exhibit in the wild. To assess the range of social memories being studied, we conducted a systematic analysis of neuroscience articles testing the social memory of mice and rats published within the past two decades and analyzed their methods. Our results show that despite these rodent's rich social memory capabilities, the majority of social recognition papers explore short-term memories and short-term familiarity levels with minimal exposure between subject and familiar stimuli - a narrow type of social memory. We have identified several key areas currently understudied or underrepresented: kin relationships, mates, social ranks, sex variabilities, and the effects of aging. Additionally, reporting on social stimulus variables such as housing history, strain, and age, is limited, which may impede reproducibility. Overall, our data highlight large gaps in the diversity of social memories studied and the effects social variables have on social memory mechanisms.
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Biosca-Brull J, Guardia-Escote L, Blanco J, Basaure P, Cabré M, Sánchez-Santed F, Domingo JL, Colomina MT. Prenatal, but not postnatal exposure to chlorpyrifos affects social behavior of mice and the excitatory-inhibitory balance in a sex-dependent manner. Food Chem Toxicol 2022; 169:113423. [PMID: 36113784 DOI: 10.1016/j.fct.2022.113423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 08/26/2022] [Indexed: 11/17/2022]
Abstract
The balance between excitatory and inhibitory neurotransmitters is essential for proper brain development. An imbalance between these two systems has been associated with neurodevelopmental disorders. On the other hand, literature also associates the massive use of pesticides with the increase of these disorders, with a particular focus on chlorpyrifos (CPF) a world-wide used organophosphate pesticide. This study was aimed at assessing social autistic-like behaviors on mice pre or postnatally exposed to CPF (0 or 1 mg/kg/day), in both sexes. In prenatal exposure, C57BL/6J pregnant mice were exposed to CPF through the diet, between gestational days (GD) 12 and 18, while a positive control group for some autistic behaviors was exposed to valproic acid (VPA) on GD 12 and 13. To assess postnatal exposure, C57BL/6J mice were orally exposed to the vehicle (corn oil) or CPF, from postnatal days (PND) 10-15. Social behavior and gene expression analysis were assessed on PND 45. Results showed social alterations only in males prenatally treated. GABA system was upregulated in CPF-treated females, whereas an increase in both systems was observed in both treated males. These findings suggest that males are more sensitive to prenatal CPF exposure, favoring the sex bias observed in ASD.
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Affiliation(s)
- Judit Biosca-Brull
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Psychology and Research Center for Behavior Assessment (CRAMC), Tarragona, Spain; Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain.
| | - Laia Guardia-Escote
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Psychology and Research Center for Behavior Assessment (CRAMC), Tarragona, Spain
| | - Jordi Blanco
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain; Universitat Rovira i Virgili, Department of Basic Medical Sciences, Reus, Spain
| | - Pia Basaure
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain
| | - Maria Cabré
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Biochemistry and Biotechnology, Tarragona, Spain
| | - Fernando Sánchez-Santed
- Department of Psychology, Health Research Center (CEINSA), Almeria University, 04120, Almeria, Spain
| | - José L Domingo
- Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain
| | - Maria Teresa Colomina
- Universitat Rovira i Virgili, Research Group in Neurobehavior and Health (NEUROLAB), Tarragona, Spain; Universitat Rovira i Virgili, Department of Psychology and Research Center for Behavior Assessment (CRAMC), Tarragona, Spain; Universitat Rovira i Virgili, Laboratory of Toxicology and Environmental Health (TECNATOX), Reus, Spain.
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6
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Keith RE, Ogoe RH, Dumas TC. Behind the scenes: Are latent memories supported by calcium independent plasticity? Hippocampus 2022; 32:73-88. [PMID: 33905147 PMCID: PMC8548406 DOI: 10.1002/hipo.23332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 04/08/2021] [Accepted: 04/11/2021] [Indexed: 02/03/2023]
Abstract
N-methyl-D-aspartate receptors (NMDARs) can be considered to be the de facto "plasticity" receptors in the brain due to their central role in the activity-dependent modification of neuronal morphology and synaptic transmission. Since the 1980s, research on NMDARs has focused on the second messenger properties of calcium and the downstream signaling pathways that mediate alterations in neural form and function. Recently, NMDARs were shown to drive activity-dependent synaptic plasticity without calcium influx. How this "nonionotropic" plasticity occurs in vitro is becoming clearer, but research on its involvement in behavior and cognition is in its infancy. There is a partial overlap in the downstream signaling molecules that are involved in ionotropic and nonionotropic NMDAR-dependent plasticity. Given this, and prior studies of the cognitive impacts of ionotropic NMDAR plasticity, a preliminary model explaining how NMDAR nonionotropic plasticity affects learning and memory can be established. We hypothesize that nonionotropic NMDAR plasticity takes part in latent memory encoding in immature rodents through nonassociative depression of synaptic efficacy, and possibly shrinking of dendritic spines. Further, the late postnatal alteration in NMDAR composition in the hippocampus appears to reduce nonionotropic signaling and remove a restriction on memory retrieval. This framework substantially alters the canonical model of NMDAR involvement in spatial cognition and hippocampal maturation and provides novel and exciting inroads for future studies.
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Affiliation(s)
- Rachel E. Keith
- Interdisciplinary Program in Neuroscience, College of Science, George Mason University, Fairfax, Virginia
| | - Richard H. Ogoe
- Department of Psychology, College of Humanities and Social Sciences, George Mason University, Fairfax, Virginia
| | - Theodore C. Dumas
- Interdisciplinary Program in Neuroscience, College of Science, George Mason University, Fairfax, Virginia,Department of Psychology, College of Humanities and Social Sciences, George Mason University, Fairfax, Virginia
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Developmental Shifts in Amygdala Activity during a High Social Drive State. J Neurosci 2021; 41:9308-9325. [PMID: 34611026 DOI: 10.1523/jneurosci.1414-21.2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/27/2021] [Accepted: 09/20/2021] [Indexed: 12/24/2022] Open
Abstract
Amygdala abnormalities characterize several psychiatric disorders with prominent social deficits and often emerge during adolescence. The basolateral amygdala (BLA) bidirectionally modulates social behavior and has increased sensitivity during adolescence. We tested how an environmentally-driven social state is regulated by the BLA in adults and adolescent male rats. We found that a high social drive state caused by brief social isolation increases age-specific social behaviors and increased BLA neuronal activity. Chemogenetic inactivation of BLA decreased the effect of high social drive on social engagement. High social drive preferentially enhanced BLA activity during social engagement; however, the effect of social opportunity on BLA activity was greater during adolescence. While this identifies a substrate underlying age differences in social drive, we then determined that high social drive increased BLA NMDA GluN2B expression and sensitivity to antagonism increased with age. Further, the effect of a high social drive state on BLA activity during social engagement was diminished by GluN2B blockade in an age-dependent manner. These results demonstrate the necessity of the BLA for environmentally driven social behavior, its sensitivity to social opportunity, and uncover a maturing role for BLA and its GluN2B receptors in social engagement.SIGNIFICANCE STATEMENT Social engagement during adolescence is a key component of healthy development. Social drive provides the impetus for social engagement and abnormalities underlie social symptoms of depression and anxiety. While adolescence is characterized by transitions in social drive and social environment sensitivity, little is known about the neural basis for these changes. We found that amygdala activity is uniquely sensitive to social environment during adolescence compared with adulthood, and is required for expression of heightened social drive. In addition, the neural substrates shift toward NMDA dependence in adulthood. These results are the first to demonstrate a unique neural signature of higher social drive and begin to uncover the underlying factors that heighten social engagement during adolescence.
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Regulation of the NMDA receptor by its cytoplasmic domains: (How) is the tail wagging the dog? Neuropharmacology 2021; 195:108634. [PMID: 34097949 DOI: 10.1016/j.neuropharm.2021.108634] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/20/2021] [Accepted: 05/31/2021] [Indexed: 12/18/2022]
Abstract
Excitatory neurotransmission mediated by N-methyl-d-aspartate receptors (NMDARs) is critical for synapse development, function, and plasticity in the brain. NMDARs are tetra-heteromeric cation-channels that mediate synaptic transmission and plasticity. Extensive human studies show the existence of genetic variants in NMDAR subunits genes (GRIN genes) that are associated with neurodevelopmental and neuropsychiatric disorders, including autism spectrum disorders (ASD), epilepsy (EP), intellectual disability (ID), attention deficit hyperactivity disorder (ADHD), and schizophrenia (SCZ). NMDAR subunits have a unique modular architecture with four semiautonomous domains. Here we focus on the carboxyl terminal domain (CTD), also known as the intracellular C-tail, which varies in length among the glutamate receptor subunits and is the most diverse domain in terms of amino acid sequence. The CTD shows no sequence homology to any known proteins but encodes short docking motifs for intracellular binding proteins and covalent modifications. Our review will discuss the many important functions of the CTD in regulating NMDA membrane and synaptic targeting, stabilization, degradation targeting, allosteric modulation and metabotropic signaling of the receptor. This article is part of the special issue on 'Glutamate Receptors - NMDA Receptors'.
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9
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Acutain MF, Griebler Luft J, Vazquez CA, Popik B, Cercato MC, Epstein A, Salvetti A, Jerusalinsky DA, de Oliveira Alvares L, Baez MV. Reduced Expression of Hippocampal GluN2A-NMDAR Increases Seizure Susceptibility and Causes Deficits in Contextual Memory. Front Neurosci 2021; 15:644100. [PMID: 33897358 PMCID: PMC8064689 DOI: 10.3389/fnins.2021.644100] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 03/08/2021] [Indexed: 12/23/2022] Open
Abstract
N-methyl-D-aspartate receptors are heterotetramers composed of two GluN1 obligatory subunits and two regulatory subunits. In cognitive-related brain structures, GluN2A and GluN2B are the most abundant regulatory subunits, and their expression is subjected to tight regulation. During development, GluN2B expression is characteristic of immature synapses, whereas GluN2A is present in mature ones. This change in expression induces a shift in GluN2A/GluN2B ratio known as developmental switch. Moreover, modifications in this relationship have been associated with learning and memory, as well as different pathologies. In this work, we used a specific shRNA to induce a reduction in GluN2A expression after the developmental switch, both in vitro in primary cultured hippocampal neurons and in vivo in adult male Wistar rats. After in vitro characterization, we performed a cognitive profile and evaluated seizure susceptibility in vivo. Our in vitro results showed that the decrease in the expression of GluN2A changes GluN2A/GluN2B ratio without altering the expression of other regulatory subunits. Moreover, rats expressing the anti-GluN2A shRNA in vivo displayed an impaired contextual fear-conditioning memory. In addition, these animals showed increased seizure susceptibility, in terms of both time and intensity, which led us to conclude that deregulation in GluN2A expression at the hippocampus is associated with seizure susceptibility and learning–memory mechanisms.
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Affiliation(s)
- Maria Florencia Acutain
- Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN, CONICET-UBA), Buenos Aires, Argentina
| | - Jordana Griebler Luft
- Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Cecila Alejandra Vazquez
- Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN, CONICET-UBA), Buenos Aires, Argentina
| | - Bruno Popik
- Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Magalí C Cercato
- Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN, CONICET-UBA), Buenos Aires, Argentina
| | | | - Anna Salvetti
- International Center for Infectiology Research (CIRI), INSERM U1111, CNRS UMR5308, Université de Lyon (UCBL1), Lyon, France
| | - Diana A Jerusalinsky
- Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN, CONICET-UBA), Buenos Aires, Argentina
| | | | - Maria Verónica Baez
- Instituto de Biología Celular y Neurociencia "Prof. E. De Robertis" (IBCN, CONICET-UBA), Buenos Aires, Argentina.,1° U.A. Departamento de Histologia, Embriología, Biologia Celular y Genética, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
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10
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Yang J, Ma Q, Dincheva I, Giza J, Jing D, Marinic T, Milner TA, Rajadhyaksha A, Lee FS, Hempstead BL. SorCS2 is required for social memory and trafficking of the NMDA receptor. Mol Psychiatry 2021; 26:927-940. [PMID: 31988435 DOI: 10.1038/s41380-020-0650-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 11/21/2019] [Accepted: 12/02/2019] [Indexed: 11/09/2022]
Abstract
Social memory processing requires functional CA2 neurons, however the specific mechanisms that regulate their activity are poorly understood. Here, we document that SorCS2, a member of the family of the Vps10 family of sorting receptors, is highly expressed in pyramidal neurons of CA2, as well as ventral CA1, a circuit implicated in social memory. SorCS2 specifically localizes to the postsynaptic density and endosomes within dendritic spines of CA2 neurons. We have discovered that SorCS2 is a selective regulator of NMDA receptor surface trafficking in hippocampal neurons, without altering AMPA receptor trafficking. In addition, SorCS2 regulates dendritic spine density in CA2 neurons where SorCS2 expression is enriched, but not in dorsal CA1 neurons, which normally express very low levels of this protein. To specifically test the role of SorCS2 in behavior, we generated a novel SorCS2-deficient mouse, and identify a significant social memory deficit, with no change in sociability, olfaction, anxiety, or several hippocampal-dependent behaviors. Mutations in sorCS2 have been associated with bipolar disease, schizophrenia, and attention deficient-hyperactivity disorder, and abnormalities in social memory are core components of these neuropsychiatric conditions. Thus, our findings provide a new mechanism for social memory formation, through regulating synaptic receptor trafficking in pyramidal neurons by SorCS2.
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Affiliation(s)
- Jianmin Yang
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710004, PR China. .,Division of Hematology and Medical Oncology, Weill Cornell Medical College, New York, NY, 10065, USA.
| | - Qian Ma
- Division of Hematology and Medical Oncology, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Iva Dincheva
- Department of Psychiatry, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Joanna Giza
- Department of Psychiatry, Weill Cornell Medical College, New York, NY, 10065, USA.,Department of Science, Borough of Manhattan Community College, The City University of New York, 199 Chambers Street N699J, New York, NY, 10007, USA
| | - Deqiang Jing
- Department of Psychiatry, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Tina Marinic
- Division of Hematology and Medical Oncology, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Teresa A Milner
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, 1300 York Avenue, New York, NY, 10065, USA.,Laboratory of Neuroendocrinology, The Rockefeller University, 1230 York Avenue, New York, NY, 10065, USA
| | | | - Francis S Lee
- Department of Psychiatry, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Barbara L Hempstead
- Division of Hematology and Medical Oncology, Weill Cornell Medical College, New York, NY, 10065, USA.
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11
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Autism-like social deficit generated by Dock4 deficiency is rescued by restoration of Rac1 activity and NMDA receptor function. Mol Psychiatry 2021; 26:1505-1519. [PMID: 31388105 PMCID: PMC8159750 DOI: 10.1038/s41380-019-0472-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 06/01/2019] [Accepted: 06/24/2019] [Indexed: 12/20/2022]
Abstract
Genetic studies of autism spectrum disorder (ASD) have revealed multigene variations that converge on synaptic dysfunction. DOCK4, a gene at 7q31.1 that encodes the Rac1 guanine nucleotide exchange factor Dock4, has been identified as a risk gene for ASD and other neuropsychiatric disorders. However, whether and how Dock4 disruption leads to ASD features through a synaptic mechanism remain unexplored. We generated and characterized a line of Dock4 knockout (KO) mice, which intriguingly displayed a series of ASD-like behaviors, including impaired social novelty preference, abnormal isolation-induced pup vocalizations, elevated anxiety, and perturbed object and spatial learning. Mice with conditional deletion of Dock4 in hippocampal CA1 recapitulated social preference deficit in KO mice. Examination in CA1 pyramidal neurons revealed that excitatory synaptic transmission was drastically attenuated in KO mice, accompanied by decreased spine density and synaptic content of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid)- and NMDA (N-methyl-D-aspartate)-type glutamate receptors. Moreover, Dock4 deficiency markedly reduced Rac1 activity in the hippocampus, which resulted in downregulation of global protein synthesis and diminished expression of AMPA and NMDA receptor subunits. Notably, Rac1 replenishment in the hippocampal CA1 of Dock4 KO mice restored excitatory synaptic transmission and corrected impaired social deficits in these mice, and pharmacological activation of NMDA receptors also restored social novelty preference in Dock4 KO mice. Together, our findings uncover a previously unrecognized Dock4-Rac1-dependent mechanism involved in regulating hippocampal excitatory synaptic transmission and social behavior.
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Ferri SL, Pallathra AA, Kim H, Dow HC, Raje P, McMullen M, Bilker WB, Siegel SJ, Abel T, Brodkin ES. Sociability development in mice with cell-specific deletion of the NMDA receptor NR1 subunit gene. GENES BRAIN AND BEHAVIOR 2019; 19:e12624. [PMID: 31721416 DOI: 10.1111/gbb.12624] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 11/06/2019] [Accepted: 11/08/2019] [Indexed: 12/13/2022]
Abstract
Social affiliative behavior is an important component of everyday life in many species and is likely to be disrupted in disabling ways in various neurodevelopmental and neuropsychiatric disorders. Therefore, determining the mechanisms involved in these processes is crucial. A link between N-methyl-d-aspartate (NMDA) receptor function and social behaviors has been clearly established. The cell types in which NMDA receptors are critical for social affiliative behavior, however, remain unclear. Here, we use mice carrying a conditional allele of the NMDA R1 subunit to address this question. Mice bearing a floxed NMDAR1 (NR1) allele were crossed with transgenic calcium/calmodulin-dependent kinase IIα (CaMKIIα)-Cre mice or parvalbumin (PV)-Cre mice targeting postnatal excitatory forebrain or PV-expressing interneurons, respectively, and assessed using the three-chambered Social Approach Test. We found that deletion of NR1 in PV-positive interneurons had no effect on social sniffing, but deletion of NR1 in glutamatergic pyramidal cells resulted in a significant increase in social approach behavior, regardless of age or sex. Therefore, forebrain excitatory neurons expressing NR1 play an important role in regulating social affiliative behavior.
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Affiliation(s)
- Sarah L Ferri
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa
| | - Ashley A Pallathra
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Hyong Kim
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Holly C Dow
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Praachi Raje
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mary McMullen
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Warren B Bilker
- Department of Biostatistics and Epidemiology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Steven J Siegel
- Psychiatry and the Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Ted Abel
- Department of Neuroscience and Pharmacology, Iowa Neuroscience Institute, University of Iowa, Iowa City, Iowa
| | - Edward S Brodkin
- Center for Neurobiology and Behavior, Department of Psychiatry, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
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The Role of the N-Methyl-D-Aspartate Receptors in Social Behavior in Rodents. Int J Mol Sci 2019; 20:ijms20225599. [PMID: 31717513 PMCID: PMC6887971 DOI: 10.3390/ijms20225599] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 10/31/2019] [Accepted: 11/05/2019] [Indexed: 01/09/2023] Open
Abstract
The appropriate display of social behaviors is essential for the well-being, reproductive success and survival of an individual. Deficits in social behavior are associated with impaired N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission. In this review, we describe recent studies using genetically modified mice and pharmacological approaches which link the impaired functioning of the NMDA receptors, especially of the receptor subunits GluN1, GluN2A and GluN2B, to abnormal social behavior. This abnormal social behavior is expressed as impaired social interaction and communication, deficits in social memory, deficits in sexual and maternal behavior, as well as abnormal or heightened aggression. We also describe the positive effects of pharmacological stimulation of the NMDA receptors on these social deficits. Indeed, pharmacological stimulation of the glycine-binding site either by direct stimulation or by elevating the synaptic glycine levels represents a promising strategy for the normalization of genetically-induced, pharmacologically-induced or innate deficits in social behavior. We emphasize on the importance of future studies investigating the role of subunit-selective NMDA receptor ligands on different types of social behavior to provide a better understanding of the underlying mechanisms, which might support the development of selective tools for the optimized treatment of disorders associated with social deficits.
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Gromova KV, Muhia M, Rothammer N, Gee CE, Thies E, Schaefer I, Kress S, Kilimann MW, Shevchuk O, Oertner TG, Kneussel M. Neurobeachin and the Kinesin KIF21B Are Critical for Endocytic Recycling of NMDA Receptors and Regulate Social Behavior. Cell Rep 2019; 23:2705-2717. [PMID: 29847800 DOI: 10.1016/j.celrep.2018.04.112] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 02/20/2018] [Accepted: 04/25/2018] [Indexed: 11/24/2022] Open
Abstract
Autism spectrum disorders (ASDs) are associated with mutations affecting synaptic components, including GluN2B-NMDA receptors (NMDARs) and neurobeachin (NBEA). NBEA participates in biosynthetic pathways to regulate synapse receptor targeting, synaptic function, cognition, and social behavior. However, the role of NBEA-mediated transport in specific trafficking routes is unclear. Here, we highlight an additional function for NBEA in the local delivery and surface re-insertion of synaptic receptors in mouse neurons. NBEA dynamically interacts with Rab4-positive recycling endosomes, transiently enters spines in an activity-dependent manner, and regulates GluN2B-NMDAR recycling. Furthermore, we show that the microtubule growth inhibitor kinesin KIF21B constrains NBEA dynamics and is present in the NBEA-recycling endosome-NMDAR complex. Notably, Kif21b knockout decreases NMDAR surface expression and alters social behavior in mice, consistent with reported social deficits in Nbea mutants. The influence of NBEA-KIF21B interactions on GluN2B-NMDAR local recycling may be relevant to mechanisms underlying ASD etiology.
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Affiliation(s)
- Kira V Gromova
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Mary Muhia
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nicola Rothammer
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christine E Gee
- Department of Synaptic Physiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Edda Thies
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Irina Schaefer
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sabrina Kress
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Manfred W Kilimann
- Department of Molecular Neurobiology, Max-Planck Institute for Experimental Medicine, Göttingen, Germany
| | - Olga Shevchuk
- Cellular Proteomics Research Group, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany; Leibniz Institute for Analytical Sciences, ISAS, Dortmund, Germany
| | - Thomas G Oertner
- Department of Synaptic Physiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Matthias Kneussel
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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Pervolaraki E, Hall SP, Foresteire D, Saito T, Saido TC, Whittington MA, Lever C, Dachtler J. Insoluble Aβ overexpression in an App knock-in mouse model alters microstructure and gamma oscillations in the prefrontal cortex, affecting anxiety-related behaviours. Dis Model Mech 2019; 12:dmm040550. [PMID: 31439589 PMCID: PMC6765200 DOI: 10.1242/dmm.040550] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 08/15/2019] [Indexed: 12/31/2022] Open
Abstract
We studied a new amyloid-beta precursor protein (App) knock-in mouse model of Alzheimer's disease (AppNL-G-F ), containing the Swedish KM670/671NL mutation, the Iberian I716F mutation and the Artic E693G mutation, which generates elevated levels of amyloid beta (Aβ)40 and Aβ42 without the confounds associated with APP overexpression. This enabled us to assess changes in anxiety-related and social behaviours, and neural alterations potentially underlying such changes, driven specifically by Aβ accumulation. AppNL-G-F knock-in mice exhibited subtle deficits in tasks assessing social olfaction, but not in social motivation tasks. In anxiety-assessing tasks, AppNL-G-F knock-in mice exhibited: (1) increased thigmotaxis in the open field (OF), yet; (2) reduced closed-arm, and increased open-arm, time in the elevated plus maze (EPM). Their ostensibly anxiogenic OF profile, yet ostensibly anxiolytic EPM profile, could hint at altered cortical mechanisms affecting decision-making (e.g. 'disinhibition'), rather than simple core deficits in emotional motivation. Consistent with this possibility, alterations in microstructure, glutamatergic-dependent gamma oscillations and glutamatergic gene expression were all observed in the prefrontal cortex, but not the amygdala, of AppNL-G-F knock-in mice. Thus, insoluble Aβ overexpression drives prefrontal cortical alterations, potentially underlying changes in social and anxiety-related behavioural tasks.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
| | - Stephen P Hall
- Hull York Medical School, University of York, Heslington, YO10 5DD, UK
| | - Denise Foresteire
- Department of Psychology, Durham University, South Road, Durham, DH1 3LE, UK
| | - Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
| | | | - Colin Lever
- Department of Psychology, Durham University, South Road, Durham, DH1 3LE, UK
| | - James Dachtler
- Department of Psychology, Durham University, South Road, Durham, DH1 3LE, UK
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Sanders EM, Nyarko-Odoom AO, Zhao K, Nguyen M, Liao HH, Keith M, Pyon J, Kozma A, Sanyal M, McHail DG, Dumas TC. Separate functional properties of NMDARs regulate distinct aspects of spatial cognition. ACTA ACUST UNITED AC 2018; 25:264-272. [PMID: 29764972 PMCID: PMC5959228 DOI: 10.1101/lm.047290.118] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 03/12/2018] [Indexed: 11/25/2022]
Abstract
N-methyl-d-aspartate receptors (NMDARs) at excitatory synapses are central to activity-dependent synaptic plasticity and learning and memory. NMDARs act as ionotropic and metabotropic receptors by elevating postsynaptic calcium concentrations and by direct intracellular protein signaling. In the forebrain, these properties are controlled largely by the auxiliary GluN2 subunits, GluN2A and GluN2B. While calcium conductance through NMDAR channels and intracellular protein signaling make separate contributions to synaptic plasticity, it is not known if these properties individually influence learning and memory. To address this issue, we created chimeric GluN2 subunits containing the amino-terminal domain and transmembrane domains from GluN2A or GluN2B fused to the carboxy-terminal domain of GluN2B (termed ABc) or GluN2A ATD (termed BAc), respectively, and expressed these mutated GluN2 subunits in transgenic mice. Expression was confirmed at the mRNA level and protein subunit translation and translocation into dendrites were observed in forebrain neurons. In the spatial version of the Morris water maze, BAc mice displayed signs of a learning deficit. In contrast, ABc animals performed similarly to wild-types during training, but showed a more direct approach to the goal location during a long-term memory test. There was no effect of ABc or BAc expression in a nonspatial water escape task. Since background expression is predominantly GluN2A in mature animals, the results suggest that spatial learning is more sensitive to manipulations of the amino-terminal domain and transmembrane domains (calcium conductance) and long-term memory is regulated more by the carboxy-terminal domain (intracellular protein signaling).
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Affiliation(s)
- Erin M Sanders
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Akua O Nyarko-Odoom
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Kevin Zhao
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Michael Nguyen
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Hong Hong Liao
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Matthew Keith
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Jane Pyon
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Alyssa Kozma
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Mohima Sanyal
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Daniel G McHail
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA
| | - Theodore C Dumas
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, Virginia 22030, USA.,Psychology Department, George Mason University, Fairfax, Virginia 22030, USA
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Jacobs S, Tsien JZ. Adult forebrain NMDA receptors gate social motivation and social memory. Neurobiol Learn Mem 2016; 138:164-172. [PMID: 27575297 DOI: 10.1016/j.nlm.2016.08.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 08/12/2016] [Accepted: 08/25/2016] [Indexed: 01/13/2023]
Abstract
Motivation to engage in social interaction is critical to ensure normal social behaviors, whereas dysregulation in social motivation can contribute to psychiatric diseases such as schizophrenia, autism, social anxiety disorders and post-traumatic stress disorder (PTSD). While dopamine is well known to regulate motivation, its downstream targets are poorly understood. Given the fact that the dopamine 1 (D1) receptors are often physically coupled with the NMDA receptors, we hypothesize that the NMDA receptor activity in the adult forebrain principal neurons are crucial not only for learning and memory, but also for the proper gating of social motivation. Here, we tested this hypothesis by examining sociability and social memory in inducible forebrain-specific NR1 knockout mice. These mice are ideal for exploring the role of the NR1 subunit in social behavior because the NR1 subunit can be selectively knocked out after the critical developmental period, in which NR1 is required for normal development. We found that the inducible deletion of the NMDA receptors prior to behavioral assays impaired, not only object and social recognition memory tests, but also resulted in profound deficits in social motivation. Mice with ablated NR1 subunits in the forebrain demonstrated significant decreases in sociability compared to their wild type counterparts. These results suggest that in addition to its crucial role in learning and memory, the NMDA receptors in the adult forebrain principal neurons gate social motivation, independent of neuronal development.
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Affiliation(s)
- Stephanie Jacobs
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia at Augusta University, Augusta, GA 30907, USA
| | - Joe Z Tsien
- Brain and Behavior Discovery Institute and Department of Neurology, Medical College of Georgia at Augusta University, Augusta, GA 30907, USA.
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