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Focusing on the Emerging Role of Kainate Receptors in the Dorsal Cochlear Nucleus (DCN) and Cerebellum. Int J Mol Sci 2023; 24:ijms24021718. [PMID: 36675230 PMCID: PMC9865595 DOI: 10.3390/ijms24021718] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 12/31/2022] [Accepted: 01/04/2023] [Indexed: 01/17/2023] Open
Abstract
Mammals have a dorsal cochlear nucleus (DCN), which is thought to be a cerebellum-like structure with similar features in terms of structure and microcircuitry to the cerebellum. Both the DCN and cerebellum perform their functions depending on synaptic and neuronal networks mediated by various glutamate receptors. Kainate receptors (KARs) are one class of the glutamate receptor family and are strongly expressed in the hippocampus, the cerebellum, and cerebellum-like structures. The cellular distribution and the potential role of KARs in the hippocampus have been extensively investigated. However, the cellular distribution and the potential role of KARs in cerebellum-like structures, including the DCN and cerebellum, are poorly understood. In this review, we summarize the similarity between the DCN and cerebellum at the levels of structure, circuitry, and cell type as well as the investigations referring to the expression patterns of KARs in the DCN and cerebellum according to previous studies. Recent studies on the role of KARs have shown that KARs mediate a bidirectional modulatory effect at parallel fiber (PF)-Purkinje cell (PC) synapses in the cerebellum, implying insights into their roles in cerebellum-like structures, including the DCN, that remain to be explored in the coming years.
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2
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Kainate receptors in the developing neuronal networks. Neuropharmacology 2021; 195:108585. [PMID: 33910033 DOI: 10.1016/j.neuropharm.2021.108585] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/15/2021] [Accepted: 04/16/2021] [Indexed: 12/14/2022]
Abstract
Kainate receptors (KARs) are highly expressed in the immature brain and have unique developmentally regulated functions that may be important in linking neuronal activity to morphogenesis during activity-dependent fine-tuning of the synaptic connectivity. Altered expression of KARs in the developing neural network leads to changes in glutamatergic connectivity and network excitability, which may lead to long-lasting changes in behaviorally relevant circuitries in the brain. Here, we summarize the current knowledge on physiological and morphogenic functions described for different types of KARs at immature neural circuitries, focusing on their roles in modulating synaptic transmission and plasticity as well as circuit maturation in the rodent hippocampus and amygdala. Finally, we discuss the emerging evidence suggesting that malfunction of KARs in the immature brain may contribute to the pathophysiology underlying developmentally originating neurological disorders.
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3
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Jack A, Hamad MIK, Gonda S, Gralla S, Pahl S, Hollmann M, Wahle P. Development of Cortical Pyramidal Cell and Interneuronal Dendrites: a Role for Kainate Receptor Subunits and NETO1. Mol Neurobiol 2019; 56:4960-4979. [PMID: 30421168 DOI: 10.1007/s12035-018-1414-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 10/25/2018] [Indexed: 12/18/2022]
Abstract
During neuronal development, AMPA receptors (AMPARs) and NMDA receptors (NMDARs) are important for neuronal differentiation. Kainate receptors (KARs) are closely related to AMPARs and involved in the regulation of cortical network activity. However, their role for neurite growth and differentiation of cortical neurons is unclear. Here, we used KAR agonists and overexpression of selected KAR subunits and their auxiliary neuropilin and tolloid-like proteins, NETOs, to investigate their influence on dendritic growth and network activity in organotypic cultures of rat visual cortex. Kainate at 500 nM enhanced network activity and promoted development of dendrites in layer II/III pyramidal cells, but not interneurons. GluK2 overexpression promoted dendritic growth in pyramidal cells and interneurons. GluK2 transfectants were highly active and acted as drivers for network activity. GluK1 and NETO1 specifically promoted dendritic growth of interneurons. Our study provides new insights for the roles of KARs and NETOs in the morphological and physiological development of the visual cortex.
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Affiliation(s)
- Alexander Jack
- Faculty for Biology and Biotechnology ND 6/72, Developmental Neurobiology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Mohammad I K Hamad
- Faculty for Biology and Biotechnology ND 6/72, Developmental Neurobiology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
- Medical Faculty, Neuroanatomy and Molecular Brain Research, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Steffen Gonda
- Faculty for Biology and Biotechnology ND 6/72, Developmental Neurobiology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Sebastian Gralla
- Faculty for Biology and Biotechnology ND 6/72, Developmental Neurobiology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Steffen Pahl
- Faculty of Chemistry and Biochemistry, Biochemistry I-Receptor Biochemistry, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Michael Hollmann
- Faculty of Chemistry and Biochemistry, Biochemistry I-Receptor Biochemistry, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Petra Wahle
- Faculty for Biology and Biotechnology ND 6/72, Developmental Neurobiology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany.
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4
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Orav E, Dowavic I, Huupponen J, Taira T, Lauri SE. NETO1 Regulates Postsynaptic Kainate Receptors in CA3 Interneurons During Circuit Maturation. Mol Neurobiol 2019; 56:7473-7489. [PMID: 31044365 PMCID: PMC6815322 DOI: 10.1007/s12035-019-1612-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 04/15/2019] [Indexed: 01/02/2023]
Abstract
Kainate type ionotropic glutamate receptors (KARs) are expressed in hippocampal interneurons and regulate interneuron excitability and GABAergic transmission. Neuropilin tolloid-like proteins (NETO1 and NETO2) act as KAR auxiliary subunits; however, their significance for various functions of KARs in GABAergic interneurons is not fully understood. Here we show that NETO1, but not NETO2, is necessary for dendritic delivery of KAR subunits and, consequently, for formation of KAR-containing synapses in cultured GABAergic neurons. Accordingly, electrophysiological analysis of neonatal CA3 stratum radiatum interneurons revealed impaired postsynaptic and metabotropic KAR signaling in Neto1 knockouts, while a subpopulation of ionotropic KARs in the somatodendritic compartment remained functional. Loss of NETO1/KAR signaling had no significant effect on development of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-D-aspartate (NMDA)-receptor-mediated glutamatergic transmission in CA3 interneurons, contrasting the synaptogenic role proposed for KARs in principal cells. Furthermore, loss of NETO1 had no effect on excitability and characteristic spontaneous network bursts in the immature CA3 circuitry. However, we find that NETO1 is critical for kainate-dependent modulation of network bursts and GABAergic transmission in the hippocampus already during the first week of life. Our results provide the first description of NETO1-dependent subcellular targeting of KAR subunits in GABAergic neurons and indicate that endogenous NETO1 is required for formation of KAR-containing synapses in interneurons. Since aberrant KAR-mediated excitability is implicated in certain forms of epilepsy, NETO1 represents a potential therapeutic target for treatment of both adult and early life seizures.
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Affiliation(s)
- Ester Orav
- Molecular and Integrative Biosciences Research Program, University of Helsinki, PO Box 65, Viikinkaari 1, 00014, Helsinki, Finland.,HiLife Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Ilona Dowavic
- Molecular and Integrative Biosciences Research Program, University of Helsinki, PO Box 65, Viikinkaari 1, 00014, Helsinki, Finland.,HiLife Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Johanna Huupponen
- Molecular and Integrative Biosciences Research Program, University of Helsinki, PO Box 65, Viikinkaari 1, 00014, Helsinki, Finland.,HiLife Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Tomi Taira
- HiLife Neuroscience Center, University of Helsinki, Helsinki, Finland.,Department of Veterinary Biosciences, University of Helsinki, Helsinki, Finland
| | - Sari E Lauri
- Molecular and Integrative Biosciences Research Program, University of Helsinki, PO Box 65, Viikinkaari 1, 00014, Helsinki, Finland. .,HiLife Neuroscience Center, University of Helsinki, Helsinki, Finland.
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5
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Zinchenko VP, Gaidin SG, Teplov IY, Kosenkov AM. Inhibition of spontaneous synchronous activity of hippocampal neurons by excitation of GABAergic neurons. BIOCHEMISTRY MOSCOW SUPPLEMENT SERIES A-MEMBRANE AND CELL BIOLOGY 2017. [DOI: 10.1134/s1990747817040110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Krawczyk M, Ramani M, Dian J, Florez CM, Mylvaganam S, Brien J, Reynolds J, Kapur B, Zoidl G, Poulter MO, Carlen PL. Hippocampal hyperexcitability in fetal alcohol spectrum disorder: Pathological sharp waves and excitatory/inhibitory synaptic imbalance. Exp Neurol 2016; 280:70-9. [PMID: 26996134 DOI: 10.1016/j.expneurol.2016.03.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Revised: 02/29/2016] [Accepted: 03/13/2016] [Indexed: 01/01/2023]
Abstract
Prenatal alcohol exposure (PAE) can lead to long-lasting neurological alterations that may predispose individuals to seizures and neurobehavioral dysfunction. To date, there exists limited information regarding the underlying pathophysiological mechanisms. The hippocampal CA3 region generates excitatory population activity, called sharp waves (SPWs), that provide an ideal model to study perturbations in neuronal excitability at the network and cellular levels. In the present study, we utilized a mouse model of PAE and used dual extracellular and whole-cell patch-clamp recordings from CA3 hippocampal pyramidal cells to evaluate the effect of 1st trimester-equivalent ethanol exposure (10% v/v) on SPW activity and excitatory/inhibitory balance. We observed that PAE significantly altered in vitro SPW waveforms, with an increased duration and amplitude, when compared to controls. In addition, PAE slices exhibited reduced pharmacological inhibition by the GABA-A receptor antagonist bicuculline (BMI) on SPW activity, and increased population spike paired-pulse ratios, all indicative of network disinhibition within the PAE hippocampus. Evaluation of PAE CA3 pyramidal cell activity associated with SPWs, revealed increased action potential cell firing, which was accompanied by an imbalance of excitatory/inhibitory synaptic drive, shifted in favor of excitation. Moreover, we observed intrinsic changes in CA3 pyramidal activity in PAE animals, including increased burst firing and instantaneous firing rate. This is the first study to provide evidence for hippocampal dysfunction in the ability to maintain network homeostasis and underlying cellular hyperexcitability in a model of PAE. These circuit and cellular level alterations may contribute to the increased propensity for seizures and neurobehavioral dysfunction observed in patients with a history of PAE.
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Affiliation(s)
- Michal Krawczyk
- Division of Fundamental Neurobiology, Toronto Western Research Institute, UHN, Toronto, ON, Canada.
| | - Meera Ramani
- Division of Fundamental Neurobiology, Toronto Western Research Institute, UHN, Toronto, ON, Canada
| | - Josh Dian
- Division of Fundamental Neurobiology, Toronto Western Research Institute, UHN, Toronto, ON, Canada
| | - Carlos M Florez
- Division of Fundamental Neurobiology, Toronto Western Research Institute, UHN, Toronto, ON, Canada
| | - Shanthini Mylvaganam
- Division of Fundamental Neurobiology, Toronto Western Research Institute, UHN, Toronto, ON, Canada
| | - James Brien
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
| | - James Reynolds
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, ON, Canada
| | - Bhushan Kapur
- Division of Clinical Pharmacology & Toxicology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Georg Zoidl
- Department of Biology, York University, Toronto, ON, Canada; Department of Psychology, York University, Toronto, ON, Canada
| | - Michael O Poulter
- Robarts Research Institute and Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | - Peter L Carlen
- Division of Fundamental Neurobiology, Toronto Western Research Institute, UHN, Toronto, ON, Canada; Department of Medicine (Neurology), University of Toronto, Toronto, ON, Canada; Department of Physiology, University of Toronto, Toronto, ON, Canada
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Zhong P, Liu W, Yan Z. Aberrant regulation of synchronous network activity by the attention-deficit/hyperactivity disorder-associated human dopamine D4 receptor variant D4.7 in the prefrontal cortex. J Physiol 2015; 594:135-47. [PMID: 26541360 DOI: 10.1113/jp271317] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/29/2015] [Indexed: 01/28/2023] Open
Abstract
KEY POINTS The hD4.7 variant has been linked to attention-deficit/hyperactivity disorder (ADHD); however, the underlying mechanism is unknown. We found that activation of hD4.7 induced over-suppression of glutamatergic excitatory network bursts and under-suppression of GABAergic inhibitory network bursts in the prefrontal cortex (PFC) circuitry. Methylphenidate, a psychostimulant drug used to treat ADHD, normalized the effects of hD4.7 on synchronous network bursts in PFC pyramidal neurons. The findings of the present study suggest that the aberrant regulation of PFC synchronous network activity by hD4.7 may underlie its involvement in ADHD. A unique feature of the human D4 receptor (hD4 R) gene is the existence of a large number of polymorphisms in exon 3 coding for the third intracellular loop, which consists of a variable number of tandem repeats. The hD4 R variants with long repeats have been linked to attention-deficit/hyperactivity disorder (ADHD); however, the underlying mechanism is unknown. Emerging evidence suggests that selective attention is controlled by the rhythmic synchronization in the prefrontal cortex (PFC) and its connected networks. In the present study, we examined the role of hD4 R variants in regulating PFC synchronous network activity. D4 R knockout mice with viral infection of hD4.4 or hD4.7 in the medial PFC were used. Whole-cell patch-clamp recordings were performed to examine the effects of activating hD4.x on the spontaneous large scale correlated activity in PFC pyramidal neurons. We found that, compared to the normal four-repeat variant hD4.4, the ADHD-linked variant hD4.7 induces more suppression of glutamatergic excitatory network bursts and less suppression of GABAergic inhibitory network bursts in the PFC circuitry. Methylphenidate, a psychostimulant drug used to treat ADHD, normalized the effects of hD4.7 on synchronous network bursts in PFC pyramidal neurons. These results reveal the differential effects of hD4 R variants on the integrated excitability of PFC circuits. It is suggested that the aberrant regulation of PFC network activity by hD4.7 may underlie its involvement in ADHD. The methylphenidate-induced normalization of synaptic circuitry regulation may contribute to its effectiveness in ADHD treatment.
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Affiliation(s)
- Ping Zhong
- Department of Physiology & Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA.,VA Western New York Healthcare System, Buffalo, NY, USA
| | - Wenhua Liu
- Department of Physiology & Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA.,School of Lifescience, Zhaoqing University, Zhaoqing, China
| | - Zhen Yan
- Department of Physiology & Biophysics, State University of New York at Buffalo, School of Medicine and Biomedical Sciences, Buffalo, NY, USA.,VA Western New York Healthcare System, Buffalo, NY, USA
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8
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Imbrosci B, Mittmann T. Alterations in membrane and firing properties of layer 2/3 pyramidal neurons following focal laser lesions in rat visual cortex. Neuroscience 2013; 250:208-21. [PMID: 23845747 DOI: 10.1016/j.neuroscience.2013.06.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 06/27/2013] [Accepted: 06/27/2013] [Indexed: 11/19/2022]
Abstract
Focal cortical injuries are well known to cause changes in function and excitability of the surviving cortical areas but the cellular correlates of these physiological alterations are not fully understood. In the present study we employed a well established ex vivo-in vitro model of focal laser lesions in the rat visual cortex and we studied membrane and firing properties of the surviving layer 2/3 pyramidal neurons. Patch-clamp recordings, performed in the first week post-injury, revealed an increased input resistance, a depolarized spike threshold as well as alterations in the firing pattern of neurons in the cortex ipsilateral to the lesion. Notably, the reported lesion-induced alterations emerged or became more evident when an exciting perfusing solution, known as modified artificial cerebrospinal fluid, was used to increase the ongoing synaptic activity in cortical slices. Conversely, application of glutamatergic or GABAA receptor blockers reduced the observed alterations and GABAB receptor blockers abolished the differences completely. All together the present findings suggest that changes in synaptic receptors function, following focal cortical injuries, can modulate membrane and firing properties of layer 2/3 pyramidal neurons. This previously unknown functional interplay between synaptic and membrane properties may constitute a novel cellular mechanism to explain alterations in neuronal network function and excitability following focal cortical injuries.
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Affiliation(s)
- B Imbrosci
- Institute of Physiology and Pathophysiology, University Medical Center of the Johannes-Gutenberg University Mainz, D-55128 Mainz, Germany.
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9
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Lanore F, Labrousse VF, Szabo Z, Normand E, Blanchet C, Mulle C. Deficits in morphofunctional maturation of hippocampal mossy fiber synapses in a mouse model of intellectual disability. J Neurosci 2012; 32:17882-93. [PMID: 23223307 PMCID: PMC6621665 DOI: 10.1523/jneurosci.2049-12.2012] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Revised: 10/16/2012] [Accepted: 10/18/2012] [Indexed: 01/04/2023] Open
Abstract
The grik2 gene, coding for the kainate receptor subunit GluK2 (formerly GluR6), is associated with autism spectrum disorders and intellectual disability. Here, we tested the hypothesis that GluK2 could play a role in the appropriate maturation of synaptic circuits involved in learning and memory. We show that both the functional and morphological maturation of hippocampal mossy fiber to CA3 pyramidal cell (mf-CA3) synapses is delayed in mice deficient for the GluK2 subunit (GluK2⁻/⁻). In GluK2⁻/⁻ mice this deficit is manifested by a transient reduction in the amplitude of AMPA-EPSCs at a critical time point of postnatal development, whereas the NMDA component is spared. By combining multiple probability peak fluctuation analysis and immunohistochemistry, we have provided evidence that the decreased amplitude reflects a decrease in the quantal size per mf-CA3 synapse and in the number of active synaptic sites. Furthermore, we analyzed the time course of structural maturation of CA3 synapses by confocal imaging of YFP-expressing cells followed by tridimensional (3D) anatomical reconstruction of thorny excrescences and presynaptic boutons. We show that major changes in synaptic structures occur subsequently to the sharp increase in synaptic transmission, and more importantly that the course of structural maturation of synaptic elements is impaired in GluK2⁻/⁻ mice. This study highlights how a mutation in a gene linked to intellectual disability in the human may lead to a transient reduction of synaptic strength during postnatal development, impacting on the proper formation of neural circuits linked to memory.
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MESH Headings
- Animals
- Animals, Outbred Strains
- Disease Models, Animal
- Excitatory Amino Acid Agonists/pharmacology
- Excitatory Postsynaptic Potentials/genetics
- Excitatory Postsynaptic Potentials/physiology
- Intellectual Disability/genetics
- Intellectual Disability/metabolism
- Intellectual Disability/pathology
- Intellectual Disability/physiopathology
- Mice
- Mice, Knockout
- Mossy Fibers, Hippocampal/drug effects
- Mossy Fibers, Hippocampal/growth & development
- Mossy Fibers, Hippocampal/pathology
- Mossy Fibers, Hippocampal/physiopathology
- N-Methylaspartate/pharmacology
- Presynaptic Terminals/pathology
- Receptors, Kainic Acid/agonists
- Receptors, Kainic Acid/genetics
- Receptors, Kainic Acid/physiology
- Synapses/pathology
- alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/pharmacology
- GluK2 Kainate Receptor
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Affiliation(s)
- Frederic Lanore
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, and
- CNRS UMR 5297, F-33000 Bordeaux, France
| | - Virginie F. Labrousse
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, and
- CNRS UMR 5297, F-33000 Bordeaux, France
| | - Zsolt Szabo
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, and
- CNRS UMR 5297, F-33000 Bordeaux, France
| | - Elisabeth Normand
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, and
- CNRS UMR 5297, F-33000 Bordeaux, France
| | - Christophe Blanchet
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, and
- CNRS UMR 5297, F-33000 Bordeaux, France
| | - Christophe Mulle
- Interdisciplinary Institute for Neuroscience, University of Bordeaux, and
- CNRS UMR 5297, F-33000 Bordeaux, France
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10
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Ainsworth M, Lee S, Cunningham MO, Traub RD, Kopell NJ, Whittington MA. Rates and rhythms: a synergistic view of frequency and temporal coding in neuronal networks. Neuron 2012; 75:572-83. [PMID: 22920250 DOI: 10.1016/j.neuron.2012.08.004] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/03/2012] [Indexed: 12/20/2022]
Abstract
In the CNS, activity of individual neurons has a small but quantifiable relationship to sensory representations and motor outputs. Coactivation of a few 10s to 100s of neurons can code sensory inputs and behavioral task performance within psychophysical limits. However, in a sea of sensory inputs and demand for complex motor outputs how is the activity of such small subpopulations of neurons organized? Two theories dominate in this respect: increases in spike rate (rate coding) and sharpening of the coincidence of spiking in active neurons (temporal coding). Both have computational advantages and are far from mutually exclusive. Here, we review evidence for a bias in neuronal circuits toward temporal coding and the coexistence of rate and temporal coding during population rhythm generation. The coincident expression of multiple types of gamma rhythm in sensory cortex suggests a mechanistic substrate for combining rate and temporal codes on the basis of stimulus strength.
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Affiliation(s)
- Matt Ainsworth
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
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11
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Lauri S, Taira T. Kainate receptors in developing presynaptic terminals. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/wmts.3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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12
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Frisardi V, Panza F, Farooqui AA. Late-life depression and Alzheimer's disease: the glutamatergic system inside of this mirror relationship. ACTA ACUST UNITED AC 2011; 67:344-55. [PMID: 21570126 DOI: 10.1016/j.brainresrev.2011.04.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2011] [Revised: 04/17/2011] [Accepted: 04/20/2011] [Indexed: 01/08/2023]
Abstract
Late-life depressive syndromes often arise in the context of predementia, dementia syndromes, and Alzheimer's disease (AD). Conversely, patients with a history of mood disorders are at higher risk of developing cognitive impairment. The high rate of co-occurrence of these two disorders is becoming a major health problem in older subjects for both their epidemiological impact and the negative outcomes in terms of disability and increased mortality. In this perspective, it is possible to speculate on the presence of a mirror relationship between depressive and cognitive disorders in late-life. Indeed, although a causal contribution of genetic, environmental, and social factors is widely recognized in these disorders, the neurobiological links still remain largely unknown. l-glutamic acid and γ-aminobutyric acid are the principal excitatory and inhibitory neurotransmitters in the central nervous system, respectively, and increasing evidence suggests that alterations in this neurotransmitter system may contribute to the neurobiology linking depression and cognitive impairment. In the present review article, we examined the neurobiological bases of the relationship between late-life depressive syndromes and AD, with a particular attention to glutamatergic pathway signalling like a bridge connecting these two conditions. In addition, attempts have been made to explain changes in glutamatergic pathway, depression in older age, and dementia through the analysis of signal transduction mechanisms associated with these disabling disorders.
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Affiliation(s)
- Vincenza Frisardi
- Department of Geriatrics, Center for Aging Brain, Memory Unit, University of Bari, Bari, Italy.
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