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Lazaridis I, Crittenden JR, Ahn G, Hirokane K, Yoshida T, Wickersham IR, Mahar A, Skara V, Loftus JH, Parvataneni K, Meletis K, Ting JT, Hueske E, Matsushima A, Graybiel AM. Striosomes Target Nigral Dopamine-Containing Neurons via Direct-D1 and Indirect-D2 Pathways Paralleling Classic Direct-Indirect Basal Ganglia Systems. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.01.596922. [PMID: 38915684 PMCID: PMC11195572 DOI: 10.1101/2024.06.01.596922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Balanced activity of canonical direct D1 and indirect D2 basal ganglia pathways is considered a core requirement for normal movement, and their imbalance is an etiologic factor in movement and neuropsychiatric disorders. We present evidence for a conceptually equivalent pair of direct-D1 and indirect-D2 pathways that arise from striatal projection neurons (SPNs) of the striosome compartment rather than from SPNs of the matrix, as do the canonical pathways. These S-D1 and S-D2 striosomal pathways target substantia nigra dopamine-containing neurons instead of basal ganglia motor output nuclei. They modulate movement oppositely to the modulation by the canonical pathways: S-D1 is inhibitory and S-D2 is excitatory. The S-D1 and S-D2 circuits likely influence motivation for learning and action, complementing and reorienting canonical pathway modulation. A major conceptual reformulation of the classic direct-indirect pathway model of basal ganglia function is needed, as well as reconsideration of the effects of D2-targeting therapeutic drugs.
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Affiliation(s)
- Iakovos Lazaridis
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Jill R. Crittenden
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Gun Ahn
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Kojiro Hirokane
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Tomoko Yoshida
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Ian R. Wickersham
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Ara Mahar
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | | | - Johnny H. Loftus
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Krishna Parvataneni
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | | | - Jonathan T. Ting
- Human Cell Types Dept, Allen Institute for Brain Science, Seattle WA 98109, USA
- Department of Physiology and Biophysics, University of Washington, Seattle WA 98195, USA
| | - Emily Hueske
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Ayano Matsushima
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
| | - Ann M. Graybiel
- McGovern Institute for Brain Research and Department of Brain and Cognitive Sciences
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Giossi C, Bahuguna J, Rubin JE, Verstynen T, Vich C. Arkypallidal neurons in the external globus pallidus can mediate inhibitory control by altering competition in the striatum. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.03.592321. [PMID: 38746308 PMCID: PMC11092778 DOI: 10.1101/2024.05.03.592321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Reactive inhibitory control is crucial for survival. Traditionally, this control in mammals was attributed solely to the hyperdirect pathway, with cortical control signals flowing unidirectionally from the subthalamic nucleus (STN) to basal ganglia output regions. Yet recent findings have put this model into question, suggesting that the STN is assisted in stopping actions through ascending control signals to the striatum mediated by the external globus pallidus (GPe). Here we investigate this suggestion by harnessing a biologically-constrained spiking model of the corticobasal ganglia-thalamic (CBGT) circuit that includes pallidostriatal pathways originating from arkypallidal neurons. Through a series of experiments probing the interaction between three critical inhibitory nodes (the STN, arkypallidal cells, and indirect path-way spiny projection neurons), we find that the GPe acts as a critical mediator of both ascending and descending inhibitory signals in the CBGT circuit. In particular, pallidostriatal pathways regulate this process by weakening the direct pathway dominance of the evidence accumulation process driving decisions, which increases the relative suppressive influence of the indirect pathway on basal ganglia output. These findings delineate how pallidostriatal pathways can facilitate action cancellation by managing the bidirectional flow of information within CBGT circuits.
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Matsuda T, Morigaki R, Hayasawa H, Koyama H, Oda T, Miyake K, Takagi Y. Striatal parvalbumin interneurons are activated in a mouse model of cerebellar dystonia. Dis Model Mech 2024; 17:dmm050338. [PMID: 38616770 PMCID: PMC11128288 DOI: 10.1242/dmm.050338] [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: 06/03/2023] [Accepted: 04/09/2024] [Indexed: 04/16/2024] Open
Abstract
Dystonia is thought to arise from abnormalities in the motor loop of the basal ganglia; however, there is an ongoing debate regarding cerebellar involvement. We adopted an established cerebellar dystonia mouse model by injecting ouabain to examine the contribution of the cerebellum. Initially, we examined whether the entopeduncular nucleus (EPN), substantia nigra pars reticulata (SNr), globus pallidus externus (GPe) and striatal neurons were activated in the model. Next, we examined whether administration of a dopamine D1 receptor agonist and dopamine D2 receptor antagonist or selective ablation of striatal parvalbumin (PV, encoded by Pvalb)-expressing interneurons could modulate the involuntary movements of the mice. The cerebellar dystonia mice had a higher number of cells positive for c-fos (encoded by Fos) in the EPN, SNr and GPe, as well as a higher positive ratio of c-fos in striatal PV interneurons, than those in control mice. Furthermore, systemic administration of combined D1 receptor agonist and D2 receptor antagonist and selective ablation of striatal PV interneurons relieved the involuntary movements of the mice. Abnormalities in the motor loop of the basal ganglia could be crucially involved in cerebellar dystonia, and modulating PV interneurons might provide a novel treatment strategy.
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Affiliation(s)
- Taku Matsuda
- Department of Neurosurgery, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
| | - Ryoma Morigaki
- Department of Neurosurgery, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
- Department of Advanced Brain Research, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
- Parkinson's Disease and Dystonia Research Center, Tokushima University Hospital, Tokushima 770-8503, Japan
| | - Hiroaki Hayasawa
- Department of Neurosurgery, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
| | - Hiroshi Koyama
- Department of Neurosurgery, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
| | - Teruo Oda
- Department of Advanced Brain Research, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
| | - Kazuhisa Miyake
- Department of Neurosurgery, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
| | - Yasushi Takagi
- Department of Neurosurgery, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
- Department of Advanced Brain Research, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503, Japan
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Giossi C, Rubin JE, Gittis A, Verstynen T, Vich C. Rethinking the external globus pallidus and information flow in cortico-basal ganglia-thalamic circuits. Eur J Neurosci 2024. [PMID: 38659055 DOI: 10.1111/ejn.16348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 02/27/2024] [Accepted: 03/19/2024] [Indexed: 04/26/2024]
Abstract
For decades, the external globus pallidus (GPe) has been viewed as a passive way-station in the indirect pathway of the cortico-basal ganglia-thalamic (CBGT) circuit, sandwiched between striatal inputs and basal ganglia outputs. According to this model, one-way descending striatal signals in the indirect pathway amplify the suppression of downstream thalamic nuclei by inhibiting GPe activity. Here, we revisit this assumption, in light of new and emerging work on the cellular complexity, connectivity and functional role of the GPe in behaviour. We show how, according to this new circuit-level logic, the GPe is ideally positioned for relaying ascending and descending control signals within the basal ganglia. Focusing on the problem of inhibitory control, we illustrate how this bidirectional flow of information allows for the integration of reactive and proactive control mechanisms during action selection. Taken together, this new evidence points to the GPe as being a central hub in the CBGT circuit, participating in bidirectional information flow and linking multifaceted control signals to regulate behaviour.
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Affiliation(s)
- Cristina Giossi
- Departament de Ciències Matemàtiques i Informàtica, Universitat de les Illes Balears, Palma, Illes Balears, Spain
- Institute of Applied Computing and Community Code, Universitat de les Illes Balears, Palma, Illes Balears, Spain
| | - Jonathan E Rubin
- Department of Mathematics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Aryn Gittis
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Biology, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Timothy Verstynen
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- Department of Psychology & Neuroscience Institute, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Catalina Vich
- Departament de Ciències Matemàtiques i Informàtica, Universitat de les Illes Balears, Palma, Illes Balears, Spain
- Institute of Applied Computing and Community Code, Universitat de les Illes Balears, Palma, Illes Balears, Spain
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Guilhemsang L, Mallet NP. Arkypallidal neurons in basal ganglia circuits: Unveiling novel pallidostriatal loops? Curr Opin Neurobiol 2024; 84:102814. [PMID: 38016260 DOI: 10.1016/j.conb.2023.102814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/30/2023] [Accepted: 10/31/2023] [Indexed: 11/30/2023]
Abstract
Just over a decade ago, a novel GABAergic input originating from a subpopulation of external globus pallidus neurons known as Arkypallidal and projecting exclusively to the striatum was unveiled. At the single-cell level, these pallidostriatal Arkypallidal projections represent one of the largest extrinsic sources of GABA known to innervate the dorsal striatum. This discovery has sparked new questions regarding their role in striatal information processing, the circuit that recruit these neurons, and their influence on behaviour, especially in the context of action selection vs. inhibition. In this review, we will present the different anatomo-functional organization of Arkypallidal neurons as compared to classic Prototypic neurons, including their unique molecular properties and what is known about their specific input/output synaptic organization. We will further describe recent findings that demonstrate one mode of action of Arkypallidal neurons, which is to convey feedback inhibition to the striatum, and how this mechanism is differentially modulated by both striatal projection pathways. Lastly, we will delve into speculations on their mechanistic contribution to striatal action execution or inhibition.
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Affiliation(s)
- Lise Guilhemsang
- Université de Bordeaux, CNRS, Institut des Maladies Neurodégénératives, F-33000 Bordeaux, France
| | - Nicolas P Mallet
- Université de Bordeaux, CNRS, Institut des Maladies Neurodégénératives, F-33000 Bordeaux, France.
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Nambu A, Chiken S. External segment of the globus pallidus in health and disease: Its interactions with the striatum and subthalamic nucleus. Neurobiol Dis 2024; 190:106362. [PMID: 37992783 DOI: 10.1016/j.nbd.2023.106362] [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: 03/08/2023] [Revised: 11/02/2023] [Accepted: 11/19/2023] [Indexed: 11/24/2023] Open
Abstract
The external segment of the globus pallidus (GPe) has long been considered a homogeneous structure that receives inputs from the striatum and sends processed information to the subthalamic nucleus, composing a relay nucleus of the indirect pathway that contributes to movement suppression. Recent methodological revolution in rodents led to the identification of two distinct cell types in the GPe with different fiber connections. The GPe may be regarded as a dynamic, complex and influential center within the basal ganglia circuitry, rather than a simple relay nucleus. On the other hand, many studies have so far been performed in monkeys to clarify the functions of the basal ganglia in the healthy and diseased states, but have not paid much attention to such classification and functional differences of GPe neurons. In this minireview, we consider the knowledge on the rodent GPe and discuss its impact on the understanding of the basal ganglia circuitry in monkeys.
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Affiliation(s)
- Atsushi Nambu
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan; Department of Physiological Sciences, SOKENDAI, Okazaki, Aichi 444-8585, Japan.
| | - Satomi Chiken
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan; Department of Physiological Sciences, SOKENDAI, Okazaki, Aichi 444-8585, Japan
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Li H, Jin X. Multiple dynamic interactions from basal ganglia direct and indirect pathways mediate action selection. eLife 2023; 12:RP87644. [PMID: 37751468 PMCID: PMC10522336 DOI: 10.7554/elife.87644] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023] Open
Abstract
The basal ganglia are known to be essential for action selection. However, the functional role of basal ganglia direct and indirect pathways in action selection remains unresolved. Here, by employing cell-type-specific neuronal recording and manipulation in mice trained in a choice task, we demonstrate that multiple dynamic interactions from the direct and indirect pathways control the action selection. While the direct pathway regulates the behavioral choice in a linear manner, the indirect pathway exerts a nonlinear inverted-U-shaped control over action selection, depending on the inputs and the network state. We propose a new center (direct)-surround (indirect)-context (indirect) 'Triple-control' functional model of basal ganglia, which can replicate the physiological and behavioral experimental observations that cannot be simply explained by either the traditional 'Go/No-go' or more recent 'Co-activation' model. These findings have important implications on understanding the basal ganglia circuitry and action selection in health and disease.
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Affiliation(s)
- Hao Li
- Molecular Neurobiology Laboratory, The Salk Institute for Biological StudiesLa JollaUnited States
| | - Xin Jin
- Molecular Neurobiology Laboratory, The Salk Institute for Biological StudiesLa JollaUnited States
- Center for Motor Control and Disease, Key Laboratory of Brain Functional Genomics, East China Normal UniversityShanghaiChina
- NYU–ECNU Institute of Brain and Cognitive Science, New York University ShanghaiShanghaiChina
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Li H, Jin X. Multiple dynamic interactions from basal ganglia direct and indirect pathways mediate action selection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.20.533567. [PMID: 36993546 PMCID: PMC10055198 DOI: 10.1101/2023.03.20.533567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
The basal ganglia are known to be essential for action selection. However, the functional role of basal ganglia direct and indirect pathways in action selection remains unresolved. Here by employing cell-type-specific neuronal recording and manipulation in mice trained in a choice task, we demonstrate that multiple dynamic interactions from the direct and indirect pathways control the action selection. While the direct pathway regulates the behavioral choice in a linear manner, the indirect pathway exerts a nonlinear inverted-U-shaped control over action selection, depending on the inputs and the network state. We propose a new center (direct) - surround (indirect) - context (indirect) "Triple-control" functional model of basal ganglia, which can replicate the physiological and behavioral experimental observations that cannot be simply explained by either the traditional "Go/No-go" or more recent "Co-activation" model. These findings have important implications on understanding the basal ganglia circuitry and action selection in health and disease.
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Affiliation(s)
- Hao Li
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Xin Jin
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
- Center for Motor Control and Disease, Key Laboratory of Brain Functional Genomics, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China
- NYU–ECNU Institute of Brain and Cognitive Science, New York University Shanghai, 3663 North Zhongshan Road, Shanghai 200062, China
- Lead Contact
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Jones JA, Higgs MH, Olivares E, Peña J, Wilson CJ. Spontaneous Activity of the Local GABAergic Synaptic Network Causes Irregular Neuronal Firing in the External Globus Pallidus. J Neurosci 2023; 43:1281-1297. [PMID: 36623877 PMCID: PMC9987574 DOI: 10.1523/jneurosci.1969-22.2023] [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: 10/19/2022] [Revised: 12/22/2022] [Accepted: 01/03/2023] [Indexed: 01/11/2023] Open
Abstract
Autonomously firing GABAergic neurons in the external globus pallidus (GPe) form a local synaptic network. In slices, most GPe neurons receive a continuous inhibitory synaptic barrage from 1 or 2 presynaptic GPe neurons. We measured the barrage's effect on the firing rate and regularity of GPe neurons in male and female mice using perforated patch recordings. Silencing the firing of parvalbumin-positive (PV+) GPe neurons by activating genetically expressed Archaerhodopsin current increased the firing rate and regularity of PV- neurons. In contrast, silencing Npas1+ GPe neurons with Archaerhodopsin had insignificant effects on Npas1- neuron firing. Blocking spontaneous GABAergic synaptic input with gabazine reproduced the effects of silencing PV+ neuron firing on the firing rate and regularity of Npas1+ neurons and had similar effects on PV+ neuron firing. To simulate the barrage, we constructed conductance waveforms for dynamic clamp based on experimentally measured inhibitory postsynaptic conductance trains from 1 or 2 unitary local connections. The resulting inhibition replicated the effect on firing seen in the intact active network in the slice. We then increased the number of unitary inputs to match estimates of local network connectivity in vivo As few as 5 unitary inputs produced large increases in firing irregularity. The firing rate was also reduced initially, but PV+ neurons exhibited a slow spike-frequency adaptation that partially restored the rate despite sustained inhibition. We conclude that the irregular firing pattern of GPe neurons in vivo is largely due to the ongoing local inhibitory synaptic barrage produced by the spontaneous firing of other GPe neurons.SIGNIFICANCE STATEMENT Functional roles of local axon collaterals in the external globus pallidus (GPe) have remained elusive because of difficulty in isolating local inhibition from other GABAergic inputs in vivo, and in preserving the autonomous firing of GPe neurons and detecting their spontaneous local inputs in slices. We used perforated patch recordings to detect spontaneous local inputs during rhythmic firing. We found that the autonomous firing of single presynaptic GPe neurons produces inhibitory synaptic barrages that significantly alter the firing regularity of other GPe neurons. Our findings suggest that, although GPe neurons receive input from only a few other GPe neurons, each local connection has a large impact on their firing.
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Affiliation(s)
- James A. Jones
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas at San Antonio, San Antonio, Texas 78249
| | - Matthew H. Higgs
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104
| | - Erick Olivares
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas at San Antonio, San Antonio, Texas 78249
| | - Jacob Peña
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas at San Antonio, San Antonio, Texas 78249
| | - Charles J. Wilson
- Department of Neuroscience, Developmental and Regenerative Biology, University of Texas at San Antonio, San Antonio, Texas 78249
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Padilla-Orozco M, Duhne M, Fuentes-Serrano A, Ortega A, Galarraga E, Bargas J, Lara-González E. Synaptic determinants of cholinergic interneurons hyperactivity during parkinsonism. Front Synaptic Neurosci 2022; 14:945816. [PMID: 36147730 PMCID: PMC9485566 DOI: 10.3389/fnsyn.2022.945816] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 07/21/2022] [Indexed: 11/25/2022] Open
Abstract
Parkinson’s disease is a neurodegenerative ailment generated by the loss of dopamine in the basal ganglia, mainly in the striatum. The disease courses with increased striatal levels of acetylcholine, disrupting the balance among these modulatory transmitters. These modifications disturb the excitatory and inhibitory balance in the striatal circuitry, as reflected in the activity of projection striatal neurons. In addition, changes in the firing pattern of striatal tonically active interneurons during the disease, including cholinergic interneurons (CINs), are being searched. Dopamine-depleted striatal circuits exhibit pathological hyperactivity as compared to controls. One aim of this study was to show how striatal CINs contribute to this hyperactivity. A second aim was to show the contribution of extrinsic synaptic inputs to striatal CINs hyperactivity. Electrophysiological and calcium imaging recordings in Cre-mice allowed us to evaluate the activity of dozens of identified CINs with single-cell resolution in ex vivo brain slices. CINs show hyperactivity with bursts and silences in the dopamine-depleted striatum. We confirmed that the intrinsic differences between the activity of control and dopamine-depleted CINs are one source of their hyperactivity. We also show that a great part of this hyperactivity and firing pattern change is a product of extrinsic synaptic inputs, targeting CINs. Both glutamatergic and GABAergic inputs are essential to sustain hyperactivity. In addition, cholinergic transmission through nicotinic receptors also participates, suggesting that the joint activity of CINs drives the phenomenon; since striatal CINs express nicotinic receptors, not expressed in striatal projection neurons. Therefore, CINs hyperactivity is the result of changes in intrinsic properties and excitatory and inhibitory inputs, in addition to the modification of local circuitry due to cholinergic nicotinic transmission. We conclude that CINs are the main drivers of the pathological hyperactivity present in the striatum that is depleted of dopamine, and this is, in part, a result of extrinsic synaptic inputs. These results show that CINs may be a main therapeutic target to treat Parkinson’s disease by intervening in their synaptic inputs.
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Affiliation(s)
- Montserrat Padilla-Orozco
- División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Mariana Duhne
- División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Department of Neurology, University of California, San Francisco, San Francisco, CA, United States
| | - Alejandra Fuentes-Serrano
- División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Aidán Ortega
- División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Elvira Galarraga
- División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - José Bargas
- División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
- *Correspondence: José Bargas,
| | - Esther Lara-González
- División Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Department of Neuroscience, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- Esther Lara-González,
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Subthalamic nucleus stabilizes movements by reducing neural spike variability in monkey basal ganglia. Nat Commun 2022; 13:2233. [PMID: 35468893 PMCID: PMC9038919 DOI: 10.1038/s41467-022-29750-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 03/22/2022] [Indexed: 02/02/2023] Open
Abstract
The subthalamic nucleus projects to the external and internal pallidum, the modulatory and output nuclei of the basal ganglia, respectively, and plays an indispensable role in controlling voluntary movements. However, the precise mechanism by which the subthalamic nucleus controls pallidal activity and movements remains elusive. Here, we utilize chemogenetics to reversibly reduce neural activity of the motor subregion of the subthalamic nucleus in three macaque monkeys (Macaca fuscata, both sexes) during a reaching task. Systemic administration of chemogenetic ligands prolongs movement time and increases spike train variability in the pallidum, but only slightly affects firing rate modulations. Across-trial analyses reveal that the irregular discharges in the pallidum coincides with prolonged movement time. Reduction of subthalamic activity also induces excessive abnormal movements in the contralateral forelimb, which are preceded by subthalamic and pallidal phasic activity changes. Our results suggest that the subthalamic nucleus stabilizes pallidal spike trains and achieves stable movements. Chemogenetic inactivation of the subthalamic nucleus in monkeys increases spike train variability in the pallidum and prolongs movement time, suggesting its role in stabilizing pallidal spike trains to achieve stable motor control.
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12
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A report on digitised neuronal tracing method to study neurons in their entirety. MethodsX 2022; 9:101715. [PMID: 35592463 PMCID: PMC9111970 DOI: 10.1016/j.mex.2022.101715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 04/21/2022] [Indexed: 11/24/2022] Open
Abstract
Conventional camera lucida (CL) aided neuronal tracing technique for studying neural plasticity is a demanding procedure. Stereo Investigator-Neurolucida enabled neuronal tracing system is not accessible to all researchers. This necessitates alternate simple and less challenging digitised neuronal tracing methods. This report describes a novel digitised neuronal tracing method using widefield microscopy, and its effectiveness is compared with the traditional camera lucida aided neuronal tracing method. Golgi-Cox stained hippocampal cornu ammonis area-3 (CA3) pyramidal neuron photomicrographs were serially captured at a depth of every 2µm in the z-axis by a wide field microscope from the point of appearance to the disappearance. These images were stacked along the axis perpendicular to the image plane to reconstruct the neuron in its entirety, digitally traced and dendritic quantification was performed using open source software. The same neurons were manually traced using camera lucida, and Sholl analysis was done manually to quantify the dendritic arborisation pattern. The dendritic quantification data were not significantly different in both methods. Hence, the technology-enabled, less demanding, and equally accurate neuronal tracing can be adopted instead of manual tracing and analysis of neurons. A simple digitised neuronal tracing method is described. It is fast, rigorous, and comparable to traditional tracing techniques. Helps the researcher to repeatedly probe data to reduce errors.
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13
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Olivares E, Higgs MH, Wilson CJ. Local inhibition in a model of the indirect pathway globus pallidus network slows and deregularizes background firing, but sharpens and synchronizes responses to striatal input. J Comput Neurosci 2022; 50:251-272. [PMID: 35274227 DOI: 10.1007/s10827-022-00814-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/17/2022] [Accepted: 02/24/2022] [Indexed: 11/24/2022]
Abstract
The external segment of globus pallidus (GPe) is a network of oscillatory neurons connected by inhibitory synapses. We studied the intrinsic dynamic and the response to a shared brief inhibitory stimulus in a model GPe network. Individual neurons were simulated using a phase resetting model based on measurements from mouse GPe neurons studied in slices. The neurons showed a broad heterogeneity in their firing rates and in the shapes and sizes of their phase resetting curves. Connectivity in the network was set to match experimental measurements. We generated statistically equivalent neuron heterogeneity in a small-world model, in which 99% of connections were made with near neighbors and 1% at random, and in a model with entirely random connectivity. In both networks, the resting activity was slowed and made more irregular by the local inhibition, but it did not show any periodic pattern. Cross-correlations among neuron pairs were limited to directly connected neurons. When stimulated by a shared inhibitory input, the individual neuron responses separated into two groups: one with a short and stereotyped period of inhibition followed by a transient increase in firing probability, and the other responding with a sustained inhibition. Despite differences in firing rate, the responses of the first group of neurons were of fixed duration and were synchronized across cells.
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Affiliation(s)
- Erick Olivares
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | - Matthew H Higgs
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA
| | - Charles J Wilson
- Department of Biology, University of Texas at San Antonio, San Antonio, TX, USA.
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14
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Abstract
In 1959, E. G. Gray described two different types of synapses in the brain for the first time: symmetric and asymmetric. Later on, symmetric synapses were associated with inhibitory terminals, and asymmetric synapses to excitatory signaling. The balance between these two systems is critical to maintain a correct brain function. Likewise, the modulation of both types of synapses is also important to maintain a healthy equilibrium. Cerebral circuitry responds differently depending on the type of damage and the timeline of the injury. For example, promoting symmetric signaling following ischemic damage is beneficial only during the acute phase; afterwards, it further increases the initial damage. Synapses can be also altered by players not directly related to them; the chronic and long-term neurodegeneration mediated by tau proteins primarily targets asymmetric synapses by decreasing neuronal plasticity and functionality. Dopamine represents the main modulating system within the central nervous system. Indeed, the death of midbrain dopaminergic neurons impairs locomotion, underlying the devastating Parkinson’s disease. Herein, we will review studies on symmetric and asymmetric synapses plasticity after three different stressors: symmetric signaling under acute damage—ischemic stroke; asymmetric signaling under chronic and long-term neurodegeneration—Alzheimer’s disease; symmetric and asymmetric synapses without modulation—Parkinson’s disease.
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15
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Gast R, Gong R, Schmidt H, Meijer HGE, Knösche TR. On the Role of Arkypallidal and Prototypical Neurons for Phase Transitions in the External Pallidum. J Neurosci 2021; 41:6673-6683. [PMID: 34193559 PMCID: PMC8336705 DOI: 10.1523/jneurosci.0094-21.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 04/08/2021] [Accepted: 05/13/2021] [Indexed: 01/10/2023] Open
Abstract
The external pallidum (globus pallidus pars externa [GPe]) plays a central role for basal ganglia functions and dynamics and, consequently, has been included in most computational studies of the basal ganglia. These studies considered the GPe as a homogeneous neural population. However, experimental studies have shown that the GPe contains at least two distinct cell types (prototypical and arkypallidal cells). In this work, we provide in silico insight into how pallidal heterogeneity modulates dynamic regimes inside the GPe and how they affect the GPe response to oscillatory input. We derive a mean-field model of the GPe system from a microscopic spiking neural network of recurrently coupled prototypical and arkypallidal neurons. Using bifurcation analysis, we examine the influence of dopamine-dependent changes of intrapallidal connectivity on the GPe dynamics. We find that increased self-inhibition of prototypical cells can induce oscillations, whereas increased inhibition of prototypical cells by arkypallidal cells leads to the emergence of a bistable regime. Furthermore, we show that oscillatory input to the GPe, arriving from striatum, leads to characteristic patterns of cross-frequency coupling observed at the GPe. Based on these findings, we propose two different hypotheses of how dopamine depletion at the GPe may lead to phase-amplitude coupling between the parkinsonian beta rhythm and a GPe-intrinsic γ rhythm. Finally, we show that these findings generalize to realistic spiking neural networks of sparsely coupled Type I excitable GPe neurons.SIGNIFICANCE STATEMENT Our work provides (1) insight into the theoretical implications of a dichotomous globus pallidus pars externa (GPe) organization, and (2) an exact mean-field model that allows for future investigations of the relationship between GPe spiking activity and local field potential fluctuations. We identify the major phase transitions that the GPe can undergo when subject to static or periodic input and link these phase transitions to the emergence of synchronized oscillations and cross-frequency coupling in the basal ganglia. Because of the close links between our model and experimental findings on the structure and dynamics of prototypical and arkypallidal cells, our results can be used to guide both experimental and computational studies on the role of the GPe for basal ganglia dynamics in health and disease.
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Affiliation(s)
- Richard Gast
- Max Planck Institute for Human Cognitive and Brain Sciences, Brain Networks Group, Leipzig, Germany 04103
| | - Ruxue Gong
- Max Planck Institute for Human Cognitive and Brain Sciences, Brain Networks Group, Leipzig, Germany 04103
| | - Helmut Schmidt
- Max Planck Institute for Human Cognitive and Brain Sciences, Brain Networks Group, Leipzig, Germany 04103
| | - Hil G E Meijer
- Department of Applied Mathematics, Technical Medical Centre, University of Twente, Enschede, The Netherlands 7522 NB
| | - Thomas R Knösche
- Max Planck Institute for Human Cognitive and Brain Sciences, Brain Networks Group, Leipzig, Germany 04103
- Institute for Biomedical Engineering and Informatics, Ilmenau, Germany 98684
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16
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Cui Q, Pamukcu A, Cherian S, Chang IYM, Berceau BL, Xenias HS, Higgs MH, Rajamanickam S, Chen Y, Du X, Zhang Y, McMorrow H, Abecassis ZA, Boca SM, Justice NJ, Wilson CJ, Chan CS. Dissociable Roles of Pallidal Neuron Subtypes in Regulating Motor Patterns. J Neurosci 2021; 41:4036-4059. [PMID: 33731450 PMCID: PMC8176746 DOI: 10.1523/jneurosci.2210-20.2021] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 01/21/2021] [Accepted: 02/20/2021] [Indexed: 01/27/2023] Open
Abstract
We have previously established that PV+ neurons and Npas1+ neurons are distinct neuron classes in the external globus pallidus (GPe): they have different topographical, electrophysiological, circuit, and functional properties. Aside from Foxp2+ neurons, which are a unique subclass within the Npas1+ class, we lack driver lines that effectively capture other GPe neuron subclasses. In this study, we examined the utility of Kcng4-Cre, Npr3-Cre, and Npy2r-Cre mouse lines (both males and females) for the delineation of GPe neuron subtypes. By using these novel driver lines, we have provided the most exhaustive investigation of electrophysiological studies of GPe neuron subtypes to date. Corroborating our prior studies, GPe neurons can be divided into two statistically distinct clusters that map onto PV+ and Npas1+ classes. By combining optogenetics and machine learning-based tracking, we showed that optogenetic perturbation of GPe neuron subtypes generated unique behavioral structures. Our findings further highlighted the dissociable roles of GPe neurons in regulating movement and anxiety-like behavior. We concluded that Npr3+ neurons and Kcng4+ neurons are distinct subclasses of Npas1+ neurons and PV+ neurons, respectively. Finally, by examining local collateral connectivity, we inferred the circuit mechanisms involved in the motor patterns observed with optogenetic perturbations. In summary, by identifying mouse lines that allow for manipulations of GPe neuron subtypes, we created new opportunities for interrogations of cellular and circuit substrates that can be important for motor function and dysfunction.SIGNIFICANCE STATEMENT Within the basal ganglia, the external globus pallidus (GPe) has long been recognized for its involvement in motor control. However, we lacked an understanding of precisely how movement is controlled at the GPe level as a result of its cellular complexity. In this study, by using transgenic and cell-specific approaches, we showed that genetically-defined GPe neuron subtypes have distinct roles in regulating motor patterns. In addition, the in vivo contributions of these neuron subtypes are in part shaped by the local, inhibitory connections within the GPe. In sum, we have established the foundation for future investigations of motor function and disease pathophysiology.
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Affiliation(s)
- Qiaoling Cui
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Arin Pamukcu
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Suraj Cherian
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Isaac Y M Chang
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Brianna L Berceau
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Harry S Xenias
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Matthew H Higgs
- Department of Biology, University of Texas at San Antonio, San Antonio 78249, Texas
| | - Shivakumar Rajamanickam
- Center for Metabolic and degenerative disease, Institute of Molecular Medicine, University of Texas, Houston 77030, Texas
- Department of Integrative Pharmacology, University of Texas, Houston 77030, Texas
| | - Yi Chen
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison 53706, Wisconsin
| | - Xixun Du
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Yu Zhang
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Hayley McMorrow
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Zachary A Abecassis
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
| | - Simina M Boca
- Innovation Center for Biomedical Informatics, Georgetown University Medical Center, Washington 20057, DC
| | - Nicholas J Justice
- Center for Metabolic and degenerative disease, Institute of Molecular Medicine, University of Texas, Houston 77030, Texas
- Department of Integrative Pharmacology, University of Texas, Houston 77030, Texas
| | - Charles J Wilson
- Department of Biology, University of Texas at San Antonio, San Antonio 78249, Texas
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago 60611, Illinois
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17
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Higgs MH, Jones JA, Chan CS, Wilson CJ. Periodic unitary synaptic currents in the mouse globus pallidus during spontaneous firing in slices. J Neurophysiol 2021; 125:1482-1500. [PMID: 33729831 PMCID: PMC8424575 DOI: 10.1152/jn.00071.2021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/11/2021] [Accepted: 03/11/2021] [Indexed: 01/27/2023] Open
Abstract
Neurons in the external globus pallidus (GPe) are autonomous pacemakers, but their spontaneous firing is continually perturbed by synaptic input. Because GPe neurons fire rhythmically in slices, spontaneous inhibitory synaptic currents (IPSCs) should be evident there. We identified periodic series of IPSCs in slices, each corresponding to unitary synaptic currents from one presynaptic cell. Optogenetic stimulation of the striatal indirect pathway axons caused a pause and temporal resetting of the periodic input, confirming that it arose from local neurons subject to striatal inhibition. We determined the firing statistics of the presynaptic neurons from the unitary IPSC statistics and estimated their frequencies, peak amplitudes, and reliabilities. To determine what types of GPe neurons received the spontaneous inhibition, we recorded from genetically labeled parvalbumin (PV) and Npas1-expressing neurons. Both cell types received periodic spontaneous IPSCs with similar frequencies. Optogenetic inhibition of PV neurons reduced the spontaneous IPSC rate in almost all neurons with active unitary inputs, whereas inhibition of Npas1 neurons rarely affected the spontaneous IPSC rate in any neurons. These results suggest that PV neurons provided most of the active unitary inputs to both cell types. Optogenetic pulse stimulation of PV neurons at light levels that can activate cut axons yielded an estimate of connectivity in the fully connected network. The local network is a powerful source of inhibition to both PV and Npas1 neurons, which contributes to irregular firing and may influence the responses to external synaptic inputs.NEW & NOTEWORTHY Brain circuits are often quiet in slices. In the globus pallidus, network activity continues because of the neurons' rhythmic autonomous firing. In this study, synaptic currents generated by the network barrage were measured in single neurons. Unitary synaptic currents arising from single presynaptic neurons were identified by their unique periodicity. Periodic synaptic currents were large and reliable, even at the cell's natural firing rates, but arose from a small number of other globus pallidus neurons.
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Affiliation(s)
- Matthew H Higgs
- Department of Biology, The University of Texas at San Antonio, San Antonio, Texas
| | - James A Jones
- Department of Biology, The University of Texas at San Antonio, San Antonio, Texas
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Charles J Wilson
- Department of Biology, The University of Texas at San Antonio, San Antonio, Texas
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18
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Dong J, Hawes S, Wu J, Le W, Cai H. Connectivity and Functionality of the Globus Pallidus Externa Under Normal Conditions and Parkinson's Disease. Front Neural Circuits 2021; 15:645287. [PMID: 33737869 PMCID: PMC7960779 DOI: 10.3389/fncir.2021.645287] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/05/2021] [Indexed: 12/18/2022] Open
Abstract
The globus pallidus externa (GPe) functions as a central hub in the basal ganglia for processing motor and non-motor information through the creation of complex connections with the other basal ganglia nuclei and brain regions. Recently, with the adoption of sophisticated genetic tools, substantial advances have been made in understanding the distinct molecular, anatomical, electrophysiological, and functional properties of GPe neurons and non-neuronal cells. Impairments in dopamine transmission in the basal ganglia contribute to Parkinson's disease (PD), the most common movement disorder that severely affects the patients' life quality. Altered GPe neuron activity and synaptic connections have also been found in both PD patients and pre-clinical models. In this review, we will summarize the main findings on the composition, connectivity and functionality of different GPe cell populations and the potential GPe-related mechanisms of PD symptoms to better understand the cell type and circuit-specific roles of GPe in both normal and PD conditions.
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Affiliation(s)
- Jie Dong
- Laboratory of Neurogenetics, Transgenic Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, United States
| | - Sarah Hawes
- Laboratory of Neurogenetics, Transgenic Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, United States
| | - Junbing Wu
- Child Health Institute of New Jersey, Rutgers University, New Brunswick, NJ, United States
| | - Weidong Le
- Liaoning Provincial Center for Clinical Research on Neurological Diseases & Liaoning Provincial Key Laboratory for Research on the Pathogenic Mechanisms of Neurological Diseases, The First Affiliated Hospital of Dalian Medical University, Dalian, China
- Medical School of University of Electronic Science and Technology of China, Institute of Neurology, Sichuan Provincial Hospital, Sichuan Academy of Medical Science, Chengdu, China
| | - Huaibin Cai
- Laboratory of Neurogenetics, Transgenic Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, United States
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19
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Horie S, Kiyokage E, Hayashi S, Inoue K, Sohn J, Hioki H, Furuta T, Toida K. Structural basis for noradrenergic regulation of neural circuits in the mouse olfactory bulb. J Comp Neurol 2021; 529:2189-2208. [PMID: 33616936 DOI: 10.1002/cne.25085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 11/19/2020] [Accepted: 11/29/2020] [Indexed: 11/09/2022]
Abstract
Olfactory input is processed in the glomerulus of the main olfactory bulb (OB) and relayed to higher centers in the brain by projection neurons. Conversely, centrifugal inputs from other brain regions project to the OB. We have previously analyzed centrifugal inputs into the OB from several brain regions using single-neuron labeling. In this study, we analyzed the centrifugal noradrenergic (NA) fibers derived from the locus coeruleus (LC), because their projection pathways and synaptic connections in the OB have not been clarified in detail. We analyzed the NA centrifugal projections by single-neuron labeling and immunoelectron microscopy. Individual NA neurons labeled by viral infection were three-dimensionally traced using Neurolucida software to visualize the projection pathway from the LC to the OB. Also, centrifugal NA fibers were visualized using an antibody for noradrenaline transporter (NET). NET immunoreactive (-ir) fibers contained many varicosities and synaptic vesicles. Furthermore, electron tomography demonstrated that NET-ir fibers formed asymmetrical synapses of varied morphology. Although these synapses were present at varicosities, the density of synapses was relatively low throughout the OB. The maximal density of synapses was found in the external plexiform layer; about 17% of all observed varicosities contained synapses. These results strongly suggest that NA-containing fibers in the OB release NA from both varicosities and synapses to influence the activities of OB neurons. The present study provides a morphological basis for olfactory modulation by centrifugal NA fibers derived from the LC.
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Affiliation(s)
- Sawa Horie
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Emi Kiyokage
- Department of Medical Technology, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, Kurashiki, Okayama, Japan
| | - Shuichi Hayashi
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Okayama, Japan
| | - Kanako Inoue
- Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Osaka, Japan
| | - Jaerin Sohn
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
| | - Hiroyuki Hioki
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takahiro Furuta
- Department of Oral Anatomy and Neurobiology, Osaka University Graduate School of Dentistry, Osaka, Japan
| | - Kazunori Toida
- Department of Anatomy, Kawasaki Medical School, Kurashiki, Okayama, Japan.,Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, Osaka, Japan
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20
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Goenner L, Maith O, Koulouri I, Baladron J, Hamker FH. A spiking model of basal ganglia dynamics in stopping behavior supported by arkypallidal neurons. Eur J Neurosci 2021; 53:2296-2321. [PMID: 33316152 DOI: 10.1111/ejn.15082] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 12/01/2020] [Accepted: 12/03/2020] [Indexed: 11/29/2022]
Abstract
The common view that stopping action plans by the basal ganglia is achieved mainly by the subthalamic nucleus alone due to its direct excitatory projection onto the output nuclei of the basal ganglia has been challenged by recent findings. The proposed "pause-then-cancel" model suggests that the subthalamic nucleus provides a rapid stimulus-unspecific "pause" signal, followed by a stop-cue-specific "cancel" signal from striatum-projecting arkypallidal neurons. To determine more precisely the relative contribution of the different basal ganglia nuclei in stopping, we simulated a stop-signal task with a spiking neuron model of the basal ganglia, considering recently discovered connections from the arkypallidal neurons, and cortex-projecting GPe neurons. For the arkypallidal and prototypical GPe neurons, we obtained neuron model parameters by fitting their neuronal responses to published experimental data. Our model replicates findings of stop-signal tasks at neuronal and behavioral levels. We provide evidence for the existence of a stop-related cortical input to the arkypallidal and cortex-projecting GPe neurons such that the stop responses of the subthalamic nucleus, the arkypallidal neurons, and the cortex-projecting GPe neurons complement each other to achieve functional stopping behavior. Particularly, the cortex-projecting GPe neurons may complement the stopping within the basal ganglia caused by the arkypallidal and STN neurons by diminishing cortical go-related processes. Furthermore, we predict effects of lesions on stopping performance and propose that arkypallidal neurons mainly participate in stopping by inhibiting striatal neurons of the indirect rather than the direct pathway.
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Affiliation(s)
- Lorenz Goenner
- Department of Computer Science, Chemnitz University of Technology, Chemnitz, Germany
| | - Oliver Maith
- Department of Computer Science, Chemnitz University of Technology, Chemnitz, Germany
| | - Iliana Koulouri
- Department of Computer Science, Chemnitz University of Technology, Chemnitz, Germany
| | - Javier Baladron
- Department of Computer Science, Chemnitz University of Technology, Chemnitz, Germany
| | - Fred H Hamker
- Department of Computer Science, Chemnitz University of Technology, Chemnitz, Germany
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21
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Aristieta A, Barresi M, Azizpour Lindi S, Barrière G, Courtand G, de la Crompe B, Guilhemsang L, Gauthier S, Fioramonti S, Baufreton J, Mallet NP. A Disynaptic Circuit in the Globus Pallidus Controls Locomotion Inhibition. Curr Biol 2020; 31:707-721.e7. [PMID: 33306949 DOI: 10.1016/j.cub.2020.11.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 11/05/2020] [Accepted: 11/05/2020] [Indexed: 10/22/2022]
Abstract
The basal ganglia (BG) inhibit movements through two independent circuits: the striatal neuron-indirect and the subthalamic nucleus-hyperdirect pathways. These pathways exert opposite effects onto external globus pallidus (GPe) neurons, whose functional importance as a relay has changed drastically with the discovery of two distinct cell types, namely the prototypic and the arkypallidal neurons. However, little is known about the synaptic connectivity scheme of different GPe neurons toward both motor-suppressing pathways, as well as how opposite changes in GPe neuronal activity relate to locomotion inhibition. Here, we optogenetically dissect the input organizations of prototypic and arkypallidal neurons and further define the circuit mechanism and behavioral outcome associated with activation of the indirect or hyperdirect pathways. This work reveals that arkypallidal neurons are part of a novel disynaptic feedback loop differentially recruited by the indirect or hyperdirect pathways and that broadcasts inhibitory control onto locomotion only when arkypallidal neurons increase their activity.
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Affiliation(s)
- Asier Aristieta
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France
| | - Massimo Barresi
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France
| | - Shiva Azizpour Lindi
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France
| | - Grégory Barrière
- Université de Bordeaux, CNRS UMR 5287, INCIA, 33076 Bordeaux, France
| | - Gilles Courtand
- Université de Bordeaux, CNRS UMR 5287, INCIA, 33076 Bordeaux, France
| | - Brice de la Crompe
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France
| | - Lise Guilhemsang
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France
| | - Sophie Gauthier
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France
| | - Stéphanie Fioramonti
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France
| | - Jérôme Baufreton
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France.
| | - Nicolas P Mallet
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33076 Bordeaux, France.
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22
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Pamukcu A, Cui Q, Xenias HS, Berceau BL, Augustine EC, Fan I, Chalasani S, Hantman AW, Lerner TN, Boca SM, Chan CS. Parvalbumin + and Npas1 + Pallidal Neurons Have Distinct Circuit Topology and Function. J Neurosci 2020; 40:7855-7876. [PMID: 32868462 PMCID: PMC7548687 DOI: 10.1523/jneurosci.0361-20.2020] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 06/23/2020] [Accepted: 07/31/2020] [Indexed: 12/19/2022] Open
Abstract
The external globus pallidus (GPe) is a critical node within the basal ganglia circuit. Phasic changes in the activity of GPe neurons during movement and their alterations in Parkinson's disease (PD) argue that the GPe is important in motor control. Parvalbumin-positive (PV+) neurons and Npas1+ neurons are the two principal neuron classes in the GPe. The distinct electrophysiological properties and axonal projection patterns argue that these two neuron classes serve different roles in regulating motor output. However, the causal relationship between GPe neuron classes and movement remains to be established. Here, by using optogenetic approaches in mice (both males and females), we showed that PV+ neurons and Npas1+ neurons promoted and suppressed locomotion, respectively. Moreover, PV+ neurons and Npas1+ neurons are under different synaptic influences from the subthalamic nucleus (STN). Additionally, we found a selective weakening of STN inputs to PV+ neurons in the chronic 6-hydroxydopamine lesion model of PD. This finding reinforces the idea that the reciprocally connected GPe-STN network plays a key role in disease symptomatology and thus provides the basis for future circuit-based therapies.SIGNIFICANCE STATEMENT The external pallidum is a key, yet an understudied component of the basal ganglia. Neural activity in the pallidum goes awry in neurologic diseases, such as Parkinson's disease. While this strongly argues that the pallidum plays a critical role in motor control, it has been difficult to establish the causal relationship between pallidal activity and motor function/dysfunction. This was in part because of the cellular complexity of the pallidum. Here, we showed that the two principal neuron types in the pallidum have opposing roles in motor control. In addition, we described the differences in their synaptic influence. Importantly, our research provides new insights into the cellular and circuit mechanisms that explain the hypokinetic features of Parkinson's disease.
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Affiliation(s)
- Arin Pamukcu
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Qiaoling Cui
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Harry S Xenias
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Brianna L Berceau
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Elizabeth C Augustine
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Isabel Fan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Saivasudha Chalasani
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Adam W Hantman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147
| | - Talia N Lerner
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
| | - Simina M Boca
- Innovation Center for Biomedical Informatics, Georgetown University Medical Center, Washington, DC 20007
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611
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23
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Simmons DV, Higgs MH, Lebby S, Wilson CJ. Indirect pathway control of firing rate and pattern in the substantia nigra pars reticulata. J Neurophysiol 2020; 123:800-814. [PMID: 31940230 DOI: 10.1152/jn.00678.2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Unitary pallido-nigral synaptic currents were measured using optogenetic stimulation, which activated up to three unitary synaptic inputs to each substantia nigra pars reticulata (SNr) cell. Episodic barrages of synaptic conductances were generated based on in vivo firing patterns of globus pallidus pars externa (GPe) cells and applied to SNr cells using conductance clamp. Barrage inputs were compared to continuous step conductances with the same mean. Barrage inputs and steps both slowed SNr neuron firing and produced disinhibition responses seen in peristimulus histograms. Barrages were less effective than steps at producing inhibition and disinhibition responses. Barrages, but not steps, produced irregular firing during the inhibitory response. Phase models of SNr neurons were constructed from their phase-resetting curves. The phase models reproduced the inhibition and disinhibition responses to the same inputs applied to the neurons. The disinhibition response did not require rebound currents but arose from reset of the cells' oscillation. The differences in firing rate and irregularity in response to barrage and step inhibition resulted from the high sensitivity of SNr neurons to inhibition at late phases in their intrinsic oscillation. During step inhibition, cells continued rhythmic firing at a reduced rate. During barrages, brief bouts of intense inhibition stalled the cells' phase evolution late in their cycle, close to firing, and even very brief respites from inhibition rapidly released single action potentials. The SNr cell firing pattern reflected the fine structure of the synaptic barrage from GPe, as well as its onset and offset.NEW & NOTEWORTHY The pallido-nigral pathway connects the striatum to spontaneously active basal ganglia output neurons in the substantia nigra. Each substantia nigra neuron receives powerful inhibitory synaptic connections from a small group of globus pallidus cells and may fire during pauses in pallidal activity. Despite lacking any hyperpolarization-activated rebound currents, they fire quickly to even brief pauses in the pallido-nigral inhibition. The mechanism of their rapid disinhibitory response is explained by features of their phase-resetting curves.
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Affiliation(s)
- DeNard V Simmons
- Department of Biology, University of Texas at San Antonio, San Antonio, Texas
| | - Matthew H Higgs
- Department of Biology, University of Texas at San Antonio, San Antonio, Texas
| | - Sharmon Lebby
- Department of Biology, University of Texas at San Antonio, San Antonio, Texas
| | - Charles J Wilson
- Department of Biology, University of Texas at San Antonio, San Antonio, Texas
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Karube F, Takahashi S, Kobayashi K, Fujiyama F. Motor cortex can directly drive the globus pallidus neurons in a projection neuron type-dependent manner in the rat. eLife 2019; 8:e49511. [PMID: 31711567 PMCID: PMC6863630 DOI: 10.7554/elife.49511] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 10/29/2019] [Indexed: 12/14/2022] Open
Abstract
The basal ganglia are critical for the control of motor behaviors and for reinforcement learning. Here, we demonstrate in rats that primary and secondary motor areas (M1 and M2) make functional synaptic connections in the globus pallidus (GP), not usually thought of as an input site of the basal ganglia. Morphological observation revealed that the density of axonal boutons from motor cortices in the GP was 47% and 78% of that in the subthalamic nucleus (STN) from M1 and M2, respectively. Cortical excitation of GP neurons was comparable to that of STN neurons in slice preparations. FoxP2-expressing arkypallidal neurons were preferentially innervated by the motor cortex. The connection probability of cortico-pallidal innervation was higher for M2 than M1. These results suggest that cortico-pallidal innervation is an additional excitatory input to the basal ganglia, and that it can affect behaviors via the cortex-basal ganglia-thalamus motor loop.
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Affiliation(s)
- Fuyuki Karube
- Laboratory of Neural Circuitry, Graduate School of Brain ScienceDoshisha UniversityKyotanabeJapan
| | - Susumu Takahashi
- Laboratory of Neural Circuitry, Graduate School of Brain ScienceDoshisha UniversityKyotanabeJapan
- Laboratory of Cognitive and Behavioral Neuroscience, Graduate School of Brain ScienceDoshisha UniversityKyotanabeJapan
| | - Kenta Kobayashi
- Section of Viral Vector DevelopmentNational Institute for Physiological SciencesOkazakiJapan
| | - Fumino Fujiyama
- Laboratory of Neural Circuitry, Graduate School of Brain ScienceDoshisha UniversityKyotanabeJapan
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Cellular and Synaptic Dysfunctions in Parkinson's Disease: Stepping out of the Striatum. Cells 2019; 8:cells8091005. [PMID: 31470672 PMCID: PMC6769933 DOI: 10.3390/cells8091005] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/28/2019] [Accepted: 08/29/2019] [Indexed: 12/30/2022] Open
Abstract
The basal ganglia (BG) are a collection of interconnected subcortical nuclei that participate in a great variety of functions, ranging from motor programming and execution to procedural learning, cognition, and emotions. This network is also the region primarily affected by the degeneration of midbrain dopaminergic neurons localized in the substantia nigra pars compacta (SNc). This degeneration causes cellular and synaptic dysfunctions in the BG network, which are responsible for the appearance of the motor symptoms of Parkinson’s disease. Dopamine (DA) modulation and the consequences of its loss on the striatal microcircuit have been extensively studied, and because of the discrete nature of DA innervation of other BG nuclei, its action outside the striatum has been considered negligible. However, there is a growing body of evidence supporting functional extrastriatal DA modulation of both cellular excitability and synaptic transmission. In this review, the functional relevance of DA modulation outside the striatum in both normal and pathological conditions will be discussed.
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26
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Rubin JE. Computational models of basal ganglia dysfunction: the dynamics is in the details. Curr Opin Neurobiol 2017; 46:127-135. [PMID: 28888856 DOI: 10.1016/j.conb.2017.08.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 08/22/2017] [Indexed: 12/18/2022]
Abstract
The development, simulation, and analysis of mathematical models offer helpful tools for integrating experimental findings and exploring or suggesting possible explanatory mechanisms. As models relating to basal ganglia dysfunction have proliferated, however, there has not always been consistency among their findings. This work points out several ways in which biological details, relating to ionic currents and synaptic pathways, can influence the dynamics of models of the basal ganglia under parkinsonian conditions and hence may be important for inclusion in models. It also suggests some additional useful directions for future modeling studies relating to basal ganglia dysfunction.
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Affiliation(s)
- Jonathan E Rubin
- Department of Mathematics and Center for the Neural Basis of Cognition, University of Pittsburgh, 301 Thackeray Hall, Pittsburgh, PA 15260, USA.
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27
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Npas1+ Pallidal Neurons Target Striatal Projection Neurons. J Neurosci 2017; 36:5472-88. [PMID: 27194328 DOI: 10.1523/jneurosci.1720-15.2016] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 04/03/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Compelling evidence demonstrates that the external globus pallidus (GPe) plays a key role in processing sensorimotor information. An anatomical projection from the GPe to the dorsal striatum has been described for decades. However, the cellular target and functional impact of this projection remain unknown. Using cell-specific transgenic mice, modern monosynaptic tracing techniques, and optogenetics-based mapping, we discovered that GPe neurons provide inhibitory inputs to direct and indirect pathway striatal projection neurons (SPNs). Our results indicate that the GPe input to SPNs arises primarily from Npas1-expressing neurons and is strengthened in a chronic Parkinson's disease (PD) model. Alterations of the GPe-SPN input in a PD model argue for the critical position of this connection in regulating basal ganglia motor output and PD symptomatology. Finally, chemogenetic activation of Npas1-expressing GPe neurons suppresses motor output, arguing that strengthening of the GPe-SPN connection is maladaptive and may underlie the hypokinetic symptoms in PD. SIGNIFICANCE STATEMENT An anatomical projection from the pallidum to the striatum has been described for decades, but little is known about its connectivity pattern. The authors dissect the presynaptic and postsynaptic neurons involved in this projection, and show its cell-specific remodeling and strengthening in parkinsonian mice. Chemogenetic activation of Npas1(+) pallidal neurons that give rise to the principal pallidostriatal projection increases the time that the mice spend motionless. This argues that maladaptive strengthening of this connection underlies the paucity of volitional movements, which is a hallmark of Parkinson's disease.
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Pallidostriatal Projections Promote β Oscillations in a Dopamine-Depleted Biophysical Network Model. J Neurosci 2017; 36:5556-71. [PMID: 27194335 DOI: 10.1523/jneurosci.0339-16.2016] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/12/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED In the basal ganglia, focused rhythmicity is an important feature of network activity at certain stages of motor processing. In disease, however, the basal ganglia develop amplified rhythmicity. Here, we demonstrate how the cellular architecture and network dynamics of an inhibitory loop in the basal ganglia yield exaggerated synchrony and locking to β oscillations, specifically in the dopamine-depleted state. A key component of this loop is the pallidostriatal pathway, a well-characterized anatomical projection whose function has long remained obscure. We present a synaptic characterization of this pathway in mice and incorporate these data into a computational model that we use to investigate its influence over striatal activity under simulated healthy and dopamine-depleted conditions. Our model predicts that the pallidostriatal pathway influences striatal output preferentially during periods of synchronized activity within GPe. We show that, under dopamine-depleted conditions, this effect becomes a key component of a positive feedback loop between the GPe and striatum that promotes synchronization and rhythmicity. Our results generate novel predictions about the role of the pallidostriatal pathway in shaping basal ganglia activity in health and disease. SIGNIFICANCE STATEMENT This work demonstrates that functional connections from the globus pallidus externa (GPe) to striatum are substantially stronger onto fast-spiking interneurons (FSIs) than onto medium spiny neurons. Our circuit model suggests that when GPe spikes are synchronous, this pallidostriatal pathway causes synchronous FSI activity pauses, which allow a transient window of disinhibition for medium spiny neurons. In simulated dopamine-depletion, this GPe-FSI activity is necessary for the emergence of strong synchronization and the amplification and propagation of β oscillations, which are a hallmark of parkinsonian circuit dysfunction. These results suggest that GPe may play a central role in propagating abnormal circuit activity to striatum, which in turn projects to downstream basal ganglia structures. These findings warrant further exploration of GPe as a target for interventions for Parkinson's disease.
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29
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Mizutani K, Takahashi S, Okamoto S, Karube F, Fujiyama F. Substance P effects exclusively on prototypic neurons in mouse globus pallidus. Brain Struct Funct 2017; 222:4089-4110. [DOI: 10.1007/s00429-017-1453-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 05/30/2017] [Indexed: 12/22/2022]
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30
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Schwab BC, van Wezel RJA, van Gils SA. Sparse pallidal connections shape synchrony in a network model of the basal ganglia. Eur J Neurosci 2016; 45:1000-1012. [PMID: 27350120 DOI: 10.1111/ejn.13324] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/23/2016] [Accepted: 06/24/2016] [Indexed: 01/15/2023]
Abstract
Neural synchrony in the basal ganglia, especially in the beta frequency band (13-30 Hz), is a hallmark of Parkinson's disease and considered as antikinetic. In contrast, the healthy basal ganglia show low levels of synchrony. It is currently unknown where synchrony and oscillations arise in the parkinsonian brain and how they are transmitted through the basal ganglia, as well as what makes them dependent on dopamine. The external part of the globus pallidus has recently been identified as a hub nucleus in the basal ganglia, possessing intrinsic inhibitory connections and possibly also gap junctions. In this study, we show that in a conductance-based network model of the basal ganglia, the combination of sparse, high-conductance inhibitory synapses and sparse, low-conductance gap junctions in the external part of the globus pallidus could effectively desynchronize the whole network. However, when gap junction coupling became strong enough, the effect was impeded and activity synchronized. In particular, sustained periods of beta coherence occurred between some neuron pairs. As gap junctions can change their conductance with the dopamine level, we suggest pallidal gap junction coupling as a mechanism contributing to the development of beta synchrony in the parkinsonian basal ganglia.
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Affiliation(s)
- Bettina C Schwab
- Applied Analysis, MIRA Institute of Technical Medicine and Biomedical Technology, University of Twente, 7500 AE, Enschede, The Netherlands.,Biomedical Signals and and Systems, MIRA Institute of Technical Medicine and Biomedical Technology, University of Twente, Enschede, The Netherlands
| | - Richard J A van Wezel
- Biomedical Signals and and Systems, MIRA Institute of Technical Medicine and Biomedical Technology, University of Twente, Enschede, The Netherlands.,Biophysics, Donders Institute for Brain, Cognition and Behavior, Radboud University, Nijmegen, The Netherlands
| | - Stephan A van Gils
- Applied Analysis, MIRA Institute of Technical Medicine and Biomedical Technology, University of Twente, 7500 AE, Enschede, The Netherlands
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31
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Saunders A, Huang KW, Sabatini BL. Globus Pallidus Externus Neurons Expressing parvalbumin Interconnect the Subthalamic Nucleus and Striatal Interneurons. PLoS One 2016; 11:e0149798. [PMID: 26905595 PMCID: PMC4764347 DOI: 10.1371/journal.pone.0149798] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 02/04/2016] [Indexed: 01/24/2023] Open
Abstract
The globus pallidus externus (GP) is a nucleus of the basal ganglia (BG), containing GABAergic projection neurons that arborize widely throughout the BG, thalamus and cortex. Ongoing work seeks to map axonal projection patterns from GP cell types, as defined by their electrophysiological and molecular properties. Here we use transgenic mice and recombinant viruses to characterize parvalbumin expressing (PV+) GP neurons within the BG circuit. We confirm that PV+ neurons 1) make up ~40% of the GP neurons 2) exhibit fast-firing spontaneous activity and 3) provide the major axonal arborization to the STN and substantia nigra reticulata/compacta (SNr/c). PV+ neurons also innervate the striatum. Retrograde labeling identifies ~17% of pallidostriatal neurons as PV+, at least a subset of which also innervate the STN and SNr. Optogenetic experiments in acute brain slices demonstrate that the PV+ pallidostriatal axons make potent inhibitory synapses on low threshold spiking (LTS) and fast-spiking interneurons (FS) in the striatum, but rarely on spiny projection neurons (SPNs). Thus PV+ GP neurons are synaptically positioned to directly coordinate activity between BG input nuclei, the striatum and STN, and thalamic-output from the SNr.
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Affiliation(s)
- Arpiar Saunders
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Kee Wui Huang
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Bernardo Luis Sabatini
- Department of Neurobiology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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