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Wongmassang W, Hasegawa T, Chiken S, Nambu A. Weakly correlated activity of pallidal neurons in behaving monkeys. Eur J Neurosci 2020; 53:2178-2191. [PMID: 32649021 PMCID: PMC8247335 DOI: 10.1111/ejn.14903] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 07/03/2020] [Accepted: 07/03/2020] [Indexed: 11/29/2022]
Abstract
The basal ganglia play a crucial role in the control of voluntary movements. Neurons in both the external and internal segments of the globus pallidus, the connecting and output nuclei of the basal ganglia, respectively, change their firing rates in relation to movements. Firing rate changes of movement-related neurons seem to convey signals for motor control. On the other hand, coincident spikes among neurons, that is, correlated activity, may also contribute to motor control. To address this issue, we first identified multiple pallidal neurons receiving inputs from the forelimb regions of the primary motor cortex and supplementary motor area, recorded neuronal activity of these neurons simultaneously, and analyzed their spike correlations while monkeys performed a hand-reaching task. Most (79%) pallidal neurons exhibited task-related firing rate changes, whereas only a small fraction (20%) showed significant but small and short correlated activity during the task performance. These results suggest that motor control signals are conveyed primarily by firing rate changes in the external and internal segments of the globus pallidus and that the contribution of correlated activity may play only a minor role in the healthy state.
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Affiliation(s)
- Woranan Wongmassang
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Physiological Sciences, SOKENDAI (Graduate University for Advanced Studies), Okazaki, Japan
| | - Taku Hasegawa
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Japan
| | - Satomi Chiken
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Physiological Sciences, SOKENDAI (Graduate University for Advanced Studies), Okazaki, Japan
| | - Atsushi Nambu
- Division of System Neurophysiology, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Physiological Sciences, SOKENDAI (Graduate University for Advanced Studies), Okazaki, Japan
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Maizey L, Evans CJ, Muhlert N, Verbruggen F, Chambers CD, Allen CPG. Cortical and subcortical functional specificity associated with response inhibition. Neuroimage 2020; 220:117110. [PMID: 32619711 PMCID: PMC7573537 DOI: 10.1016/j.neuroimage.2020.117110] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 05/18/2020] [Accepted: 06/26/2020] [Indexed: 01/23/2023] Open
Abstract
Is motor response inhibition supported by a specialised neuronal inhibitory control mechanism, or by a more general system of action updating? This pre-registered study employed a context-cueing paradigm requiring both inhibitory and non-inhibitory action updating in combination with functional magnetic resonance imaging to test the specificity of responses under different updating conditions, including the cancellation of actions. Cortical regions of activity were found to be common to multiple forms of action updating. However, functional specificity during response inhibition was observed in the anterior right inferior frontal gyrus. In addition, fronto-subcortical activity was explored using a novel contrast method. These exploratory results indicate that the specificity for response inhibition observed in right prefrontal cortex continued downstream and was observed in right hemisphere subcortical activity, while left hemisphere activity was associated with right-hand response execution. Overall, our findings reveal both common and distinct correlates of response inhibition in prefrontal cortex, with exploratory analyses supporting putative models of subcortical pathways and extending them through the demonstration of lateralisation.
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Affiliation(s)
- Leah Maizey
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, United Kingdom.
| | - C John Evans
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, United Kingdom
| | - Nils Muhlert
- Division of Neuroscience and Experimental Psychology, University of Manchester, United Kingdom
| | | | - Christopher D Chambers
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, United Kingdom
| | - Christopher P G Allen
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, United Kingdom.
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53
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Deffains M, Nguyen TH, Orignac H, Biendon N, Dovero S, Bezard E, Boraud T. In vivo electrophysiological validation of DREADD‐based modulation of pallidal neurons in the non‐human primate. Eur J Neurosci 2020; 53:2192-2204. [DOI: 10.1111/ejn.14746] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 11/30/2022]
Affiliation(s)
- Marc Deffains
- Institut des Maladies Neurodégénératives (IMN) UMR 5293Université de Bordeaux Bordeaux France
- Centre National de la Recherche Scientifique IMNUMR 5293 Bordeaux France
| | - Tho Haï Nguyen
- Institut des Maladies Neurodégénératives (IMN) UMR 5293Université de Bordeaux Bordeaux France
- Centre National de la Recherche Scientifique IMNUMR 5293 Bordeaux France
| | - Hugues Orignac
- Institut des Maladies Neurodégénératives (IMN) UMR 5293Université de Bordeaux Bordeaux France
- Centre National de la Recherche Scientifique IMNUMR 5293 Bordeaux France
| | - Nathalie Biendon
- Institut des Maladies Neurodégénératives (IMN) UMR 5293Université de Bordeaux Bordeaux France
- Centre National de la Recherche Scientifique IMNUMR 5293 Bordeaux France
| | - Sandra Dovero
- Institut des Maladies Neurodégénératives (IMN) UMR 5293Université de Bordeaux Bordeaux France
- Centre National de la Recherche Scientifique IMNUMR 5293 Bordeaux France
| | - Erwan Bezard
- Institut des Maladies Neurodégénératives (IMN) UMR 5293Université de Bordeaux Bordeaux France
- Centre National de la Recherche Scientifique IMNUMR 5293 Bordeaux France
| | - Thomas Boraud
- Institut des Maladies Neurodégénératives (IMN) UMR 5293Université de Bordeaux Bordeaux France
- Centre National de la Recherche Scientifique IMNUMR 5293 Bordeaux France
- IMN Clinique Hôpital Pellegrin Centre hospitalier Universitaire de Bordeaux Place Amélie Raba Léon Bordeaux France
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54
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Pisanò CA, Brugnoli A, Novello S, Caccia C, Keywood C, Melloni E, Vailati S, Padoani G, Morari M. Safinamide inhibits in vivo glutamate release in a rat model of Parkinson's disease. Neuropharmacology 2020; 167:108006. [DOI: 10.1016/j.neuropharm.2020.108006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 01/14/2020] [Accepted: 02/10/2020] [Indexed: 10/25/2022]
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Amita H, Kim HF, Inoue KI, Takada M, Hikosaka O. Optogenetic manipulation of a value-coding pathway from the primate caudate tail facilitates saccadic gaze shift. Nat Commun 2020; 11:1876. [PMID: 32312986 PMCID: PMC7171130 DOI: 10.1038/s41467-020-15802-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 03/10/2020] [Indexed: 12/20/2022] Open
Abstract
In the primate basal ganglia, the caudate tail (CDt) encodes the historical values (good or bad) of visual objects (i.e., stable values), and electrical stimulation of CDt evokes saccadic eye movements. However, it is still unknown how output from CDt conveys stable value signals to govern behavior. Here, we apply a pathway-selective optogenetic manipulation to elucidate how such value information modulates saccades. We express channelrhodopsin-2 in CDt delivered by viral vector injections. Selective optical activation of CDt-derived terminals in the substantia nigra pars reticulata (SNr) inhibits SNr neurons. Notably, these SNr neurons show inhibitory responses to good objects. Furthermore, the optical stimulation causes prolonged excitation of visual-saccadic neurons in the superior colliculus (SC), and induces contralateral saccades. These SC neurons respond more strongly to good than to bad objects in the contralateral hemifield. The present results demonstrate that CDt facilitates saccades toward good objects by serial inhibitory pathways through SNr.
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Affiliation(s)
- Hidetoshi Amita
- Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA.
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi, 484-8506, Japan.
| | - Hyoung F Kim
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Ken-Ichi Inoue
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi, 484-8506, Japan
- PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
| | - Masahiko Takada
- Systems Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi, 484-8506, Japan
| | - Okihide Hikosaka
- Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Orexins role in neurodegenerative diseases: From pathogenesis to treatment. Pharmacol Biochem Behav 2020; 194:172929. [PMID: 32315694 DOI: 10.1016/j.pbb.2020.172929] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 04/07/2020] [Accepted: 04/08/2020] [Indexed: 12/12/2022]
Abstract
Orexin is a neurotransmitter that mainly regulates sleep/wake cycle. In addition to its sleep cycle regulatory role, it is involved in regulation of attention, energy homeostasis, neurogenesis and cognition. Several evidences has shown the involvement of orexin in narcolepsy, but there are also growing evidences that shows the disturbance in orexin system in neurodegenerative diseases including Alzheimer's, Parkinson's, Epilepsy, Huntington's diseases and Amyotrophic lateral sclerosis. Pathogenesis and clinical symptoms of these disorders can be partly attributed from orexin system imbalance. However, there are controversial reports on the exact relationship between orexin and these neurodegenerative diseases. Therefore, the aim of this review is to summarize the current evidences regarding the role of orexin in these neurodegenerative diseases.
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Synaptic and cellular plasticity in Parkinson's disease. Acta Pharmacol Sin 2020; 41:447-452. [PMID: 32112041 PMCID: PMC7470833 DOI: 10.1038/s41401-020-0371-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 01/27/2020] [Indexed: 12/15/2022] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disease, which causes a tremendous socioeconomic burden. PD patients are suffering from debilitating motor and nonmotor symptoms. Cardinal motor symptoms of PD, including akinesia, bradykinesia, resting tremor, and rigidity, are caused by the degeneration of dopaminergic neurons in the substantia nigra pars compacta. In addition, decreased amounts of dopamine (DA) level in the basal ganglia induces numerous adaptive changes at the cellular and synaptic levels in the basal ganglia circuits. These cellular and synaptic adaptations are believed to underlie the emergence and propagation of correlated, rhythmic pattern of activity throughout the interconnected cortico-basal ganglia-thalamocortical network. The widespread pathological pattern of brain activity is closely linked to the devastating motor symptoms of PD. Accumulating evidence suggests that both dopaminergic degeneration and the associated abnormal cellular and circuit activity in the basal ganglia drive the motor symptoms of PD. In this short review I summarize the recent advances in our understanding of synaptic and cellular alterations in two basal ganglia nuclei (i.e. the striatum and the subthalamic nucleus) following a complete loss of DA, and in our conceptual understanding of the cellular and circuit bases for the pathological pattern of brain activity in parkinsonian state.
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Abstract
Background:Tics, defined as quick, rapid, sudden, recurrent, non-rhythmic motor movements or vocalizations are required components of Tourette Syndrome (TS) - a complex disorder characterized by the presence of fluctuating, chronic motor and vocal tics, and the presence of co-existing neuropsychological problems. Despite many advances, the underlying pathophysiology of tics/TS remains unknown.Objective:To address a variety of controversies surrounding the pathophysiology of TS. More specifically: 1) the configuration of circuits likely involved; 2) the role of inhibitory influences on motor control; 3) the classification of tics as either goal-directed or habitual behaviors; 4) the potential anatomical site of origin, e.g. cortex, striatum, thalamus, cerebellum, or other(s); and 5) the role of specific neurotransmitters (dopamine, glutamate, GABA, and others) as possible mechanisms (Abstract figure).Methods:Existing evidence from current clinical, basic science, and animal model studies are reviewed to provide: 1) an expanded understanding of individual components and the complex integration of the Cortico-Basal Ganglia-Thalamo-Cortical (CBGTC) circuit - the pathway involved with motor control; and 2) scientific data directly addressing each of the aforementioned controversies regarding pathways, inhibition, classification, anatomy, and neurotransmitters.Conclusion:Until a definitive pathophysiological mechanism is identified, one functional approach is to consider that a disruption anywhere within CBGTC circuitry, or a brain region inputting to the motor circuit, can lead to an aberrant message arriving at the primary motor cortex and enabling a tic. Pharmacologic modulation may be therapeutically beneficial, even though it might not be directed toward the primary abnormality.
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Affiliation(s)
- Harvey S. Singer
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, United States
| | - Farhan Augustine
- Department of Neurology, Johns Hopkins Hospital, Baltimore, MD, United States
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G A, O P, E CM, M GR. Reduction of dopaminergic transmission in the globus pallidus increases anxiety-like behavior without altering motor activity. Behav Brain Res 2020; 386:112589. [PMID: 32194191 DOI: 10.1016/j.bbr.2020.112589] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 02/26/2020] [Accepted: 02/27/2020] [Indexed: 12/29/2022]
Abstract
The globus pallidus (GP) plays an important role in the flow of information between input and output structures of the basal ganglia (BG) circuit. In addition to participating in motor control, the GP may also be involved in cognitive and emotional functions related to the symptoms of patients with Parkinson's disease (PD). Since the GP receives dopaminergic innervation from the substantia nigra pars compacta (SNc), it is important to determine whether a local dopamine (DA) deficit in the GP is related not only to motor but also to the cognitive and emotional alterations of PD. The aim of this study was to examine the effects of lesions in the GP (induced by 6-OHDA) on anxiety, depression and ambulation in rats. Such lesions are known to reduce dopaminergic innervation in this brain structure. Additionally, the effect on DA receptors in the GP was tested by local administration of the dopamine agonist PD168,077, antagonist haloperidol and psychostimulant amphetamine. Experimental anxiety was evaluated with the elevated plus maze (EPM), burying behavior test (BBT) and social interaction test, while depressive-like behavior was assessed with the sucrose preference test. Rats with unilateral and bilateral lesions showed a higher level of anxiety than intact animals in both the EPM and BBT, an effect also obtained after intrapallidal injection of haloperidol. The administration of methamphetamine or PD-168.077 caused the opposite effect. The dopaminergic lesions in the GP did not affect sucrose preference, social interaction or ambulation. These results show that dopamine in the GP, acting through D2 or D4 receptors, may be involved in the manifestation of anxiety, a non-motor symptom of PD that often appears before motor symptoms.
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Affiliation(s)
- Avila G
- Escuela Nacional de Ciencias Biológicas, Instituto Politecnico Nacional, Wilfrido Massieu sn, San Pedro Zacatenco, CP 07738, Ciudad de México, Mexico
| | - Picazo O
- Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Diaz Mirón, Col. Santo Tomás CP.11340, Ciudad de México, Mexico
| | - Chuc-Meza E
- Escuela Nacional de Ciencias Biológicas, Instituto Politecnico Nacional, Wilfrido Massieu sn, San Pedro Zacatenco, CP 07738, Ciudad de México, Mexico
| | - García-Ramirez M
- Escuela Nacional de Ciencias Biológicas, Instituto Politecnico Nacional, Wilfrido Massieu sn, San Pedro Zacatenco, CP 07738, Ciudad de México, Mexico.
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60
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Chen XY, Xue Y, Chen H, Chen L. The globus pallidus as a target for neuropeptides and endocannabinoids participating in central activities. Peptides 2020; 124:170210. [PMID: 31778724 DOI: 10.1016/j.peptides.2019.170210] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 11/14/2019] [Accepted: 11/21/2019] [Indexed: 12/12/2022]
Abstract
The globus pallidus in the basal ganglia plays an important role in movement regulation. Neuropeptides and endocannabinoids are neuronal signalling molecules that influence the functions of the whole brain. Endocannabinoids, enkephalin, substance P, neurotensin, orexin, somatostatin and pituitary adenylate cyclase-activating polypeptides are richly concentrated in the globus pallidus. Neuropeptides and endocannabinoids exert excitatory or inhibitory effects in the globus pallidus mainly by modulating GABAergic, glutamatergic and dopaminergic neurotransmission, as well as many ionic mechanisms. Pallidal neuropeptides and endocannabinoids are associated with the pathophysiology of a number of neurological disorders, such as Parkinson's disease, Huntington's disease, schizophrenia, and depression. The levels of neuropeptides and endocannabinoids and their receptors in the globus pallidus change in neurological diseases. It has been demonstrated that spontaneous firing activity of globus pallidus neurons is closely related to the manifestations of Parkinson's disease. Therefore, the neuropeptides and endocannabinoids in the globus pallidus may function as potential targets for treatment in some neurological diseases. In this review, we highlight the morphology and function of neuropeptides and endocannabinoids in the globus pallidus and their involvement in neurological diseases.
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Affiliation(s)
- Xin-Yi Chen
- Department of Pathology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China; Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Yan Xue
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Hua Chen
- Department of Pathology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China.
| | - Lei Chen
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, China.
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61
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Li R, Wang X, Lin F, Song T, Zhu X, Lei H. Mapping accumulative whole-brain activities during environmental enrichment with manganese-enhanced magnetic resonance imaging. Neuroimage 2020; 210:116588. [PMID: 32004718 DOI: 10.1016/j.neuroimage.2020.116588] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 01/10/2020] [Accepted: 01/24/2020] [Indexed: 11/17/2022] Open
Abstract
An enriched environment (EE) provides multi-dimensional stimuli to the brain. EE exposure for days to months induces functional and structural neuroplasticity. In this study, manganese-enhanced magnetic resonance imaging (MEMRI) was used to map the accumulative whole-brain activities associated with a 7-day EE exposure in freely-moving adult male mice, followed by c-Fos immunochemical assessments. Relative to the mice residing in a standard environment (SE), the mice subjected to EE treatment had significantly enhanced regional MEMRI signal intensities in the prefrontal cortex, somatosensory cortices, basal ganglia, amygdala, motor thalamus, lateral hypothalamus, ventral hippocampus and midbrain dopaminergic areas at the end of the 7-day exposure, likely attributing to enhanced Mn2+ uptake/transport associated with brain activities at both the regional and macroscale network levels. Some of, but not all, the brain regions in the EE-treated mice showing enhanced MEMRI signal intensity had accompanying increases in c-Fos expression. The EE-treated mice were also found to have significantly increased overall amount of food consumption, decreased body weight gain and upregulated tyrosine hydroxylase (TH) expression in the midbrain dopaminergic areas. Taken together, these results demonstrated that the 7-day EE exposure was associated with elevated cumulative activities in the nigrostriatal, mesolimbic and corticostriatal circuits underpinning reward, motivation, cognition, motor control and appetite regulation. Such accumulative activities might have served as the substrate of EE-related neuroplasticity and the beneficial effects of EE treatment on neurological/psychiatric conditions including drug addiction, Parkinson's disease and eating disorder.
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Affiliation(s)
- Ronghui Li
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, PR China; National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, PR China
| | - Xuxia Wang
- National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, PR China
| | - Fuchun Lin
- National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, PR China
| | - Tao Song
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, PR China; National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, PR China
| | - Xutao Zhu
- Shenzhen Key Lab of Neuropsychiatric Modulation and Collaborative Innovation Center for Brain Science, CAS Center for Excellence in Brain Science and Intelligence Technology, Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Hao Lei
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, PR China; National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, PR China.
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62
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Abecassis ZA, Berceau BL, Win PH, García D, Xenias HS, Cui Q, Pamukcu A, Cherian S, Hernández VM, Chon U, Lim BK, Kim Y, Justice NJ, Awatramani R, Hooks BM, Gerfen CR, Boca SM, Chan CS. Npas1 +-Nkx2.1 + Neurons Are an Integral Part of the Cortico-pallido-cortical Loop. J Neurosci 2020; 40:743-768. [PMID: 31811030 PMCID: PMC6975296 DOI: 10.1523/jneurosci.1199-19.2019] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 11/21/2019] [Accepted: 11/26/2019] [Indexed: 11/21/2022] Open
Abstract
Within the basal ganglia circuit, the external globus pallidus (GPe) is critically involved in motor control. Aside from Foxp2+ neurons and ChAT+ neurons that have been established as unique neuron types, there is little consensus on the classification of GPe neurons. Properties of the remaining neuron types are poorly defined. In this study, we leverage new mouse lines, viral tools, and molecular markers to better define GPe neuron subtypes. We found that Sox6 represents a novel, defining marker for GPe neuron subtypes. Lhx6+ neurons that lack the expression of Sox6 were devoid of both parvalbumin and Npas1. This result confirms previous assertions of the existence of a unique Lhx6+ population. Neurons that arise from the Dbx1+ lineage were similarly abundant in the GPe and displayed a heterogeneous makeup. Importantly, tracing experiments revealed that Npas1+-Nkx2.1+ neurons represent the principal noncholinergic, cortically-projecting neurons. In other words, they form the pallido-cortical arm of the cortico-pallido-cortical loop. Our data further show that pyramidal-tract neurons in the cortex collateralized within the GPe, forming a closed-loop system between the two brain structures. Overall, our findings reconcile some of the discrepancies that arose from differences in techniques or the reliance on preexisting tools. Although spatial distribution and electrophysiological properties of GPe neurons reaffirm the diversification of GPe subtypes, statistical analyses strongly support the notion that these neuron subtypes can be categorized under the two principal neuron classes: PV+ neurons and Npas1+ neurons.SIGNIFICANCE STATEMENT The poor understanding of the neuronal composition in the external globus pallidus (GPe) undermines our ability to interrogate its precise behavioral and disease involvements. In this study, 12 different genetic crosses were used, hundreds of neurons were electrophysiologically characterized, and >100,000 neurons were histologically- and/or anatomically-profiled. Our current study further establishes the segregation of GPe neuron classes and illustrates the complexity of GPe neurons in adult mice. Our results support the idea that Npas1+-Nkx2.1+ neurons are a distinct GPe neuron subclass. By providing a detailed analysis of the organization of the cortico-pallidal-cortical projection, our findings establish the cellular and circuit substrates that can be important for motor function and dysfunction.
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Affiliation(s)
- Zachary A Abecassis
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Brianna L Berceau
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Phyo H Win
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Daniela García
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Harry S Xenias
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Qiaoling Cui
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Arin Pamukcu
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Suraj Cherian
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Vivian M Hernández
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Uree Chon
- Department of Neural and Behavioral Sciences, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania
| | - Byung Kook Lim
- Neurobiology Section, Biological Sciences Division, University of California San Diego, La Jolla, California
| | - Yongsoo Kim
- Department of Neural and Behavioral Sciences, College of Medicine, Pennsylvania State University, Hershey, Pennsylvania
| | - Nicholas J Justice
- Center for Metabolic and degenerative disease, Institute of Molecular Medicine, University of Texas, Houston, Texas
- Department of Integrative Pharmacology, University of Texas, Houston, Texas
| | - Raj Awatramani
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Bryan M Hooks
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Charles R Gerfen
- Laboratory of Systems Neuroscience, National Institute of Mental Health, Bethesda, Maryland, and
| | - Simina M Boca
- Innovation Center for Biomedical Informatics, Georgetown University Medical Center, Washington, District of Columbia
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois,
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63
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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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Review of bilirubin neurotoxicity I: molecular biology and neuropathology of disease. Pediatr Res 2020; 87:327-331. [PMID: 31600770 DOI: 10.1038/s41390-019-0608-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/26/2019] [Accepted: 09/27/2019] [Indexed: 12/11/2022]
Abstract
Despite the availability of successful prevention strategies to prevent excessive hyperbilirubinemia, the neurological sequelae of bilirubin neurotoxicity (BNTx) still occur throughout the world. Kernicterus, encephalopathy due to BNTx, is now understood to be a spectrum of severity and phenotypes known as kernicterus spectrum disorder (KSD). A better understanding of the selective neuropathology and molecular biology of BNTx and using consistent clinical definitions of KSDs as outcome measure can lead to more accurately predicting the risk and causes of BNTx and KSDs. In Part I of our two-part review, we will summarize current and recent advances in the understanding of the selective neuropathology and molecular biology of the disease. Herein we emphasize the role of unbound, free unconjugated bilirubin as well as genetic contributions to the susceptibility BNTx and the development of KSDs. In Part II, we focus on current and possible novel methods to prevent BNTx and ABE and treat ABE and KSDs.
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Chazalon M, Paredes-Rodriguez E, Morin S, Martinez A, Cristóvão-Ferreira S, Vaz S, Sebastiao A, Panatier A, Boué-Grabot E, Miguelez C, Baufreton J. GAT-3 Dysfunction Generates Tonic Inhibition in External Globus Pallidus Neurons in Parkinsonian Rodents. Cell Rep 2019; 23:1678-1690. [PMID: 29742425 DOI: 10.1016/j.celrep.2018.04.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 03/08/2018] [Accepted: 04/02/2018] [Indexed: 12/26/2022] Open
Abstract
The external globus pallidus (GP) is a key GABAergic hub in the basal ganglia (BG) circuitry, a neuronal network involved in motor control. In Parkinson's disease (PD), the rate and pattern of activity of GP neurons are profoundly altered and contribute to the motor symptoms of the disease. In rodent models of PD, the striato-pallidal pathway is hyperactive, and extracellular GABA concentrations are abnormally elevated in the GP, supporting the hypothesis of an alteration of neuronal and/or glial clearance of GABA. Here, we discovered the existence of persistent GABAergic tonic inhibition in GP neurons of dopamine-depleted (DD) rodent models. We showed that glial GAT-3 transporters are downregulated while neuronal GAT-1 function remains normal in DD rodents. Finally, we showed that blocking GAT-3 activity in vivo alters the motor coordination of control rodents, suggesting that GABAergic tonic inhibition in the GP contributes to the pathophysiology of PD.
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Affiliation(s)
- Marine Chazalon
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France
| | | | - Stéphanie Morin
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France
| | - Audrey Martinez
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France
| | - Sofia Cristóvão-Ferreira
- Institute of Pharmacology and Neurosciences, Faculty of Medicine, and Unit of Neuroscience, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal
| | - Sandra Vaz
- Institute of Pharmacology and Neurosciences, Faculty of Medicine, and Unit of Neuroscience, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal
| | - Ana Sebastiao
- Institute of Pharmacology and Neurosciences, Faculty of Medicine, and Unit of Neuroscience, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal
| | - Aude Panatier
- INSERM U1215, Neurocentre Magendie, 33000 Bordeaux, France; Université de Bordeaux, 33000 Bordeaux, France
| | - Eric Boué-Grabot
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France
| | - Cristina Miguelez
- Department of Pharmacology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain
| | - Jérôme Baufreton
- Université de Bordeaux, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France; CNRS UMR 5293, Institut des Maladies Neurodégénératives, 33000 Bordeaux, France.
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66
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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; 8:49511. [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] [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 Science, Doshisha University, Kyotanabe, Japan
| | - Susumu Takahashi
- Laboratory of Neural Circuitry, Graduate School of Brain Science, Doshisha University, Kyotanabe, Japan.,Laboratory of Cognitive and Behavioral Neuroscience, Graduate School of Brain Science, Doshisha University, Kyotanabe, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Japan
| | - Fumino Fujiyama
- Laboratory of Neural Circuitry, Graduate School of Brain Science, Doshisha University, Kyotanabe, Japan
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67
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Schmalz J, Kumar G. Controlling Synchronization of Spiking Neuronal Networks by Harnessing Synaptic Plasticity. Front Comput Neurosci 2019; 13:61. [PMID: 31551743 PMCID: PMC6737503 DOI: 10.3389/fncom.2019.00061] [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: 03/21/2019] [Accepted: 08/21/2019] [Indexed: 12/19/2022] Open
Abstract
Disrupting the pathological synchronous firing patterns of neurons with high frequency stimulation is a common treatment for Parkinsonian symptoms and epileptic seizures when pharmaceutical drugs fail. In this paper, our goal is to design a desynchronization strategy for large networks of spiking neurons such that the neuronal activity of the network remains in the desynchronized regime for a long period of time after the removal of the stimulation. We develop a novel "Forced Temporal-Spike Time Stimulation (FTSTS)" strategy that harnesses the spike-timing dependent plasticity to control the synchronization of neural activity in the network by forcing the neurons in the network to artificially fire in a specific temporal pattern. Our strategy modulates the synaptic strengths of selective synapses to achieve a desired synchrony of neural activity in the network. Our simulation results show that the FTSTS strategy can effectively synchronize or desynchronize neural activity in large spiking neuron networks and keep them in the desired state for a long period of time after the removal of the external stimulation. Using simulations, we demonstrate the robustness of our strategy in desynchronizing neural activity of networks against uncertainties in the designed stimulation pulses and network parameters. Additionally, we show in simulation, how our strategy could be incorporated within the existing desynchronization strategies to improve their overall efficacy in desynchronizing large networks. Our proposed strategy provides complete control over the synchronization of neurons in large networks and can be used to either synchronize or desynchronize neural activity based on specific applications. Moreover, it can be incorporated within other desynchronization strategies to improve the efficacy of existing therapies for numerous neurological and psychiatric disorders associated with pathological synchronization.
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Affiliation(s)
| | - Gautam Kumar
- Department of Chemical and Materials Engineering, University of Idaho, Moscow, ID, United States
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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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69
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Wang Y, Chen AQ, Xue Y, Liu MF, Liu C, Liu YH, Pan YP, Diao HL, Chen L. Orexins alleviate motor deficits via increasing firing activity of pallidal neurons in a mouse model of Parkinson's disease. Am J Physiol Cell Physiol 2019; 317:C800-C812. [PMID: 31365289 DOI: 10.1152/ajpcell.00125.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Orexin is a peptide neurotransmitter released in the globus pallidus. Morphological evidence reveals that both orexin 1 receptor (OX1R) and orexin 2 receptor (OX2R) exist in the globus pallidus. Here we showed that bilateral microinjection of both orexin-A and orexin-B into the globus pallidus alleviated motor deficits in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonian mice. Further in vivo extracellular single-unit recording revealed that the basal spontaneous firing rate of the globus pallidus neurons in MPTP parkinsonian mice was slower than that of normal mice. Application of orexin-A or orexin-B significantly increased the spontaneous firing rate of pallidal neurons. The influx of Ca2+ through the L-type Ca2+ channel is the major mechanism involved in orexin-induced excitation in the globus pallidus. Orexin-A-induced increase in firing rate of pallidal neurons in MPTP parkinsonian mice was stronger than that of normal mice. Orexin-A exerted both electrophysiological and behavioral effects mainly via OX1R, and orexin-B exerted the effects via OX2R. Endogenous orexins modulated the excitability of globus pallidus neurons mainly through OX1R. The present behavioral and electrophysiological results suggest that orexins ameliorate parkinsonian motor deficits through increasing the spontaneous firing of globus pallidus neurons.
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Affiliation(s)
- Ying Wang
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - An-Qi Chen
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Yan Xue
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Mei-Fang Liu
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Cui Liu
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Yun-Hai Liu
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Yi-Peng Pan
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Hui-Ling Diao
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
| | - Lei Chen
- Department of Physiology, School of Basic Medicine, Qingdao University, Qingdao, China
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70
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Adaptive delivery of continuous and delayed feedback deep brain stimulation - a computational study. Sci Rep 2019; 9:10585. [PMID: 31332226 PMCID: PMC6646395 DOI: 10.1038/s41598-019-47036-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 07/09/2019] [Indexed: 12/15/2022] Open
Abstract
Adaptive deep brain stimulation (aDBS) is a closed-loop method, where high-frequency DBS is turned on and off according to a feedback signal, whereas conventional high-frequency DBS (cDBS) is delivered permanently. Using a computational model of subthalamic nucleus and external globus pallidus, we extend the concept of adaptive stimulation by adaptively controlling not only continuous, but also demand-controlled stimulation. Apart from aDBS and cDBS, we consider continuous pulsatile linear delayed feedback stimulation (cpLDF), specifically designed to induce desynchronization. Additionally, we combine adaptive on-off delivery with continuous delayed feedback modulation by introducing adaptive pulsatile linear delayed feedback stimulation (apLDF), where cpLDF is turned on and off using pre-defined amplitude thresholds. By varying the stimulation parameters of cDBS, aDBS, cpLDF, and apLDF we obtain optimal parameter ranges. We reveal a simple relation between the thresholds of the local field potential (LFP) for aDBS and apLDF, the extent of the stimulation-induced desynchronization, and the integral stimulation time required. We find that aDBS and apLDF can be more efficient in suppressing abnormal synchronization than continuous simulation. However, apLDF still remains more efficient and also causes a stronger reduction of the LFP beta burst length. Hence, adaptive on-off delivery may further improve the intrinsically demand-controlled pLDF.
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Jellinger KA. Neuropathology and pathogenesis of extrapyramidal movement disorders: a critical update-I. Hypokinetic-rigid movement disorders. J Neural Transm (Vienna) 2019; 126:933-995. [PMID: 31214855 DOI: 10.1007/s00702-019-02028-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 06/05/2019] [Indexed: 02/06/2023]
Abstract
Extrapyramidal movement disorders include hypokinetic rigid and hyperkinetic or mixed forms, most of them originating from dysfunction of the basal ganglia (BG) and their information circuits. The functional anatomy of the BG, the cortico-BG-thalamocortical, and BG-cerebellar circuit connections are briefly reviewed. Pathophysiologic classification of extrapyramidal movement disorder mechanisms distinguish (1) parkinsonian syndromes, (2) chorea and related syndromes, (3) dystonias, (4) myoclonic syndromes, (5) ballism, (6) tics, and (7) tremor syndromes. Recent genetic and molecular-biologic classifications distinguish (1) synucleinopathies (Parkinson's disease, dementia with Lewy bodies, Parkinson's disease-dementia, and multiple system atrophy); (2) tauopathies (progressive supranuclear palsy, corticobasal degeneration, FTLD-17; Guamian Parkinson-dementia; Pick's disease, and others); (3) polyglutamine disorders (Huntington's disease and related disorders); (4) pantothenate kinase-associated neurodegeneration; (5) Wilson's disease; and (6) other hereditary neurodegenerations without hitherto detected genetic or specific markers. The diversity of phenotypes is related to the deposition of pathologic proteins in distinct cell populations, causing neurodegeneration due to genetic and environmental factors, but there is frequent overlap between various disorders. Their etiopathogenesis is still poorly understood, but is suggested to result from an interaction between genetic and environmental factors. Multiple etiologies and noxious factors (protein mishandling, mitochondrial dysfunction, oxidative stress, excitotoxicity, energy failure, and chronic neuroinflammation) are more likely than a single factor. Current clinical consensus criteria have increased the diagnostic accuracy of most neurodegenerative movement disorders, but for their definite diagnosis, histopathological confirmation is required. We present a timely overview of the neuropathology and pathogenesis of the major extrapyramidal movement disorders in two parts, the first one dedicated to hypokinetic-rigid forms and the second to hyperkinetic disorders.
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Affiliation(s)
- Kurt A Jellinger
- Institute of Clinical Neurobiology, Alberichgasse 5/13, 1150, Vienna, Austria.
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72
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Cacciola A, Milardi D, Bertino S, Basile GA, Calamuneri A, Chillemi G, Rizzo G, Anastasi G, Quartarone A. Structural connectivity-based topography of the human globus pallidus: Implications for therapeutic targeting in movement disorders. Mov Disord 2019; 34:987-996. [PMID: 31077436 DOI: 10.1002/mds.27712] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 03/31/2019] [Accepted: 04/04/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Understanding the topographical organization of the cortico-basal ganglia circuitry is of pivotal importance because of the spreading of techniques such as DBS and, more recently, MR-guided focused ultrasound for the treatment of movement disorders. A growing body of evidence has described both direct cortico- and dento-pallidal connections, although the topographical organization in vivo of these pathways in the human brain has never been reported. OBJECTIVE To investigate the topographical organization of cortico- and dento-pallidal pathways by means of diffusion MRI tractography and connectivity based parcellation. METHODS High-quality data from 100 healthy subjects from the Human Connectome Project repository were utilized. Constrained spherical deconvolution-based tractography was used to reconstruct structural cortico- and dento-pallidal connectivity. Connectivity-based parcellation was performed with a hypothesis-driven approach at three different levels: functional regions (limbic, associative, sensorimotor, and other), lobes, and gyral subareas. RESULTS External globus pallidus segregated into a ventral associative cluster, a dorsal sensorimotor cluster, and a caudal "other" cluster on the base of its cortical connectivity. Dento-pallidal connections clustered only in the internal globus pallidus, where also associative and sensorimotor clusters were identified. Lobar parcellation revealed the presence in the external globus pallidus of dissociable clusters for each cortical lobe (frontal, parietal, temporal, and occipital), whereas in internal globus pallidus only frontal and parietal clusters were found out. CONCLUSION We mapped the topographical organization of both internal and external globus pallidus according to cortical and cerebellar connections. These anatomical data could be useful in DBS, radiosurgery and MR-guided focused ultrasound targeting for treating motor and nonmotor symptoms in movement disorders. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Alberto Cacciola
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Demetrio Milardi
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy.,IRCCS Centro Neurolesi "Bonino Pulejo", Messina, Italy
| | - Salvatore Bertino
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Gianpaolo Antonio Basile
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | | | | | - Giuseppina Rizzo
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Giuseppe Anastasi
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Angelo Quartarone
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
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73
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Wu YW, Ding JB. A cell-type-specific jolt for motor disorders. Nat Neurosci 2019; 20:763-765. [PMID: 28542150 DOI: 10.1038/nn.4565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yu-Wei Wu
- Department of Neurosurgery and the Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, California, USA
| | - Jun B Ding
- Department of Neurosurgery and the Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Palo Alto, California, USA
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Muddapu VR, Mandali A, Chakravarthy VS, Ramaswamy S. A Computational Model of Loss of Dopaminergic Cells in Parkinson's Disease Due to Glutamate-Induced Excitotoxicity. Front Neural Circuits 2019; 13:11. [PMID: 30858799 PMCID: PMC6397878 DOI: 10.3389/fncir.2019.00011] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 02/05/2019] [Indexed: 01/04/2023] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disease associated with progressive and inexorable loss of dopaminergic cells in Substantia Nigra pars compacta (SNc). Although many mechanisms have been suggested, a decisive root cause of this cell loss is unknown. A couple of the proposed mechanisms, however, show potential for the development of a novel line of PD therapeutics. One of these mechanisms is the peculiar metabolic vulnerability of SNc cells compared to other dopaminergic clusters; the other is the SubThalamic Nucleus (STN)-induced excitotoxicity in SNc. To investigate the latter hypothesis computationally, we developed a spiking neuron network-model of SNc-STN-GPe system. In the model, prolonged stimulation of SNc cells by an overactive STN leads to an increase in ‘stress' variable; when the stress in a SNc neuron exceeds a stress threshold, the neuron dies. The model shows that the interaction between SNc and STN involves a positive-feedback due to which, an initial loss of SNc cells that crosses a threshold causes a runaway-effect, leading to an inexorable loss of SNc cells, strongly resembling the process of neurodegeneration. The model further suggests a link between the two aforementioned mechanisms of SNc cell loss. Our simulation results show that the excitotoxic cause of SNc cell loss might initiate by weak-excitotoxicity mediated by energy deficit, followed by strong-excitotoxicity, mediated by a disinhibited STN. A variety of conventional therapies were simulated to test their efficacy in slowing down SNc cell loss. Among them, glutamate inhibition, dopamine restoration, subthalamotomy and deep brain stimulation showed superior neuroprotective-effects in the proposed model.
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Affiliation(s)
| | - Alekhya Mandali
- Department of Psychiatry, Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom
| | - V Srinivasa Chakravarthy
- Computational Neuroscience Lab, Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, IIT-Madras, Chennai, India
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Deffains M, Bergman H. Parkinsonism-related β oscillations in the primate basal ganglia networks – Recent advances and clinical implications. Parkinsonism Relat Disord 2019; 59:2-8. [DOI: 10.1016/j.parkreldis.2018.12.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 12/12/2018] [Accepted: 12/13/2018] [Indexed: 10/27/2022]
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Augustine F, Singer HS. Merging the Pathophysiology and Pharmacotherapy of Tics. Tremor Other Hyperkinet Mov (N Y) 2019; 8:595. [PMID: 30643668 PMCID: PMC6329776 DOI: 10.7916/d8h14jtx] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 09/28/2018] [Indexed: 12/14/2022] Open
Abstract
Background Anatomically, cortical-basal ganglia-thalamo-cortical (CBGTC) circuits have an essential role in the expression of tics. At the biochemical level, the proper conveyance of messages through these circuits requires several functionally integrated neurotransmitter systems. In this manuscript, evidence supporting proposed pathophysiological abnormalities, both anatomical and chemical is reviewed. In addition, the results of standard and emerging tic-suppressing therapies affecting nine separate neurotransmitter systems are discussed. The goal of this review is to integrate our current understanding of the pathophysiology of Tourette syndrome (TS) with present and proposed pharmacotherapies for tic suppression. Methods For this manuscript, literature searches were conducted for both current basic science and clinical information in PubMed, Google-Scholar, and other scholarly journals to September 2018. Results The precise primary site of abnormality for tics remains undetermined. Although many pathophysiologic hypotheses favor a specific abnormality of the cortex, striatum, or globus pallidus, others recognize essential influences from regions such as the thalamus, cerebellum, brainstem, and ventral striatum. Some prefer an alteration within direct and indirect pathways, whereas others believe this fails to recognize the multiple interactions within and between CBGTC circuits. Although research and clinical evidence supports involvement of the dopaminergic system, additional data emphasizes the potential roles for several other neurotransmitter systems. Discussion A greater understanding of the primary neurochemical defect in TS would be extremely valuable for the development of new tic-suppressing therapies. Nevertheless, recognizing the varied and complex interactions that exist in a multi-neurotransmitter system, successful therapy may not require direct targeting of the primary abnormality.
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Affiliation(s)
- Farhan Augustine
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Harvey S. Singer
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Meszaros J, Cheung T, Erler MM, Kang UJ, Sames D, Kellendonk C, Sulzer D. Evoked transients of pH-sensitive fluorescent false neurotransmitter reveal dopamine hot spots in the globus pallidus. eLife 2018; 7:42383. [PMID: 30566076 PMCID: PMC6324876 DOI: 10.7554/elife.42383] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 12/18/2018] [Indexed: 12/30/2022] Open
Abstract
Dopamine neurotransmission is suspected to play important physiological roles in multiple sparsely innervated brain nuclei, but there has not been a means to measure synaptic dopamine release in such regions. The globus pallidus externa (GPe) is a major locus in the basal ganglia that displays a sparse innervation of en passant dopamine axonal fibers. Due to the low levels of innervation that preclude electrochemical analysis, it is unknown if these axons engage in neurotransmission. To address this, we introduce an optical approach using a pH-sensitive fluorescent false neurotransmitter, FFN102, that exhibits increased fluorescence upon exocytosis from the acidic synaptic vesicle to the neutral extracellular milieu. In marked contrast to the striatum, FFN102 transients in the mouse GPe were spatially heterogeneous and smaller than in striatum with the exception of sparse hot spots. GPe transients were also significantly enhanced by high frequency stimulation. Our results support hot spots of dopamine release from substantia nigra axons.
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Affiliation(s)
- Jozsef Meszaros
- Laboratory for Functional Optical Imaging, Department of Biomedical Engineering, Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, United States.,Graduate Program in Neurobiology and Behavior, Columbia University, New York, United States
| | - Timothy Cheung
- Department of Neurology, Columbia University, New York, United States
| | - Maya M Erler
- Graduate Program in Pharmacology, College of Physicians and Surgeons, Columbia University, New York, United States
| | - Un Jung Kang
- Department of Neurology, Columbia University, New York, United States
| | - Dalibor Sames
- Department of Chemistry and NeuroTechnology Center, Columbia University, New York, United States
| | - Christoph Kellendonk
- Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, United States.,Department of Psychiatry, Columbia University, New York, United States.,Department of Pharmacology, Columbia University, New York, United States
| | - David Sulzer
- Department of Neurology, Columbia University, New York, United States.,Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, United States.,Department of Psychiatry, Columbia University, New York, United States.,Department of Pharmacology, Columbia University, New York, United States
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78
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Assaf F, Schiller Y. A chemogenetic approach for treating experimental Parkinson's disease. Mov Disord 2018; 34:469-479. [DOI: 10.1002/mds.27554] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 09/28/2018] [Accepted: 10/10/2018] [Indexed: 12/12/2022] Open
Affiliation(s)
- Fadi Assaf
- The Rappaport Faculty of MedicineTechnion–Israel Institute of Technology Haifa Israel
| | - Yitzhak Schiller
- The Rappaport Faculty of MedicineTechnion–Israel Institute of Technology Haifa Israel
- Department of NeurologyRambam Medical Center Haifa Israel
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79
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Daneshzand M, Faezipour M, Barkana BD. Robust desynchronization of Parkinson's disease pathological oscillations by frequency modulation of delayed feedback deep brain stimulation. PLoS One 2018; 13:e0207761. [PMID: 30458039 PMCID: PMC6245797 DOI: 10.1371/journal.pone.0207761] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 11/06/2018] [Indexed: 11/30/2022] Open
Abstract
The hyperkinetic symptoms of Parkinson's Disease (PD) are associated with the ensembles of interacting oscillators that cause excess or abnormal synchronous behavior within the Basal Ganglia (BG) circuitry. Delayed feedback stimulation is a closed loop technique shown to suppress this synchronous oscillatory activity. Deep Brain Stimulation (DBS) via delayed feedback is known to destabilize the complex intermittent synchronous states. Computational models of the BG network are often introduced to investigate the effect of delayed feedback high frequency stimulation on partially synchronized dynamics. In this study, we develop a reduced order model of four interacting nuclei of the BG as well as considering the Thalamo-Cortical local effects on the oscillatory dynamics. This model is able to capture the emergence of 34 Hz beta band oscillations seen in the Local Field Potential (LFP) recordings of the PD state. Train of high frequency pulses in a delayed feedback stimulation has shown deficiencies such as strengthening the synchronization in case of highly fluctuating neuronal activities, increasing the energy consumed as well as the incapability of activating all neurons in a large-scale network. To overcome these drawbacks, we propose a new feedback control variable based on the filtered and linearly delayed LFP recordings. The proposed control variable is then used to modulate the frequency of the stimulation signal rather than its amplitude. In strongly coupled networks, oscillations reoccur as soon as the amplitude of the stimulus signal declines. Therefore, we show that maintaining a fixed amplitude and modulating the frequency might ameliorate the desynchronization process, increase the battery lifespan and activate substantial regions of the administered DBS electrode. The charge balanced stimulus pulse itself is embedded with a delay period between its charges to grant robust desynchronization with lower amplitudes needed. The efficiency of the proposed Frequency Adjustment Stimulation (FAS) protocol in a delayed feedback method might contribute to further investigation of DBS modulations aspired to address a wide range of abnormal oscillatory behavior observed in neurological disorders.
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Affiliation(s)
- Mohammad Daneshzand
- D-BEST Lab, Departments of Computer Science and Engineering and Biomedical Engineering, University of Bridgeport, Bridgeport, CT, United States of America
| | - Miad Faezipour
- D-BEST Lab, Departments of Computer Science and Engineering and Biomedical Engineering, University of Bridgeport, Bridgeport, CT, United States of America
| | - Buket D. Barkana
- Department of Electrical Engineering, University of Bridgeport, Bridgeport, CT, United States of America
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80
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Plotkin JL, Goldberg JA. Thinking Outside the Box (and Arrow): Current Themes in Striatal Dysfunction in Movement Disorders. Neuroscientist 2018; 25:359-379. [PMID: 30379121 PMCID: PMC6529282 DOI: 10.1177/1073858418807887] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The basal ganglia are an intricately connected assembly of subcortical nuclei, forming the core of an adaptive network connecting cortical and thalamic circuits. For nearly three decades, researchers and medical practitioners have conceptualized how the basal ganglia circuit works, and how its pathology underlies motor disorders such as Parkinson's and Huntington's diseases, using what is often referred to as the "box-and-arrow model": a circuit diagram showing the broad strokes of basal ganglia connectivity and the pathological increases and decreases in the weights of specific connections that occur in disease. While this model still has great utility and has led to groundbreaking strategies to treat motor disorders, our evolving knowledge of basal ganglia function has made it clear that this classic model has several shortcomings that severely limit its predictive and descriptive abilities. In this review, we will focus on the striatum, the main input nucleus of the basal ganglia. We describe recent advances in our understanding of the rich microcircuitry and plastic capabilities of the striatum, factors not captured by the original box-and-arrow model, and provide examples of how such advances inform our current understanding of the circuit pathologies underlying motor disorders.
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Affiliation(s)
- Joshua L Plotkin
- Department of Neurobiology and Behavior, Stony Brook University School of Medicine, Stony Brook, NY, USA
| | - Joshua A Goldberg
- Department of Medical Neurobiology, The Hebrew University of Jerusalem, Jerusalem, Israel
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81
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Suryanarayana SM, Hellgren Kotaleski J, Grillner S, Gurney KN. Roles for globus pallidus externa revealed in a computational model of action selection in the basal ganglia. Neural Netw 2018; 109:113-136. [PMID: 30414556 DOI: 10.1016/j.neunet.2018.10.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/28/2018] [Accepted: 10/09/2018] [Indexed: 01/12/2023]
Abstract
The basal ganglia are considered vital to action selection - a hypothesis supported by several biologically plausible computational models. Of the several subnuclei of the basal ganglia, the globus pallidus externa (GPe) has been thought of largely as a relay nucleus, and its intrinsic connectivity has not been incorporated in significant detail, in any model thus far. Here, we incorporate newly revealed subgroups of neurons within the GPe into an existing computational model of the basal ganglia, and investigate their role in action selection. Three main results ensued. First, using previously used metrics for selection, the new extended connectivity improved the action selection performance of the model. Second, low frequency theta oscillations were observed in the subpopulation of the GPe (the TA or 'arkypallidal' neurons) which project exclusively to the striatum. These oscillations were suppressed by increased dopamine activity - revealing a possible link with symptoms of Parkinson's disease. Third, a new phenomenon was observed in which the usual monotonic relationship between input to the basal ganglia and its output within an action 'channel' was, under some circumstances, reversed. Thus, at high levels of input, further increase of this input to the channel could cause an increase of the corresponding output rather than the more usually observed decrease. Moreover, this phenomenon was associated with the prevention of multiple channel selection, thereby assisting in optimal action selection. Examination of the mechanistic origin of our results showed the so-called 'prototypical' GPe neurons to be the principal subpopulation influencing action selection. They control the striatum via the arkypallidal neurons and are also able to regulate the output nuclei directly. Taken together, our results highlight the role of the GPe as a major control hub of the basal ganglia, and provide a mechanistic account for its control function.
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Affiliation(s)
| | - Jeanette Hellgren Kotaleski
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Science for Life Laboratory, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm, Sweden.
| | - Sten Grillner
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| | - Kevin N Gurney
- Department of Psychology, University of Sheffield, Sheffield, UK.
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82
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Grewal SS, Holanda VM, Middlebrooks EH. Corticopallidal Connectome of the Globus Pallidus Externus in Humans: An Exploratory Study of Structural Connectivity Using Probabilistic Diffusion Tractography. AJNR Am J Neuroradiol 2018; 39:2120-2125. [PMID: 30262639 DOI: 10.3174/ajnr.a5816] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 08/07/2018] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND PURPOSE Electrophysiologic abnormalities of the globus pallidus externus have been shown in several disease processes including Parkinson disease, dystonia, and Huntington disease. However, the connectivity, nuclear structure, and function of the globus pallidus externus are still not well-understood. Increasing evidence for the existence of direct corticopallidal connections challenges traditional understanding of the connectivity of the globus pallidus externus; nevertheless, these corticopallidal connections have yet to be fully characterized in humans. The objective of this study was to assess the corticopallidal connections of the globus pallidus externus by means of probabilistic diffusion-weighted MR imaging tractography using high-resolution, multishell data. MATERIALS AND METHODS Imaging data from the open-access Human Connectome Project data base were used to perform probabilistic tractography between the globus pallidus externus and the cerebral cortex using 34 distinct cortical regions. Group averages were calculated for normalized percentages of tracts reaching each of the cortical targets, and side-to-side comparison was made. RESULTS Cortical connectivity was demonstrated between the globus pallidus externus and multiple cortical regions, including direct connection to putative sensorimotor, associative, and limbic areas. Connectivity patterns were not significantly different between the right and left hemispheres with the exception of the frontal pole, which showed a greater number of connections on the right (P = .004). CONCLUSIONS Our in vivo study of the human globus pallidus externus using probabilistic tractography supports the existence of extensive corticopallidal connections and a tripartite functional division, as found in animal studies. A better understanding of the connectivity of the globus pallidus externus may help to understand its function and elucidate the effects of programming the higher contacts in pallidal deep brain stimulation.
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Affiliation(s)
- S S Grewal
- From the Departments of Neurosurgery (S.S.G., E.H.M.)
| | - V M Holanda
- Center of Neurology and Neurosurgery Associates (V.M.H.), BP-A Beneficência Portuguesa de São Paulo, São Paulo, Brazil
| | - E H Middlebrooks
- From the Departments of Neurosurgery (S.S.G., E.H.M.) .,Radiology (E.H.M.), Mayo Clinic, Jacksonville, Florida
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83
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Abrahao KP, Lovinger DM. Classification of GABAergic neuron subtypes from the globus pallidus using wild-type and transgenic mice. J Physiol 2018; 596:4219-4235. [PMID: 29917235 PMCID: PMC6117588 DOI: 10.1113/jp276079] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/07/2018] [Indexed: 01/08/2023] Open
Abstract
KEY POINTS Classifying different subtypes of neurons in deep brain structures is a challenge and is crucial to better understand brain function. Understanding the diversity of neurons in the globus pallidus (GP), a brain region positioned to influence afferent and efferent information processing within basal ganglia, could help to explain a variety of brain functions. We present a classification of neurons from the GP using electrophysiological data from wild-type mice and confirmation using transgenic mice. This work will help researchers to identify specific neuronal subsets in the GP of wild-type mice when transgenic mice with labelled neurons are lacking. ABSTRACT Classification of the extensive neuronal diversity in the brain is fundamental for neuroscience. The globus pallidus external segment (GPe), also referred to as the globus pallidus in rodents, is a large nucleus located in the core of the basal ganglia whose circuitry is implicated in action control, decision-making and reward. Although considerable progress has been made in characterizing different GPe neuronal subtypes, no work has directly attempted to characterize these neurons in non-transgenic mice. Here, we provide data showing the degree of overlap in expression of neuronal PAS domain protein (Npas1), LIM homeobox 6 (Lhx6), parvalbumin (PV) and transcription factor FoxP2 biomarkers in mouse GPe neurons. We used an unbiased statistical method to classify neurons based on electrophysiological properties from nearly 200 neurons from C57BL/6J mice. In addition, we examined the subregion distribution of the neuronal subtypes. Cluster analysis using firing rate and hyperpolarization-induced membrane potential sag variables revealed three distinct neuronal clusters: type 1, characterized by low firing rate and small sag potential; type 2, with low firing rate and larger sag potential; and type 3, with high firing rate and small sag potential. We used other electrophysiological variables and data from marker-expressing neurons to evaluate the clusters. We propose that the GPe GABAergic neurons should be classified into three subgroups: arkypallidal, low-firing prototypical and high-firing prototypical neurons. This work will help researchers identify GPe neuron subtypes when transgenic mice with labelled neurons cannot be used.
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Affiliation(s)
- Karina P. Abrahao
- Laboratory for Integrative Neuroscience, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and AlcoholismNational Institutes of HealthBethesdaMDUSA
| | - David M. Lovinger
- Laboratory for Integrative Neuroscience, Division of Intramural Clinical and Biological Research, National Institute on Alcohol Abuse and AlcoholismNational Institutes of HealthBethesdaMDUSA
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84
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Tian J, Yan Y, Xi W, Zhou R, Lou H, Duan S, Chen JF, Zhang B. Optogenetic Stimulation of GABAergic Neurons in the Globus Pallidus Produces Hyperkinesia. Front Behav Neurosci 2018; 12:185. [PMID: 30210317 PMCID: PMC6119815 DOI: 10.3389/fnbeh.2018.00185] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Accepted: 08/02/2018] [Indexed: 01/19/2023] Open
Abstract
The globus pallidus (GP) is emerging as a critical locus of basal ganglia control of motor activity, but the exact role of GABAergic GP neurons remain to be defined. By targeted expression of channelrhodopsin 2 (ChR2) in GABAergic neurons using the VGAT-ChR2-EYFP transgenic mice, we showed that optogenetic stimulation of GABAergic neurons in the right GP produced hyperkinesia. Optogenetic stimulation of GABAergic GP neurons increased c-Fos-positive cells in GP, M1 cortex, and caudate-putamen (CPu), and decreased c-Fos-positive cells in entopeduncular nucleus (EPN), compared to the contralateral hemisphere. In agreement with the canonical basal ganglia model. Furthermore, we delivered AAV-CaMKIIα-ChR2-mCherry virus to the excitatory neurons of the subthalamic nucleus (STN) and selectively stimulated glutamatergic afferent fibers from the STN onto the GP. This optogenetic stimulation produced abnormal movements, similar to the behaviors that observed in the VGAT-ChR2-EYFP transgenic mice. Meanwhile, we found that the c-Fos expression pattern in the GP, M1, STN, EPN, and CPu produced by optogenetic activation of glutamatergic afferent fibers from the STN in GP was similar to the c-Fos expression pattern in the VGAT-ChR2-EYFP transgenic mice. Taken together, our results suggest that excess GP GABAergic neurons activity could be the neural substrate of abnormal involuntary movements in hyperkinetic movement disorders. The neural circuitry underlying the abnormal involuntary movements is associated with excessive GP, M1, CPu activity, and reduced EPN activity. Inhibition of GP GABAergic neurons represents new treatment targets for hyperkinetic movement disorder.
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Affiliation(s)
- Jun Tian
- Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yaping Yan
- Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Wang Xi
- Department of Neurobiology, School of Medicine, Zhejiang University, Hangzhou, China
| | - Rui Zhou
- Department of Neurobiology, School of Medicine, Zhejiang University, Hangzhou, China
| | - Huifang Lou
- Department of Neurobiology, School of Medicine, Zhejiang University, Hangzhou, China
| | - Shumin Duan
- Department of Neurobiology, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jiang Fan Chen
- School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
| | - Baorong Zhang
- Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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85
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Hunt AJ, Dasgupta R, Rajamanickam S, Jiang Z, Beierlein M, Chan CS, Justice NJ. Paraventricular hypothalamic and amygdalar CRF neurons synapse in the external globus pallidus. Brain Struct Funct 2018; 223:2685-2698. [PMID: 29569009 PMCID: PMC5997534 DOI: 10.1007/s00429-018-1652-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 03/16/2018] [Indexed: 12/16/2022]
Abstract
Stress evokes directed movement to escape or hide from potential danger. Corticotropin-releasing factor (CRF) neurons are highly activated by stress; however, it remains unclear how this activity participates in stress-evoked movement. The external globus pallidus (GPe) expresses high levels of the primary receptor for CRF, CRFR1, suggesting the GPe may serve as an entry point for stress-relevant information to reach basal ganglia circuits, which ultimately gate motor output. Indeed, projections from CRF neurons are present within the GPe, making direct contact with CRFR1-positive neurons. CRFR1 expression is heterogenous in the GPe; prototypic GPe neurons selectively express CRFR1, while arkypallidal neurons do not. Moreover, CRFR1-positive GPe neurons are excited by CRF via activation of CRFR1, while nearby CRFR1-negative neurons do not respond to CRF. Using monosynaptic rabies viral tracing techniques, we show that CRF neurons in the stress-activated paraventricular nucleus of the hypothalamus (PVN), central nucleus of the amygdala (CeA), and bed nucleus of the stria terminalis (BST) make synaptic connections with CRFR1-positive neurons in the GPe an unprecedented circuit connecting the limbic system with the basal ganglia. CRF neurons also make synapses on Npas1 neurons, although the majority of Npas1 neurons are arkypallidal and do not express CRFR1. Interestingly, prototypic and arkypallidal neurons receive different patterns of innervation from CRF-rich nuclei. Hypothalamic CRF neurons preferentially target prototypic neurons, while amygdalar CRF neurons preferentially target arkypallidal neurons, suggesting that these two inputs to the GPe may have different impacts on GPe output. Together, these data describe a novel neural circuit by which stress-relevant information carried by the limbic system signals in the GPe via CRF to influence motor output.
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Affiliation(s)
- Albert J Hunt
- The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, Center for Metabolic and Degenerative Diseases, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
- Graduate Program in Neuroscience, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, 77030, USA
| | - Rajan Dasgupta
- Department of Neurobiology and Anatomy, McGovern Medical School, Houston, TX, 77030, USA
- Graduate Program in Neuroscience, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, 77030, USA
| | - Shivakumar Rajamanickam
- The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, Center for Metabolic and Degenerative Diseases, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Zhiying Jiang
- The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, Center for Metabolic and Degenerative Diseases, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Michael Beierlein
- Department of Neurobiology and Anatomy, McGovern Medical School, Houston, TX, 77030, USA
- Graduate Program in Neuroscience, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, 77030, USA
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Nicholas J Justice
- The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, Center for Metabolic and Degenerative Diseases, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.
- Graduate Program in Neuroscience, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, 77030, USA.
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86
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Lewis MM, Sterling NW, Du G, Lee EY, Shyu G, Goldenberg M, Allen T, Stetter C, Kong L, Snipes SA, Jones BC, Chen H, Mailman RB, Huang X. Lateralized Basal Ganglia Vulnerability to Pesticide Exposure in Asymptomatic Agricultural Workers. Toxicol Sci 2018. [PMID: 28633499 DOI: 10.1093/toxsci/kfx126] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Pesticide exposure is linked to Parkinson's disease, a neurodegenerative disorder marked by dopamine cell loss in the substantia nigra of the basal ganglia (BG) that often presents asymmetrically. We previously reported that pesticide-exposed agricultural workers (AW) have nigral diffusion tensor imaging (DTI) changes. The current study sought to confirm this finding, and explore its hemisphere and regional specificity within BG structures using an independent sample population. Pesticide exposure history, standard neurological exam, high-resolution magnetic resonance imaging (T1/T2-weighted and DTI), and [123I]ioflupane SPECT images (to quantify striatal dopamine transporters) were obtained from 20 AW with chronic pesticide exposure and 11 controls. Based on median cumulative days of pesticide exposure, AW were subdivided into high (AWHi, n = 10) and low (AWLo, n = 10) exposure groups. BG (nigra, putamen, caudate, and globus pallidus [GP]) fractional anisotropy (FA), mean diffusivity (MD), and striatal [123I]ioflupane binding in each hemisphere were quantified, and compared across exposure groups using analysis of variance. Left, but not right, nigral and GP FA were significantly lower in AW compared with controls (p's < .029). None of the striatal (putamen and caudate) DTI or [123I]ioflupane binding measurements differed between AW and controls. Subgroup analyses indicated that significant left nigral and GP DTI changes were present only in the AWHi (p ≤ .037) but not the AWLo subgroup. AW, especially those with higher pesticide exposure history, demonstrate lateralized microstructural changes in the nigra and GP, whereas striatal areas appear relatively unaffected. Future studies should elucidate how environmental toxicants cause differential lateralized- and regionally specific brain vulnerability.
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Affiliation(s)
| | | | | | | | | | | | - Thomas Allen
- Department of Radiology, and Department of Public Health Sciences, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
| | - Christy Stetter
- Department of Radiology, and Department of Public Health Sciences, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
| | - Lan Kong
- Department of Radiology, and Department of Public Health Sciences, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
| | - Shedra Amy Snipes
- Department of Biobehavioral Health, Pennsylvania State University University Park, Pennsylvania 16802
| | - Byron C Jones
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Honglei Chen
- Department of Epidemiology and Biostatistics, Michigan State University, East Lansing, Michigan 48824
| | | | - Xuemei Huang
- Department of Neurology.,Department of Pharmacology.,Department of Radiology, and Department of Public Health Sciences, Pennsylvania State University-Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033
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87
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Distinct Anatomical Connectivity Patterns Differentiate Subdivisions of the Nonlemniscal Auditory Thalamus in Mice. Cereb Cortex 2018; 29:2437-2454. [DOI: 10.1093/cercor/bhy115] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/04/2018] [Indexed: 11/14/2022] Open
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88
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Mutant Huntingtin Causes a Selective Decrease in the Expression of Synaptic Vesicle Protein 2C. Neurosci Bull 2018; 34:747-758. [PMID: 29713895 DOI: 10.1007/s12264-018-0230-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 03/24/2018] [Indexed: 12/11/2022] Open
Abstract
Huntington's disease (HD) is a neurodegenerative disease caused by a polyglutamine expansion in the huntingtin (Htt) protein. Mutant Htt causes synaptic transmission dysfunctions by interfering in the expression of synaptic proteins, leading to early HD symptoms. Synaptic vesicle proteins 2 (SV2s), a family of synaptic vesicle proteins including 3 members, SV2A, SV2B, and SV2C, plays important roles in synaptic physiology. Here, we investigated whether the expression of SV2s is affected by mutant Htt in the brains of HD transgenic (TG) mice and Neuro2a mouse neuroblastoma cells (N2a cells) expressing mutant Htt. Western blot analysis showed that the protein levels of SV2A and SV2B were not significantly changed in the brains of HD TG mice expressing mutant Htt with 82 glutamine repeats. However, in the TG mouse brain there was a dramatic decrease in the protein level of SV2C, which has a restricted distribution pattern in regions particularly vulnerable in HD. Immunostaining revealed that the immunoreactivity of SV2C was progressively weakened in the basal ganglia and hippocampus of TG mice. RT-PCR demonstrated that the mRNA level of SV2C progressively declined in the TG mouse brain without detectable changes in the mRNA levels of SV2A and SV2B, indicating that mutant Htt selectively inhibits the transcriptional expression of SV2C. Furthermore, we found that only SV2C expression was progressively inhibited in N2a cells expressing a mutant Htt containing 120 glutamine repeats. These findings suggest that the synaptic dysfunction in HD results from the mutant Htt-mediated inhibition of SV2C transcriptional expression. These data also imply that the restricted distribution and decreased expression of SV2C contribute to the brain region-selective pathology of HD.
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89
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Garret M, Du Z, Chazalon M, Cho YH, Baufreton J. Alteration of GABAergic neurotransmission in Huntington's disease. CNS Neurosci Ther 2018; 24:292-300. [PMID: 29464851 DOI: 10.1111/cns.12826] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 01/23/2018] [Accepted: 01/26/2018] [Indexed: 12/16/2022] Open
Abstract
Hereditary Huntington's disease (HD) is characterized by cell dysfunction and death in the brain, leading to progressive cognitive, psychiatric, and motor impairments. Despite molecular and cellular descriptions of the effects of the HD mutation, no effective pharmacological treatment is yet available. In addition to well-established alterations of glutamatergic and dopaminergic neurotransmitter systems, it is becoming clear that the GABAergic systems are also impaired in HD. GABA is the major inhibitory neurotransmitter in the brain, and GABAergic neurotransmission has been postulated to be modified in many neurological and psychiatric diseases. In addition, GABAergic neurotransmission is the target of many drugs that are in wide clinical use. Here, we summarize data demonstrating the occurrence of alterations of GABAergic markers in the brain of HD carriers as well as in rodent models of the disease. In particular, we pinpoint HD-related changes in the expression of GABAA receptors (GABAA Rs). On the basis that a novel GABA pharmacology of GABAA Rs established with more selective drugs is emerging, we argue that clinical treatments acting specifically on GABAergic neurotransmission may be an appropriate strategy for improving symptoms linked to the HD mutation.
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Affiliation(s)
- Maurice Garret
- Université de Bordeaux, INCIA, UMR 5287, Bordeaux, France.,CNRS, INCIA, UMR 5287, Bordeaux, France
| | - Zhuowei Du
- Université de Bordeaux, INCIA, UMR 5287, Bordeaux, France.,CNRS, INCIA, UMR 5287, Bordeaux, France
| | - Marine Chazalon
- Institut des Maladies Neurodégénératives, Université de Bordeaux, UMR 5293, Bordeaux, France.,Institut des Maladies Neurodégénératives, CNRS, UMR 5293, Bordeaux, France
| | - Yoon H Cho
- Université de Bordeaux, INCIA, UMR 5287, Bordeaux, France.,CNRS, INCIA, UMR 5287, Bordeaux, France
| | - Jérôme Baufreton
- Institut des Maladies Neurodégénératives, Université de Bordeaux, UMR 5293, Bordeaux, France.,Institut des Maladies Neurodégénératives, CNRS, UMR 5293, Bordeaux, France
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90
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Lindroos R, Dorst MC, Du K, Filipović M, Keller D, Ketzef M, Kozlov AK, Kumar A, Lindahl M, Nair AG, Pérez-Fernández J, Grillner S, Silberberg G, Hellgren Kotaleski J. Basal Ganglia Neuromodulation Over Multiple Temporal and Structural Scales-Simulations of Direct Pathway MSNs Investigate the Fast Onset of Dopaminergic Effects and Predict the Role of Kv4.2. Front Neural Circuits 2018; 12:3. [PMID: 29467627 PMCID: PMC5808142 DOI: 10.3389/fncir.2018.00003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 01/09/2018] [Indexed: 12/16/2022] Open
Abstract
The basal ganglia are involved in the motivational and habitual control of motor and cognitive behaviors. Striatum, the largest basal ganglia input stage, integrates cortical and thalamic inputs in functionally segregated cortico-basal ganglia-thalamic loops, and in addition the basal ganglia output nuclei control targets in the brainstem. Striatal function depends on the balance between the direct pathway medium spiny neurons (D1-MSNs) that express D1 dopamine receptors and the indirect pathway MSNs that express D2 dopamine receptors. The striatal microstructure is also divided into striosomes and matrix compartments, based on the differential expression of several proteins. Dopaminergic afferents from the midbrain and local cholinergic interneurons play crucial roles for basal ganglia function, and striatal signaling via the striosomes in turn regulates the midbrain dopaminergic system directly and via the lateral habenula. Consequently, abnormal functions of the basal ganglia neuromodulatory system underlie many neurological and psychiatric disorders. Neuromodulation acts on multiple structural levels, ranging from the subcellular level to behavior, both in health and disease. For example, neuromodulation affects membrane excitability and controls synaptic plasticity and thus learning in the basal ganglia. However, it is not clear on what time scales these different effects are implemented. Phosphorylation of ion channels and the resulting membrane effects are typically studied over minutes while it has been shown that neuromodulation can affect behavior within a few hundred milliseconds. So how do these seemingly contradictory effects fit together? Here we first briefly review neuromodulation of the basal ganglia, with a focus on dopamine. We furthermore use biophysically detailed multi-compartmental models to integrate experimental data regarding dopaminergic effects on individual membrane conductances with the aim to explain the resulting cellular level dopaminergic effects. In particular we predict dopaminergic effects on Kv4.2 in D1-MSNs. Finally, we also explore dynamical aspects of the onset of neuromodulation effects in multi-scale computational models combining biochemical signaling cascades and multi-compartmental neuron models.
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Affiliation(s)
- Robert Lindroos
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
| | - Matthijs C. Dorst
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
| | - Kai Du
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
| | - Marko Filipović
- Bernstein Center Freiburg, University of Freiburg, Freiburg im Breisgau, Germany
| | - Daniel Keller
- Blue Brain Project, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Maya Ketzef
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
| | - Alexander K. Kozlov
- Science for Life Laboratory, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Solna, Sweden
| | - Arvind Kumar
- Bernstein Center Freiburg, University of Freiburg, Freiburg im Breisgau, Germany
- Department Computational Science and Technology, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Mikael Lindahl
- Science for Life Laboratory, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Solna, Sweden
| | - Anu G. Nair
- Science for Life Laboratory, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Solna, Sweden
| | - Juan Pérez-Fernández
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
| | - Sten Grillner
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
| | - Gilad Silberberg
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
| | - Jeanette Hellgren Kotaleski
- Department of Neuroscience, Nobel Institute for Neurophysiology, Stockholm, Sweden
- Science for Life Laboratory, School of Electrical Engineering and Computer Science, KTH Royal Institute of Technology, Solna, Sweden
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91
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West TO, Berthouze L, Halliday DM, Litvak V, Sharott A, Magill PJ, Farmer SF. Propagation of beta/gamma rhythms in the cortico-basal ganglia circuits of the parkinsonian rat. J Neurophysiol 2018; 119:1608-1628. [PMID: 29357448 PMCID: PMC6008089 DOI: 10.1152/jn.00629.2017] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Much of the motor impairment associated with Parkinson’s disease is thought to arise from pathological activity in the networks formed by the basal ganglia (BG) and motor cortex. To evaluate several hypotheses proposed to explain the emergence of pathological oscillations in parkinsonism, we investigated changes to the directed connectivity in BG networks following dopamine depletion. We recorded local field potentials (LFPs) in the cortex and basal ganglia of rats rendered parkinsonian by injection of 6-hydroxydopamine (6-OHDA) and in dopamine-intact controls. We performed systematic analyses of the networks using a novel tool for estimation of directed interactions (nonparametric directionality, NPD). We used a “conditioned” version of the NPD analysis that reveals the dependence of the correlation between two signals on a third reference signal. We find evidence of the dopamine dependency of both low-beta (14–20 Hz) and high-beta/low-gamma (20–40 Hz) directed network interactions. Notably, 6-OHDA lesions were associated with enhancement of the cortical “hyperdirect” connection to the subthalamic nucleus (STN) and its feedback to the cortex and striatum. We find that pathological beta synchronization resulting from 6-OHDA lesioning is widely distributed across the network and cannot be located to any individual structure. Furthermore, we provide evidence that high-beta/gamma oscillations propagate through the striatum in a pathway that is independent of STN. Rhythms at high beta/gamma show susceptibility to conditioning that indicates a hierarchical organization compared with those at low beta. These results further inform our understanding of the substrates for pathological rhythms in salient brain networks in parkinsonism. NEW & NOTEWORTHY We present a novel analysis of electrophysiological recordings in the cortico-basal ganglia network with the aim of evaluating several hypotheses concerning the origins of abnormal brain rhythms associated with Parkinson’s disease. We present evidence for changes in the directed connections within the network following chronic dopamine depletion in rodents. These findings speak to the plausibility of a “short-circuiting” of the network that gives rise to the conditions from which pathological synchronization may arise.
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Affiliation(s)
- Timothy O West
- Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), Department of Physics and Astronomy, University College London , London , United Kingdom.,Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London , London , United Kingdom
| | - Luc Berthouze
- Centre for Computational Neuroscience and Robotics, University of Sussex , Falmer , United Kingdom.,UCL Great Ormond Street Institute of Child Health , London , United Kingdom
| | - David M Halliday
- Department of Electronic Engineering, University of York , York , United Kingdom
| | - Vladimir Litvak
- Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London , London , United Kingdom
| | - Andrew Sharott
- Medical Research Council Brain Network Dynamics Unit, University of Oxford , Oxford , United Kingdom
| | - Peter J Magill
- Medical Research Council Brain Network Dynamics Unit, University of Oxford , Oxford , United Kingdom.,Oxford Parkinson's Disease Centre, University of Oxford , Oxford , United Kingdom
| | - Simon F Farmer
- Department of Neurology, National Hospital for Neurology & Neurosurgery , London , United Kingdom.,Sobell Department of Motor Neuroscience and Movement Disorders, Institute of Neurology, University College London , London , United Kingdom
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92
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Blunted mGluR Activation Disinhibits Striatopallidal Transmission in Parkinsonian Mice. Cell Rep 2017; 17:2431-2444. [PMID: 27880915 PMCID: PMC5489133 DOI: 10.1016/j.celrep.2016.10.087] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 09/07/2016] [Accepted: 10/27/2016] [Indexed: 01/10/2023] Open
Abstract
The prevailing circuit model predicts that hyperactivity of the striatopallidal pathway and subsequently increased inhibition of external globus pallidus (GPe) neurons lead to the hypokinetic symptoms of Parkinson's disease (PD). It is believed that hyperactivity of the striatopallidal pathway is due to inactivity of dopamine receptors on the somatodendritic membrane of striatopallidal neurons, but the exact cellular underpinnings remain unclear. In this study, we show that mouse GPe astrocytes critically control ambient glutamate level, which in turn gates striatopallidal transmission via the activation of presynaptic metabotropic glutamate receptors. This presynaptic inhibition of striatopallidal transmission is diminished after the chronic loss of dopamine. Elevation of intracellular glutamate content in astrocytes restores the proper regulation of the striatopallidal input in PD models. These findings argue that astrocytes are key regulators of the striatopallidal synapse. Targeting this cell class may serve as an alternative therapeutic strategy for PD.
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93
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Diao HL, Xue Y, Han XH, Wang SY, Liu C, Chen WF, Chen L. Adenosine A 2A Receptor Modulates the Activity of Globus Pallidus Neurons in Rats. Front Physiol 2017; 8:897. [PMID: 29163226 PMCID: PMC5682020 DOI: 10.3389/fphys.2017.00897] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 10/24/2017] [Indexed: 12/23/2022] Open
Abstract
The globus pallidus is a central nucleus in the basal ganglia motor control circuit. Morphological studies have revealed the expression of adenosine A2A receptors in the globus pallidus. To determine the modulation of adenosine A2A receptors on the activity of pallidal neurons in both normal and parkinsonian rats, in vivo electrophysiological and behavioral tests were performed in the present study. The extracellular single unit recordings showed that micro-pressure administration of adenosine A2A receptor agonist, CGS21680, regulated the pallidal firing activity. GABAergic neurotransmission was involved in CGS21680-induced modulation of pallidal neurons via a PKA pathway. Furthermore, application of two adenosine A2A receptor antagonists, KW6002 or SCH442416, mainly increased the spontaneous firing of pallidal neurons, suggesting that endogenous adenosine system modulates the activity of pallidal neurons through adenosine A2A receptors. Finally, elevated body swing test (EBST) showed that intrapallidal microinjection of adenosine A2A receptor agonist/antagonist induced ipsilateral/contralateral-biased swing, respectively. In addition, the electrophysiological and behavioral findings also revealed that activation of dopamine D2 receptors by quinpirole strengthened KW6002/SCH442416-induced excitation of pallidal activity. Co-application of quinpirole with KW6002 or SCH442416 alleviated biased swing in hemi-parkinsonian rats. Based on the present findings, we concluded that pallidal adenosine A2A receptors may be potentially useful in the treatment of Parkinson's disease.
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Affiliation(s)
- Hui-Ling Diao
- Department of Physiology, Qingdao University, Qingdao, China.,Department of Physiology, Binzhou Medical University, Yantai, China
| | - Yan Xue
- Department of Physiology, Qingdao University, Qingdao, China
| | - Xiao-Hua Han
- Department of Physiology, Qingdao University, Qingdao, China
| | - Shuang-Yan Wang
- Department of Physiology, Qingdao University, Qingdao, China.,Department of Anatomy, Qingdao University, Qingdao, China
| | - Cui Liu
- Department of Physiology, Qingdao University, Qingdao, China
| | - Wen-Fang Chen
- Department of Physiology, Qingdao University, Qingdao, China
| | - Lei Chen
- Department of Physiology, Qingdao University, Qingdao, China
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94
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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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95
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Rahayel S, Postuma RB, Montplaisir J, Bedetti C, Brambati S, Carrier J, Monchi O, Bourgouin PA, Gaubert M, Gagnon JF. Abnormal Gray Matter Shape, Thickness, and Volume in the Motor Cortico-Subcortical Loop in Idiopathic Rapid Eye Movement Sleep Behavior Disorder: Association with Clinical and Motor Features. Cereb Cortex 2017; 28:658-671. [DOI: 10.1093/cercor/bhx137] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Indexed: 11/13/2022] Open
Affiliation(s)
- Shady Rahayel
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Department of Psychology, Université du Québec à Montréal, Montreal, Quebec H2X 3P2, Canada
| | - Ronald B Postuma
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Department of Neurology, Montreal General Hospital, Montreal, Quebec H3G 1A4, Canada
| | - Jacques Montplaisir
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Department of Psychiatry, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
| | - Christophe Bedetti
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Research Centre, Institut universitaire de gériatrie de Montréal, Montreal, Quebec H3W 1W5, Canada
| | - Simona Brambati
- Research Centre, Institut universitaire de gériatrie de Montréal, Montreal, Quebec H3W 1W5, Canada
- Department of Psychology, Université de Montréal, Montreal, Quebec H2V 2S9, Canada
| | - Julie Carrier
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Research Centre, Institut universitaire de gériatrie de Montréal, Montreal, Quebec H3W 1W5, Canada
- Department of Psychology, Université de Montréal, Montreal, Quebec H2V 2S9, Canada
| | - Oury Monchi
- Department of Neurology, Montreal General Hospital, Montreal, Quebec H3G 1A4, Canada
- Research Centre, Institut universitaire de gériatrie de Montréal, Montreal, Quebec H3W 1W5, Canada
- Department of Radiology, Radio-Oncology, and Nuclear Medicine, Université de Montréal, Montreal, Quebec H3T 1A4, Canada
- Departments of Clinical Neurosciences and Radiology, and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Pierre-Alexandre Bourgouin
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Department of Psychology, Université du Québec à Montréal, Montreal, Quebec H2X 3P2, Canada
| | - Malo Gaubert
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Department of Psychology, Université du Québec à Montréal, Montreal, Quebec H2X 3P2, Canada
| | - Jean-François Gagnon
- Centre for Advanced Research in Sleep Medicine, Hôpital du Sacré-Cœur de Montréal, Montreal, Quebec H4J 1C5, Canada
- Department of Psychology, Université du Québec à Montréal, Montreal, Quebec H2X 3P2, Canada
- Research Centre, Institut universitaire de gériatrie de Montréal, Montreal, Quebec H3W 1W5, Canada
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96
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Mastro KJ, Zitelli KT, Willard AM, Leblanc KH, Kravitz AV, Gittis AH. Cell-specific pallidal intervention induces long-lasting motor recovery in dopamine-depleted mice. Nat Neurosci 2017; 20:815-823. [PMID: 28481350 PMCID: PMC5546121 DOI: 10.1038/nn.4559] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 04/05/2017] [Indexed: 12/16/2022]
Abstract
The identification of distinct cell types in the basal ganglia has been critical to our understanding of basal ganglia function and the treatment of neurological disorders. The external globus pallidus (GPe) is a key contributor to motor suppressing pathways in the basal ganglia, yet its neuronal heterogeneity has remained an untapped resource for therapeutic interventions. Here we demonstrate that optogenetic interventions that dissociate the activity of two neuronal populations in the GPe, elevating the activity of parvalbumin (PV)-expressing GPe neurons over that of Lim homeobox 6 (Lhx6)-expressing GPe neurons, restores movement in dopamine-depleted mice and attenuates pathological activity of basal ganglia output neurons for hours beyond stimulation. These results establish the utility of cell-specific interventions in the GPe to target functionally distinct pathways, with the potential to induce long-lasting recovery of movement despite the continued absence of dopamine.
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Affiliation(s)
- Kevin J Mastro
- Center for Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Kevin T Zitelli
- Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Amanda M Willard
- Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Kimberly H Leblanc
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Alexxai V Kravitz
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Aryn H Gittis
- Biological Sciences and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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97
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Ethanol-Sensitive Pacemaker Neurons in the Mouse External Globus Pallidus. Neuropsychopharmacology 2017; 42:1070-1081. [PMID: 27827370 PMCID: PMC5506786 DOI: 10.1038/npp.2016.251] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 10/26/2016] [Accepted: 10/27/2016] [Indexed: 11/27/2022]
Abstract
Although ethanol is one of the most widely used drugs, we still lack a full understanding of which neuronal subtypes are affected by this drug. Pacemaker neurons exert powerful control over brain circuit function, but little is known about ethanol effects on these types of neurons. Neurons in the external globus pallidus (GPe) generate pacemaker activity that controls basal ganglia, circuitry associated with habitual and compulsive drug use. We performed patch-clamp recordings from GPe neurons and found that bath application of ethanol dose-dependently decreased the firing rate of low-frequency GPe neurons, but did not alter the firing of high-frequency neurons. GABA or glutamate receptor antagonists did not block the ethanol effect. The GPe is comprised of a heterogeneous population of neurons. We used Lhx6-EGFP and Npas1-tdTm mice strains to identify low-frequency neurons. Lhx6 and Npas1 neurons exhibited decreased firing with ethanol, but only Npas1 neurons were sensitive to 10 mM ethanol. Large-conductance voltage and Ca2+-activated K+ (BK) channel have a key role in the ethanol effect on GPe neurons, as the application of BK channel inhibitors blocked the ethanol-induced firing decrease. Ethanol also increased BK channel open probability measured in single-channel recordings from Npas1-tdTm neurons. In addition, in vivo electrophysiological recordings from GPe showed that ethanol decreased the firing of a large subset of low-frequency neurons. These findings indicate how selectivity of ethanol effects on pacemaker neurons can occur, and enhance our understanding of the mechanisms contributing to acute ethanol effects on the basal ganglia.
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98
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Wei W, Wang XJ. Inhibitory Control in the Cortico-Basal Ganglia-Thalamocortical Loop: Complex Regulation and Interplay with Memory and Decision Processes. Neuron 2016; 92:1093-1105. [PMID: 27866799 PMCID: PMC5193098 DOI: 10.1016/j.neuron.2016.10.031] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 09/12/2016] [Accepted: 10/12/2016] [Indexed: 01/25/2023]
Abstract
We developed a circuit model of spiking neurons that includes multiple pathways in the basal ganglia (BG) and is endowed with feedback mechanisms at three levels: cortical microcircuit, corticothalamic loop, and cortico-BG-thalamocortical system. We focused on executive control in a stop signal task, which is known to depend on BG across species. The model reproduces a range of experimental observations and shows that the newly discovered feedback projection from external globus pallidus to striatum is crucial for inhibitory control. Moreover, stopping process is enhanced by the cortico-subcortical reverberatory dynamics underlying persistent activity, establishing interdependence between working memory and inhibitory control. Surprisingly, the stop signal reaction time (SSRT) can be adjusted by weights of certain connections but is insensitive to other connections in this complex circuit, suggesting novel circuit-based intervention for inhibitory control deficits associated with mental illness. Our model provides a unified framework for inhibitory control, decision making, and working memory.
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Affiliation(s)
- Wei Wei
- Center for Neural Science, New York University, New York, NY 10003, USA
| | - Xiao-Jing Wang
- Center for Neural Science, New York University, New York, NY 10003, USA; NYU-ECNU Institute of Brain and Cognitive Science, NYU Shanghai, 200122 Shanghai, China.
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99
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Mahone EM, Crocetti D, Tochen L, Kline T, Mostofsky SH, Singer HS. Anomalous Putamen Volume in Children With Complex Motor Stereotypies. Pediatr Neurol 2016; 65:59-63. [PMID: 27751663 PMCID: PMC5124524 DOI: 10.1016/j.pediatrneurol.2016.08.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 08/24/2016] [Accepted: 08/25/2016] [Indexed: 12/27/2022]
Abstract
BACKGROUND Complex motor stereotypies in children are repetitive rhythmic movements that have a predictable pattern and location, seem purposeful, but serve no obvious function, tend to be prolonged, and stop with distraction, e.g., arm or hand flapping, waving. They occur in both "primary" (otherwise typically developing) and secondary conditions. These movements are best defined as habitual behaviors and therefore pathophysiologically hypothesized to reside in premotor to posterior putamen circuits. This study sought to clarify the underlying neurobiologic abnormality in children with primary complex motor stereotypies using structural neuroimaging, emphasizing brain regions hypothesized to underlie these atypical behaviors. METHODS High-resolution anatomic magnetic resonance images, acquired at 3.0 T, were analyzed in children aged eight to twelve years (20 with primary complex motor stereotypies and 20 typically developing). Frontal lobe subregions and striatal structures were delineated for analysis. RESULTS Significant reductions (P = 0.045) in the stereotypies group were identified in total putamen volume but not in caudate, nucleus accumbens, or frontal subregions. There were no group differences in total cerebral volume. CONCLUSIONS Findings of a smaller putamen provide preliminary evidence suggesting the potential involvement of the habitual pathway as the underlying anatomic site in primary complex motor stereotypies.
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Affiliation(s)
- E. Mark Mahone
- Kennedy Krieger Institute,Johns Hopkins University School of Medicine
| | | | | | - Tina Kline
- Johns Hopkins University School of Medicine
| | | | - Harvey S. Singer
- Kennedy Krieger Institute,Johns Hopkins University School of Medicine
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100
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Akopian G, Barry J, Cepeda C, Levine MS. Altered membrane properties and firing patterns of external globus pallidus neurons in the R6/2 mouse model of Huntington's disease. J Neurosci Res 2016; 94:1400-1410. [PMID: 27618125 DOI: 10.1002/jnr.23889] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/25/2016] [Accepted: 07/28/2016] [Indexed: 12/24/2022]
Abstract
In mouse models of Huntington's disease (HD), striatal neuron properties are significantly altered. These alterations predict changes in striatal output regions. However, little is known about alterations in those regions. The present study examines changes in passive and active membrane properties of neurons in the external globus pallidus (GPe), the first relay station of the indirect pathway, in the R6/2 mouse model of juvenile HD at presymptomatic (1 month) and symptomatic (2 month) stages. In GPe, two principal types of neurons can be distinguished based on firing properties and the presence (type A) or absence (type B) of Ih currents. In symptomatic animals (2 month), cell membrane capacitance and input resistance of type A neurons were increased compared with controls. In addition, action potential afterhyperpolarization amplitude was reduced. Although the spontaneous firing rate of GPe neurons was not different between control and R6/2 mice, the number of spikes evoked by depolarizing current pulses was significantly reduced in symptomatic R6/2 animals. In addition, these changes were accompanied by altered firing patterns evidenced by increased interspike interval variation and increased number of bursts. Blockade of GABAA receptors facilitated bursting activity in R6/2 mice but not in control littermates. Thus, alterations in firing patterns could be caused by changes in intrinsic membrane conductances and modulated by synaptic inputs. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Garnik Akopian
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, California
| | - Joshua Barry
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, California
| | - Carlos Cepeda
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, California
| | - Michael S Levine
- Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, California.
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