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Sumarac S, Youn J, Fearon C, Zivkovic L, Keerthi P, Flouty O, Popovic M, Hodaie M, Kalia S, Lozano A, Hutchison W, Fasano A, Milosevic L. Clinico-physiological correlates of Parkinson's disease from multi-resolution basal ganglia recordings. NPJ Parkinsons Dis 2024; 10:175. [PMID: 39261476 PMCID: PMC11391063 DOI: 10.1038/s41531-024-00773-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Accepted: 08/05/2024] [Indexed: 09/13/2024] Open
Abstract
Parkinson's disease (PD) has been associated with pathological neural activity within the basal ganglia. Herein, we analyzed resting-state single-neuron and local field potential (LFP) activities from people with PD who underwent awake deep brain stimulation surgery of the subthalamic nucleus (STN; n = 125) or globus pallidus internus (GPi; n = 44), and correlated rate-based and oscillatory features with UPDRSIII off-medication subscores. Rate-based single-neuron features did not correlate with PD symptoms. STN single-neuron and LFP low-beta (12-21 Hz) power and burst dynamics showed modest correlations with bradykinesia and rigidity severity, while STN spiketrain theta (4-8 Hz) power correlated modestly with tremor severity. GPi low- and high-beta (21-30 Hz) power and burst dynamics correlated moderately with bradykinesia and axial symptom severity. These findings suggest that elevated single-neuron and LFP oscillations may be linked to symptoms, though modest correlations imply that the pathophysiology of PD may extend beyond resting-state beta oscillations.
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Affiliation(s)
- Srdjan Sumarac
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Jinyoung Youn
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada
- Department of Neurology, University of Toronto, Toronto, ON, Canada
| | - Conor Fearon
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada
- Department of Neurology, University of Toronto, Toronto, ON, Canada
| | - Luka Zivkovic
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Prerana Keerthi
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Oliver Flouty
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Department of Neurosurgery and Brain Repair, University of South Florida, Tampa, FL, USA
| | - Milos Popovic
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- KITE, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Mojgan Hodaie
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Suneil Kalia
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- KITE, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Andres Lozano
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - William Hutchison
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Department of Surgery, University of Toronto, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
- Department of Physiology, University of Toronto, Toronto, ON, Canada
| | - Alfonso Fasano
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, Toronto, ON, Canada
- Department of Neurology, University of Toronto, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- KITE, University Health Network, Toronto, ON, Canada
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada
| | - Luka Milosevic
- Krembil Brain Institute, University Health Network, Toronto, ON, Canada.
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.
- KITE, University Health Network, Toronto, ON, Canada.
- Center for Advancing Neurotechnological Innovation to Application (CRANIA), Toronto, ON, Canada.
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2
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Lee H, Kim HF, Hikosaka O. Implication of regional selectivity of dopamine deficits in impaired suppressing of involuntary movements in Parkinson's disease. Neurosci Biobehav Rev 2024; 162:105719. [PMID: 38759470 PMCID: PMC11167649 DOI: 10.1016/j.neubiorev.2024.105719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 04/26/2024] [Accepted: 05/09/2024] [Indexed: 05/19/2024]
Abstract
To improve the initiation and speed of intended action, one of the crucial mechanisms is suppressing unwanted movements that interfere with goal-directed behavior, which is observed relatively aberrant in Parkinson's disease patients. Recent research has highlighted that dopamine deficits in Parkinson's disease predominantly occur in the caudal lateral part of the substantia nigra pars compacta (SNc) in human patients. We previously found two parallel circuits within the basal ganglia, primarily divided into circuits mediated by the rostral medial part and caudal lateral part of the SNc dopamine neurons. We have further discovered that the indirect pathway in caudal basal ganglia circuits, facilitated by the caudal lateral part of the SNc dopamine neurons, plays a critical role in suppressing unnecessary involuntary movements when animals perform voluntary goal-directed actions. We thus explored recent research in humans and non-human primates focusing on the distinct functions and networks of the caudal lateral part of the SNc dopamine neurons to elucidate the mechanisms involved in the impairment of suppressing involuntary movements in Parkinson's disease patients.
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Affiliation(s)
- Hyunchan Lee
- Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Bethesda, MD 20892-4435, USA.
| | - Hyoung F Kim
- School of Biological Sciences, College of Natural Sciences, Seoul National University (SNU), Seoul 08826, Republic of Korea
| | - Okihide Hikosaka
- Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Bethesda, MD 20892-4435, USA
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3
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Reiner A, Medina L, Abellan A, Deng Y, Toledo CA, Luksch H, Vega-Zuniga T, Riley NB, Hodos W, Karten HJ. Neurochemistry and circuit organization of the lateral spiriform nucleus of birds: A uniquely nonmammalian direct pathway component of the basal ganglia. J Comp Neurol 2024; 532:e25620. [PMID: 38733146 PMCID: PMC11090467 DOI: 10.1002/cne.25620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 03/24/2024] [Accepted: 04/16/2024] [Indexed: 05/13/2024]
Abstract
We used diverse methods to characterize the role of avian lateral spiriform nucleus (SpL) in basal ganglia motor function. Connectivity analysis showed that SpL receives input from globus pallidus (GP), and the intrapeduncular nucleus (INP) located ventromedial to GP, whose neurons express numerous striatal markers. SpL-projecting GP neurons were large and aspiny, while SpL-projecting INP neurons were medium sized and spiny. Connectivity analysis further showed that SpL receives inputs from subthalamic nucleus (STN) and substantia nigra pars reticulata (SNr), and that the SNr also receives inputs from GP, INP, and STN. Neurochemical analysis showed that SpL neurons express ENK, GAD, and a variety of pallidal neuron markers, and receive GABAergic terminals, some of which also contain DARPP32, consistent with GP pallidal and INP striatal inputs. Connectivity and neurochemical analysis showed that the SpL input to tectum prominently ends on GABAA receptor-enriched tectobulbar neurons. Behavioral studies showed that lesions of SpL impair visuomotor behaviors involving tracking and pecking moving targets. Our results suggest that SpL modulates brainstem-projecting tectobulbar neurons in a manner comparable to the demonstrated influence of GP internus on motor thalamus and of SNr on tectobulbar neurons in mammals. Given published data in amphibians and reptiles, it seems likely the SpL circuit represents a major direct pathway-type circuit by which the basal ganglia exerts its motor influence in nonmammalian tetrapods. The present studies also show that avian striatum is divided into three spatially segregated territories with differing connectivity, a medial striato-nigral territory, a dorsolateral striato-GP territory, and the ventrolateral INP motor territory.
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Affiliation(s)
- Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163
| | - Loreta Medina
- Department of Experimental Medicine, Universitat de Lleida, Lleida, Spain
- Laboratory of Evolutionary and Developmental Neurobiology, Lleida’s Institute for Biomedical Research-Dr. Pifarré Foundation (IRBLleida), Lleida, Catalonia, Spain
| | - Antonio Abellan
- Department of Experimental Medicine, Universitat de Lleida, Lleida, Spain
- Laboratory of Evolutionary and Developmental Neurobiology, Lleida’s Institute for Biomedical Research-Dr. Pifarré Foundation (IRBLleida), Lleida, Catalonia, Spain
| | - Yunping Deng
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, TN 38163
| | - Claudio A.B. Toledo
- Neuroscience Research Nucleus, Universidade Cidade de Sao Paulo, Sao Paulo 65057-420, Brazil
| | - Harald Luksch
- School of Life Sciences, Technische Universität München, Freising-Weihenstephan, Germany
| | - Tomas Vega-Zuniga
- School of Life Sciences, Technische Universität München, Freising-Weihenstephan, Germany
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Nell B. Riley
- Department of Psychology, University of Maryland College Park 20742-4411
| | - William Hodos
- Department of Psychology, University of Maryland College Park 20742-4411
| | - Harvey J. Karten
- Department of Neurosciences, University of California San Diego, San Diego, CA 92093-0608
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Knockout or Knock-in? A Truncated D2 Receptor Protein Is Expressed in the Brain of Functional D2 Receptor Knockout Mice. NEUROSCI 2021. [DOI: 10.3390/neurosci2020014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Null mice for the dopamine D2 receptor (D2R) have been instrumental in understanding the function of this protein. For our research, we obtained the functional D2R knockout mouse strain described initially in 1997. Surprisingly, our biochemical characterization showed that this mouse strain is not a true knockout. We determined by sequence analysis of the rapid 3′ amplification of cDNA ends that functional D2R knockout mice express transcripts that lack only the eighth exon. Furthermore, immunofluorescence assays showed a D2R-like protein in the brain of functional D2R knockout mice. We verified by immunofluorescence that the recombinant truncated D2R is expressed in HEK293T cells, showing intracellular localization, colocalizing in the Golgi apparatus and the endoplasmic reticulum, but with less presence in the Golgi apparatus compared to the native D2R. As previously reported, functional D2R knockout mice are hypoactive and insensitive to the D2R agonist quinpirole. Concordantly, microdialysis studies confirmed that functional D2R knockout mice have lower extracellular dopamine levels in the striatum than the native mice. In conclusion, functional D2R knockout mice express transcripts that lead to a truncated D2R protein lacking from the sixth transmembrane domain to the C-terminus. We share these findings to avoid future confusion and the community considers this mouse strain in D2R traffic and protein–protein interaction studies.
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Brodovskaya A, Shiono S, Kapur J. Activation of the basal ganglia and indirect pathway neurons during frontal lobe seizures. Brain 2021; 144:2074-2091. [PMID: 33730155 DOI: 10.1093/brain/awab119] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 12/12/2020] [Accepted: 01/04/2021] [Indexed: 12/27/2022] Open
Abstract
There are no detailed descriptions of neuronal circuit active during frontal lobe motor seizures. Using activity reporter mice, local field potential recordings, tissue clearing, viral tracing, and super-resolution microscopy, we found neuronal activation after focal motor to bilateral tonic-clonic seizures in the striatum, globus pallidus externus, subthalamic nucleus, substantia nigra pars reticulata and neurons of the indirect pathway. Seizures preferentially activated dopamine D2 receptor-expressing neurons over D1 in the striatum, which have different projections. Furthermore, the D2 receptor agonist infused into the striatum exerted an anticonvulsant effect. Seizures activate structures via short and long latency loops, and anatomical connections of the seizure focus determine the seizure circuit. These studies, for the first time, show activation of neurons in the striatum, globus pallidus, subthalamic nucleus, and substantia nigra during frontal lobe motor seizures on the cellular level, revealing a complex neuronal activation circuit subject to modulation by the basal ganglia.
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Affiliation(s)
- Anastasia Brodovskaya
- Neuroscience Graduate Program, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Shinnosuke Shiono
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Jaideep Kapur
- Department of Neurology, University of Virginia, Charlottesville, Virginia 22908, USA.,UVA Brain Institute, University of Virginia, Charlottesville, Virginia 22908, USA
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Yang JH, Sohn S, Kim S, Kim J, Oh JH, Ryu IS, Go BS, Choe ES. Repeated nicotine exposure increases the intracellular interaction between ERK-mGluR5 in the nucleus accumbens more in adult than adolescent rats. Addict Biol 2021; 26:e12913. [PMID: 32339332 DOI: 10.1111/adb.12913] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 03/20/2020] [Accepted: 04/09/2020] [Indexed: 11/27/2022]
Abstract
Intracellular interactions between protein kinases and metabotropic receptors in the striatum regulate behavioral changes in response to drug exposure. We investigated the difference in the degree of interaction between extracellular signal-regulated kinase (ERK) and metabotropic glutamate receptor subtype 5 (mGluR5) in the nucleus accumbens (NAc) after repeated exposure to nicotine in adult and adolescent rats. The results showed that repeated exposure to nicotine (0.5 mg/kg/day, s.c.) for seven consecutive days increased ERK phosphorylation more in adults than in adolescents. Furthermore, membrane expression of mGluR5 in gamma-aminobutyric acid (GABA) medium spiny neurons was higher in adults than adolescents as a result of repeated exposure to nicotine. Blockade of mGluR5 with MPEP (0.5 nmol/side) decreased the repeated nicotine-induced increase in ERK phosphorylation. Either blockade of mGluR5 or inhibition of ERK with SL327 (150 nmol/side) decreased the repeated nicotine-induced increase in the level of inositol-1,4,5-triphosphate (IP3 ), a key transducer associated with mGluR5-coupled signaling cascades. Similarly, interference of binding between activated ERK and mGluR5 by the blocking peptide, Tat-mGluR5-i (2 nmol/side), decreased the repeated nicotine-induced increases in IP3 and locomotor activity in adults. These findings suggest that the intracellular interaction between ERK and mGluR5 in the NAc is stronger in adult than in adolescent rats, which enhances the understanding of age-associated behavioral changes that occur after repeated exposure to nicotine.
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Affiliation(s)
- Ju Hwan Yang
- Department of Biological Sciences Pusan National University Busan South Korea
| | - Sumin Sohn
- Department of Biological Sciences Pusan National University Busan South Korea
| | - Sunghyun Kim
- Department of Biological Sciences Pusan National University Busan South Korea
| | - Jieun Kim
- Department of Biological Sciences Pusan National University Busan South Korea
| | - Jeong Hwan Oh
- Department of Biological Sciences Pusan National University Busan South Korea
- Institute of Fisheries Sciences Pukyong National University Busan South Korea
| | - In Soo Ryu
- Department of Biological Sciences Pusan National University Busan South Korea
- Korea Institute of Toxicology Daejeon South Korea
| | - Bok Soon Go
- Department of Biological Sciences Pusan National University Busan South Korea
| | - Eun Sang Choe
- Department of Biological Sciences Pusan National University Busan South Korea
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7
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Globus pallidus, but not entopeduncular nucleus, 6-OHDA-induced lesion attenuates L-Dopa-induced dyskinesia in the rat model of Parkinson's disease. Pharmacol Biochem Behav 2020; 197:173013. [DOI: 10.1016/j.pbb.2020.173013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 12/27/2022]
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8
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Okamoto S, Sohn J, Tanaka T, Takahashi M, Ishida Y, Yamauchi K, Koike M, Fujiyama F, Hioki H. Overlapping Projections of Neighboring Direct and Indirect Pathway Neostriatal Neurons to Globus Pallidus External Segment. iScience 2020; 23:101409. [PMID: 32877648 PMCID: PMC7520896 DOI: 10.1016/j.isci.2020.101409] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 06/15/2020] [Accepted: 07/22/2020] [Indexed: 02/06/2023] Open
Abstract
Indirect pathway medium-sized spiny neurons (iMSNs) in the neostriatum are well known to project to the external segment of the globus pallidus (GPe). Although direct MSNs (dMSNs) also send axon collaterals to the GPe, it remains unclear how dMSNs and iMSNs converge within the GPe. Here, we selectively labeled neighboring dMSNs and iMSNs with green and red fluorescent proteins using an adeno-associated virus vector and examined axonal projections of dMSNs and iMSNs to the GPe in mice. Both dMSNs and iMSNs formed two axonal arborizations displaying topographical projections in the dorsoventral and mediolateral planes. iMSNs displayed a wider and denser axon distribution, which included that of dMSNs. Density peaks of dMSN and iMSN axons almost overlapped, revealing convergence of dMSN axons in the center of iMSN projection fields. These overlapping projections suggest that dMSNs and iMSNs may work cooperatively via interactions within the GPe.
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Affiliation(s)
- Shinichiro Okamoto
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
- Advanced Research Institute for Health Sciences, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Jaerin Sohn
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Higashiyama Myodaiji, Okazaki, Aichi 444-8787, Japan
| | - Takuma Tanaka
- Graduate School of Data Science, Shiga University, 1-1-1 Banba, Hikone, Shiga 522-8522, Japan
| | - Megumu Takahashi
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
- Department of Neuroscience, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yoko Ishida
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Kenta Yamauchi
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
- Advanced Research Institute for Health Sciences, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Masato Koike
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
- Advanced Research Institute for Health Sciences, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Fumino Fujiyama
- Laboratory of Neural Circuitry, Graduate School of Brain Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto 610-0394, Japan
| | - Hiroyuki Hioki
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan
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9
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Kokane SS, Perrotti LI. Sex Differences and the Role of Estradiol in Mesolimbic Reward Circuits and Vulnerability to Cocaine and Opiate Addiction. Front Behav Neurosci 2020; 14:74. [PMID: 32508605 PMCID: PMC7251038 DOI: 10.3389/fnbeh.2020.00074] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 04/22/2020] [Indexed: 12/15/2022] Open
Abstract
Although both men and women become addicted to drugs of abuse, women transition to addiction faster, experience greater difficulties remaining abstinent, and relapse more often than men. In both humans and rodents, hormonal cycles are associated with females' faster progression to addiction. Higher concentrations and fluctuating levels of ovarian hormones in females modulate the mesolimbic reward system and influence reward-directed behavior. For example, in female rodents, estradiol (E2) influences dopamine activity within the mesolimbic reward system such that drug-directed behaviors that are normally rewarding and reinforcing become enhanced when circulating levels of E2 are high. Therefore, neuroendocrine interactions, in part, explain sex differences in behaviors motivated by drug reward. Here, we review sex differences in the physiology and function of the mesolimbic reward system in order to explore the notion that sex differences in response to drugs of abuse, specifically cocaine and opiates, are the result of molecular neuroadaptations that differentially develop depending upon the hormonal state of the animal. We also reconsider the notion that ovarian hormones, specifically estrogen/estradiol, sensitize target neurons thereby increasing responsivity when under the influence of either cocaine or opiates or in response to exposure to drug-associated cues. These adaptations may ultimately serve to guide the motivational behaviors that underlie the factors that cause women to be more vulnerable to cocaine and opiate addiction than men.
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Affiliation(s)
- Saurabh S Kokane
- Department of Psychology, University of Texas at Arlington, Arlington, TX, United States
| | - Linda I Perrotti
- Department of Psychology, University of Texas at Arlington, Arlington, TX, United States
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10
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McGregor MM, Nelson AB. Circuit Mechanisms of Parkinson's Disease. Neuron 2019; 101:1042-1056. [PMID: 30897356 DOI: 10.1016/j.neuron.2019.03.004] [Citation(s) in RCA: 259] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 02/11/2019] [Accepted: 03/01/2019] [Indexed: 12/27/2022]
Abstract
Parkinson's disease (PD) is a complex, multi-system neurodegenerative disorder. The second most common neurodegenerative disorder after Alzheimer's disease, it affects approximately 1% of adults over age 60. Diagnosis follows the development of one or more of the core motor features of the disease, including tremor, slowing of movement (bradykinesia), and rigidity. However, there are numerous other motor and nonmotor disease manifestations. Many PD symptoms result directly from neurodegeneration; others are driven by aberrant activity patterns in surviving neurons. This latter phenomenon, PD circuit dysfunction, is an area of intense study, as it likely underlies our ability to treat many disease symptoms in the face of (currently) irreversible neurodegeneration. This Review will discuss key clinical features of PD and their basis in neural circuit dysfunction. We will first review important disease symptoms and some of the responsible neuropathology. We will then describe the basal ganglia-thalamocortical circuit, the major locus of PD-related circuit dysfunction, and some of the models that have influenced its study. We will review PD-related changes in network activity, subdividing findings into those that touch on the rate, rhythm, or synchronization of neurons. Finally, we suggest some critical remaining questions for the field and areas for new developments.
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Affiliation(s)
- Matthew M McGregor
- Neuroscience Graduate Program, UCSF, San Francisco, CA 94158, USA; Department of Neurology, UCSF, San Francisco, CA 94158, USA
| | - Alexandra B Nelson
- Neuroscience Graduate Program, UCSF, San Francisco, CA 94158, USA; Department of Neurology, UCSF, San Francisco, CA 94158, USA; Weill Institute for Neurosciences, UCSF, San Francisco, CA 94158, USA; Kavli Institute for Fundamental Neuroscience, UCSF, San Francisco, CA 94158, USA.
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11
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Modulation and functions of dopamine receptor heteromers in drugs of abuse-induced adaptations. Neuropharmacology 2019; 152:42-50. [DOI: 10.1016/j.neuropharm.2018.12.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 11/27/2018] [Accepted: 12/03/2018] [Indexed: 12/18/2022]
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12
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Hasbi A, Perreault ML, Shen MYF, Fan T, Nguyen T, Alijaniaram M, Banasikowski TJ, Grace AA, O'Dowd BF, Fletcher PJ, George SR. Activation of Dopamine D1-D2 Receptor Complex Attenuates Cocaine Reward and Reinstatement of Cocaine-Seeking through Inhibition of DARPP-32, ERK, and ΔFosB. Front Pharmacol 2018; 8:924. [PMID: 29354053 PMCID: PMC5758537 DOI: 10.3389/fphar.2017.00924] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 12/05/2017] [Indexed: 12/12/2022] Open
Abstract
A significant subpopulation of neurons in rat nucleus accumbens (NAc) coexpress dopamine D1 and D2 receptors, which can form a D1-D2 receptor complex, but their relevance in addiction is not known. The existence of the D1-D2 heteromer in the striatum of rat and monkey was established using in situ PLA, in situ FRET and co-immunoprecipitation. In rat, D1-D2 receptor heteromer activation led to place aversion and abolished cocaine CPP and locomotor sensitization, cocaine intravenous self-administration and reinstatement of cocaine seeking, as well as inhibited sucrose preference and abolished the motivation to seek palatable food. Selective disruption of this heteromer by a specific interfering peptide induced reward-like effects and enhanced the above cocaine-induced effects, including at a subthreshold dose of cocaine. The D1-D2 heteromer activated Cdk5/Thr75-DARPP-32 and attenuated cocaine-induced pERK and ΔFosB accumulation, together with inhibition of cocaine-enhanced local field potentials in NAc, blocking thus the signaling pathway activated by cocaine: D1R/cAMP/PKA/Thr34-DARPP-32/pERK with ΔFosB accumulation. In conclusion, our results show that the D1-D2 heteromer exerted tonic inhibitory control of basal natural and cocaine reward, and therefore initiates a fundamental physiologic function that limits the liability to develop cocaine addiction.
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Affiliation(s)
- Ahmed Hasbi
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada
| | | | - Maurice Y F Shen
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada
| | - Theresa Fan
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada
| | - Tuan Nguyen
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada
| | | | - Tomek J Banasikowski
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Anthony A Grace
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Brian F O'Dowd
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada
| | - Paul J Fletcher
- Centre for Addiction and Mental Health, Toronto, ON, Canada.,Departments of Psychology and Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Susan R George
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada.,Department of Medicine, University of Toronto, Toronto, ON, Canada
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13
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Huang CCY, Ma T, Roltsch Hellard EA, Wang X, Selvamani A, Lu J, Sohrabji F, Wang J. Stroke triggers nigrostriatal plasticity and increases alcohol consumption in rats. Sci Rep 2017; 7:2501. [PMID: 28566754 PMCID: PMC5451385 DOI: 10.1038/s41598-017-02714-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 04/18/2017] [Indexed: 12/12/2022] Open
Abstract
Excessive alcohol consumption is a known risk factor for stroke, but the effect of stroke on alcohol intake is unknown. The dorsomedial striatum (DMS) and midbrain areas of the nigrostriatal circuit are critically associated to stroke and alcohol addiction. Here we sought to explore the influence of stroke on alcohol consumption and to uncover the underlying nigrostriatal mechanism. Rats were trained to consume alcohol using a two-bottle choice or operant self-administration procedure. Retrograde beads were infused into the DMS or midbrain to label specific neuronal types, and ischemic stroke was induced in the dorsolateral striatum (DLS). Slice electrophysiology was employed to measure excitability and synaptic transmission in DMS and midbrain neurons. We found that ischemic stroke-induced DLS infarction produced significant increases in alcohol preference, operant self-administration, and relapse. These increases were accompanied by enhanced excitability of DMS and midbrain neurons. In addition, glutamatergic inputs onto DMS D1-neurons was potentiated, whereas GABAergic inputs onto DMS-projecting midbrain dopaminergic neurons was suppressed. Importantly, systemic inhibition of dopamine D1 receptors attenuated the stroke-induced increase in operant alcohol self-administration. Our results suggest that the stroke-induced DLS infarction evoked abnormal plasticity in nigrostriatal dopaminergic neurons and DMS D1-neurons, contributing to increased post-stroke alcohol-seeking and relapse.
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Affiliation(s)
- Cathy C Y Huang
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA
| | - Tengfei Ma
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA
| | - Emily A Roltsch Hellard
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA
| | | | - Amutha Selvamani
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA
| | - Jiayi Lu
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA
| | - Farida Sohrabji
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA
| | - Jun Wang
- Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, 77807, USA.
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14
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Gagnon D, Petryszyn S, Sanchez MG, Bories C, Beaulieu JM, De Koninck Y, Parent A, Parent M. Striatal Neurons Expressing D 1 and D 2 Receptors are Morphologically Distinct and Differently Affected by Dopamine Denervation in Mice. Sci Rep 2017; 7:41432. [PMID: 28128287 PMCID: PMC5269744 DOI: 10.1038/srep41432] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 12/19/2016] [Indexed: 12/11/2022] Open
Abstract
The loss of nigrostriatal dopamine neurons in Parkinson’s disease induces a reduction in the number of dendritic spines on medium spiny neurons (MSNs) of the striatum expressing D1 or D2 dopamine receptor. Consequences on MSNs expressing both receptors (D1/D2 MSNs) are currently unknown. We looked for changes induced by dopamine denervation in the density, regional distribution and morphological features of D1/D2 MSNs, by comparing 6-OHDA-lesioned double BAC transgenic mice (Drd1a-tdTomato/Drd2-EGFP) to sham-lesioned animals. D1/D2 MSNs are uniformly distributed throughout the dorsal striatum (1.9% of MSNs). In contrast, they are heterogeneously distributed and more numerous in the ventral striatum (14.6% in the shell and 7.3% in the core). Compared to D1 and D2 MSNs, D1/D2 MSNs are endowed with a smaller cell body and a less profusely arborized dendritic tree with less dendritic spines. The dendritic spine density of D1/D2 MSNs, but also of D1 and D2 MSNs, is significantly reduced in 6-OHDA-lesioned mice. In contrast to D1 and D2 MSNs, the extent of dendritic arborization of D1/D2 MSNs appears unaltered in 6-OHDA-lesioned mice. Our data indicate that D1/D2 MSNs in the mouse striatum form a distinct neuronal population that is affected differently by dopamine deafferentation that characterizes Parkinson’s disease.
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Affiliation(s)
- D Gagnon
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
| | - S Petryszyn
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
| | - M G Sanchez
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
| | - C Bories
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
| | - J M Beaulieu
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
| | - Y De Koninck
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
| | - A Parent
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
| | - M Parent
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Department of Psychiatry and Neuroscience, Faculty of medicine, Université Laval, Quebec City, QC, Canada
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15
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Bernal-Casas D, Lee HJ, Weitz AJ, Lee JH. Studying Brain Circuit Function with Dynamic Causal Modeling for Optogenetic fMRI. Neuron 2017; 93:522-532.e5. [PMID: 28132829 DOI: 10.1016/j.neuron.2016.12.035] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 10/30/2016] [Accepted: 12/20/2016] [Indexed: 12/12/2022]
Abstract
Defining the large-scale behavior of brain circuits with cell type specificity is a major goal of neuroscience. However, neuronal circuit diagrams typically draw upon anatomical and electrophysiological measurements acquired in isolation. Consequently, a dynamic and cell-type-specific connectivity map has never been constructed from simultaneous measurements across the brain. Here, we introduce dynamic causal modeling (DCM) for optogenetic fMRI experiments-which uniquely allow cell-type-specific, brain-wide functional measurements-to parameterize the causal relationships among regions of a distributed brain network with cell type specificity. Strikingly, when applied to the brain-wide basal ganglia-thalamocortical network, DCM accurately reproduced the empirically observed time series, and the strongest connections were key connections of optogenetically stimulated pathways. We predict that quantitative and cell-type-specific descriptions of dynamic connectivity, as illustrated here, will empower novel systems-level understanding of neuronal circuit dynamics and facilitate the design of more effective neuromodulation therapies.
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Affiliation(s)
- David Bernal-Casas
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Hyun Joo Lee
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Andrew J Weitz
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Jin Hyung Lee
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA; Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA.
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16
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Błasiak E, Łukasiewicz S, Szafran-Pilch K, Dziedzicka-Wasylewska M. Genetic variants of dopamine D2 receptor impact heterodimerization with dopamine D1 receptor. Pharmacol Rep 2016; 69:235-241. [PMID: 28119185 DOI: 10.1016/j.pharep.2016.10.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 01/14/2023]
Abstract
BACKGROUND The human dopamine D2 receptor gene has three polymorphic variants that alter its amino acid sequence: alanine substitution by valine in position 96 (V96A), proline substitution by serine in position 310 (P310S) and serine substitution by cysteine in position 311 (S311C). Their functional role has never been the object of extensive studies, even though there is some evidence that their occurrence correlates with schizophrenia. METHODS The HEK293 cell line was transfected with dopamine D1 and D2 receptors (or genetic variants of the D2 receptor), coupled to fluorescent proteins which allowed us to measure the extent of dimerization of these receptors, using a highly advanced biophysical approach (FLIM-FRET). Additionally, Fluoro-4 AM was used to examine changes in the level of calcium release after ligand stimulation of cells expressing different combinations of dopamine receptors. RESULTS Using FLIM-FRET experiments we have shown that in HEK 293 expressing dopamine receptors, polymorphic mutations in the D2 receptor play a role in dimmer formation with the dopamine D1 receptor. The association level of dopamine receptors is affected by ligand administration, with variable effects depending on polymorphic variant of the D2 dopamine receptor. We have found that the level of heteromer formation is reflected by calcium ion release after ligand stimulation and have observed variations of this effect dependent on the polymorphic variant and the ligand. CONCLUSION The data presented in this paper support the hypothesis on the role of calcium signaling regulated by the D1-D2 heteromer which may be of relevance for schizophrenia etiology.
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Affiliation(s)
- Ewa Błasiak
- Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland.
| | - Sylwia Łukasiewicz
- Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland.
| | | | - Marta Dziedzicka-Wasylewska
- Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland; Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland.
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17
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Rico AJ, Dopeso-Reyes IG, Martínez-Pinilla E, Sucunza D, Pignataro D, Roda E, Marín-Ramos D, Labandeira-García JL, George SR, Franco R, Lanciego JL. Neurochemical evidence supporting dopamine D1-D2 receptor heteromers in the striatum of the long-tailed macaque: changes following dopaminergic manipulation. Brain Struct Funct 2016; 222:1767-1784. [PMID: 27612857 PMCID: PMC5406426 DOI: 10.1007/s00429-016-1306-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/06/2016] [Indexed: 11/13/2022]
Abstract
Although it has long been widely accepted that dopamine receptor types D1 and D2 form GPCR heteromers in the striatum, the presence of D1–D2 receptor heteromers has been recently challenged. In an attempt to properly characterize D1–D2 receptor heteromers, here we have used the in situ proximity ligation assay (PLA) in striatal sections comprising the caudate nucleus, the putamen and the core and shell territories of the nucleus accumbens. Experiments were carried out in control macaques as well as in MPTP-treated animals (with and without dyskinesia). Obtained data support the presence of D1–D2 receptor heteromers within all the striatal subdivisions, with the highest abundance in the accumbens shell. Dopamine depletion by MPTP resulted in an increase of D1–D2 density in caudate and putamen which was normalized by levodopa treatment. Two different sizes of heteromers were consistently found, thus suggesting that besides individual heteromers, D1–D2 receptor heteromers are sometimes organized in macromolecular complexes made of a number of D1–D2 heteromers. Furthermore, the PLA technique was combined with different neuronal markers to properly characterize the identities of striatal neurons expressing D1–D2 heteromers. We have found that striatal projection neurons giving rise to either the direct or the indirect basal ganglia pathways expressed D1–D2 heteromers. Interestingly, macromolecular complexes of D1–D2 heteromers were only found within cholinergic interneurons. In summary, here we provide overwhelming proof that D1 and D2 receptors form heteromeric complexes in the macaque striatum, thus representing a very appealing target for a number of brain diseases involving dopamine dysfunction.
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Affiliation(s)
- Alberto J Rico
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Iria G Dopeso-Reyes
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Eva Martínez-Pinilla
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Diego Sucunza
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Diego Pignataro
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Elvira Roda
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - David Marín-Ramos
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain
| | - José L Labandeira-García
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Department of Morphological Sciences, University of Santiago de Compostela, Santiago De Compostela, Spain
| | - Susan R George
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Departments of Medicine and Pharmacology, University of Toronto, Toronto, ON, Canada
| | - Rafael Franco
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.,Department of Biochemistry and Molecular Biology, University of Barcelona, Barcelona, Spain
| | - José L Lanciego
- Department of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pio XII Avenue 55, 31008, Pamplona, Spain. .,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
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18
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Perreault ML, Hasbi A, Shen MYF, Fan T, Navarro G, Fletcher PJ, Franco R, Lanciego JL, George SR. Disruption of a dopamine receptor complex amplifies the actions of cocaine. Eur Neuropsychopharmacol 2016; 26:1366-1377. [PMID: 27480020 DOI: 10.1016/j.euroneuro.2016.07.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 07/04/2016] [Accepted: 07/13/2016] [Indexed: 11/27/2022]
Abstract
Cocaine-induced increases in dopamine signaling in nucleus accumbens (NAc) play a significant role in cocaine seeking behavior. The majority of cocaine addiction research has focused on neuroanatomically segregated dopamine D1 and D2 receptor-expressing neurons, yet an involvement for those NAc neurons coexpressing D1 and D2 receptors in cocaine addiction has never been explored. In situ proximity ligation assay, confocal fluorescence resonance energy transfer and coimmunoprecipitation were used to show native D1 and D2 receptors formed a heteromeric complex in D1/D2 receptor-coexpressing neurons in rat and non-human primate NAc. D1-D2 heteromer expression was lower in NAc of adolescent rats compared to their adult counterparts. Functional disruption of the dopamine D1-D2 receptor heteromer, using a peptide targeting the site of interaction between the D1 and D2 receptor, induced conditioned place preference and increased NAc expression of ∆FosB. D1-D2 heteromer disruption also resulted in the promotion, exacerbation and acceleration of the locomotor activating and incentive motivational effects of cocaine in the self-administration paradigm. These findings support a model for tonic inhibition of basal and cocaine-induced reward processes by the D1-D2 heteromer thus highlighting its potential value as a novel target for drug discovery in cocaine addiction. Given that adolescents show increased drug abuse susceptibility, an involvement for reduced D1-D2 heteromer function in the heightened sensitivity to the rewarding effects of cocaine in adolescence is also implicated.
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Affiliation(s)
- Melissa L Perreault
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Ahmed Hasbi
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Maurice Y F Shen
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Theresa Fan
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Gemma Navarro
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | - Paul J Fletcher
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Departments of Psychology and Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Rafael Franco
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona, Barcelona, Spain; CIBERNED, Centro de Investigación en Red. Enfermedades Neurodegenerativas, Instituto de Salud Carlos III, Madrid, Spain
| | - José L Lanciego
- CIBERNED, Centro de Investigación en Red. Enfermedades Neurodegenerativas, Instituto de Salud Carlos III, Madrid, Spain; Department of Neurosciences, Center for Applied Medical Research, University of Navarra, Pamplona, Spain
| | - Susan R George
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada; Department of Medicine, University of Toronto, Toronto, ON, Canada.
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19
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Abstract
Unidirectional connections from the cortex to the matrix of the corpus striatum initiate the cortico-basal ganglia (BG)-thalamocortical loop, thought to be important in momentary action selection and in longer-term fine tuning of behavioural repertoire; a discrete set of striatal compartments, striosomes, has the complementary role of registering or anticipating reward that shapes corticostriatal plasticity. Re-entrant signals traversing the cortico-BG loop impact predominantly frontal cortices, conveyed through topographically ordered output channels; by contrast, striatal input signals originate from a far broader span of cortex, and are far more divergent in their termination. The term 'disclosed loop' is introduced to describe this organisation: a closed circuit that is open to outside influence at the initial stage of cortical input. The closed circuit component of corticostriatal afferents is newly dubbed 'operative', as it is proposed to establish the bid for action selection on the part of an incipient cortical action plan; the broader set of converging corticostriatal afferents is described as contextual. A corollary of this proposal is that every unit of the striatal volume, including the long, C-shaped tail of the caudate nucleus, should receive a mandatory component of operative input, and hence include at least one area of BG-recipient cortex amongst the sources of its corticostriatal afferents. Individual operative afferents contact twin classes of GABAergic striatal projection neuron (SPN), distinguished by their neurochemical character, and onward circuitry. This is the basis of the classic direct and indirect pathway model of the cortico-BG loop. Each pathway utilises a serial chain of inhibition, with two such links, or three, providing positive and negative feedback, respectively. Operative co-activation of direct and indirect SPNs is, therefore, pictured to simultaneously promote action, and to restrain it. The balance of this rival activity is determined by the contextual inputs, which summarise the external and internal sensory environment, and the state of ongoing behavioural priorities. Notably, the distributed sources of contextual convergence upon a striatal locus mirror the transcortical network harnessed by the origin of the operative input to that locus, thereby capturing a similar set of contingencies relevant to determining action. The disclosed loop formulation of corticostriatal and subsequent BG loop circuitry, as advanced here, refines the operating rationale of the classic model and allows the integration of more recent anatomical and physiological data, some of which can appear at variance with the classic model. Equally, it provides a lucid functional context for continuing cellular studies of SPN biophysics and mechanisms of synaptic plasticity.
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20
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Lee HJ, Weitz AJ, Bernal-Casas D, Duffy BA, Choy M, Kravitz AV, Kreitzer AC, Lee JH. Activation of Direct and Indirect Pathway Medium Spiny Neurons Drives Distinct Brain-wide Responses. Neuron 2016; 91:412-24. [PMID: 27373834 DOI: 10.1016/j.neuron.2016.06.010] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 04/06/2016] [Accepted: 05/27/2016] [Indexed: 12/28/2022]
Abstract
A central theory of basal ganglia function is that striatal neurons expressing the D1 and D2 dopamine receptors exert opposing brain-wide influences. However, the causal influence of each population has never been measured at the whole-brain scale. Here, we selectively stimulated D1 or D2 receptor-expressing neurons while visualizing whole-brain activity with fMRI. Excitation of either inhibitory population evoked robust positive BOLD signals within striatum, while downstream regions exhibited significantly different and generally opposing responses consistent with-though not easily predicted from-contemporary models of basal ganglia function. Importantly, positive and negative signals within the striatum, thalamus, GPi, and STN were all associated with increases and decreases in single-unit activity, respectively. These findings provide direct evidence for the opposing influence of D1 and D2 receptor-expressing striatal neurons on brain-wide circuitry and extend the interpretability of fMRI studies by defining cell-type-specific contributions to the BOLD signal.
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Affiliation(s)
- Hyun Joo Lee
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Andrew J Weitz
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - David Bernal-Casas
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Ben A Duffy
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - ManKin Choy
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA
| | - Alexxai V Kravitz
- National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA; Gladstone Institute of Neurological Disease, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Anatol C Kreitzer
- Gladstone Institute of Neurological Disease, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Jin Hyung Lee
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, Stanford, CA 94305, USA; Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA; Department of Electrical Engineering, Stanford University, Stanford, CA 94305, USA.
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21
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Bunner KD, Rebec GV. Corticostriatal Dysfunction in Huntington's Disease: The Basics. Front Hum Neurosci 2016; 10:317. [PMID: 27445757 PMCID: PMC4924423 DOI: 10.3389/fnhum.2016.00317] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 06/13/2016] [Indexed: 11/23/2022] Open
Abstract
The main input to the basal ganglia, the corticostriatal pathway, shows some of the earliest signs of neuropathology in Huntington’s disease (HD), an inherited neurodegenerative condition that typically strikes in mid-life with progressively deteriorating cognitive, emotional, and motor symptoms. Although an effective treatment remains elusive, research on transgenic animal models has implicated dysregulation of glutamate (Glu), the excitatory amino acid released by corticostriatal neurons, in HD onset. Abnormalities in the control of Glu transmission at the level of postsynaptic receptors and Glu transport proteins play a critical role in the loss of information flow through downstream circuits that set the stage for the HD behavioral phenotype. Parallel but less-well characterized changes in dopamine (DA), a key modulator of Glu activation, ensure further deficits in neuronal communication throughout the basal ganglia. Continued analysis of corticostriatal Glu transmission and its modulation by DA, including analysis at the neurobehavioral level in transgenic models, is likely to be an effective strategy in the pursuit of HD therapeutics.
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Affiliation(s)
- Kendra D Bunner
- Department of Psychological and Brain Sciences, Program in Neuroscience, Indiana University Bloomington, IN, USA
| | - George V Rebec
- Department of Psychological and Brain Sciences, Program in Neuroscience, Indiana University Bloomington, IN, USA
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22
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Reappraising striatal D1- and D2-neurons in reward and aversion. Neurosci Biobehav Rev 2016; 68:370-386. [PMID: 27235078 DOI: 10.1016/j.neubiorev.2016.05.021] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 05/16/2016] [Accepted: 05/22/2016] [Indexed: 12/31/2022]
Abstract
The striatum has been involved in complex behaviors such as motor control, learning, decision-making, reward and aversion. The striatum is mainly composed of medium spiny neurons (MSNs), typically divided into those expressing dopamine receptor D1, forming the so-called direct pathway, and those expressing D2 receptor (indirect pathway). For decades it has been proposed that these two populations exhibit opposing control over motor output, and recently, the same dichotomy has been proposed for valenced behaviors. Whereas D1-MSNs mediate reinforcement and reward, D2-MSNs have been associated with punishment and aversion. In this review we will discuss pharmacological, genetic and optogenetic studies that indicate that there is still controversy to what concerns the role of striatal D1- and D2-MSNs in this type of behaviors, highlighting the need to reconsider the early view that they mediate solely opposing aspects of valenced behaviour.
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23
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Mu S, Han L, Zhou G, Mo C, Duan J, He Z, Wang Z, Ren L, Zhang J. Protein regulation of induced pluripotent stem cells by transplanting in a Huntington's animal model. Neuropathol Appl Neurobiol 2016; 42:521-34. [PMID: 26859760 DOI: 10.1111/nan.12315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 01/25/2016] [Accepted: 02/09/2016] [Indexed: 11/26/2022]
Affiliation(s)
- S. Mu
- Psychology & Social College of Shenzhen University; Shenzhen China
| | - L. Han
- School of Medicine; Shenzhen University; Shenzhen China
| | - G. Zhou
- School of Medicine; Shenzhen University; Shenzhen China
| | - C. Mo
- School of Medicine; Shenzhen University; Shenzhen China
| | - J. Duan
- School of Medicine; Shenzhen University; Shenzhen China
| | - Z. He
- School of Medicine; Shenzhen University; Shenzhen China
| | - Z. Wang
- Department of Neurology; Shenzhen Shekou People's Hospital; Shenzhen China
| | - L. Ren
- Department of Neurology; Shenzhen Second People's Hospital (First Affiliated Hospital of Shenzhen University); Shenzhen China
| | - J. Zhang
- School of Medicine; Shenzhen University; Shenzhen China
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24
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mGluR4-containing corticostriatal terminals: synaptic interactions with direct and indirect pathway neurons in mice. Brain Struct Funct 2016; 221:4589-4599. [PMID: 26832920 DOI: 10.1007/s00429-016-1187-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 01/07/2016] [Indexed: 10/22/2022]
Abstract
Glutamatergic afferents from the cerebral cortex are the main excitatory drive of striatal projection neurons. The metabotropic glutamate receptor 4 (mGluR4) presynaptically modulates transmission at corticostriatal synapses, and is considered as a potent drug target for Parkinson's disease and other brain disorders. To better characterize the anatomical substrate that underlies the functional effects of mGluR4 in the striatum, we undertook electron microscopic localization studies of mGluR4 expression in the mouse striatum. Our data demonstrate that more than 80 % mGluR4-immunoreactive structures are accounted for by unmyelinated axons and axon terminals, and that almost 50 % putative glutamatergic terminals (i.e. forming asymmetric synapses) express mGluR4 in the mouse striatum. Using vGluT1 as a presynaptic marker of glutamatergic corticostriatal boutons, our findings indicate: (1) all striatal mGluR4-positive terminals co-express vGluT1 immunoreactivity, (2) 44.3 % total striatal glutamatergic terminals co-express vGluT1 and mGluR4, and (3) mGluR4 is expressed in 73.4 % of total striatal vGluT1-positive terminals. To determine if mGluR4 terminals target preferentially direct vs. indirect pathway neurons, mGluR4 immunostaining was combined with D1 receptor immunoreactivity. These data showed that around 30 % mGluR4-immunoreactive glutamatergic terminals target D1 receptor-positive spines (i.e. direct pathway neurons), while almost 70 % formed synapses with D1 receptor-negative spines (i.e. putative indirect pathway neurons). Thus, these immuno-electron microscopic studies suggest that pre-synaptic mGluR4 in striatal glutamatergic terminals is expressed almost exclusively in cortical boutons to subserve regulatory influences upon a large contingent of corticostriatal terminals that preferentially target putative "indirect" pathway striatal projection neurons in mice. These observations provide a rationale for the use of mGluR4 allosteric potentiator as a potential therapy in Parkinson's disease.
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25
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Farshi P, Fyk-Kolodziej B, Krolewski DM, Walker PD, Ichinose T. Dopamine D1 receptor expression is bipolar cell type-specific in the mouse retina. J Comp Neurol 2015; 524:2059-79. [PMID: 26587737 DOI: 10.1002/cne.23932] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 01/25/2023]
Abstract
In the retina, dopamine is a key molecule for daytime vision. Dopamine is released by retinal dopaminergic amacrine cells and transmits signaling either by conventional synaptic or by volume transmission. By means of volume transmission, dopamine modulates all layers of retinal neurons; however, it is not well understood how dopamine modulates visual signaling pathways in bipolar cells. Here we analyzed Drd1a-tdTomato BAC transgenic mice and found that the dopamine D1 receptor (D1R) is expressed in retinal bipolar cells in a type-dependent manner. Strong tdTomato fluorescence was detected in the inner nuclear layer and localized to type 1, 3b, and 4 OFF bipolar cells and type 5-2, XBC, 6, and 7 ON bipolar cells. In contrast, type 2, 3a, 5-1, 9, and rod bipolar cells did not express Drd1a-tdTomato. Other interneurons were also found to express tdTomato including horizontal cells and a subset (25%) of AII amacrine cells. Diverse visual processing pathways, such as color or motion-coded pathways, are thought to be initiated in retinal bipolar cells. Our results indicate that dopamine sculpts bipolar cell performance in a type-dependent manner to facilitate daytime vision. J. Comp. Neurol. 524:2059-2079, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Pershang Farshi
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Bozena Fyk-Kolodziej
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - David M Krolewski
- Molecular and Behavioral Neuroscience Institute, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Paul D Walker
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Tomomi Ichinose
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, USA.,Department of Ophthalmology, Wayne State University School of Medicine, Detroit, Michigan, USA
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26
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Shen MYF, Perreault ML, Bambico FR, Jones-Tabah J, Cheung M, Fan T, Nobrega JN, George SR. Rapid anti-depressant and anxiolytic actions following dopamine D1-D2 receptor heteromer inactivation. Eur Neuropsychopharmacol 2015; 25:2437-48. [PMID: 26431907 DOI: 10.1016/j.euroneuro.2015.09.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 07/23/2015] [Accepted: 09/10/2015] [Indexed: 01/06/2023]
Abstract
A role for the mesolimbic dopaminergic system in the pathophysiology of depression has become increasingly evident. Specifically, brain-derived neurotrophic factor (BDNF) has been shown to be elevated in the nucleus accumbens of depressed patients and to positively contribute to depression-like behaviour in rodents. The dopamine D1-D2 receptor heteromer exhibits significant expression in NAc and has also been shown to enhance BDNF expression and signalling in this region. We therefore examined the effects of D1-D2 heteromer stimulation in rats by SKF 83959, or its inactivation by a selective heteromer-disrupting TAT-D1 peptide on depression- and anxiety-like behaviours in non-stressed animals and in animals exposed to chronic unpredictable stress. SKF 83959 treatment significantly enhanced the latency to immobility in the forced swim test, increased the latency to drink condensed milk and reduced total milk consumption in the novelty-induced hypophagia test, and additionally reduced the total time spent in the open arms in the elevated plus maze test. These pro-depressant and anxiogenic effects of SKF 83959 were consistently abolished or attenuated by TAT-D1 peptide pre-treatment, signifying the behaviours were mediated by the D1-D2 heteromer. More importantly, in animals exposed to chronic unpredictable stress (CUS), TAT-D1 peptide treatment alone induced significant and rapid anxiolytic and antidepressant-like effects in two tests for CUS-induced anhedonia-like reactivity and in the novelty-suppressed feeding test. Together these findings indicate a positive role for the D1-D2 heteromer in mediating depression- and anxiety-like behaviours and suggest its possible value as a novel therapeutic target.
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Affiliation(s)
- Maurice Y F Shen
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada
| | - Melissa L Perreault
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada
| | - Francis R Bambico
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada
| | - Jace Jones-Tabah
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada
| | - Marco Cheung
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada
| | - Theresa Fan
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada
| | - José N Nobrega
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada
| | - Susan R George
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada; Department of Medicine, University of Toronto, Toronto, Ontario, Canada.
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Frederick AL, Yano H, Trifilieff P, Vishwasrao HD, Biezonski D, Mészáros J, Sibley DR, Kellendonk C, Sonntag KC, Graham DL, Colbran RJ, Stanwood GD, Javitch JA, Javitch JA. Evidence against dopamine D1/D2 receptor heteromers. Mol Psychiatry 2015; 20:1373-85. [PMID: 25560761 PMCID: PMC4492915 DOI: 10.1038/mp.2014.166] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 10/24/2014] [Accepted: 10/27/2014] [Indexed: 02/07/2023]
Abstract
Hetero-oligomers of G-protein-coupled receptors have become the subject of intense investigation, because their purported potential to manifest signaling and pharmacological properties that differ from the component receptors makes them highly attractive for the development of more selective pharmacological treatments. In particular, dopamine D1 and D2 receptors have been proposed to form hetero-oligomers that couple to Gαq proteins, and SKF83959 has been proposed to act as a biased agonist that selectively engages these receptor complexes to activate Gαq and thus phospholipase C. D1/D2 heteromers have been proposed as relevant to the pathophysiology and treatment of depression and schizophrenia. We used in vitro bioluminescence resonance energy transfer, ex vivo analyses of receptor localization and proximity in brain slices, and behavioral assays in mice to characterize signaling from these putative dimers/oligomers. We were unable to detect Gαq or Gα11 protein coupling to homomers or heteromers of D1 or D2 receptors using a variety of biosensors. SKF83959-induced locomotor and grooming behaviors were eliminated in D1 receptor knockout (KO) mice, verifying a key role for D1-like receptor activation. In contrast, SKF83959-induced motor responses were intact in D2 receptor and Gαq KO mice, as well as in knock-in mice expressing a mutant Ala(286)-CaMKIIα that cannot autophosphorylate to become active. Moreover, we found that, in the shell of the nucleus accumbens, even in neurons in which D1 and D2 receptor promoters are both active, the receptor proteins are segregated and do not form complexes. These data are not compatible with SKF83959 signaling through Gαq or through a D1/D2 heteromer and challenge the existence of such a signaling complex in the adult animals that we used for our studies.
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Affiliation(s)
- Aliya L. Frederick
- Neuroscience Graduate Program, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Hideaki Yano
- Departments of Psychiatry and Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Pierre Trifilieff
- Nutrition and Integrative Neurobiology, INRA UMR 1286; University of Bordeaux, F-33076, Bordeaux, France,Center for Neuroscience. Columbia University, Kolb Research Building, New York, NY10032, USA
| | - Harshad D. Vishwasrao
- Center for Neuroscience. Columbia University, Kolb Research Building, New York, NY10032, USA
| | - Dominik Biezonski
- Departments of Psychiatry and Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - József Mészáros
- Departments of Psychiatry and Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - David R. Sibley
- Molecular Neuropharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Christoph Kellendonk
- Departments of Psychiatry and Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York, USA,Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, New York, USA
| | - Kai C. Sonntag
- Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, MA, USA
| | - Devon L. Graham
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Roger J. Colbran
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA,Vanderbilt Kennedy Center and Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Gregg D. Stanwood
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA,Vanderbilt Kennedy Center and Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Jonathan A. Javitch
- Departments of Psychiatry and Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York, USA,Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, New York, USA
| | - J A Javitch
- Departments of Psychiatry and Pharmacology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.,Division of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, USA
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Ikemoto S, Yang C, Tan A. Basal ganglia circuit loops, dopamine and motivation: A review and enquiry. Behav Brain Res 2015; 290:17-31. [PMID: 25907747 DOI: 10.1016/j.bbr.2015.04.018] [Citation(s) in RCA: 139] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 04/09/2015] [Accepted: 04/11/2015] [Indexed: 12/26/2022]
Abstract
Dopamine neurons located in the midbrain play a role in motivation that regulates approach behavior (approach motivation). In addition, activation and inactivation of dopamine neurons regulate mood and induce reward and aversion, respectively. Accumulating evidence suggests that such motivational role of dopamine neurons is not limited to those located in the ventral tegmental area, but also in the substantia nigra. The present paper reviews previous rodent work concerning dopamine's role in approach motivation and the connectivity of dopamine neurons, and proposes two working models: One concerns the relationship between extracellular dopamine concentration and approach motivation. High, moderate and low concentrations of extracellular dopamine induce euphoric, seeking and aversive states, respectively. The other concerns circuit loops involving the cerebral cortex, basal ganglia, thalamus, epithalamus, and midbrain through which dopaminergic activity alters approach motivation. These models should help to generate hypothesis-driven research and provide insights for understanding altered states associated with drugs of abuse and affective disorders.
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Affiliation(s)
- Satoshi Ikemoto
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA.
| | - Chen Yang
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
| | - Aaron Tan
- Behavioral Neuroscience Branch, National Institute on Drug Abuse, National Institutes of Health, 251 Bayview Blvd., Suite 200, Baltimore, MD 21224, USA
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29
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Deng Y, Lanciego J, Kerkerian-Le-Goff L, Coulon P, Salin P, Kachidian P, Lei W, Del Mar N, Reiner A. Differential organization of cortical inputs to striatal projection neurons of the matrix compartment in rats. Front Syst Neurosci 2015; 9:51. [PMID: 25926776 PMCID: PMC4396197 DOI: 10.3389/fnsys.2015.00051] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 03/12/2015] [Indexed: 11/13/2022] Open
Abstract
In prior studies, we described the differential organization of corticostriatal and thalamostriatal inputs to the spines of direct pathway (dSPNs) and indirect pathway striatal projection neurons (iSPNs) of the matrix compartment. In the present electron microscopic (EM) analysis, we have refined understanding of the relative amounts of cortical axospinous vs. axodendritic input to the two types of SPNs. Of note, we found that individual dSPNs receive about twice as many axospinous synaptic terminals from IT-type (intratelencephalically projecting) cortical neurons as they do from PT-type (pyramidal tract projecting) cortical neurons. We also found that PT-type axospinous synaptic terminals were about 1.5 times as common on individual iSPNs as IT-type axospinous synaptic terminals. Overall, a higher percentage of IT-type terminals contacted dSPN than iSPN spines, while a higher percentage of PT-type terminals contacted iSPN than dSPN spines. Notably, IT-type axospinous synaptic terminals were significantly larger on iSPN spines than on dSPN spines. By contrast to axospinous input, the axodendritic PT-type input to dSPNs was more substantial than that to iSPNs, and the axodendritic IT-type input appeared to be meager and comparable for both SPN types. The prominent axodendritic PT-type input to dSPNs may accentuate their PT-type responsiveness, and the large size of axospinous IT-type terminals on iSPNs may accentuate their IT-type responsiveness. Using transneuronal labeling with rabies virus to selectively label the cortical neurons with direct input to the dSPNs projecting to the substantia nigra pars reticulata, we found that the input predominantly arose from neurons in the upper layers of motor cortices, in which IT-type perikarya predominate. The differential cortical input to SPNs is likely to play key roles in motor control and motor learning.
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Affiliation(s)
- Yunping Deng
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center Memphis, TN, USA
| | - Jose Lanciego
- Neurosciences Division, Center for Applied Medical Research (CIMA), Centro de Investigación Biomédica en Red sobre Enfermedades Neurosdegenerativas (CIBERNED), and Instituto de Investigación Sanitaria de Navarra (IdiSNA), University of Navarra Medical College Pamplona, Spain
| | | | - Patrice Coulon
- Aix Marseille Université, CNRS, INT UMR 7289 Marseille, France
| | - Pascal Salin
- Aix-Marseille Université, CNRS, IBDM UMR 7288 Marseille, France
| | | | - Wanlong Lei
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center Memphis, TN, USA ; Department of Anatomy, Zhongshan Medical School of Sun Yat-Sen University Guangzhou, China
| | - Nobel Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center Memphis, TN, USA
| | - Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center Memphis, TN, USA
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30
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Biezonski DK, Trifilieff P, Meszaros J, Javitch JA, Kellendonk C. Evidence for limited D1 and D2 receptor coexpression and colocalization within the dorsal striatum of the neonatal mouse. J Comp Neurol 2015; 523:1175-89. [PMID: 25556545 DOI: 10.1002/cne.23730] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 12/12/2014] [Accepted: 12/15/2014] [Indexed: 01/09/2023]
Abstract
The striatum is the major input nucleus of the basal ganglia involved in reward processing, goal-directed behaviors, habit learning, and motor control. The striatum projects to the basal ganglia output nuclei via the "direct" and "indirect" pathways, which can be distinguished by their projection fields and their opposing effects on behavior. In adult animals, the functional opposition is modulated by the differential actions of D1 and D2 dopamine receptors (D1R, D2R), the expression of which is largely separated between these pathways. To determine whether a similar degree of separation exists earlier in development, we used dual-label immunohistochemistry to map dorsal-striatal D1R and D2R expression at the promoter level in postnatal day 0 (PD0) Drd1a-tdTomato/Drd2-GFP BAC transgenic mice, and at the receptor level by costaining for native D1R and D2R in wildtype (WT) PD0 animals. To assess for potential molecular interactions between D1R and D2R we also employed a recently developed proximity-ligation assay (PLA). Limited coexpression and colocalization of the D1R and D2R proteins was found in clusters of neurons endemic to the "patch" compartment as identified by costaining with tyrosine hydroxylase, but not outside these clusters. Moreover, in contrast to our recent findings where we failed to detect a D1R-D2R PLA signal in the adult striatum, in PD0 striatum we did identify a clear PLA signal for this pair of receptors. This colocalization at close proximity points to a possible role for D1R/D2R-mediated crosstalk in early striatal ontogeny.
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Affiliation(s)
- Dominik K Biezonski
- Department of Psychiatry, Division of Molecular Therapeutics, Columbia University, New York State Psychiatric Institute, New York, New York, 10032, USA
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31
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Perreault ML, Shen MYF, Fan T, George SR. Regulation of c-fos expression by the dopamine D1-D2 receptor heteromer. Neuroscience 2014; 285:194-203. [PMID: 25446350 DOI: 10.1016/j.neuroscience.2014.11.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 11/03/2014] [Accepted: 11/10/2014] [Indexed: 11/24/2022]
Abstract
The dopamine D1 and D2 receptors form the D1-D2 receptor heteromer in a subset of neurons and couple to the Gq protein to regulate intracellular calcium signaling. In the present study the effect of D1-D2 heteromer activation and disruption on neuronal activation in the rat brain was mapped. This was accomplished using the dopamine agonist SKF 83959 to activate the D1-D2 heteromer in combination with a TAT-D1 disrupting peptide we developed, and which has been shown to disrupt the D1/D2 receptor interaction and antagonize D1-D2 heteromer-induced cell signaling and behavior. Acute SKF 83959 administration to rats induced significant c-fos expression in the nucleus accumbens that was significantly inhibited by TAT-D1 pretreatment. No effects of SKF 83959 were seen in caudate putamen. D1-D2 heteromer disruption by TAT-D1 did not have any effects in any striatal subregions, but induced significant c-fos immunoreactivity in a number of cortical regions including the orbitofrontal cortex, prelimbic and infralimbic cortices and piriform cortex. The induction of c-fos by TAT-D1 was also evident in the anterior olfactory nucleus, as well as the lateral habenula and thalamic nuclei. These findings show for the first time that the D1-D2 heteromer can differentially regulate c-fos expression in a region-dependent manner either through its activation or through tonic inhibition of neuronal activity.
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Affiliation(s)
- M L Perreault
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - M Y F Shen
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - T Fan
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - S R George
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada; Department of Medicine, University of Toronto, Toronto, ON, Canada.
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Mu S, Lin E, Liu B, Ma Y, OuYang L, Li Y, Chen S, Zhang J, Lei W. Melatonin reduces projection neuronal injury induced by 3-nitropropionic acid in the rat striatum. NEURODEGENER DIS 2014; 14:139-50. [PMID: 25342207 DOI: 10.1159/000365891] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 07/10/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Melatonin has shown a protective effect against various oxidative damages in the nervous system. Our previous studies have also confirmed its effect on behavioral dysfunction of experimental rats and injury of striatal interneurons induced by 3-nitropropionic acid. The present study aimed to further determine the effect of melatonin on the injury of striatal projection neurons induced by 3-nitropropionic acid. METHODS Classic histology, immunohistochemistry, Western blotting and immunoelectron microscopy were applied in this study. RESULTS The results were as follows: (1) in the striatum, 3-nitropropionic acid induced a clear lesion area with a transition zone around it, in which both D1+ and D2+ fibers were decreased significantly. However, in the group with melatonin treatment, the striatal lesion area was smaller than in the 3-nitropropionic acid group and the loss of D1+ and D2+ fibers was less pronounced than in the 3-nitropropionic acid group. (2) Histochemical results showed that the dendritic spine density of striatal projection neurons was decreased more seriously after 3-nitropropionic acid treatment, whereas the loss of dendritic spines was less marked in the melatonin-treated group than in the 3- nitropropionic acid group. Immunoelectron microscopy showed that the density of D1+ and D2+ dendrites and spines was significantly decreased in the 3-nitropropionic acid group, and the loss of D1+ and D2+ spines as well as D2+ dendrites was significantly reversed by melatonin administration. (3) Western blotting showed that the expression level of projection neuron protein markers decreased more significantly in the 3-nitropropionic acid group than in the control group and increased significantly in the melatonin-treated group. CONCLUSIONS The present results suggest that 3-nitropropionic acid induces serious injury of striatal projection neurons and that melatonin effectively protects against this pathological damage.
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Affiliation(s)
- Shuhua Mu
- Department of Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
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Calabresi P, Picconi B, Tozzi A, Ghiglieri V, Di Filippo M. Direct and indirect pathways of basal ganglia: a critical reappraisal. Nat Neurosci 2014; 17:1022-30. [DOI: 10.1038/nn.3743] [Citation(s) in RCA: 474] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 05/21/2014] [Indexed: 12/12/2022]
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34
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Lee SM, Yang Y, Mailman RB. Dopamine D1 receptor signaling: does GαQ-phospholipase C actually play a role? J Pharmacol Exp Ther 2014; 351:9-17. [PMID: 25052835 DOI: 10.1124/jpet.114.214411] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Despite numerous studies showing therapeutic potential, no central dopamine D1 receptor ligand has ever been approved, because of potential limitations, such as hypotension, seizures, and tolerance. Functional selectivity has been widely recognized as providing a potential mechanism to develop novel therapeutics from existing targets, and a highly biased, functionally selective D1 ligand might overcome some of the past limitations. SKF-83959 [6-chloro-3-methyl-1-(m-tolyl)-2,3,4,5-tetrahydro-1H-benzo[d]azepine-7,8-diol] is reported to be a highly biased D1 ligand, having full agonism at D1-mediated activation of phospholipase C (PLC) signaling (via GαQ) and antagonism at D1-mediated adenylate cyclase signaling (via GαOLF/S). For this reason, numerous studies have used this compound to elucidate the physiologic role of D1-PLC signaling, including a novel molecular mechanism (GαQ-PLC activation via D1-D2 heterodimers). There is, however, contradictory literature that suggests that SKF-83959 is actually a partial agonist at both D1-mediated adenylate cyclase and β-arrestin recruitment. Moreover, the D1-mediated PLC stimulation has also been questioned. This Minireview examines 30 years of relevant literature and proposes that the data strongly favor alternate hypotheses: first, that SKF-83959 is a typical D1 partial agonist; and second, that the reported activation of PLC by SKF-83959 and related benzazepines likely is due to off-target effects, not actions at D1 receptors. If these hypotheses are supported by future studies, it would suggest that caution should be used regarding the role of PLC and downstream pathways in D1 signaling.
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Affiliation(s)
- Sang-Min Lee
- Departments of Pharmacology (S.-M.L., Y.Y., R.B.M.) and Neurology (Y.Y., R.B.M.), Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Yang Yang
- Departments of Pharmacology (S.-M.L., Y.Y., R.B.M.) and Neurology (Y.Y., R.B.M.), Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Richard B Mailman
- Departments of Pharmacology (S.-M.L., Y.Y., R.B.M.) and Neurology (Y.Y., R.B.M.), Pennsylvania State University College of Medicine, Hershey, Pennsylvania
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Nishijima H, Suzuki S, Kon T, Funamizu Y, Ueno T, Haga R, Suzuki C, Arai A, Kimura T, Suzuki C, Meguro R, Miki Y, Yamada J, Migita K, Ichinohe N, Ueno S, Baba M, Tomiyama M. Morphologic changes of dendritic spines of striatal neurons in the levodopa-induced dyskinesia model. Mov Disord 2014; 29:336-43. [PMID: 24573720 DOI: 10.1002/mds.25826] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 12/20/2013] [Accepted: 12/30/2013] [Indexed: 11/07/2022] Open
Abstract
Maladaptive plasticity at corticostriatal synapses plays an important role in the development of levodopa-induced dyskinesia. Recently, it has been shown that synaptic plasticity is closely linked to morphologic changes of dendritic spines. To evaluate morphologic changes of dendritic spines of two types of striatal medium spiny neurons, which project to the internal segment of globus pallidus or the external segment of globus pallidus, in the levodopa-induced dyskinesia model, we used 6-hydroxydopamine-lesioned rats chronically treated with levodopa. Dendritic spines were decreased and became enlarged in the direct pathway neurons of the model of levodopa-induced dyskinesia. The same levodopa treatment to normal rats, in which no dyskinesia was observed, also induced enlargement of dendritic spines, but not a decrease in density of spines in the direct pathway neurons. These results suggest that a loss and enlargement of dendritic spines in the direct pathway neurons plays important roles in the development of levodopa-induced dyskinesia.
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Affiliation(s)
- Haruo Nishijima
- Department of Neurology, Aomori Prefectural Central Hospital, Aomori City, Aomori, Japan; Department of Neurophysiology, Institute of Brain Science, Hirosaki University Graduate School of Medicine, Hirosaki City, Aomori, Japan
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Tai AX, Cassidy RM, Kromer LF. EphA7 expression identifies a unique neuronal compartment in the rat striatum. J Comp Neurol 2014; 521:2663-79. [PMID: 23348681 DOI: 10.1002/cne.23308] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 01/03/2013] [Accepted: 01/17/2013] [Indexed: 01/26/2023]
Abstract
Prior studies have identified two anatomically and neurochemically distinct cellular compartments within the mammalian striatum, termed striosomes and matrix, which express μ-opioid receptors (μOR) and EphA4, respectively. Here we identify and characterize an additional compartment in the rat striatum composed of neurons that express EphA7. In situ hybridization and immunohistochemical data indicate that neurons expressing EphA7 mRNA and protein are arranged in a banded "matrisome-like" pattern confined to the matrix in the dorsal striatum. Within the ventral striatum, EphA7-positive (+) neurons have a less organized mosaic pattern that partially overlaps areas expressing μOR. Immunolabeling data demonstrate that EphA7+ striatofugal axons form distinct fascicles leaving the striatum. Within the globus pallidus, EphA7+ axons terminate primarily within ventromedial areas of the nucleus and along its striatal border. EphA7+ axons avoid regions containing dopamine neurons within the substantia nigra and preferentially innervate areas near the rostral and caudal margins of the nucleus. Within both nuclei, EphA7+ axons have similar but more restricted terminal fields than the entire population of EphA4+ matrix axons, indicating that EphA7+ axons comprise a subpopulation of matrix axons. Ligand binding data demonstrate that ephrin-A5 selectively binds areas of the striatum, globus pallidus, and substantia nigra containing EphA7+ neurons and axons, but not areas expressing only EphA4. Our findings demonstrate that EphA7 expression identifies a novel "matrisome" compartment within the matrix that binds ephrin-A5 and possesses unique axonal projections. Our findings also suggest that EphA7 and ephrin-A5 may participate in the formation of this matrisome subcompartment and its striatofugal projections.
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Affiliation(s)
- Alexander X Tai
- Department of Neuroscience, Georgetown University Medical Center, Washington, DC 20007, USA
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Selective inhibition of phosphodiesterase 10A impairs appetitive and aversive conditioning and incentive salience attribution. Neuropharmacology 2013; 75:437-44. [DOI: 10.1016/j.neuropharm.2013.08.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 06/27/2013] [Accepted: 08/12/2013] [Indexed: 11/18/2022]
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Klanker M, Feenstra M, Denys D. Dopaminergic control of cognitive flexibility in humans and animals. Front Neurosci 2013; 7:201. [PMID: 24204329 PMCID: PMC3817373 DOI: 10.3389/fnins.2013.00201] [Citation(s) in RCA: 148] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 10/11/2013] [Indexed: 12/21/2022] Open
Abstract
Striatal dopamine (DA) is thought to code for learned associations between cues and reinforcers and to mediate approach behavior toward a reward. Less is known about the contribution of DA to cognitive flexibility—the ability to adapt behavior in response to changes in the environment. Altered reward processing and impairments in cognitive flexibility are observed in psychiatric disorders such as obsessive compulsive disorder (OCD). Patients with this disorder show a disruption of functioning in the frontostriatal circuit and alterations in DA signaling. In this review we summarize findings from animal and human studies that have investigated the involvement of striatal DA in cognitive flexibility. These findings may provide a better understanding of the role of dopaminergic dysfunction in cognitive inflexibility in psychiatric disorders, such as OCD.
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Affiliation(s)
- Marianne Klanker
- Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences Amsterdam, Netherlands ; Department of Psychiatry, Academic Medical Center, University of Amsterdam Amsterdam, Netherlands
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Lei W, Deng Y, Liu B, Mu S, Guley NM, Wong T, Reiner A. Confocal laser scanning microscopy and ultrastructural study of VGLUT2 thalamic input to striatal projection neurons in rats. J Comp Neurol 2013; 521:1354-77. [PMID: 23047588 DOI: 10.1002/cne.23235] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 08/31/2012] [Accepted: 10/02/2012] [Indexed: 01/17/2023]
Abstract
We examined thalamic input to striatum in rats using immunolabeling for the vesicular glutamate transporter (VGLUT2). Double immunofluorescence viewed with confocal laser scanning microscopy (CLSM) revealed that VGLUT2+ terminals are distinct from VGLUT1+ terminals. CLSM of Phaseolus vulgaris-leucoagglutinin (PHAL)-labeled cortical or thalamic terminals revealed that VGLUT2 is rare in corticostriatal terminals but nearly always present in thalamostriatal terminals. Electron microscopy revealed that VGLUT2+ terminals made up 39.4% of excitatory terminals in striatum (with VGLUT1+ corticostriatal terminals constituting the rest), and 66.8% of VGLUT2+ terminals synapsed on spines and the remainder on dendrites. VGLUT2+ axospinous terminals had a mean diameter of 0.624 μm, while VGLUT2+ axodendritic terminals a mean diameter of 0.698 μm. In tissue in which we simultaneously immunolabeled thalamostriatal terminals for VGLUT2 and striatal neurons for D1 (with about half of spines immunolabeled for D1), 54.6% of VGLUT2+ terminals targeted D1+ spines (i.e., direct pathway striatal neurons), and 37.3% of D1+ spines received VGLUT2+ synaptic contacts. By contrast, 45.4% of VGLUT2+ terminals targeted D1-negative spines (i.e., indirect pathway striatal neurons), and only 25.8% of D1-negative spines received VGLUT2+ synaptic contacts. Similarly, among VGLUT2+ axodendritic synaptic terminals, 59.1% contacted D1+ dendrites, and 40.9% contacted D1-negative dendrites. VGLUT2+ terminals on D1+ spines and dendrites tended to be slightly smaller than those on D1-negative spines and dendrites. Thus, thalamostriatal terminals contact both direct and indirect pathway striatal neurons, with a slight preference for direct. These results are consistent with physiological studies indicating slightly different effects of thalamic input on the two types of striatal projection neurons.
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Affiliation(s)
- Wanlong Lei
- Department of Anatomy, Zhongshan Medical School of Sun Yat-Sen University, Guangzhou, 510080, PR China.
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Loss of corticostriatal and thalamostriatal synaptic terminals precedes striatal projection neuron pathology in heterozygous Q140 Huntington's disease mice. Neurobiol Dis 2013; 60:89-107. [PMID: 23969239 DOI: 10.1016/j.nbd.2013.08.009] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 07/22/2013] [Accepted: 08/07/2013] [Indexed: 01/18/2023] Open
Abstract
Motor slowing, forebrain white matter loss, and striatal shrinkage have been reported in premanifest Huntington's disease (HD) prior to overt striatal neuron loss. We carried out detailed LM and EM studies in a genetically precise HD mimic, heterozygous Q140 HD knock-in mice, to examine the possibility that loss of corticostriatal and thalamostriatal terminals prior to striatal neuron loss underlies these premanifest HD abnormalities. In our studies, we used VGLUT1 and VGLUT2 immunolabeling to detect corticostriatal and thalamostriatal (respectively) terminals in dorsolateral (motor) striatum over the first year of life, prior to striatal projection neuron pathology. VGLUT1+ axospinous corticostriatal terminals represented about 55% of all excitatory terminals in striatum, and VGLUT2+ axospinous thalamostriatal terminals represented about 35%, with VGLUT1+ and VGLUT2+ axodendritic terminals accounting for the remainder. In Q140 mice, a significant 40% shortfall in VGLUT2+ axodendritic thalamostriatal terminals and a 20% shortfall in axospinous thalamostriatal terminals were already observed at 1 month of age, but VGLUT1+ terminals were normal in abundance. The 20% deficiency in VGLUT2+ thalamostriatal axospinous terminals persisted at 4 and 12 months in Q140 mice, and an additional 30% loss of VGLUT1+ corticostriatal terminals was observed at 12 months. The early and persistent deficiency in thalamostriatal axospinous terminals in Q140 mice may reflect a development defect, and the impoverishment of this excitatory drive to striatum may help explain early motor defects in Q140 mice and in premanifest HD. The loss of corticostriatal terminals at 1 year in Q140 mice is consistent with prior evidence from other mouse models of corticostriatal disconnection early during progression, and can explain both the measurable bradykinesia and striatal white matter loss in late premanifest HD.
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Huot P, Johnston TH, Koprich JB, Fox SH, Brotchie JM. The Pharmacology of l-DOPA-Induced Dyskinesia in Parkinson’s Disease. Pharmacol Rev 2013; 65:171-222. [DOI: 10.1124/pr.111.005678] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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Jonkman S, Kenny PJ. Molecular, cellular, and structural mechanisms of cocaine addiction: a key role for microRNAs. Neuropsychopharmacology 2013; 38:198-211. [PMID: 22968819 PMCID: PMC3521966 DOI: 10.1038/npp.2012.120] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The rewarding properties of cocaine play a key role in establishing and maintaining the drug-taking habit. However, as exposure to cocaine increases, drug use can transition from controlled to compulsive. Importantly, very little is known about the neurobiological mechanisms that control this switch in drug use that defines addiction. MicroRNAs (miRNAs) are small non-protein coding RNA transcripts that can regulate the expression of messenger RNAs that code for proteins. Because of their highly pleiotropic nature, each miRNA has the potential to regulate hundreds or even thousands of protein-coding RNA transcripts. This property of miRNAs has generated considerable interest in their potential involvement in complex psychiatric disorders such as addiction, as each miRNA could potentially influence the many different molecular and cellular adaptations that arise in response to drug use that are hypothesized to drive the emergence of addiction. Here, we review recent evidence supporting a key role for miRNAs in the ventral striatum in regulating the rewarding and reinforcing properties of cocaine in animals with limited exposure to the drug. Moreover, we discuss evidence suggesting that miRNAs in the dorsal striatum control the escalation of drug intake in rats with extended cocaine access. These findings highlight the central role for miRNAs in drug-induced neuroplasticity in brain reward systems that drive the emergence of compulsive-like drug use in animals, and suggest that a better understanding of how miRNAs control drug intake will provide new insights into the neurobiology of drug addiction.
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Affiliation(s)
- Sietse Jonkman
- Laboratory of Behavioral and Molecular Neuroscience, Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute–Florida, Jupiter, FL, USA
| | - Paul J Kenny
- Laboratory of Behavioral and Molecular Neuroscience, Departments of Molecular Therapeutics and Neuroscience, The Scripps Research Institute–Florida, Jupiter, FL, USA,Laboratory of Behavioral and Molecular Neuroscience, Department of Molecular Therapeutics, The Scripps Research Institute—Florida, 130 Scripps Way, Jupiter, FL 33458, USA, Tel: +1 561 228 2231, Fax: +1 561 799 8961, E-mail:
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Feng X, Xu Z, Butler SG, Leng I, Zhang T, Kritchevsky SB. Effects of aging and levodopa on the laryngeal adductor reflex in rats. Exp Gerontol 2012; 47:900-7. [PMID: 22824541 PMCID: PMC4819337 DOI: 10.1016/j.exger.2012.07.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Revised: 07/12/2012] [Accepted: 07/13/2012] [Indexed: 11/22/2022]
Abstract
Dopaminergic neurotransmission plays an essential role in sensorimotor function, and declines with age. Previously, we found the laryngeal adductor reflex (LAR) was increased in excitation by a dopamine receptor antagonist. If this airway-protective reflex is similarly affected by aging, it will interfere with volitional control in older adults. The current study tested whether the LAR was affected by aging, and whether such deficits were reversed by levodopa administration in aging rats. We recorded thyroarytenoid (TA) muscle activity at rest and during elicitation of LAR responses by stimulation of the internal branch of the superior laryngeal nerve (iSLN) in 6-, 18- and 30-month-old rats under alpha-chloralose anesthesia. Using paired stimuli at different inter-stimulus intervals (ISIs), LAR central conditioning, resting muscle activity, and reflex latency and amplitudes were quantified. Numbers of dopaminergic neurons in the substantia nigra pars compacta (SNpc) were measured using tyrosine hydroxylase staining. We found: (1) increased resting TA muscle activity and LAR amplitude occurred with fewer dopaminergic neurons in the SNpc in 18- and 30-month-old rats; (2) decreases in LAR latency and increases in amplitude correlated with reduced numbers of dopaminergic neurons in the SNpc; (3) test responses were greater at 1000ms ISI in 18-month-old rats compared with 6-month-old rats; and (4) levodopa administration further increased response latency but did not alter muscle activity, response amplitude, or central conditioning. In conclusion, increases in laryngeal muscle activity levels and reflex amplitudes accompanied age reductions in dopaminergic neurons but were not reversed with levodopa administration.
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Affiliation(s)
- Xin Feng
- Department of Otolaryngology, Wake Forest School of Medicine, Winston-Salem, NC 27157, United States.
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44
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Delis F, Mitsacos A, Giompres P. Lesion of the cerebellar paravermis increases dopamine D1 receptor levels in the contralateral striatum. J Chem Neuroanat 2012; 47:35-41. [PMID: 23116569 DOI: 10.1016/j.jchemneu.2012.10.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 10/21/2012] [Accepted: 10/21/2012] [Indexed: 12/22/2022]
Abstract
Anatomical and biochemical findings have long suggested that a projection from the cerebellum to the basal ganglia exists, and recent findings proposed that the cerebellum influences glutamatergic striatal activity. We have previously shown that a complete, genetic, lack of Purkinje cells induces an upregulation of dopamine D1 receptors (DRD1) in the output of the basal ganglia, the substantia nigra pars reticulata. In this study, we produced a focal unilateral lesion in the cerebellar paravermal cortex and we studied the levels and distribution of dopamine receptors and transporters, with the use of in vitro receptor autoradiography. The lesion produced a statistically significant increase in DRD1 specific binding in the contralateral medial striatum and a bilateral decrease in dopamine transporter (DAT) levels in the dorsolateral striatum. Our finding of a DRD1 increase after disruption of the cerebellar corticonuclear projection suggests that the cerebellar output modulates the basal ganglia DRD1-mediated pathway.
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Affiliation(s)
- Foteini Delis
- Laboratory of Human and Animal Physiology, Department of Biology, University of Patras, Rio, Greece
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Choi JY, Kim CH, Jeon TJ, Cho WG, Lee JS, Lee SJ, Choi TH, Kim BS, Yi CH, Seo Y, Yi DI, Han SJ, Lee M, Kim DG, Lee JD, An G, Ryu YH. Evaluation of dopamine transporters and D2 receptors in hemiparkinsonian rat brains in vivo using consecutive PET scans of [18F]FPCIT and [18F]fallypride. Appl Radiat Isot 2012; 70:2689-94. [PMID: 23041777 DOI: 10.1016/j.apradiso.2012.08.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 08/02/2012] [Accepted: 08/08/2012] [Indexed: 02/07/2023]
Abstract
The aim of this study was to investigate dopaminergic function in unilaterally lesioned 6-OHDA rats by dual PET radioligands: [(18)F]FPCIT (a dopamine transporter imaging radioligand) and [(18)F]fallypride (a dopamine D2 receptors imaging radioligand). As a result, the brain uptake of [(18)F]FPCIT was significantly reduced and that of [(18)F]fallypride was increased in the ipsilateral striatum (lesion side) of the 6-OHDA rats. These findings implicated that dopamine transporter is down-regulated and dopamine D2 receptor is up-regulated in this hemiparkinsonian rat model.
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Affiliation(s)
- Jae Yong Choi
- Department of Pharmacology, Brain Research Institute, Brain Korea 21 Project for Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea
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A2A adenosine receptor antagonism enhances synaptic and motor effects of cocaine via CB1 cannabinoid receptor activation. PLoS One 2012; 7:e38312. [PMID: 22715379 PMCID: PMC3371006 DOI: 10.1371/journal.pone.0038312] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 05/08/2012] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Cocaine increases the level of endogenous dopamine (DA) in the striatum by blocking the DA transporter. Endogenous DA modulates glutamatergic inputs to striatal neurons and this modulation influences motor activity. Since D2 DA and A2A-adenosine receptors (A2A-Rs) have antagonistic effects on striatal neurons, drugs targeting adenosine receptors such as caffeine-like compounds, could enhance psychomotor stimulant effects of cocaine. In this study, we analyzed the electrophysiological effects of cocaine and A2A-Rs antagonists in striatal slices and the motor effects produced by this pharmacological modulation in rodents. PRINCIPAL FINDINGS Concomitant administration of cocaine and A2A-Rs antagonists reduced glutamatergic synaptic transmission in striatal spiny neurons while these drugs failed to produce this effect when given in isolation. This inhibitory effect was dependent on the activation of D2-like receptors and the release of endocannabinoids since it was prevented by L-sulpiride and reduced by a CB1 receptor antagonist. Combined application of cocaine and A2A-R antagonists also reduced the firing frequency of striatal cholinergic interneurons suggesting that changes in cholinergic tone might contribute to this synaptic modulation. Finally, A2A-Rs antagonists, in the presence of a sub-threshold dose of cocaine, enhanced locomotion and, in line with the electrophysiological experiments, this enhanced activity required activation of D2-like and CB1 receptors. CONCLUSIONS The present study provides a possible synaptic mechanism explaining how caffeine-like compounds could enhance psychomotor stimulant effects of cocaine.
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Dopamine D1-D2 receptor heteromer in dual phenotype GABA/glutamate-coexpressing striatal medium spiny neurons: regulation of BDNF, GAD67 and VGLUT1/2. PLoS One 2012; 7:e33348. [PMID: 22428025 PMCID: PMC3299775 DOI: 10.1371/journal.pone.0033348] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 02/13/2012] [Indexed: 12/15/2022] Open
Abstract
In basal ganglia a significant subset of GABAergic medium spiny neurons (MSNs) coexpress D1 and D2 receptors (D1R and D2R) along with the neuropeptides dynorphin (DYN) and enkephalin (ENK). These coexpressing neurons have been recently shown to have a region-specific distribution throughout the mesolimbic and basal ganglia circuits. While the functional relevance of these MSNs remains relatively unexplored, they have been shown to exhibit the unique property of expressing the dopamine D1–D2 receptor heteromer, a novel receptor complex with distinct pharmacology and cell signaling properties. Here we showed that MSNs coexpressing the D1R and D2R also exhibited a dual GABA/glutamate phenotype. Activation of the D1R–D2R heteromer in these neurons resulted in the simultaneous, but differential regulation of proteins involved in GABA and glutamate production or vesicular uptake in the nucleus accumbens (NAc), ventral tegmental area (VTA), caudate putamen and substantia nigra (SN). Additionally, activation of the D1R–D2R heteromer in NAc shell, but not NAc core, differentially altered protein expression in VTA and SN, regions rich in dopamine cell bodies. The identification of a MSN with dual inhibitory and excitatory intrinsic functions provides new insights into the neuroanatomy of the basal ganglia and demonstrates a novel source of glutamate in this circuit. Furthermore, the demonstration of a dopamine receptor complex with the potential to differentially regulate the expression of proteins directly involved in GABAergic inhibitory or glutamatergic excitatory activation in VTA and SN may potentially provide new insights into the regulation of dopamine neuron activity. This could have broad implications in understanding how dysregulation of neurotransmission within basal ganglia contributes to dopamine neuronal dysfunction.
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48
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Dopamine-dependent long-term depression is expressed in striatal spiny neurons of both direct and indirect pathways: implications for Parkinson's disease. J Neurosci 2011; 31:12513-22. [PMID: 21880913 DOI: 10.1523/jneurosci.2236-11.2011] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Striatal medium spiny neurons (MSNs) are divided into two subpopulations exerting distinct effects on motor behavior. Transgenic mice carrying bacterial artificial chromosome (BAC) able to confer cell type-specific expression of enhanced green fluorescent protein (eGFP) for dopamine (DA) receptors have been developed to characterize differences between these subpopulations. Analysis of these mice, in contrast with original pioneering studies, showed that striatal long-term depression (LTD) was expressed in indirect but not in the direct pathway MSNs. To address this mismatch, we applied a new approach using combined BAC technology and receptor immunohistochemistry. We demonstrate that, in physiological conditions, DA-dependent LTD is expressed in both pathways showing that the lack of synaptic plasticity found in D(1) eGFP mice is associated to behavioral deficits. Our findings suggest caution in the use of this tool and indicate that the "striatal segregation" hypothesis might not explain all synaptic dysfunctions in Parkinson's disease.
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49
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Fee MS, Goldberg JH. A hypothesis for basal ganglia-dependent reinforcement learning in the songbird. Neuroscience 2011; 198:152-70. [PMID: 22015923 DOI: 10.1016/j.neuroscience.2011.09.069] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Revised: 09/30/2011] [Accepted: 09/30/2011] [Indexed: 01/08/2023]
Abstract
Most of our motor skills are not innately programmed, but are learned by a combination of motor exploration and performance evaluation, suggesting that they proceed through a reinforcement learning (RL) mechanism. Songbirds have emerged as a model system to study how a complex behavioral sequence can be learned through an RL-like strategy. Interestingly, like motor sequence learning in mammals, song learning in birds requires a basal ganglia (BG)-thalamocortical loop, suggesting common neural mechanisms. Here, we outline a specific working hypothesis for how BG-forebrain circuits could utilize an internally computed reinforcement signal to direct song learning. Our model includes a number of general concepts borrowed from the mammalian BG literature, including a dopaminergic reward prediction error and dopamine-mediated plasticity at corticostriatal synapses. We also invoke a number of conceptual advances arising from recent observations in the songbird. Specifically, there is evidence for a specialized cortical circuit that adds trial-to-trial variability to stereotyped cortical motor programs, and a role for the BG in "biasing" this variability to improve behavioral performance. This BG-dependent "premotor bias" may in turn guide plasticity in downstream cortical synapses to consolidate recently learned song changes. Given the similarity between mammalian and songbird BG-thalamocortical circuits, our model for the role of the BG in this process may have broader relevance to mammalian BG function.
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Affiliation(s)
- M S Fee
- McGovern Institute for Brain Research, Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA.
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50
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Xu H, Chen R, Cai X, He D. Differential effects of activating D1 and D2 receptors on electrophysiology of neostriatal neurons in a rat model of Parkinson's disease induced by paraquat and maneb. Neurosci Res 2011; 71:411-20. [PMID: 21903142 DOI: 10.1016/j.neures.2011.08.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 07/29/2011] [Accepted: 08/22/2011] [Indexed: 12/21/2022]
Abstract
Neostriatum plays an important role in the pathophysiology of Parkinson's disease (PD). However, the changes of sensitivity of dopamine receptors of neostriatal neurons in PD have been less addressed in vivo. In the present study, systemic exposure to paraquat and maneb induced Parkinsonian symptoms and neuronal loss of substantia nigra pars compacta. Using single-unit recording methods, three types of neostriatal neurons were recorded including medium spiny-like neurons, large aspiny-like neurons and fast-spiking interneurons. In the exposed rats, increased firing activity of neostriatal neurons was revealed when compared to control rats. Following D1 receptor agonist, SKF38393 and D2 receptor agonist, LY171555 iontophoretically administrated respectively, effects of increase and decrease in firing activity were both observed in neostriatal neurons. However, stronger inhibitory effects of activating D1 receptors and weaker excitatory effects of activating D2 receptors were found in the exposed rats as compared to controls. It indicated that differential changes of sensitivity of D1 and D2 receptors in Parkinson's disease were related to the modulation of the imbalance between D1-receptor-dependent striatonigral direct pathway and D2-receptor-dependent striatopallidal indirect pathway. Our results illustrate the electrophysiological changes of in vivo neostriatal neurons in Parkinson's disease, thereby providing insight into the regulatory mechanisms of dopamine-mediated physiology.
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Affiliation(s)
- Haiyan Xu
- Lab of Neurotoxicology, Department of Environment Science, East China Normal University, Shanghai 200062, China
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