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Tan H, Du C, Zhang L, Guo Y, Yang Y, Sun Q, Zhang Q, Li L. Lesions of the lateral habenula excite dopamine neurons in the ventral tegmental area and serotonin neurons in the dorsal raphe nuclei in hemiparkinsonian rats. Brain Res 2024; 1835:148918. [PMID: 38588847 DOI: 10.1016/j.brainres.2024.148918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 03/20/2024] [Accepted: 04/05/2024] [Indexed: 04/10/2024]
Abstract
The lateral habenula (LHb) projects to the ventral tegmental area (VTA) and dorsal raphe nuclei (DRN) that deliver dopamine (DA) and serotonin (5-HT) to cortical and limbic regions such as the medial prefrontal cortex (mPFC), hippocampus and basolateral amygdala (BLA). Dysfunctions of VTA-related mesocorticolimbic dopaminergic and DRN-related serotonergic systems contribute to non-motor symptoms in Parkinson's disease (PD). However, how the LHb affects the VTA and DRN in PD remains unclear. Here, we used electrophysiological and neurochemical approaches to explore the effects of LHb lesions on the firing activity of VTA and DRN neurons, as well as the levels of DA and 5-HT in related brain regions in unilateral 6-hydroxydopamie (6-OHDA)-induced PD rats. We found that compared to sham lesions, lesions of the LHb increased the firing rate of DA neurons in the VTA and 5-HT neurons in the DRN, but decreased the firing rate of GABAergic neurons in the same nucleus. In addition, lesions of the LHb increased the levels of DA and 5-HT in the mPFC, ventral hippocampus and BLA compared to sham lesions. These findings suggest that lesions of the LHb enhance the activity of mesocorticolimbic dopaminergic and serotonergic systems in PD.
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Affiliation(s)
- Huihui Tan
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710004, China
| | - Chengxue Du
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710004, China
| | - Li Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, China
| | - Yuan Guo
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, China
| | - Yaxin Yang
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710004, China
| | - Qingfeng Sun
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710004, China
| | - Qiaojun Zhang
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710004, China.
| | - Libo Li
- Department of Rehabilitation Medicine, The Second Affiliated Hospital, Xi'an Jiaotong University, Xi'an 710004, China.
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2
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Lapish CC. Understanding How Acute Alcohol Impacts Neural Encoding in the Rodent Brain. Curr Top Behav Neurosci 2024. [PMID: 38858298 DOI: 10.1007/7854_2024_479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024]
Abstract
Alcohol impacts neural circuitry throughout the brain and has wide-ranging effects on the biophysical properties of neurons in these circuits. Articulating how these wide-ranging effects might eventually result in altered computational properties has the potential to provide a tractable working model of how alcohol alters neural encoding. This chapter reviews what is currently known about how acute alcohol influences neural activity in cortical, hippocampal, and dopaminergic circuits as these have been the primary focus of understanding how alcohol alters neural computation. While other neural systems have been the focus of exhaustive work on this topic, these brain regions are the ones where in vivo neural recordings are available, thus optimally suited to make the link between changes in neural activity and behavior. Rodent models have been key in developing an understanding of how alcohol impacts the function of these circuits, and this chapter therefore focuses on work from mice and rats. While progress has been made, it is critical to understand the challenges and caveats associated with experimental procedures, especially when performed in vivo, which are designed to answer this question and if/how to translate these data to humans. The hypothesis is discussed that alcohol impairs the ability of neural circuits to acquire states of neural activity that are transiently elevated and characterized by increased complexity. It is hypothesized that these changes are distinct from the traditional view of alcohol being a depressant of neural activity in the forebrain.
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Affiliation(s)
- Christopher C Lapish
- Department of Anatomy, Cell Biology, and Physiology, Stark Neuroscience Institute, Indiana University School of Medicine, Indianapolis, IN, USA.
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3
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Maal-Bared G, Yee M, Harding EK, Ghebreselassie M, Bergamini M, Choy R, Kim E, Di Vito S, Patel M, Amirzadeh M, Grieder TE, Coles BL, Nagy JI, Bonin RP, Steenland HW, van der Kooy D. Connexin-36-positive gap junctions in ventral tegmental area GABA neurons sustain opiate dependence. Eur J Neurosci 2024; 59:3422-3444. [PMID: 38679044 DOI: 10.1111/ejn.16366] [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: 05/17/2023] [Revised: 03/20/2024] [Accepted: 04/03/2024] [Indexed: 05/01/2024]
Abstract
Drug dependence is characterized by a switch in motivation wherein a positively reinforcing substance can become negatively reinforcing. Put differently, drug use can transform from a form of pleasure-seeking to a form of relief-seeking. Ventral tegmental area (VTA) GABA neurons form an anatomical point of divergence between two double dissociable pathways that have been shown to be functionally implicated and necessary for these respective motivations to seek drugs. The tegmental pedunculopontine nucleus (TPP) is necessary for opiate conditioned place preferences (CPP) in previously drug-naïve rats and mice, whereas dopaminergic (DA) transmission in the nucleus accumbens (NAc) is necessary for opiate CPP in opiate-dependent and withdrawn (ODW) rats and mice. Here, we show that this switch in functional anatomy is contingent upon the gap junction-forming protein, connexin-36 (Cx36), in VTA GABA neurons. Intra-VTA infusions of the Cx36 blocker, mefloquine, in ODW rats resulted in a reversion to a drug-naïve-like state wherein the TPP was necessary for opiate CPP and where opiate withdrawal aversions were lost. Consistent with these data, conditional knockout mice lacking Cx36 in GABA neurons (GAD65-Cre;Cx36 fl(CFP)/fl(CFP)) exhibited a perpetual drug-naïve-like state wherein opiate CPP was always DA independent, and opiate withdrawal aversions were absent even in mice subjected to an opiate dependence and withdrawal induction protocol. Further, viral-mediated rescue of Cx36 in VTA GABA neurons was sufficient to restore their susceptibility to an ODW state wherein opiate CPP was DA dependent. Our findings reveal a functional role for VTA gap junctions that has eluded prevailing circuit models of addiction.
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Affiliation(s)
- Geith Maal-Bared
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Mandy Yee
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Erika K Harding
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Martha Ghebreselassie
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Michael Bergamini
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Department of Human Biology, University of Toronto, Toronto, Ontario, Canada
| | - Roxanne Choy
- Department of Human Biology, University of Toronto, Toronto, Ontario, Canada
| | - Ethan Kim
- Department of Human Biology, University of Toronto, Toronto, Ontario, Canada
| | - Stephanie Di Vito
- Department of Human Biology, University of Toronto, Toronto, Ontario, Canada
| | - Maryam Patel
- Department of Human Biology, University of Toronto, Toronto, Ontario, Canada
| | - Mohammadreza Amirzadeh
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Taryn E Grieder
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Brenda L Coles
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - James I Nagy
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Robert P Bonin
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | | | - Derek van der Kooy
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
- Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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4
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Bogdańska-Chomczyk E, Równiak M, Huang ACW, Kozłowska A. Parvalbumin interneuron deficiency in the prefrontal and motor cortices of spontaneously hypertensive rats: an attention-deficit hyperactivity disorder animal model insight. Front Psychiatry 2024; 15:1359237. [PMID: 38600979 PMCID: PMC11005678 DOI: 10.3389/fpsyt.2024.1359237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 02/15/2024] [Indexed: 04/12/2024] Open
Abstract
Background Attention deficit hyperactivity disorder (ADHD) is characterized by impairments in developmental-behavioral inhibition, resulting in impulsivity and hyperactivity. Recent research has underscored cortical inhibition deficiencies in ADHD via the gamma-aminobutyric acid (GABA)ergic system, which is crucial for maintaining excitatory-inhibitory balance in the brain. This study explored postnatal changes in parvalbumin (PV) immunoreactivity, indicating GABAergic interneuron types, in the prefrontal (PFC) and motor (MC) cortices of spontaneously hypertensive rats (SHRs), an ADHD animal model. Methods Examining PV- positive (PV+) cells associated with dopamine D2 receptors (D2) and the impact of dopamine on GABA synthesis, we also investigated changes in the immunoreactivity of D2 and tyrosine hydroxylase (TH). Brain sections from 4- to 10-week-old SHRs and Wistar Kyoto rats (WKYs) were immunohistochemically analyzed, comparing PV+, D2+ cells, and TH+ fiber densities across age-matched SHRs and WKYs in specific PFC/MC regions. Results The results revealed significantly reduced PV+ cell density in SHRs: prelimbic (~20% less), anterior cingulate (~15% less), primary (~15% less), and secondary motor (~17% less) cortices. PV+ deficits coincided with the upregulation of D2 in prepubertal SHRs and the downregulation of TH predominantly in pubertal/postpubertal SHRs. Conclusion Reduced PV+ cells in various PFC regions could contribute to inattention/behavioral alterations in ADHD, while MC deficits could manifest as motor hyperactivity. D2 upregulation and TH deficits may impact GABA synthesis, exacerbating behavioral deficits in ADHD. These findings not only shed new light on ADHD pathophysiology but also pave the way for future research endeavors.
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Affiliation(s)
- Ewelina Bogdańska-Chomczyk
- Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, Olsztyn, Poland
| | - Maciej Równiak
- Department of Animal Anatomy and Physiology, Faculty of Biology and Biotechnology, University of Warmia and Mazury, Olsztyn, Poland
| | | | - Anna Kozłowska
- Department of Human Physiology and Pathophysiology, School of Medicine, University of Warmia and Mazury, Olsztyn, Poland
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Chen M, Liu F, Wen L, Hu X. Nonlinear relationship between CAN current and C a 2 + influx underpins synergistic action of muscarinic and NMDA receptors on bursts induction in midbrain dopaminergic neurons. Cogn Neurodyn 2022; 16:719-731. [PMID: 35603052 PMCID: PMC9120320 DOI: 10.1007/s11571-021-09740-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 10/08/2021] [Accepted: 10/19/2021] [Indexed: 12/29/2022] Open
Abstract
Bursting of midbrain dopamine (DA) neurons is believed to represent an important reward signal that instructs and reinforces goal-directed behaviors. In DA neurons, many afferents, including cholinergic and glutamatergic inputs, induce bursting, and it is suggested that a synergy exists between these afferents in bursting induction. However, the underlying mechanisms of the role and the synergy of muscarinic receptors (mAChRs) and NMDA receptors (NMDARs) in bursting induction remain unclear. Present work bestowed analysis using a mathematical model of DA neurons to demonstrate the underlying mechanisms. Activation of mAChRs, leading to rapid translocation of TRPC channels to cell surface, recruited C a 2 + -activated nonspecific (CAN) current ( I CAN ), meanwhile NMDARs excitation triggered C a 2 + influx, which induced the positive feedback loop of C a 2 + and I CAN , respectively, yielded a robust ramping depolarization with a superimposed high-frequency spiking. In some DA cells, neither NMDARs nor mAChRs induced positive feedback loop unless they were activated simultaneously to induce bursting. Our experimental results verified those theoretical findings. These together unveil the underlying mechanisms of the role and synergy of mAChRs and NMDARs in bursting induction emerge from the nonlinear relationship between C a 2 + influx and I CAN . Given the diverse and complex nature of neural circuitry and the DA neuron heterogeneity, our work provides new insights to understand specific afferents, the synergy between those afferents, and the differences in intrinsic excitability to be integrated by the bursting to accurately characterize the dopamine signals in the valances of reward and reinforcement, and a broad spectrum of neuropsychiatric disorders.
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Affiliation(s)
- Mengjiao Chen
- College of Life Sciences, Leshan Normal University, Leshan, 614000 China
- Key Laboratory of Sichuan Institute for Protecting Endangered Birds in the Southwest Mountains, Leshan Normal University, Leshan, 614000 China
- Key Laboratory of MOE for Modern Teaching Technology, Shaanxi Normal University, Xi’an, 710062 China
| | - Fangqing Liu
- College of Life Sciences, Leshan Normal University, Leshan, 614000 China
- Key Laboratory of Sichuan Institute for Protecting Endangered Birds in the Southwest Mountains, Leshan Normal University, Leshan, 614000 China
| | - Longying Wen
- College of Life Sciences, Leshan Normal University, Leshan, 614000 China
- Key Laboratory of Sichuan Institute for Protecting Endangered Birds in the Southwest Mountains, Leshan Normal University, Leshan, 614000 China
| | - Xia Hu
- College of Life Sciences, Leshan Normal University, Leshan, 614000 China
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6
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Distinct Temporal Structure of Nicotinic ACh Receptor Activation Determines Responses of VTA Neurons to Endogenous ACh and Nicotine. eNeuro 2020; 7:ENEURO.0418-19.2020. [PMID: 32737187 PMCID: PMC7470928 DOI: 10.1523/eneuro.0418-19.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 02/10/2020] [Accepted: 04/18/2020] [Indexed: 11/29/2022] Open
Abstract
The addictive component of tobacco, nicotine, acts via nicotinic acetylcholine receptors (nAChRs). The β2 subunit-containing nAChRs (β2-nAChRs) play a crucial role in the rewarding properties of nicotine and are particularly densely expressed in the mesolimbic dopamine (DA) system. Specifically, nAChRs directly and indirectly affect DA neurons in the ventral tegmental area (VTA). The understanding of ACh and nicotinic regulation of DA neuron activity is incomplete. By computational modeling, we provide mechanisms for several apparently contradictory experimental results. First, systemic knockout of β2-containing nAChRs drastically reduces DA neurons bursting, although the major glutamatergic (Glu) afferents that have been shown to evoke this bursting stay intact. Second, the most intuitive way to rescue this bursting—by re-expressing the nAChRs on VTA DA neurons—fails. Third, nAChR re-expression on VTA GABA neurons rescues bursting in DA neurons and increases their firing rate under the influence of ACh input, whereas nicotinic application results in the opposite changes in firing. Our model shows that, first, without ACh receptors, Glu excitation of VTA DA and GABA neurons remains balanced and GABA inhibition cancels the direct excitation. Second, re-expression of ACh receptors on DA neurons provides an input that impedes membrane repolarization and is ineffective in restoring firing of DA neurons. Third, the distinct responses to ACh and nicotine occur because of distinct temporal patterns of these inputs: pulsatile versus continuous. Altogether, this study highlights how β2-nAChRs influence coactivation of the VTA DA and GABA neurons required for motivation and saliency signals carried by DA neuron activity.
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7
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Ostroumov A, Wittenberg RE, Kimmey BA, Taormina MB, Holden WM, McHugh AT, Dani JA. Acute Nicotine Exposure Alters Ventral Tegmental Area Inhibitory Transmission and Promotes Diazepam Consumption. eNeuro 2020; 7:ENEURO.0348-19.2020. [PMID: 32102779 PMCID: PMC7082131 DOI: 10.1523/eneuro.0348-19.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 01/20/2020] [Accepted: 02/16/2020] [Indexed: 11/21/2022] Open
Abstract
Nicotine use increases the risk for subsequent abuse of other addictive drugs, but the biological basis underlying this risk remains largely unknown. Interactions between nicotine and other drugs of abuse may arise from nicotine-induced neural adaptations in the mesolimbic dopamine (DA) system, a common pathway for the reinforcing effects of many addictive substances. Previous work identified nicotine-induced neuroadaptations that alter inhibitory transmission in the ventral tegmental area (VTA). Here, we test whether nicotine-induced dysregulation of GABAergic signaling within the VTA increases the vulnerability for benzodiazepine abuse that has been reported in smokers. We demonstrate in rats that nicotine exposure dysregulates diazepam-induced inhibition of VTA GABA neurons and increases diazepam consumption. In VTA GABA neurons, nicotine impaired KCC2-mediated chloride extrusion, depolarized the GABAA reversal potential, and shifted the pharmacological effect of diazepam on GABA neurons from inhibition toward excitation. In parallel, nicotine-related alterations in GABA signaling observed ex vivo were associated with enhanced diazepam-induced inhibition of lateral VTA DA neurons in vivo Targeting KCC2 with the agonist CLP290 normalized diazepam-induced effects on VTA GABA transmission and reduced diazepam consumption following nicotine administration to the control level. Together, our results provide insights into midbrain circuit alterations resulting from nicotine exposure that contribute to the abuse of other drugs, such as benzodiazepines.
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Affiliation(s)
- Alexey Ostroumov
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Ruthie E Wittenberg
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Blake A Kimmey
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Madison B Taormina
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - William M Holden
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Albert T McHugh
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - John A Dani
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
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8
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Ostroumov A, Dani JA. Inhibitory Plasticity of Mesocorticolimbic Circuits in Addiction and Mental Illness. Trends Neurosci 2018; 41:898-910. [PMID: 30149979 PMCID: PMC6252277 DOI: 10.1016/j.tins.2018.07.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/12/2018] [Accepted: 07/31/2018] [Indexed: 12/19/2022]
Abstract
Behavioral adaptations occur through remodeling of brain circuits, as arising, for instance, from experience-dependent synaptic plasticity. Drugs of abuse and aversive stimuli, such as stress, act on the mesocorticolimbic system, dysregulating adaptive mechanisms and leading to a variety of aberrant behaviors associated with neuropsychiatric disorders. Until recently, research in the field has commonly focused on experience-dependent synaptic plasticity at excitatory synapses. However, there is growing evidence that synaptic plasticity within inhibitory circuits is an important contributor to maladaptive behaviors. We speculate that restoring normal inhibitory synaptic transmission is a promising therapeutic target for correcting some of the circuit abnormalities underlying neuropsychiatric disorders.
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Affiliation(s)
- Alexey Ostroumov
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, Philadelphia, PA 19104, USA.
| | - John A Dani
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School for Medicine, Philadelphia, PA 19104, USA.
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9
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Yang S, Wang J, Lin Q, Deng B, Wei X, Liu C, Li H. Cost-efficient FPGA implementation of a biologically plausible dopamine neural network and its application. Neurocomputing 2018. [DOI: 10.1016/j.neucom.2018.07.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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10
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di Volo M, Morozova EO, Lapish CC, Kuznetsov A, Gutkin B. Dynamical ventral tegmental area circuit mechanisms of alcohol-dependent dopamine release. Eur J Neurosci 2018; 50:2282-2296. [PMID: 30215874 DOI: 10.1111/ejn.14147] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 08/15/2018] [Accepted: 08/24/2018] [Indexed: 11/28/2022]
Abstract
A large body of data has identified numerous molecular targets through which ethanol (EtOH) acts on brain circuits. Yet how these multiple mechanisms interact to result in dysregulated dopamine (DA) release under the influence of alcohol in vivo remains unclear. In this manuscript, we delineate potential circuit-level mechanisms responsible for EtOH-dependent dysregulation of DA release from the ventral tegmental area (VTA) into its projection areas. For this purpose, we constructed a circuit model of the VTA that integrates realistic Glutamatergic (Glu) inputs and reproduces DA release observed experimentally. We modelled the concentration-dependent effects of EtOH on its principal VTA targets. We calibrated the model to reproduce the inverted U-shape dose dependence of DA neuron activity on EtOH concentration. The model suggests a primary role of EtOH-induced boost in the Ih and AMPA currents in the DA firing-rate/bursting increase. This is counteracted by potentiated GABA transmission that decreases DA neuron activity at higher EtOH concentrations. Thus, the model connects well-established in vitro pharmacological EtOH targets with its in vivo influence on neuronal activity. Furthermore, we predict that increases in VTA activity produced by moderate EtOH doses require partial synchrony and relatively low rates of the Glu afferents. We propose that the increased frequency of transient (phasic) DA peaks evoked by EtOH results from synchronous population bursts in VTA DA neurons. Our model predicts that the impact of acute ETOH on dopamine release is critically shaped by the structure of the cortical inputs to the VTA.
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Affiliation(s)
- Matteo di Volo
- Unité de Neurosciences, Information et Complexité, CNRS, Gif-sur-Yvette, France.,Group for Neural Theory, LNC INSERM U960, DEC Ecole Normale Superieure PSL University, Paris, France
| | | | - Christopher C Lapish
- Addiction Neuroscience Program, Indiana University - Purdue University Indianapolis, Indianapolis, IN, USA
| | - Alexey Kuznetsov
- Department of Mathematical Sciences, Indiana University - Purdue University Indianapolis, Indianapolis, IN, USA
| | - Boris Gutkin
- Group for Neural Theory, LNC INSERM U960, DEC Ecole Normale Superieure PSL University, Paris, France.,Center for Cognition and Decision Making, NRU HSE, Moscow, Russia
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11
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Zakharov DG, Krupa M, Gutkin BS, Kuznetsov AS. High-frequency forced oscillations in neuronlike elements. Phys Rev E 2018; 97:062211. [PMID: 30011467 DOI: 10.1103/physreve.97.062211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Indexed: 11/07/2022]
Abstract
We analyzed a generic relaxation oscillator under moderately strong forcing at a frequency much greater that the natural intrinsic frequency of the oscillator. Additionally, the forcing is of the same sign and, thus, has a nonzero average, matching neuroscience applications. We found that, first, the transition to high-frequency synchronous oscillations occurs mostly through periodic solutions with virtually no chaotic regimes present. Second, the amplitude of the high-frequency oscillations is large, suggesting an important role for these oscillations in applications. Third, the 1:1 synchronized solution may lose stability, and, contrary to other cases, this occurs at smaller, but not at higher frequency differences between intrinsic and forcing oscillations. We analytically built a map that gives an explanation of these properties. Thus, we found a way to substantially "overclock" the oscillator with only a moderately strong external force. Interestingly, in application to neuroscience, both excitatory and inhibitory inputs can force the high-frequency oscillations.
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Affiliation(s)
- D G Zakharov
- Institute of Applied Physics of RAS, 46 Ulyanov Str., Nizhny Novgorod, Russia
| | - M Krupa
- Laboratoire Jean-Alexandre Dieudonné, Université de Cote d'Azur, Nice, France
| | - B S Gutkin
- Group of Neural Theory, LNC INSERM U960, École Normale Supérieure PSL* University, 29 rue d'Ulm, Paris, France.,Centre for Cognition and Decision Making, National Research University Higher School of Economics, Myasnitskaya St. 20, Moscow, Russia
| | - A S Kuznetsov
- Department of Mathematical Sciences and Center for Mathematical Modeling and Computational Sciences, Indiana University-Purdue University Indianapolis, 402 N. Blackford St., Indianapolis, Indiana 46202, USA
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12
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Adrenergic Receptor Agonists’ Modulation of Dopaminergic and Non-dopaminergic Neurons in the Ventral Tegmental Area. Neuroscience 2018; 375:119-134. [DOI: 10.1016/j.neuroscience.2017.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 10/30/2017] [Accepted: 11/01/2017] [Indexed: 01/02/2023]
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13
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Kodirov SA. Addictive neurons. THERAPEUTIC TARGETS FOR NEUROLOGICAL DISEASES 2017; 4:e1498. [PMID: 28649663 PMCID: PMC5479441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Since the reward center is considered to be the area tegmentalis ventralis of the hypothalamus, logically its neurons could mainly be responsible for addiction. However, the literature asserts that almost any neurons of CNS can respond to one or another addictive compound. Obviously not only addictive nicotine, but also alcohol, amphetamine, cannabis, cocaine, heroin and morphine may influence dopaminergic cells alone in VTA. Moreover, paradoxically some of these drugs ameliorate symptoms, counterbalance syndromes, cure diseases and improve health, not only those related to the CNS and in adults, but also almost all other organs and in children, e.g. epilepsy.
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Affiliation(s)
- Sodikdjon A. Kodirov
- I. P. Pavlov Department of Physiology, State Research Institute of Experimental Medicine, Russian Academy of Medical Sciences, Saint Petersburg 197376, Russia
- University of Texas at Brownsville, Department of Biological Sciences, Texas 78520, USA
- Johannes Gutenberg University, 55099 Mainz, Germany
- Almazov Federal Heart, Blood and Endocrinology Centre, Saint Petersburg 197341, Russia
- Neuroscience Institute, Morehouse School of Medicine, Atlanta, GA 30310, USA
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14
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Morozova EO, Zakharov D, Gutkin BS, Lapish CC, Kuznetsov A. Dopamine Neurons Change the Type of Excitability in Response to Stimuli. PLoS Comput Biol 2016; 12:e1005233. [PMID: 27930673 PMCID: PMC5145155 DOI: 10.1371/journal.pcbi.1005233] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 11/02/2016] [Indexed: 11/18/2022] Open
Abstract
The dynamics of neuronal excitability determine the neuron's response to stimuli, its synchronization and resonance properties and, ultimately, the computations it performs in the brain. We investigated the dynamical mechanisms underlying the excitability type of dopamine (DA) neurons, using a conductance-based biophysical model, and its regulation by intrinsic and synaptic currents. Calibrating the model to reproduce low frequency tonic firing results in N-methyl-D-aspartate (NMDA) excitation balanced by γ-Aminobutyric acid (GABA)-mediated inhibition and leads to type I excitable behavior characterized by a continuous decrease in firing frequency in response to hyperpolarizing currents. Furthermore, we analyzed how excitability type of the DA neuron model is influenced by changes in the intrinsic current composition. A subthreshold sodium current is necessary for a continuous frequency decrease during application of a negative current, and the low-frequency "balanced" state during simultaneous activation of NMDA and GABA receptors. Blocking this current switches the neuron to type II characterized by the abrupt onset of repetitive firing. Enhancing the anomalous rectifier Ih current also switches the excitability to type II. Key characteristics of synaptic conductances that may be observed in vivo also change the type of excitability: a depolarized γ-Aminobutyric acid receptor (GABAR) reversal potential or co-activation of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) leads to an abrupt frequency drop to zero, which is typical for type II excitability. Coactivation of N-methyl-D-aspartate receptors (NMDARs) together with AMPARs and GABARs shifts the type I/II boundary toward more hyperpolarized GABAR reversal potentials. To better understand how altering each of the aforementioned currents leads to changes in excitability profile of DA neuron, we provide a thorough dynamical analysis. Collectively, these results imply that type I excitability in dopamine neurons might be important for low firing rates and fine-tuning basal dopamine levels, while switching excitability to type II during NMDAR and AMPAR activation may facilitate a transient increase in dopamine concentration, as type II neurons are more amenable to synchronization by mutual excitation.
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Affiliation(s)
- Ekaterina O. Morozova
- Department of Physics, Indiana University, Bloomington, Indiana, United States of America
- Department of Mathematical sciences, Indiana University - Purdue University, Indianapolis, Indiana, United States of America
- * E-mail:
| | | | - Boris S. Gutkin
- Group of Neural Theory, INSERM U960 LNC, IEC, Ecole Normale Superieure PSL University, Paris
- Center for Cognition and Decision Making, NRU HSE, Moscow, Russia
| | - Christopher C. Lapish
- Addiction Neuroscience Program, Indiana University - Purdue University, Indianapolis, Indiana, United States of America
| | - Alexey Kuznetsov
- Department of Mathematical sciences, Indiana University - Purdue University, Indianapolis, Indiana, United States of America
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