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Finszter CK, Kemecsei R, Zachar G, Ádám Á, Csillag A. Gestational VPA exposure reduces the density of juxtapositions between TH+ axons and calretinin or calbindin expressing cells in the ventrobasal forebrain of neonatal mice. Front Neuroanat 2024; 18:1426042. [PMID: 39026519 PMCID: PMC11254666 DOI: 10.3389/fnana.2024.1426042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Accepted: 06/19/2024] [Indexed: 07/20/2024] Open
Abstract
Gestational exposure to valproic acid (VPA) is a valid rodent model of human autism spectrum disorder (ASD). VPA treatment is known to bring about specific behavioral deficits of sociability, matching similar alterations in human autism. Previous quantitative morphometric studies from our laboratory showed a marked reduction and defasciculation of the mesotelencephalic dopaminergic pathway of VPA treated mice, along with a decrease in tissue dopamine in the nucleus accumbens (NAc), but not in the caudatoputamen (CPu). In the present study, the correlative distribution of tyrosine hydroxylase positive (TH+) putative axon terminals, presynaptic to the target neurons containing calretinin (CR) or calbindin (CB), was assessed using double fluorescent immunocytochemistry and confocal laser microscopy in two dopamine recipient forebrain regions, NAc and olfactory tubercle (OT) of neonatal mice (mothers injected with VPA on ED13.5, pups investigated on PD7). Representative image stacks were volumetrically analyzed for spatial proximity and abundance of presynaptic (TH+) and postsynaptic (CR+, CB+) structures with the help of an Imaris (Bitplane) software. In VPA mice, TH/CR juxtapositions were reduced in the NAc, whereas the TH/CB juxtapositions were impoverished in OT. Volume ratios of CR+ and CB+ elements remained unchanged in NAc, whereas that of CB+ was markedly reduced in OT; here the abundance of TH+ axons was also diminished. CR and CB were found to partially colocalize with TH in the VTA and SN. In VPA exposed mice, the abundance of CR+ (but not CB+) perikarya increased both in VTA and SN, however, this upregulation was not mirrored by an increase of the number of CR+/TH+ double labeled cells. The observed reduction of total CB (but not of CB+ perikarya) in the OT of VPA exposed animals signifies a diminished probability of synaptic contacts with afferent TH+ axons, presumably by reducing the available synaptic surface. Altered dopaminergic input to ventrobasal forebrain targets during late embryonic development will likely perturb the development and consolidation of neural and synaptic architecture, resulting in lasting changes of the neuronal patterning (detected here as reduced synaptic input to dopaminoceptive interneurons) in ventrobasal forebrain regions specifically involved in motivation and reward.
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Affiliation(s)
| | | | | | | | - András Csillag
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
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2
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Seiler JL, Zhuang X, Nelson AB, Lerner TN. Dopamine across timescales and cell types: Relevance for phenotypes in Parkinson's disease progression. Exp Neurol 2024; 374:114693. [PMID: 38242300 DOI: 10.1016/j.expneurol.2024.114693] [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: 09/12/2023] [Revised: 01/09/2024] [Accepted: 01/15/2024] [Indexed: 01/21/2024]
Abstract
Dopamine neurons in the substantia nigra pars compacta (SNc) synthesize and release dopamine, a critical neurotransmitter for movement and learning. SNc dopamine neurons degenerate in Parkinson's Disease (PD), causing a host of motor and non-motor symptoms. Here, we review recent conceptual advances in our basic understanding of the dopamine system - including our rapidly advancing knowledge of dopamine neuron heterogeneity - with special attention to their importance for understanding PD. In PD patients, dopamine neuron degeneration progresses from lateral SNc to medial SNc, suggesting clinically relevant heterogeneity in dopamine neurons. With technical advances in dopamine system interrogation, we can understand the relevance of this heterogeneity for PD progression and harness it to develop new treatments.
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Affiliation(s)
- Jillian L Seiler
- Department of Neuroscience, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
| | - Xiaowen Zhuang
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA; Weill Institute for Neuroscience, University of California San Francisco, San Francisco, CA, USA; Kavli Institute for Fundamental Neuroscience, University of California San Francisco, San Francisco, CA, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
| | - Alexandra B Nelson
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA; Neuroscience Graduate Program, University of California San Francisco, San Francisco, CA, USA; Weill Institute for Neuroscience, University of California San Francisco, San Francisco, CA, USA; Kavli Institute for Fundamental Neuroscience, University of California San Francisco, San Francisco, CA, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA.
| | - Talia N Lerner
- Department of Neuroscience, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Northwestern University Interdepartmental Neuroscience Program (NUIN), Evanston, IL, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA.
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3
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Mitra S, Basu S, Singh O, Srivastava A, Singru PS. Calcium-binding proteins typify the dopaminergic neuronal subtypes in the ventral tegmental area of zebra finch, Taeniopygia guttata. J Comp Neurol 2022; 530:2562-2586. [PMID: 35715989 DOI: 10.1002/cne.25352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 05/09/2022] [Accepted: 05/11/2022] [Indexed: 11/11/2022]
Abstract
Calcium-binding proteins (CBPs) regulate neuronal function in midbrain dopamine (DA)-ergic neurons in mammals by buffering and sensing the intracellular Ca2+ , and vesicular release. In birds, the equivalent set of neurons are important in song learning, directed singing, courtship, and energy balance, yet the status of CBPs in these neurons is unknown. Herein, for the first time, we probe the nature of CBPs, namely, Calbindin-, Calretinin-, Parvalbumin-, and Secretagogin-expressing DA neurons in the ventral tegmental area (VTA) and substantia nigra (SN) in the midbrain of zebra finch, Taeniopygia guttata. qRT-PCR analysis of ventral midbrain tissue fragment revealed higher Calbindin- and Calretinin-mRNA levels compared to Parvalbumin and Secretagogin. Application of immunofluorescence showed CBP-immunoreactive (-i) neurons in VTA (anterior [VTAa], mid [VTAm], caudal [VTAc]), SN (compacta [SNc], and reticulata [SNr]). Compared to VTAa, higher Calbindin- and Parvalbumin-immunoreactivity (-ir), and lower Calretinin-ir were observed in VTAm and VTAc. Secretagogin-ir was highly localized to VTAa. In SN, Calbindin- and Calretinin-ir were higher in SNc, SNr was Parvalbumin enriched, and Secretagogin-ir was not detected. Weak, moderate, and intense tyrosine hydroxylase (TH)-i VTA neurons were demarcated as subtypes 1, 2, and 3, respectively. While subtype 1 TH-i neurons were neither Calbindin- nor Calretinin-i, ∼80 and ∼65% subtype 2 and ∼30 and ∼45% subtype 3 TH-i neurons co-expressed Calbindin and Calretinin, respectively. All TH-i neuronal subtypes co-expressed Parvalbumin with reciprocal relationship with TH-ir. We suggest that the CBPs may determine VTA DA neuronal heterogeneity and differentially regulate their activity in T. guttata.
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Affiliation(s)
- Saptarsi Mitra
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India.,Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Sumela Basu
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India.,Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Omprakash Singh
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India.,Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Abhinav Srivastava
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India.,Homi Bhabha National Institute (HBNI), Mumbai, India
| | - Praful S Singru
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India.,Homi Bhabha National Institute (HBNI), Mumbai, India
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4
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Cai J, Tong Q. Anatomy and Function of Ventral Tegmental Area Glutamate Neurons. Front Neural Circuits 2022; 16:867053. [PMID: 35669454 PMCID: PMC9164627 DOI: 10.3389/fncir.2022.867053] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 03/30/2022] [Indexed: 11/29/2022] Open
Abstract
The ventral tegmental area (VTA) is well known for regulating reward consumption, learning, memory, and addiction behaviors through mediating dopamine (DA) release in downstream regions. Other than DA neurons, the VTA is known to be heterogeneous and contains other types of neurons, including glutamate neurons. In contrast to the well-studied and established functions of DA neurons, the role of VTA glutamate neurons is understudied, presumably due to their relatively small quantity and a lack of effective means to study them. Yet, emerging studies have begun to reveal the importance of glutamate release from VTA neurons in regulating diverse behavioral repertoire through a complex intra-VTA and long-range neuronal network. In this review, we summarize the features of VTA glutamate neurons from three perspectives, namely, cellular properties, neural connections, and behavioral functions. Delineation of VTA glutamatergic pathways and their interactions with VTA DA neurons in regulating behaviors may reveal previously unappreciated functions of the VTA in other physiological processes.
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Affiliation(s)
- Jing Cai
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, UTHealth McGovern Medical School, Houston, TX, United States
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, United States
| | - Qingchun Tong
- Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, UTHealth McGovern Medical School, Houston, TX, United States
- Neuroscience Program, The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, United States
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Logan CN, Rojas G, Wilkinson CS, Polo Escorcia AK, Reichel CM, Peris J, Knackstedt LA. Systemic oxytocin increases glutamate efflux in the nucleus accumbens core of cocaine-experienced male and female rats but only increases dopamine efflux in males. Behav Brain Res 2022; 417:113590. [PMID: 34551348 DOI: 10.1016/j.bbr.2021.113590] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 09/13/2021] [Accepted: 09/16/2021] [Indexed: 01/10/2023]
Abstract
Oxytocin attenuates cocaine-seeking when administered both systemically and directly into the nucleus accumbens core. This effect is blocked by intra-accumbens antagonism of mGlu2/3 and, together with our finding that intra-accumbens oxytocin increases glutamate concentrations in this brain region, indicates that pre-synaptic regulation of glutamate release by oxytocin influences cocaine relapse. However, mGlu2/3 receptors also regulate dopamine release in the nucleus accumbens. Here we aimed to determine whether systemic oxytocin increases glutamate and dopamine concentrations in the nucleus accumbens core of cocaine-experienced and cocaine-naïve male and female rats. A subset of rats self-administered cocaine (0.5 mg/kg/infusion) and then underwent extinction training for 2-3 weeks. Rats were implanted with microdialysis probes in the accumbens core and samples were collected for a baseline period, and following saline (1 mL/kg), and oxytocin (1 mg/kg, IP) injections. Locomotion was assessed during microdialysis. In cocaine-experienced rats, oxytocin increased glutamate concentrations in the accumbens core to the same extent in males and females but only increased dopamine concentrations in male rats. Oxytocin did not alter glutamate levels in cocaine-naïve rats. Oxytocin did not produce sedation. These results extend previous findings that systemic oxytocin increases nucleus accumbens dopamine in a sex-specific manner in cocaine-experienced rats. These data are the first to find that systemic oxytocin increases nucleus accumbens glutamate after cocaine experience, providing a mechanism of action by which oxytocin attenuates the reinstatement of cocaine seeking in both male and female rats.
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Affiliation(s)
- C N Logan
- Psychology Department, University of Florida, Gainesville, FL, USA; Center for Addiction Research and Education, University of Florida, Gainesville, FL, USA.
| | - G Rojas
- Psychology Department, University of Florida, Gainesville, FL, USA
| | - C S Wilkinson
- Psychology Department, University of Florida, Gainesville, FL, USA; Center for Addiction Research and Education, University of Florida, Gainesville, FL, USA
| | | | - C M Reichel
- Neuroscience Dept., Medical University of South Carolina, Charleston SC, USA
| | - J Peris
- Center for Addiction Research and Education, University of Florida, Gainesville, FL, USA; Pharmacodynamics Department, University of Florida, Gainesville, FL, USA
| | - L A Knackstedt
- Psychology Department, University of Florida, Gainesville, FL, USA; Center for Addiction Research and Education, University of Florida, Gainesville, FL, USA
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Abstract
Astroglia are key regulators of synaptic function, playing central roles in homeostatic ion buffering, energy dynamics, transmitter uptake, maintenance of neurotransmitter pools, and regulation of synaptic plasticity through release of neuroactive chemicals. Given the myriad of crucial homeostatic and signaling functions attributed to astrocytes and the variety of neurotransmitter receptors expressed by astroglia, they serve as prime cellular candidates for establishing maladaptive synaptic plasticity following drug exposure. Initial studies on astroglia and addiction have placed drug-mediated disruptions in the homeostatic regulation of glutamate as a central aspect of relapse vulnerability. However, the generation of sophisticated tools to study and manipulate astroglia have proven that the interaction between addictive substances, astroglia, and relapse-relevant synaptic plasticity extends far beyond the homeostatic regulation of glutamate. Here we present astroglial systems impacted by drug exposure and discuss how changes in astroglial biology contribute to addiction biology.
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7
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Pérez-Fernández J, Barandela M, Jiménez-López C. The Dopaminergic Control of Movement-Evolutionary Considerations. Int J Mol Sci 2021; 22:11284. [PMID: 34681941 PMCID: PMC8541398 DOI: 10.3390/ijms222011284] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/14/2021] [Accepted: 10/15/2021] [Indexed: 12/11/2022] Open
Abstract
Dopamine is likely the most studied modulatory neurotransmitter, in great part due to characteristic motor deficits in Parkinson's disease that arise after the degeneration of the dopaminergic neurons in the substantia nigra pars compacta (SNc). The SNc, together with the ventral tegmental area (VTA), play a key role modulating motor responses through the basal ganglia. In contrast to the large amount of existing literature addressing the mammalian dopaminergic system, comparatively little is known in other vertebrate groups. However, in the last several years, numerous studies have been carried out in basal vertebrates, allowing a better understanding of the evolution of the dopaminergic system, especially the SNc/VTA. We provide an overview of existing research in basal vertebrates, mainly focusing on lampreys, belonging to the oldest group of extant vertebrates. The lamprey dopaminergic system and its role in modulating motor responses have been characterized in significant detail, both anatomically and functionally, providing the basis for understanding the evolution of the SNc/VTA in vertebrates. When considered alongside results from other early vertebrates, data in lampreys show that the key role of the SNc/VTA dopaminergic neurons modulating motor responses through the basal ganglia was already well developed early in vertebrate evolution.
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Affiliation(s)
- Juan Pérez-Fernández
- Center for Biomedical Research (CINBIO), Neurocircuits Group, Department of Functional Biology and Health Sciences, Campus Universitario Lagoas, Marcosende, Universidade de Vigo, 36310 Vigo, Spain; (M.B.); (C.J.-L.)
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8
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Eskenazi D, Malave L, Mingote S, Yetnikoff L, Ztaou S, Velicu V, Rayport S, Chuhma N. Dopamine Neurons That Cotransmit Glutamate, From Synapses to Circuits to Behavior. Front Neural Circuits 2021; 15:665386. [PMID: 34093138 PMCID: PMC8170480 DOI: 10.3389/fncir.2021.665386] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/16/2021] [Indexed: 11/21/2022] Open
Abstract
Discovered just over 20 years ago, dopamine neurons have the ability to cotransmit both dopamine and glutamate. Yet, the functional roles of dopamine neuron glutamate cotransmission and their implications for therapeutic use are just emerging. This review article encompasses the current body of evidence investigating the functions of dopamine neurons of the ventral midbrain that cotransmit glutamate. Since its discovery in dopamine neuron cultures, further work in vivo confirmed dopamine neuron glutamate cotransmission across species. From there, growing interest has led to research related to neural functioning including roles in synaptic signaling, development, and behavior. Functional connectome mapping reveals robust connections in multiple forebrain regions to various cell types, most notably to cholinergic interneurons in both the medial shell of the nucleus accumbens and the lateral dorsal striatum. Glutamate markers in dopamine neurons reach peak levels during embryonic development and increase in response to various toxins, suggesting dopamine neuron glutamate cotransmission may serve neuroprotective roles. Findings from behavioral analyses reveal prominent roles for dopamine neuron glutamate cotransmission in responses to psychostimulants, in positive valence and cognitive systems and for subtle roles in negative valence systems. Insight into dopamine neuron glutamate cotransmission informs the pathophysiology of neuropsychiatric disorders such as addiction, schizophrenia and Parkinson Disease, with therapeutic implications.
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Affiliation(s)
- Daniel Eskenazi
- Department of Psychiatry, Columbia University, New York, NY, United States
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
| | - Lauren Malave
- Department of Psychiatry, Columbia University, New York, NY, United States
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
| | - Susana Mingote
- Department of Psychiatry, Columbia University, New York, NY, United States
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
- Neuroscience Initiative, Advanced Science Research Center, Graduate Center of The City University of New York, New York, NY, United States
| | - Leora Yetnikoff
- Department of Psychology, College of Staten Island, City University of New York, Staten Island, NY, United States
- CUNY Neuroscience Collaborative, The Graduate Center, City University of New York, New York, NY, United States
| | - Samira Ztaou
- Department of Psychiatry, Columbia University, New York, NY, United States
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
| | - Vlad Velicu
- Department of Psychiatry, Columbia University, New York, NY, United States
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
| | - Stephen Rayport
- Department of Psychiatry, Columbia University, New York, NY, United States
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
| | - Nao Chuhma
- Department of Psychiatry, Columbia University, New York, NY, United States
- Department of Molecular Therapeutics, New York State Psychiatric Institute, New York, NY, United States
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Ducrot C, Trudeau LÉ. The challenging diversity of neurons in the ventral tegmental area: A commentary of Miranda-Barrientos, J. et al., Eur J Neurosci 2021. Eur J Neurosci 2021; 54:4085-4087. [PMID: 33942393 DOI: 10.1111/ejn.15268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/10/2021] [Accepted: 04/29/2021] [Indexed: 11/27/2022]
Affiliation(s)
- Charles Ducrot
- Department of Pharmacology and Physiology, Department of Neurosciences, Faculty of Medicine, CNS Research Group (GRSNC), Université de Montréal, Montréal, QC, Canada
| | - Louis-Éric Trudeau
- Department of Pharmacology and Physiology, Department of Neurosciences, Faculty of Medicine, CNS Research Group (GRSNC), Université de Montréal, Montréal, QC, Canada
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
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Lerner TN, Holloway AL, Seiler JL. Dopamine, Updated: Reward Prediction Error and Beyond. Curr Opin Neurobiol 2021; 67:123-130. [PMID: 33197709 PMCID: PMC8116345 DOI: 10.1016/j.conb.2020.10.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 01/10/2023]
Abstract
Dopamine neurons have been intensely studied for their roles in reinforcement learning. A dominant theory of how these neurons contribute to learning is through the encoding of a reward prediction error (RPE) signal. Recent advances in dopamine research have added nuance to RPE theory by incorporating the ideas of sensory prediction error, distributional encoding, and belief states. Further nuance is likely to be added shortly by convergent lines of research on dopamine neuron diversity. Finally, a major challenge is to reconcile RPE theory with other current theories of dopamine function to account for dopamine's role in movement, motivation, and goal-directed planning.
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Affiliation(s)
- Talia N Lerner
- Feinberg School of Medicine and Department of Physiology, Northwestern University, Chicago, IL, USA; Northwestern University Interdepartmental Neuroscience Program, Chicago, IL, USA.
| | - Ashley L Holloway
- Feinberg School of Medicine and Department of Physiology, Northwestern University, Chicago, IL, USA; Northwestern University Interdepartmental Neuroscience Program, Chicago, IL, USA
| | - Jillian L Seiler
- Feinberg School of Medicine and Department of Physiology, Northwestern University, Chicago, IL, USA; Department of Psychology, University of Illinois at Chicago, Chicago, IL, USA
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Yamaguchi T, Ozawa H, Yamaguchi S, Hamaguchi S, Ueda S. Calbindin-Positive Neurons Co-express Functional Markers in a Location-Dependent Manner Within the A11 Region of the Rat Brain. Neurochem Res 2021; 46:853-865. [PMID: 33439431 DOI: 10.1007/s11064-020-03217-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 12/16/2020] [Accepted: 12/24/2020] [Indexed: 11/24/2022]
Abstract
The A11 region plays a role in numerous physiological functions, including pain and locomotor activity, and consists of a variety of neurons including GABAergic, calbindin positive (Calb+), and dopaminergic (DA) neurons. However, the neurochemical nature of Calb+ neurons and their regulatory role in the A11 region remain largely unknown. In this study, we examined the kind of functional markers co-expressed in the Calb+ neurons using sections from 8-week-old rats. To examine a marker related to classical neurotransmitters, we performed in situ hybridization for vesicular glutamate transporter 2 (vGluT2) or glutamate decarboxylase (GAD) 65 and 67, in conjunction with Calb immunohistochemistry. We found cellular co-expression of Calb with vGluT2 or GAD65/67 throughout the A11 region. Nearly all Calb+/GAD65/67+ neurons were found in the rostral-middle aspect of the A11 region. In contrast, Calb+/vGluT2+ neurons were found predominantly in the middle-caudal aspect of the A11 region. For receptors and neuropeptides, we performed immunohistochemistry for androgen receptor (AR), estrogen receptors (ERα and ERβ), and calcitonin gene-related peptide (CGRP). We found that Calb+ neurons co-expressed AR in the rostral aspect of the A11 region in both male and female rats. However, we rarely find cellular co-expression of Calb with ERα or ERβ in this region. For CGRP, we found both Calb+ neurons with or without CGRP expression. These results demonstrate that Calb+ neurons co-express many functional markers. Calb+ neurons have a distinct distribution pattern and may play a variety of regulatory roles, depending on their location within the A11 region.
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Affiliation(s)
- Tsuyoshi Yamaguchi
- Department of Histology and Neurobiology, Dokkyo Medical University, School of Medicine, 880 Kitakobayashi, Mibu-machi, Shimotsuga-gun, Tochigi, 321-0293, Japan.
| | - Hidechika Ozawa
- Department of Histology and Neurobiology, Dokkyo Medical University, School of Medicine, 880 Kitakobayashi, Mibu-machi, Shimotsuga-gun, Tochigi, 321-0293, Japan
- Department of Anesthesia and Pain Medicine, Dokkyo Medical University, School of Medicine, 880 Kitakobayashi, Mibu-machi, Shimotsuga-gun, Tochigi, 321-0293, Japan
| | - Shigeki Yamaguchi
- Department of Anesthesia and Pain Medicine, Dokkyo Medical University, School of Medicine, 880 Kitakobayashi, Mibu-machi, Shimotsuga-gun, Tochigi, 321-0293, Japan
| | - Shinsuke Hamaguchi
- Department of Anesthesia and Pain Medicine, Dokkyo Medical University, School of Medicine, 880 Kitakobayashi, Mibu-machi, Shimotsuga-gun, Tochigi, 321-0293, Japan
| | - Shuichi Ueda
- Department of Histology and Neurobiology, Dokkyo Medical University, School of Medicine, 880 Kitakobayashi, Mibu-machi, Shimotsuga-gun, Tochigi, 321-0293, Japan
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Dong W, Luo B, Qiu C, Jiang X, Shen B, Zhang L, Liu W, Zhang W. TRIM3 attenuates apoptosis in Parkinson's disease via activating PI3K/AKT signal pathway. Aging (Albany NY) 2020; 13:735-749. [PMID: 33253119 PMCID: PMC7835008 DOI: 10.18632/aging.202181] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 10/15/2020] [Indexed: 04/14/2023]
Abstract
This article aims to study tripartite motif-containing protein 3 (TRIM3) effects on Parkinson's disease (PD). TRIM3 expression in venous blood of PD patients was detected by qRT-PCR. PD mouse model and PD SH-SY5Y cell model were constructed. PD cells were treated by LY294002 (a PI3K inhibitor). The apoptosis of PD mouse midbrain was detected. Glutathione (GSH) and superoxide dismutase (SOD) level in PD cells and mice midbrain was analyzed. Intracellular reactive oxygen species (ROS) and MMP were detected. The effect of TRIM3 on cell viability, apoptosis and PI3K/AKT signal pathway were analyzed. As a result, TRIM3 expression in venous blood of PD patients was decreased. TRIM3 up-regulation in PD mouse decreased midbrain tissues apoptosis. TRIM3 up-regulation increased GSH and SOD levels in PD mice midbrain tissues and PD cells. TRIM3 up-regulation in PD cells prominently reduced ROS and MMP. TRIM3 up-regulation increased PD cells viability and decreased apoptosis. TRIM3 up-regulation in PD cells elevated Bcl-2 protein expression and weakened Bax, Cleaved-caspase 3 and Cleaved-caspase 9 proteins expression. TRIM3 up-regulation increased p-PI3K/PI3K and p-AKT/AKT ratio. PI3K inhibitor treatment reversed the inhibitory effect of TRIM3 up-regulation on PD cells apoptosis. Thus, TRIM3 might attenuate apoptosis in PD via activating PI3K/AKT signal pathway.
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Affiliation(s)
- Wenwen Dong
- Department of Functional Neurosurgery, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
| | - Bei Luo
- Department of Functional Neurosurgery, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
| | - Chang Qiu
- Department of Functional Neurosurgery, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
| | - Xu Jiang
- Neurology Department, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
| | - Bo Shen
- Neurology Department, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
| | - Li Zhang
- Neurology Department, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
| | - Weiguo Liu
- Neurology Department, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
| | - Wenbin Zhang
- Department of Functional Neurosurgery, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
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König N, Bimpisidis Z, Dumas S, Wallén-Mackenzie Å. Selective Knockout of the Vesicular Monoamine Transporter 2 ( Vmat2) Gene in Calbindin2/Calretinin-Positive Neurons Results in Profound Changes in Behavior and Response to Drugs of Abuse. Front Behav Neurosci 2020; 14:578443. [PMID: 33240055 PMCID: PMC7680758 DOI: 10.3389/fnbeh.2020.578443] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 10/09/2020] [Indexed: 11/16/2022] Open
Abstract
The vesicular monoamine transporter 2 (VMAT2) has a range of functions in the central nervous system, from sequestering toxins to providing conditions for the quantal release of monoaminergic neurotransmitters. Monoamine signaling regulates diverse functions from arousal to mood, movement, and motivation, and dysregulation of VMAT2 function is implicated in various neuropsychiatric diseases. While all monoamine-releasing neurons express the Vmat2 gene, only a subset is positive for the calcium-binding protein Calbindin 2 (Calb2; aka Calretinin, 29 kDa Calbindin). We recently showed that about half of the dopamine neurons in the mouse midbrain are positive for Calb2 and that Calb2 is an early developmental marker of midbrain dopamine cells. Calb2-positive neurons have also been identified in other monoaminergic areas, yet the role of Calb2-positive monoaminergic neurons is poorly understood. To selectively address the impact of Calb2-positive monoaminergic neurons in behavioral regulation, we took advantage of the Cre-LoxP system to create a new conditional knockout (cKO) mouse line in which Vmat2 expression is deleted selectively in Calb2-Cre-positive neurons. In this Vmat2lox/lox;Calb2−Cre cKO mouse line, gene targeting of Vmat2 was observed in several distinct monoaminergic areas. By comparing control and cKO mice in a series of behavioral tests, specific dissimilarities were identified. In particular, cKO mice were smaller than control mice and showed heightened sensitivity to the stereotypy-inducing effects of amphetamine and slight reductions in preference toward sucrose and ethanol, as well as a blunted response in the elevated plus maze test. These data uncover new knowledge about the role of genetically defined subtypes of neurons in the brain’s monoaminergic systems.
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Affiliation(s)
- Niclas König
- Unit of Comparative Physiology, Department of Organismal Biology, Uppsala University, Uppsala, Sweden
| | - Zisis Bimpisidis
- Unit of Comparative Physiology, Department of Organismal Biology, Uppsala University, Uppsala, Sweden
| | | | - Åsa Wallén-Mackenzie
- Unit of Comparative Physiology, Department of Organismal Biology, Uppsala University, Uppsala, Sweden
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14
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Dore R, Krotenko R, Reising JP, Murru L, Sundaram SM, Di Spiezio A, Müller-Fielitz H, Schwaninger M, Jöhren O, Mittag J, Passafaro M, Shanabrough M, Horvath TL, Schulz C, Lehnert H. Nesfatin-1 decreases the motivational and rewarding value of food. Neuropsychopharmacology 2020; 45:1645-1655. [PMID: 32353862 PMCID: PMC7419560 DOI: 10.1038/s41386-020-0682-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 12/12/2022]
Abstract
Homeostatic and hedonic pathways distinctly interact to control food intake. Dysregulations of circuitries controlling hedonic feeding may disrupt homeostatic mechanisms and lead to eating disorders. The anorexigenic peptides nucleobindin-2 (NUCB2)/nesfatin-1 may be involved in the interaction of these pathways. The endogenous levels of this peptide are regulated by the feeding state, with reduced levels following fasting and normalized by refeeding. The fasting state is associated with biochemical and behavioral adaptations ultimately leading to enhanced sensitization of reward circuitries towards food reward. Although NUCB2/nesfatin-1 is expressed in reward-related brain areas, its role in regulating motivation and preference for nutrients has not yet been investigated. We here report that both dopamine and GABA neurons express NUCB2/nesfatin-1 in the VTA. Ex vivo electrophysiological recordings show that nesfatin-1 hyperpolarizes dopamine, but not GABA, neurons of the VTA by inducing an outward potassium current. In vivo, central administration of nesfatin-1 reduces motivation for food reward in a high-effort condition, sucrose intake and preference. We next adopted a 2-bottle choice procedure, whereby the reward value of sucrose was compared with that of a reference stimulus (sucralose + optogenetic stimulation of VTA dopamine neurons) and found that nesfatin-1 fully abolishes the fasting-induced increase in the reward value of sucrose. These findings indicate that nesfatin-1 reduces energy intake by negatively modulating dopaminergic neuron activity and, in turn, hedonic aspects of food intake. Since nesfatin-1´s actions are preserved in conditions of leptin resistance, the present findings render the NUCB2/nesfatin-1 system an appealing target for the development of novel therapeutical treatments towards obesity.
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Affiliation(s)
- Riccardo Dore
- Department of Internal Medicine I, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany. .,Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany.
| | - Regina Krotenko
- grid.4562.50000 0001 0057 2672Department of Internal Medicine I, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Jan Philipp Reising
- grid.4562.50000 0001 0057 2672Department of Internal Medicine I, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4714.60000 0004 1937 0626Present Address: Department of Women’s and Children’s Health, Karolinska Institutet, 171 76 Stockholm, Sweden
| | - Luca Murru
- grid.418879.b0000 0004 1758 9800CNR, Institute of Neuroscience, 20129 Milan, Italy
| | - Sivaraj Mohana Sundaram
- grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Alessandro Di Spiezio
- grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.9764.c0000 0001 2153 9986Present Address: Department of Biochemistry, University of Kiel, 24118 Kiel, Germany
| | - Helge Müller-Fielitz
- grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Markus Schwaninger
- grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Olaf Jöhren
- grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Jens Mittag
- grid.4562.50000 0001 0057 2672Department of Internal Medicine I, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Maria Passafaro
- grid.418879.b0000 0004 1758 9800CNR, Institute of Neuroscience, 20129 Milan, Italy
| | - Marya Shanabrough
- grid.47100.320000000419368710Department of Comparative Medicine, Program on Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520 USA
| | - Tamas L. Horvath
- grid.47100.320000000419368710Department of Comparative Medicine, Program on Integrative Cell Signaling and Neurobiology of Metabolism, Yale University School of Medicine, New Haven, CT 06520 USA ,grid.483037.b0000 0001 2226 5083Department of Anatomy and Histology, University of Veterinary Medicine, Budapest, H-1078 Hungary
| | - Carla Schulz
- grid.4562.50000 0001 0057 2672Department of Internal Medicine I, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
| | - Hendrik Lehnert
- grid.4562.50000 0001 0057 2672Department of Internal Medicine I, University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany ,grid.4562.50000 0001 0057 2672Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Ratzeburger Allee 160, 23562 Lübeck, Germany
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15
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Bhaskar S, Gowda J, Prasanna J, Kumar A. Does altering proteasomal activity and trafficking reduce the arborization mediated specific vulnerability of SNpc dopaminergic neurons of Parkinson's disease? Med Hypotheses 2020; 143:110062. [PMID: 32652429 DOI: 10.1016/j.mehy.2020.110062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/27/2020] [Indexed: 01/15/2023]
Abstract
Parkinson's disease (PD) is a late-onset degenerative neuronal disorder and stands second among the neurological disorders with 1% of the total world population being affected. The disease originates majorly due to compromised function of the dopaminergic (DA) neurons in the Substantia Nigra pars compacta (SNpc), but not the ventral tegmental area (VTA) region of the midbrain. The differential susceptibility for degeneration is majorly attributed to morphological, molecular, and electrophysiological heterogeneity existing in DA neurons of SNpc and VTA. Long-range axonal arborization and a higher number of synapses in SNpc DA neurons make it more vulnerable compared to VTA DA neurons. Studies have shown that a decrease in such axonal arborization places DA neurons at decreased risk in PD. The two well established underlying mechanisms are a) As arborization is an energy-demanding process, increased redistribution of mitochondria to the axonal terminals occurs to satisfy the bioenergetic requirement b) The stabilization of axon-promoting factors at the axonal tip is an essential component for enhancing the arborization process. Interfering with any of these two processes would probably alleviate the degeneration of SNpc DA neurons. To accomplish the decreased stability of arborizing factors and thereby increase the resilience of SNpc DA neurons, we hypothesize the activation of anterograde transport-dependent recruitment of proteasomes to axon terminals as one of the most favorable approaches. Understanding this putative avenue of enhancing proteasomal activity and migration to the axonal tip could provide insight into the progression of neurodegeneration in PD and possibly offer a novel therapeutic strategy.
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Affiliation(s)
- Smitha Bhaskar
- Manipal Institute of Regenerative Medicine, Manipal Academy of Higher Education, Allalsandra, Yelahanka, Bengaluru 560065, Karnataka, India
| | - Jeevan Gowda
- Manipal Institute of Regenerative Medicine, Manipal Academy of Higher Education, Allalsandra, Yelahanka, Bengaluru 560065, Karnataka, India
| | - Jyothi Prasanna
- Manipal Institute of Regenerative Medicine, Manipal Academy of Higher Education, Allalsandra, Yelahanka, Bengaluru 560065, Karnataka, India
| | - Anujith Kumar
- Manipal Institute of Regenerative Medicine, Manipal Academy of Higher Education, Allalsandra, Yelahanka, Bengaluru 560065, Karnataka, India.
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16
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Zhang L, Hernández VS, Zetter MA, Eiden LE. VGLUT-VGAT expression delineates functionally specialised populations of vasopressin-containing neurones including a glutamatergic perforant path-projecting cell group to the hippocampus in rat and mouse brain. J Neuroendocrinol 2020; 32:e12831. [PMID: 31944441 DOI: 10.1111/jne.12831] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 01/10/2020] [Accepted: 01/10/2020] [Indexed: 11/27/2022]
Abstract
The origin and functional significance of vasopressin (AVP)-containing fibres in limbic regions has been an ongoing subject of investigation for several years. We have previously identified AVP-magnocellular neurones of rat hypothalamus that provide glutamatergic projections to the hippocampus, amygdala, lateral habenula and locus coeruleus. However, we also reported AVP-immunopositive fibres in those regions that are thin and make Gray type II synapses, which are unlikely to be of magnocellular origin. Therefore, in the present study, we characterised AVP mRNA co-expression with expression of mRNAs marking glutamatergic (vesicular glutamate transporter [VGLUT]) and GABAergic (vesicular GABA transporter [VGAT]) neuronal traits in rat and mouse brain, using high-resolution in situ hybridisation methods, including a radio-ribonucleotide and RNAscope 2.5 HD duplex assay, with Slc17a7, Slc17a6, Slc32a1 and Avp probes corresponding to mRNAs of VGLUT1, VGLUT2, VGAT and AVP, respectively. We located 18 cell groups expressing Avp and identified their molecular signatures for VGLUT and VGAT mRNA expression. Avp cell groups of hypothalamus and midbrain are mainly VGLUT mRNA-expressing, whereas those in regions derived from cerebral nuclei are mainly VGAT mRNA-expressing, suggesting a functional segregation of glutamate/GABA co-transmission with AVP. A newly identified Slc17a7 and Slc17a6 (but not Slc32a1) expressing vasopressinergic cell group was found in layer II-III neurones of the central entorhinal cortex, which projects to the hippocampus. These data support the notion of a complex role for AVP with respect to modulating multiple central circuits controlling behaviour in specific ways depending on co-transmission with glutamate or GABA, potentially giving rise to a functional classification of AVPergic neurones in the central nervous system.
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Affiliation(s)
- Limei Zhang
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Section on Molecular Neuroscience, National Institute of Mental Heath-Intramural Research Program, NIH, Bethesda, MD, USA
| | - Vito S Hernández
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Mario A Zetter
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ), Mexico City, Mexico
| | - Lee E Eiden
- Section on Molecular Neuroscience, National Institute of Mental Heath-Intramural Research Program, NIH, Bethesda, MD, USA
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17
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Yan Y, Beckley NA, Kim VJ, Drenan RM. Differential Nicotinic Modulation of Glutamatergic and GABAergic VTA Microcircuits. eNeuro 2019; 6:ENEURO.0298-19.2019. [PMID: 31744841 PMCID: PMC6893235 DOI: 10.1523/eneuro.0298-19.2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/01/2019] [Accepted: 10/30/2019] [Indexed: 12/12/2022] Open
Abstract
Ventral tegmental area (VTA) neurons receive glutamatergic and/or GABAergic input from other local neurons within the VTA. Nicotinic acetylcholine receptor (nAChR) activity is capable of modulating such intra-VTA transmission, but the mechanisms are unclear. Here, we isolated monosynaptic glutamate or GABA transmission from mouse medial VTA (mVTA) to lateral VTA (latVTA) using pharmacology and optogenetics, and we studied the ability of nicotine to modulate these modes of transmission. The action of nicotine on mVTA to latVTA glutamate transmission was bidirectional; nicotine enhanced glutamate release in half of the recorded latVTA cells and inhibited release in the other half. Nicotine-mediated reduction in glutamate release was reversed by blockade of GABAA receptors. This, coupled with expression data demonstrating coexpression of vesicular glutamate transporter 2 (VGluT2) and glutamate decarboxylase 2 (Gad2) in mVTA neurons, suggests that nicotine is able to stimulate GABA corelease from mVTA VGluT2+ neurons. Nicotine had an altogether different effect on mVTA to latVTA GABA release from Gad2+ cells; nicotine suppressed GABA release from mVTA Gad2+ terminals in nearly all cells tested. Together, these data uncover a complex system of local circuitry in the VTA that is modulated by nAChR activity. These actions of nicotine, which occurred at concentrations of nicotine found in the artificial CSF of cigarette smokers, may play a role in the adaptive response of the reward system to repeated nicotine exposure.
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Affiliation(s)
- Yijin Yan
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Nicole A Beckley
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27101
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Veronica J Kim
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Ryan M Drenan
- Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27101
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
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