1
|
Oriol L, Chao M, Kollman GJ, Dowlat DS, Singhal SM, Steinkellner T, Hnasko TS. Ventral tegmental area interneurons revisited: GABA and glutamate projection neurons make local synapses. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.07.597996. [PMID: 38895464 PMCID: PMC11185768 DOI: 10.1101/2024.06.07.597996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
The ventral tegmental area (VTA) contains projection neurons that release the neurotransmitters dopamine, GABA, and/or glutamate from distal synapses. VTA also contains GABA neurons that synapse locally on to VTA dopamine neurons, synapses widely credited to a population of so-called VTA interneurons. Interneurons in cortex, striatum, and elsewhere have well-defined morphological features, physiological properties, and molecular markers, but such features have not been clearly described in VTA. Indeed, there is scant evidence that local and distal synapses originate from separate populations of VTA GABA neurons. In this study we tested whether several markers expressed in non-dopamine VTA neurons are selective markers of interneurons, defined as neurons that synapse locally but not distally. Challenging previous assumptions, we found that VTA neurons genetically defined by expression of parvalbumin, somatostatin, neurotensin, or mu-opioid receptor project to known VTA targets including nucleus accumbens, ventral pallidum, lateral habenula, and prefrontal cortex. Moreover, we provide evidence that VTA GABA and glutamate projection neurons make functional inhibitory or excitatory synapses locally within VTA. These findings suggest that local collaterals of VTA projection neurons could mediate functions prior attributed to VTA interneurons. This study underscores the need for a refined understanding of VTA connectivity to explain how heterogeneous VTA circuits mediate diverse functions related to reward, motivation, or addiction.
Collapse
Affiliation(s)
- Lucie Oriol
- Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Melody Chao
- Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Grace J Kollman
- Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Dina S Dowlat
- Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Sarthak M Singhal
- Department of Neurosciences, University of California, San Diego, La Jolla, United States
| | - Thomas Steinkellner
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, Austria
| | - Thomas S Hnasko
- Department of Neurosciences, University of California, San Diego, La Jolla, United States
- Research Service VA San Diego Healthcare System, San Diego, United States
| |
Collapse
|
2
|
Faget L, Oriol L, Lee WC, Zell V, Sargent C, Flores A, Hollon NG, Ramanathan D, Hnasko TS. Ventral pallidum GABA and glutamate neurons drive approach and avoidance through distinct modulation of VTA cell types. Nat Commun 2024; 15:4233. [PMID: 38762463 PMCID: PMC11102457 DOI: 10.1038/s41467-024-48340-y] [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: 05/19/2023] [Accepted: 04/26/2024] [Indexed: 05/20/2024] Open
Abstract
The ventral pallidum (VP) contains GABA and glutamate neurons projecting to ventral tegmental area (VTA) whose stimulation drives approach and avoidance, respectively. Yet little is known about the mechanisms by which VP cell types shape VTA activity and drive behavior. Here, we found that both VP GABA and glutamate neurons were activated during approach to reward or by delivery of an aversive stimulus. Stimulation of VP GABA neurons inhibited VTA GABA, but activated dopamine and glutamate neurons. Remarkably, stimulation-evoked activation was behavior-contingent such that VTA recruitment was inhibited when evoked by the subject's own action. Conversely, VP glutamate neurons activated VTA GABA, as well as dopamine and glutamate neurons, despite driving aversion. However, VP glutamate neurons evoked dopamine in aversion-associated ventromedial nucleus accumbens (NAc), but reduced dopamine release in reward-associated dorsomedial NAc. These findings show how heterogeneous VP projections to VTA can be engaged to shape approach and avoidance behaviors.
Collapse
Affiliation(s)
- Lauren Faget
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA.
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA.
| | - Lucie Oriol
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Wen-Chun Lee
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Vivien Zell
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Cody Sargent
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Andrew Flores
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
| | - Nick G Hollon
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
| | - Dhakshin Ramanathan
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA
- Department of Psychiatry, University of California, San Diego, La Jolla, CA, USA
| | - Thomas S Hnasko
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA.
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA.
| |
Collapse
|
3
|
Geisler CE, Décarie-Spain L, Loh MK, Trumbauer W, Gaisinsky J, Klug ME, Pelletier C, Davis JF, Schmidt HD, Roitman MF, Kanoski SE, Hayes MR. Amylin Modulates a Ventral Tegmental Area-to-Medial Prefrontal Cortex Circuit to Suppress Food Intake and Impulsive Food-Directed Behavior. Biol Psychiatry 2024; 95:938-950. [PMID: 37517705 DOI: 10.1016/j.biopsych.2023.07.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 06/23/2023] [Accepted: 07/10/2023] [Indexed: 08/01/2023]
Abstract
BACKGROUND A better understanding of the neural mechanisms regulating impaired satiety to palatable foods is essential to treat hyperphagia linked with obesity. The satiation hormone amylin signals centrally at multiple nuclei including the ventral tegmental area (VTA). VTA-to-medial prefrontal cortex (mPFC) projections encode food reward information to influence behaviors including impulsivity. We hypothesized that modulation of VTA-to-mPFC neurons underlies amylin-mediated decreases in palatable food-motivated behaviors. METHODS We used a variety of pharmacological, behavioral, genetic, and viral approaches (n = 4-16/experiment) to investigate the anatomical and functional circuitry of amylin-controlled VTA-to-mPFC signaling in rats. RESULTS To first establish that VTA amylin receptor (calcitonin receptor) activation can modulate mPFC activity, we showed that intra-VTA amylin decreased food-evoked mPFC cFos. VTA amylin delivery also attenuated food-directed impulsive behavior, implicating VTA amylin signaling as a regulator of mPFC functions. Palatable food activates VTA dopamine and mPFC neurons. Accordingly, dopamine receptor agonism in the mPFC blocked the hypophagic effect of intra-VTA amylin, and VTA amylin injection reduced food-evoked phasic dopamine levels in the mPFC, supporting the idea that VTA calcitonin receptor activation decreases dopamine release in the mPFC. Surprisingly, calcitonin receptor expression was not found on VTA-to-mPFC projecting neurons but was instead found on GABAergic (gamma-aminobutyric acidergic) interneurons in the VTA that provide monosynaptic inputs to this pathway. Blocking intra-VTA GABA signaling, through GABA receptor antagonists and DREADD (designer receptor exclusively activated by designer drugs)-mediated GABAergic neuronal silencing, attenuated intra-VTA amylin-induced hypophagia. CONCLUSIONS These results indicate that VTA amylin signaling stimulates GABA-mediated inhibition of dopaminergic projections to the mPFC to mitigate impulsive consumption of palatable foods.
Collapse
Affiliation(s)
- Caroline E Geisler
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Léa Décarie-Spain
- Department of Biological Sciences, Human and Evolutionary Biology Section, University of Southern California, Los Angeles, California
| | - Maxine K Loh
- Department of Psychology, University of Illinois at Chicago, Chicago, Illinois
| | - Wolf Trumbauer
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jane Gaisinsky
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Molly E Klug
- Department of Biological Sciences, Human and Evolutionary Biology Section, University of Southern California, Los Angeles, California
| | - Caitlyn Pelletier
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Jon F Davis
- Novo Nordisk Research Center Seattle, Seattle, Washington
| | - Heath D Schmidt
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Mitchell F Roitman
- Department of Psychology, University of Illinois at Chicago, Chicago, Illinois
| | - Scott E Kanoski
- Department of Biological Sciences, Human and Evolutionary Biology Section, University of Southern California, Los Angeles, California
| | - Matthew R Hayes
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Biobehavioral Health Sciences, School of Nursing, University of Pennsylvania, Philadelphia, Pennsylvania.
| |
Collapse
|
4
|
Cid-Jofré V, Bahamondes T, Zúñiga Correa A, Ahumada Arias I, Reyes-Parada M, Renard GM. Psychostimulants and social behaviors. Front Pharmacol 2024; 15:1364630. [PMID: 38725665 PMCID: PMC11079219 DOI: 10.3389/fphar.2024.1364630] [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: 01/02/2024] [Accepted: 04/01/2024] [Indexed: 05/12/2024] Open
Abstract
Mounting evidence from animal models and human studies indicates that psychostimulants can significantly affect social behaviors. This is not surprising considering that the neural circuits underlying the regulation and expression of social behaviors are highly overlapped with those targeted by psychostimulants, which in most cases have strong rewarding and, consequently, addictive properties. In the present work, we provide an overview regarding the effects of illicit and prescription psychostimulants, such as cocaine, amphetamine-type stimulants, methylphenidate or modafinil, upon social behaviors such as social play, maternal behavior, aggression, pair bonding and social cognition and how psychostimulants in both animals and humans alter them. Finally, we discuss why these effects can vary depending on numerous variables such as the type of drug considered, acute versus long-term use, clinical versus recreational consumption, or the presence or absence of concomitant risk factors.
Collapse
Affiliation(s)
- Valeska Cid-Jofré
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Tamara Bahamondes
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Agustina Zúñiga Correa
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Ivalú Ahumada Arias
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Miguel Reyes-Parada
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile (USACH), Santiago, Chile
- Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Talca, Chile
| | - Georgina M. Renard
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile (USACH), Santiago, Chile
| |
Collapse
|
5
|
Palmer D, Cayton CA, Scott A, Lin I, Newell B, Paulson A, Weberg M, Richard JM. Ventral pallidum neurons projecting to the ventral tegmental area reinforce but do not invigorate reward-seeking behavior. Cell Rep 2024; 43:113669. [PMID: 38194343 PMCID: PMC10865898 DOI: 10.1016/j.celrep.2023.113669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 11/02/2023] [Accepted: 12/26/2023] [Indexed: 01/10/2024] Open
Abstract
Reward-predictive cues acquire motivating and reinforcing properties that contribute to the escalation and relapse of drug use in addiction. The ventral pallidum (VP) and ventral tegmental area (VTA) are two key nodes in brain reward circuitry implicated in addiction and cue-driven behavior. In the current study, we use in vivo fiber photometry and optogenetics to record from and manipulate VP→VTA in rats performing a discriminative stimulus task to determine the role these neurons play in invigoration and reinforcement by reward cues. We find that VP→VTA neurons are active during reward consumption and that optogenetic stimulation of these neurons biases choice behavior and is reinforcing. Critically, we find no encoding of reward-seeking vigor, and optogenetic stimulation does not enhance the probability or vigor of reward seeking in response to cues. Our results suggest that VP→VTA activity is more important for reinforcement than for invigoration of reward seeking by cues.
Collapse
Affiliation(s)
- Dakota Palmer
- Graduate Program in Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA; Medical Discovery Team on Addiction, University of Minnesota, Minneapolis, MN 55455, USA
| | - Christelle A Cayton
- Medical Discovery Team on Addiction, University of Minnesota, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Alexandra Scott
- Medical Discovery Team on Addiction, University of Minnesota, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Iris Lin
- Medical Discovery Team on Addiction, University of Minnesota, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Bailey Newell
- Medical Discovery Team on Addiction, University of Minnesota, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Anika Paulson
- Medical Discovery Team on Addiction, University of Minnesota, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Morgan Weberg
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jocelyn M Richard
- Medical Discovery Team on Addiction, University of Minnesota, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
6
|
Ihara K, Shikano Y, Kato S, Yagishita S, Tanaka KF, Takata N. A reinforcement learning model with choice traces for a progressive ratio schedule. Front Behav Neurosci 2024; 17:1302842. [PMID: 38268795 PMCID: PMC10806202 DOI: 10.3389/fnbeh.2023.1302842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 12/13/2023] [Indexed: 01/26/2024] Open
Abstract
The progressive ratio (PR) lever-press task serves as a benchmark for assessing goal-oriented motivation. However, a well-recognized limitation of the PR task is that only a single data point, known as the breakpoint, is obtained from an entire session as a barometer of motivation. Because the breakpoint is defined as the final ratio of responses achieved in a PR session, variations in choice behavior during the PR task cannot be captured. We addressed this limitation by constructing four reinforcement learning models: a simple Q-learning model, an asymmetric model with two learning rates, a perseverance model with choice traces, and a perseverance model without learning. These models incorporated three behavioral choices: reinforced and non-reinforced lever presses and void magazine nosepokes, because we noticed that male mice performed frequent magazine nosepokes during PR tasks. The best model was the perseverance model, which predicted a gradual reduction in amplitudes of reward prediction errors (RPEs) upon void magazine nosepokes. We confirmed the prediction experimentally with fiber photometry of extracellular dopamine (DA) dynamics in the ventral striatum of male mice using a fluorescent protein (genetically encoded GPCR activation-based DA sensor: GRABDA2m). We verified application of the model by acute intraperitoneal injection of low-dose methamphetamine (METH) before a PR task, which increased the frequency of magazine nosepokes during the PR session without changing the breakpoint. The perseverance model captured behavioral modulation as a result of increased initial action values, which are customarily set to zero and disregarded in reinforcement learning analysis. Our findings suggest that the perseverance model reveals the effects of psychoactive drugs on choice behaviors during PR tasks.
Collapse
Affiliation(s)
- Keiko Ihara
- Division of Brain Sciences, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
| | - Yu Shikano
- Division of Brain Sciences, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
- Department of Biology, Stanford University, Stanford, CA, United States
| | - Sae Kato
- Division of Brain Sciences, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
| | - Sho Yagishita
- Center for Disease Biology and Integrative Medicine, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kenji F. Tanaka
- Division of Brain Sciences, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
| | - Norio Takata
- Division of Brain Sciences, Institute for Advanced Medical Research, Keio University School of Medicine, Tokyo, Japan
| |
Collapse
|
7
|
Kim K, Picciotto MR. Nicotine addiction: More than just dopamine. Curr Opin Neurobiol 2023; 83:102797. [PMID: 37832393 PMCID: PMC10842238 DOI: 10.1016/j.conb.2023.102797] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 10/15/2023]
Abstract
Despite decades of research and anti-tobacco messaging, nicotine addiction remains an important public health problem leading to hundreds of thousands of deaths each year. While fundamental studies have identified molecular, circuit-level and behavioral mechanisms important for nicotine reinforcement and withdrawal, recent studies have identified additional pathways that are important for both nicotine seeking and aversion. In particular, although dopaminergic mechanisms are necessary for nicotine-dependent reward and drug-seeking, novel glutamate and GABA signaling mechanisms in the mesolimbic system have been identified for their contributions to reward-related behaviors. An additional area of active investigation for nicotine addiction focuses on molecular mechanisms in the habenula-interpeduncular pathway driving nicotine aversion and withdrawal. Across all these domains, sex differences in the molecular basis of nicotine-induced behaviors have emerged that identify important new directions for future research. Recent studies reviewed here highlight additional pathways that could provide therapeutic targets for smoking cessation and problematic nicotine vaping.
Collapse
Affiliation(s)
- Kristen Kim
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06508, USA; Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA. https://twitter.com/kristenkim415
| | - Marina R Picciotto
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06508, USA; Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06508, USA.
| |
Collapse
|
8
|
Dalléry R, Saleh Y, Manohar S, Husain M. Persistence of effort in apathy. Rev Neurol (Paris) 2023; 179:1047-1060. [PMID: 37451928 DOI: 10.1016/j.neurol.2023.03.017] [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: 12/19/2021] [Revised: 02/19/2023] [Accepted: 03/29/2023] [Indexed: 07/18/2023]
Abstract
The syndrome of apathy has generated increasing interest in recent years as systematic evaluations have revealed its high prevalence and strong negative impact on quality of life across a wide range of neurological and psychiatric conditions. However, although several theoretical models have been proposed to account for various aspects of the condition, understanding of this syndrome is still incomplete. One influential model has proposed that apathy might be described as a quantitative reduction of goal-directed behaviour in comparison to an individual's prior level of functioning. Persistence of activity defined as the capacity to continue with a task - sometimes in the face of setbacks, high levels of difficulty or fatigue - is a crucial but understudied aspect of goal-directed behaviour. Surprisingly, it has not been investigated yet in the context of apathy. Here, we provide an overview of theoretical and experimental aspects of persistence in effort that might assist to develop methods for the investigation of persistence in human behaviour, particularly within the pathologic context of apathy.
Collapse
Affiliation(s)
- R Dalléry
- Department of Experimental Psychology, University of Oxford, Oxford, UK; Université Paris Sorbonne, Paris, France; Service de neurologie, centre de référence maladie de Huntington, hôpital Henri-Mondor-Albert-Chenevier, AP-HP, 94010 Créteil, France.
| | - Y Saleh
- Department of Experimental Psychology, University of Oxford, Oxford, UK; Nuffield Department Clinical Neurosciences, University of Oxford, Oxford, UK
| | - S Manohar
- Department of Experimental Psychology, University of Oxford, Oxford, UK; Institute of Cognitive Neuroscience, University College London, London, UK
| | - M Husain
- Department of Experimental Psychology, University of Oxford, Oxford, UK; Nuffield Department Clinical Neurosciences, University of Oxford, Oxford, UK
| |
Collapse
|
9
|
Wallace ML, Sabatini BL. Synaptic and circuit functions of multitransmitter neurons in the mammalian brain. Neuron 2023; 111:2969-2983. [PMID: 37463580 PMCID: PMC10592565 DOI: 10.1016/j.neuron.2023.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/31/2023] [Accepted: 06/08/2023] [Indexed: 07/20/2023]
Abstract
Neurons in the mammalian brain are not limited to releasing a single neurotransmitter but often release multiple neurotransmitters onto postsynaptic cells. Here, we review recent findings of multitransmitter neurons found throughout the mammalian central nervous system. We highlight recent technological innovations that have made the identification of new multitransmitter neurons and the study of their synaptic properties possible. We also focus on mechanisms and molecular constituents required for neurotransmitter corelease at the axon terminal and synaptic vesicle, as well as some possible functions of multitransmitter neurons in diverse brain circuits. We expect that these approaches will lead to new insights into the mechanism and function of multitransmitter neurons, their role in circuits, and their contribution to normal and pathological brain function.
Collapse
Affiliation(s)
- Michael L Wallace
- Department of Anatomy and Neurobiology, Boston University Chobanian & Avedisian School of Medicine, Boston, MA, USA.
| | - Bernardo L Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
10
|
Bouarab C, Wynalda M, Thompson BV, Khurana A, Cody CR, Kisner A, Polter AM. Sex-specific adaptations to VTA circuits following subchronic stress. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.02.551665. [PMID: 37577542 PMCID: PMC10418168 DOI: 10.1101/2023.08.02.551665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Dysregulation of the mesolimbic reward circuitry is implicated in the pathophysiology of stress-related illnesses such as depression and anxiety. These disorders are more frequently diagnosed in females, and sex differences in the response to stress are likely to be one factor that leads to enhanced vulnerability of females. In this study, we use subchronic variable stress (SCVS), a model in which females are uniquely vulnerable to behavioral disturbances, to investigate sexually divergent mechanisms of regulation of the ventral tegmental area by stress. Using slice electrophysiology, we find that female, but not male mice have a reduction in the ex vivo firing rate of VTA dopaminergic neurons following SCVS. Surprisingly, both male and female animals show an increase in inhibitory tone onto VTA dopaminergic neurons and an increase in the firing rate of VTA GABAergic neurons. In males, however, this is accompanied by a robust increase in excitatory synaptic tone onto VTA dopamine neurons. This supports a model by which SCVS recruits VTA GABA neurons to inhibit dopaminergic neurons in both male and female mice, but males are protected from diminished functioning of the dopaminergic system by a compensatory upregulation of excitatory synapses.
Collapse
Affiliation(s)
- Chloé Bouarab
- Department of Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037
- Current address: Institut Pasteur, 25-28 rue du Docteur Roux, 75015 Paris
| | - Megan Wynalda
- Department of Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037
| | - Brittney V. Thompson
- Department of Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037
- Current address: Department of Psychology, Florida State University, Tallahasse, FL, 32306
| | - Ambika Khurana
- Department of Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037
| | - Caitlyn R. Cody
- Department of Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037
- Current address: Department of Psychology, Northeastern University, Boston, MA, 02115
| | - Alexandre Kisner
- Department of Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037
- Current address: Department of Neuroscience, American University, Washington DC 20016
| | - Abigail M. Polter
- Department of Pharmacology and Physiology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037
| |
Collapse
|
11
|
Faget L, Oriol L, Lee WC, Sargent C, Ramanathan D, Hnasko TS. Ventral pallidum GABA and glutamate neurons drive approach and avoidance through distinct modulation of VTA cell types. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.12.548750. [PMID: 37502884 PMCID: PMC10369949 DOI: 10.1101/2023.07.12.548750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
The ventral pallidum (VP) contains GABA and glutamate (Glut) neurons projecting to ventral tegmental area (VTA) whose stimulation drives approach and avoidance, respectively. Yet little is known about the cell-type-specific mechanisms by which VP projections to VTA drive behavior. Here, we found that both VP GABA and Glut neurons were activated during approach to reward or delivery of an aversive stimulus. Stimulation of VP GABA neurons inhibited VTA GABA, but activated dopamine (DA) and glutamate neurons. Remarkably, this cell-type-specific recruitment was behavior-contingent such that VTA recruitment was inhibited when evoked by the subject's own action. Conversely, VP Glut neurons activated VTA GABA, as well as DA and Glut neurons, despite driving aversion. However, VP Glut neurons evoked DA in reward-associated ventromedial nucleus accumbens (NAc), but reduced DA in aversion-associated dorsomedial NAc. These findings show how heterogeneous VP cell types can engage VTA cell types to shape approach and avoidance behaviors.
Collapse
Affiliation(s)
- Lauren Faget
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA
| | - Lucie Oriol
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Wen-Chun Lee
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Cody Sargent
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Dhakshin Ramanathan
- Department of Psychiatry, University of California, San Diego, La Jolla, CA 92093, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA
| | - Thomas S. Hnasko
- Department of Neurosciences, University of California San Diego, La Jolla, CA 92093, USA
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA 92161, USA
| |
Collapse
|
12
|
Tang H, Zhang Y, Xun Y, Yu J, Lu Y, Zhang R, Dang W, Zhu F, Zhang J. Association between methylation in the promoter region of the GAD2 gene and opioid use disorder. Brain Res 2023; 1812:148407. [PMID: 37182687 DOI: 10.1016/j.brainres.2023.148407] [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: 01/17/2023] [Revised: 04/26/2023] [Accepted: 05/09/2023] [Indexed: 05/16/2023]
Abstract
DNA methylation is one of the epigenetic mechanisms involved in opioid use disorder. GAD2 is a key catalyticase in gamma amino butyric acid (GABA) synthesis from glutamate, that is implicated in opioid-induced rewarding effect. To reveal the relationship and the underlying mechanism between GAD2 gene methylation and opioid use disorder, we first examined and compared the methylation levels in the promoter region of the GAD2 gene in peripheral blood between 120 patients with opioid use disorder and 110 healthy controls by using a targeted approach. A diagnostic model with methylation biomarkers was established to distinguish opioid use disorder and healthy control groups. Correlations between methylation levels in the promoter region of the GAD2 gene and the duration and dosage of opioid use were then determined. Finally, the transcription factors that potentially bind to the target sequences including the detected CpG sites were predicted with the JASPAR database. Our results demonstrated that hypermethylation in the promoter region of the GAD2 gene was associated with opioid use disorder. A diagnostic model based on 10 methylation biomarkers could distinguish the opioid use disorder and healthy control groups. Several correlations between methylation levels in the GAD2 gene promoter and the duration and dosage of opioid use were observed. Transcription factors TFAP2A, Arnt and Runx1 were predicted to bind to the target sequences including several CpG sites detected in the present study in the GAD2 gene promoter. Our findings highlight and extend the role of DNA methylation in the GAD2 gene in opioid use disorder.
Collapse
Affiliation(s)
- Hua Tang
- Healthy Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China; Xi'an International Medical Center Hospital, Xi'an, Shaanxi 710061, China
| | - Yudan Zhang
- Healthy Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China; Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Yufeng Xun
- Healthy Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China; Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Jiao Yu
- Healthy Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Ye Lu
- Healthy Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China; Key Laboratory of National Health Commission for Forensic Science, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Rui Zhang
- Department of Psychiatry, Xi'an Mental Health Center, Xi'an, Shaanxi 710061, China
| | - Wei Dang
- Department of Psychiatry, Xi'an Mental Health Center, Xi'an, Shaanxi 710061, China
| | - Feng Zhu
- Healthy Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China; Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China
| | - Jianbo Zhang
- Healthy Science Center, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China; Key Laboratory of National Health Commission for Forensic Science, Xi'an Jiaotong University, Xi'an, Shaanxi 710061, China.
| |
Collapse
|
13
|
Akmese C, Sevinc C, Halim S, Unal G. Differential role of GABAergic and cholinergic ventral pallidal neurons in behavioral despair, conditioned fear memory and active coping. Prog Neuropsychopharmacol Biol Psychiatry 2023; 125:110760. [PMID: 37031946 DOI: 10.1016/j.pnpbp.2023.110760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/24/2023] [Accepted: 04/06/2023] [Indexed: 04/11/2023]
Abstract
The ventral pallidum (VP), a major component of the reward circuit, is well-associated with appetitive behaviors. Recent evidence suggests that this basal forebrain nucleus may have an overarching role in affective processing, including behavioral responses to aversive stimuli. We investigated this by utilizing selective immunotoxin lesions and a series of behavioral tests in adult male Wistar rats. We made bilateral GAT1-Saporin, 192-IgG-Saporin or PBS (vehicle) injections into the VP to respectively eliminate GABAergic and cholinergic neurons, and tested the animals in the forced swim test (FST), open field test (OFT), elevated plus maze (EPM), Morris water maze (MWM) and cued fear conditioning. Both GAT1-Saporin and 192-IgG-Saporin injections reduced behavioral despair without altering general locomotor activity. During the acquisition phase of cued fear conditioning, this antidepressant effect was accompanied by reduced freezing and increased darting in the 192-IgG-Saporin group, and increased jumping in the GAT1-Saporin group. In the extinction phase, cholinergic lesions impaired fear memory irrespective of the context, while GABAergic lesions reduced memory durability only during the early phases of extinction in a novel context. In line with this, selective cholinergic, but not GABAergic, lesions impaired spatial memory in the MWM. We observed no consistent effect in anxiety-like behavior assessed in the OFT and EPM. These findings indicate that both the GABAergic and cholinergic neuronal groups of the VP may contribute to emotion regulation through modulation of behavioral despair and acquired fear by suppressing active coping and promoting species-specific passive behaviors.
Collapse
Affiliation(s)
- Cemal Akmese
- Behavioral Neuroscience Laboratory, Department of Psychology, Boğaziçi University, 34342 Istanbul, Turkey
| | - Cem Sevinc
- Behavioral Neuroscience Laboratory, Department of Psychology, Boğaziçi University, 34342 Istanbul, Turkey
| | - Sahar Halim
- Behavioral Neuroscience Laboratory, Department of Psychology, Boğaziçi University, 34342 Istanbul, Turkey
| | - Gunes Unal
- Behavioral Neuroscience Laboratory, Department of Psychology, Boğaziçi University, 34342 Istanbul, Turkey.
| |
Collapse
|
14
|
Creed MC, Loureiro M, Lüscher C. Invariant inhibition to calculate prediction errors? Trends Neurosci 2023; 46:257-259. [PMID: 36707259 DOI: 10.1016/j.tins.2023.01.004] [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: 12/02/2022] [Accepted: 01/15/2023] [Indexed: 01/27/2023]
Abstract
The ventral tegmental area (VTA) has a pivotal role in motivated behavior. Much of the research on the VTA has focused on the mesocorticolimbic dopamine projections and their role in the computation of a 'reward prediction error' (RPE) for reward-guided learning. In a recent study, Zhou et al. report that VTA GABA neurons, the axons of which innervate the ventral pallidum (VP), have a unique role in signaling reward value to the basal ganglia and guiding reward seeking.
Collapse
Affiliation(s)
- Meaghan C Creed
- Department of Anesthesiology, Washington University in St Louis, St Louis, MO, USA; Department of Psychiatry, Washington University in St Louis, St Louis, MO, USA; Department of Neuroscience, Washington University in St Louis, St Louis, MO, USA; Department of Biomedical Engineering, Washington University in St Louis, St Louis, MO, USA; Pain Center, Washington University in St Louis, St Louis, MO, USA
| | - Michaël Loureiro
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, CH-1211 Geneva, Switzerland
| | - Christian Lüscher
- Department of Basic Neurosciences, Medical Faculty, University of Geneva, CH-1211 Geneva, Switzerland; Clinic of Neurology, Department of Clinical Neurosciences, Geneva University Hospital, CH-1211 Geneva, Switzerland.
| |
Collapse
|
15
|
Soares-Cunha C, Heinsbroek JA. Ventral pallidal regulation of motivated behaviors and reinforcement. Front Neural Circuits 2023; 17:1086053. [PMID: 36817646 PMCID: PMC9932340 DOI: 10.3389/fncir.2023.1086053] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 01/06/2023] [Indexed: 02/05/2023] Open
Abstract
The interconnected nuclei of the ventral basal ganglia have long been identified as key regulators of motivated behavior, and dysfunction of this circuit is strongly implicated in mood and substance use disorders. The ventral pallidum (VP) is a central node of the ventral basal ganglia, and recent studies have revealed complex VP cellular heterogeneity and cell- and circuit-specific regulation of reward, aversion, motivation, and drug-seeking behaviors. Although the VP is canonically considered a relay and output structure for this circuit, emerging data indicate that the VP is a central hub in an extensive network for reward processing and the regulation of motivation that extends beyond classically defined basal ganglia borders. VP neurons respond temporally faster and show more advanced reward coding and prediction error processing than neurons in the upstream nucleus accumbens, and regulate the activity of the ventral mesencephalon dopamine system. This review will summarize recent findings in the literature and provide an update on the complex cellular heterogeneity and cell- and circuit-specific regulation of motivated behaviors and reinforcement by the VP with a specific focus on mood and substance use disorders. In addition, we will discuss mechanisms by which stress and drug exposure alter the functioning of the VP and produce susceptibility to neuropsychiatric disorders. Lastly, we will outline unanswered questions and identify future directions for studies necessary to further clarify the central role of VP neurons in the regulation of motivated behaviors. Significance: Research in the last decade has revealed a complex cell- and circuit-specific role for the VP in reward processing and the regulation of motivated behaviors. Novel insights obtained using cell- and circuit-specific interrogation strategies have led to a major shift in our understanding of this region. Here, we provide a comprehensive review of the VP in which we integrate novel findings with the existing literature and highlight the emerging role of the VP as a linchpin of the neural systems that regulate motivation, reward, and aversion. In addition, we discuss the dysfunction of the VP in animal models of neuropsychiatric disorders.
Collapse
Affiliation(s)
- Carina Soares-Cunha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Jasper A. Heinsbroek
- Department of Anesthesiology, University of Colorado, Anschutz Medical Campus, Aurora, CO, United States
| |
Collapse
|
16
|
Ostlund I, Von Gunten M, Smith C, Edwards JG. Chronic Δ9-tetrahydrocannabinol impact on plasticity, and differential activation requirement for CB1-dependent long-term depression in ventral tegmental area GABA neurons in adult versus young mice. Front Neurosci 2023; 16:1067493. [PMID: 36699526 PMCID: PMC9869137 DOI: 10.3389/fnins.2022.1067493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 12/12/2022] [Indexed: 01/11/2023] Open
Abstract
The ventral tegmental area (VTA) mediates incentive salience and reward prediction error through dopamine (DA) neurons that are regulated by local VTA GABA neurons. In young mice, VTA GABA cells exhibit a form of synaptic plasticity known as long-term depression (LTD) that is dependent on cannabinoid 1 (CB1) receptors preceded by metabotropic glutamate receptor 5 (mGluR5) signaling to induce endocannabinoid production. This LTD was eliminated following chronic (7-10 consecutive days) exposure to the marijuana derived cannabinoid Δ9 -tetrahydrocannabinol (THC). We now examine the mechanism behind THC-induced elimination of LTD in adolescents as well as plasticity induction ability in adult versus young male and female mice using whole-cell electrophysiology experiments of VTA GABA cells. Chronic THC injections in adolescents resulted in a loss of CB1 agonist-mediated depression, illustrating chronic THC likely desensitizes or removes synaptic CB1. We noted that seven days withdrawal from chronic THC restored LTD and CB1 agonist-induced depression, suggesting reversibility of THC-induced changes. Adult mice continue to express functional mGluR5 and CB1, but require a doubling of the synaptic stimulation compared to young mice to induce LTD, suggesting a quantitative difference in CB1-dependent plasticity between young and adult mice. One potential rationale for this difference is changes in AMPA and NMDA glutamate receptors. Indeed, AMPA/NMDA ratios were increased in in adults compared to young mice. Lastly, we performed quantitative reverse-transcription PCR and identified that CB1, DAGLα, and GluA1 levels increased following chronic THC exposure. Collectively, our data demonstrate the first age-dependent GABA neuron plasticity in the VTA, which could have implications for decreased THC dependence capacity in adults, as well as the mechanism behind chronic THC-induced synaptic alterations in young mice.
Collapse
Affiliation(s)
- Isaac Ostlund
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT, United States
| | | | - Calvin Smith
- Neuroscience Center, Brigham Young University, Provo, UT, United States
| | - Jeffrey G. Edwards
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT, United States
- Neuroscience Center, Brigham Young University, Provo, UT, United States
| |
Collapse
|