51
|
Animal models of fatigue in major depressive disorder. Physiol Behav 2018; 199:300-305. [PMID: 30513290 DOI: 10.1016/j.physbeh.2018.11.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/29/2018] [Accepted: 11/30/2018] [Indexed: 02/08/2023]
Abstract
Fatigue is common in a host of neurological and psychiatric disorders including depression and often continues unabated even after primary symptoms of disease are treated. Its high estimated prevalence combined with the lack of effective medicines has engaged the preclinical research community to search for fatigue models. The present review briefly summarizes the most common animal models that have been brought forward along with some of the associated pharmacological validation data. Like all preclinical models, these models have issues that need to be appreciated in the generation and interpretation of data for the purposes of translation to human disease; specifically, there are deficiencies in construct validity, a lack of medicines that effectively address residual fatigue symptoms, and difficulties in defining specificity with respect to drug effects on fatigue per se. Nonetheless, existing animal models of fatigue arguably serve the valuable purpose of encouraging research in this large area of unmet medical need. Data from these models are predicted to engender human experimentation and the further development of improved model systems.
Collapse
|
52
|
Scheggi S, De Montis MG, Gambarana C. Making Sense of Rodent Models of Anhedonia. Int J Neuropsychopharmacol 2018; 21:1049-1065. [PMID: 30239762 PMCID: PMC6209858 DOI: 10.1093/ijnp/pyy083] [Citation(s) in RCA: 118] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 09/18/2018] [Indexed: 01/04/2023] Open
Abstract
A markedly reduced interest or pleasure in activities previously considered pleasurable is a main symptom in mood disorder and psychosis and is often present in other psychiatric disorders and neurodegenerative diseases. This condition can be labeled as "anhedonia," although in its most rigorous connotation the term refers to the lost capacity to feel pleasure that is one aspect of the complex phenomenon of processing and responding to reward. The responses to rewarding stimuli are relatively easy to study in rodents, and the experimental conditions that consistently and persistently impair these responses are used to model anhedonia. To this end, long-term exposure to environmental aversive conditions is primarily used, and the resulting deficits in reward responses are often accompanied by other deficits that are mainly reminiscent of clinical depressive symptoms. The different components of impaired reward responses induced by environmental aversive events can be assessed by different tests or protocols that require different degrees of time allocation, technical resources, and equipment. Rodent models of anhedonia are valuable tools in the study of the neurobiological mechanisms underpinning impaired behavioral responses and in the screening and characterization of drugs that may reverse these behavioral deficits. In particular, the antianhedonic or promotivational effects are relevant features in the spectrum of activities of drugs used in mood disorders or psychosis. Thus, more than the model, it is the choice of tests that is crucial since it influences which facets of anhedonia will be detected and should be tuned to the purpose of the study.
Collapse
Affiliation(s)
- Simona Scheggi
- Department of Molecular and Developmental Medicine, University of Siena
| | | | - Carla Gambarana
- Department of Molecular and Developmental Medicine, University of Siena,Correspondence: Carla Gambarana, Department of Molecular and Developmental Medicine, University of Siena, Via Aldo Moro, 2 – 53100 Siena, Italy ()
| |
Collapse
|
53
|
Neurobiology and pharmacology of activational and effort-related aspects of motivation: rodent studies. Curr Opin Behav Sci 2018. [DOI: 10.1016/j.cobeha.2018.01.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
54
|
Abstract
Loss of interest in rewarding activities is a hallmark of many psychiatric disorders and may be relevant for neurodegenerative disorders and patients suffering from brain injury. There is increasing evidence that deficits in reward-related behaviour are more complex than previously described. The traditional view of anhedonia as 'the inability to experience pleasure' may be too limited to fully encompass the types of reward deficit observed in these patients. Developments in methods to measure different aspects of reward processing in humans and animals are starting to provide insights into the complexity of this behaviour. In this article we consider the rodent models which have traditionally been used to study reward deficits in psychiatric disorders and consider their limitations relative to clinical findings. We then discuss work where methods derived from human neuropsychological tests are providing insights into the complexity of reward-related behaviour. Specifically, we consider tasks which investigate different aspects of reward-related behaviour focusing on learning and memory as well as decision-making and consider what these may mean in terms of how we model reward deficits in rodents.
Collapse
Affiliation(s)
- Chloe L Slaney
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University Walk, Bristol BS8 4PX, UK
| | - Claire A Hales
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University Walk, Bristol BS8 4PX, UK
| | - Emma S J Robinson
- School of Physiology, Pharmacology & Neuroscience, Biomedical Sciences Building, University Walk, Bristol BS8 4PX, UK
| |
Collapse
|
55
|
Persistent effect of withdrawal from intravenous methamphetamine self-administration on brain activation and behavioral economic indices involving an effort cost. Neuropharmacology 2018; 140:130-138. [PMID: 30053443 DOI: 10.1016/j.neuropharm.2018.07.023] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 06/14/2018] [Accepted: 07/22/2018] [Indexed: 11/24/2022]
Abstract
Exposure to drugs of abuse produces maladaptive changes in cost-benefit decision-making, including the evaluation of time and risk. Studies probing the effects of drug exposure on such evaluations have primarily used experimenter-administered drug regimens. Similarly, while much is known about the neural bases of effort, there have been relatively fewer investigations of the effects of drug experience on effort-based choices. We recently reported that experimenter-administered methamphetamine (meth) resulted in steeper discounting of effort for food rewards in rats, when assessed in protracted withdrawal. Here, we studied rats that underwent withdrawal from weeks of meth intravenous self-administration that later could freely select between a high effort, preferred option (progressive ratio lever pressing for sucrose pellets) versus a low effort, less preferred option (freely-available lab chow). We found decreased effort for the preferred reward and changes in a behavioral economic index demonstrating an increased sensitivity to effort in meth-experienced rats. Critically, the decreased effort for the preferred option was only present in the context of a competing option, not when it was the only option. We also confirmed rats preferred sucrose pellets over chow when both were freely available. These long-lasting changes were accompanied by decreased c-Fos activation in ventral striatum and basolateral amygdala, regions known to be important in effort-based choices. Taken together with our previous observations, these results suggest a robust and enduring effect of meth on value-based decision-making, and point to the underlying neural mechanisms that support the evaluation of an effort cost.
Collapse
|
56
|
López-Cruz L, San Miguel N, Carratalá-Ros C, Monferrer L, Salamone JD, Correa M. Dopamine depletion shifts behavior from activity based reinforcers to more sedentary ones and adenosine receptor antagonism reverses that shift: Relation to ventral striatum DARPP32 phosphorylation patterns. Neuropharmacology 2018; 138:349-359. [PMID: 29408363 DOI: 10.1016/j.neuropharm.2018.01.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 01/18/2018] [Accepted: 01/24/2018] [Indexed: 01/18/2023]
Abstract
The mesolimbic dopamine (DA) system plays a critical role in behavioral activation and effort-based decision-making. DA depletion produces anergia (shifts to low effort options) in animals tested on effort-based decision-making tasks. Caffeine, the most consumed stimulant in the world, acts as an adenosine A1/A2A receptor antagonist, and in striatal areas DA D1 and D2 receptors are co-localized with adenosine A1 and A2A receptors respectively. In the present work, we evaluated the effect of caffeine on anergia induced by the VMAT-2 inhibitor tetrabenazine (TBZ), which depletes DA. Anergia was evaluated in a three-chamber T-maze task in which animals can chose between running on a wheel (RW) vs. sedentary activities such as consuming sucrose or sniffing a neutral odor. TBZ-caffeine interactions in ventral striatum were evaluated using DARPP-32 phosphorylation patterns as an intracellular marker of DA-adenosine receptor interaction. In the T-maze, control mice spent more time running and much less consuming sucrose or sniffing. TBZ (4.0 mg/kg) reduced ventral striatal DA tissue levels as measured by HPLC, and also shifted preferences in the T-maze, reducing selection of the reinforcer that involved vigorous activity (RW), but increasing consumption of a reinforcer that required little effort (sucrose), at doses that had no effect on independent measures of appetite or locomotion in a RW. Caffeine at doses that had no effect on their own reversed the effects of TBZ on T-maze performance, and also suppressed TBZ-induced pDARPP-32(Thr34) expression as measured by western blot, suggesting a role for D2-A2A interactions. These results support the idea that DA depletion produces anergia, but does not affect the primary motivational effects of sucrose. Caffeine, possibly by acting on A2A receptors in ventral striatum, reversed the DA depletion effects. It is possible that caffeine, like selective adenosine A2A antagonists, could have some therapeutic benefit for treating effort-related symptoms.
Collapse
Affiliation(s)
- Laura López-Cruz
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain
| | - Noemí San Miguel
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain
| | - Carla Carratalá-Ros
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain
| | - Lidón Monferrer
- Àrea de Didàctica Ciències Experimentals, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain
| | - John D Salamone
- Behavioral Neuroscience Div., University of Connecticut, Storrs, 06269-1020 CT, USA
| | - Mercè Correa
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain; Behavioral Neuroscience Div., University of Connecticut, Storrs, 06269-1020 CT, USA.
| |
Collapse
|
57
|
Bogatko K, Poleszak E, Szopa A, Wyska E, Wlaź P, Świąder K, Wlaź A, Doboszewska U, Rojek K, Serefko A. The influence of selective A1 and A2A receptor antagonists on the antidepressant-like activity of moclobemide, venlafaxine and bupropion in mice. J Pharm Pharmacol 2018; 70:1200-1208. [DOI: 10.1111/jphp.12954] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 05/28/2018] [Indexed: 11/28/2022]
Abstract
Abstract
Objective
The main goal of our study was to investigate whether a selective antagonism of the adenosine A1 or A2A receptors is able to enhance the antidepressant activity of commonly prescribed drugs.
Materials and methods
All experiments were carried out on male Albino Swiss mice. The forced swim test and the tail suspension test were used to evaluate the antidepressant-like potential. Drug concentrations in animals’ serum and brains were measured by high-performance liquid chromatography.
Key findings
The antidepressant potential of moclobemide (1.5 mg/kg), venlafaxine (1 mg/kg) and bupropion (10 mg/kg) was enhanced by a co-administration with 3,7-dimethyl-1-propargylxanthine (DMPX; an antagonist of adenosine A2A receptors; 3 mg/kg) or 8-cyclopentyl-1,3-dipropylxanthine (an antagonist of adenosine A1 receptors; 1 mg/kg). However, significant interactions between the tested substances were detected only in the experiments with DMPX. The nature of the observed interplays is rather pharmacodynamic than pharmacokinetic, because neither serum nor brain concentrations of the used drugs were significantly increased.
Conclusions
Blockage of the adenosine receptors (particularly the A2A subtypes) could be considered in future as a novel, promising part of the combined antidepressant therapy. However, further studies on this subject are needed.
Collapse
Affiliation(s)
- Karolina Bogatko
- Department of Applied Pharmacy, Medical University of Lublin, Lublin, Poland
| | - Ewa Poleszak
- Department of Applied Pharmacy, Medical University of Lublin, Lublin, Poland
| | - Aleksandra Szopa
- Department of Applied Pharmacy, Medical University of Lublin, Lublin, Poland
| | - Elżbieta Wyska
- Department of Pharmacokinetics and Physical Pharmacy, Collegium Medicum, Jagiellonian University, Kraków, Poland
| | - Piotr Wlaź
- Department of Animal Physiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Lublin, Poland
| | - Katarzyna Świąder
- Department of Applied Pharmacy, Medical University of Lublin, Lublin, Poland
| | - Aleksandra Wlaź
- Department of Pathophysiology, Medical University of Lublin, Lublin, Poland
| | - Urszula Doboszewska
- Department of Animal Physiology, Faculty of Biology and Biotechnology, Maria Curie-Skłodowska University, Lublin, Poland
| | - Karol Rojek
- Department of Applied Pharmacy, Medical University of Lublin, Lublin, Poland
| | - Anna Serefko
- Department of Applied Pharmacy, Medical University of Lublin, Lublin, Poland
| |
Collapse
|
58
|
López-Cruz L, Salamone JD, Correa M. Caffeine and Selective Adenosine Receptor Antagonists as New Therapeutic Tools for the Motivational Symptoms of Depression. Front Pharmacol 2018; 9:526. [PMID: 29910727 PMCID: PMC5992708 DOI: 10.3389/fphar.2018.00526] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 05/01/2018] [Indexed: 01/06/2023] Open
Abstract
Major depressive disorder is one of the most common and debilitating psychiatric disorders. Some of the motivational symptoms of depression, such anergia (lack of self-reported energy) and fatigue are relatively resistant to traditional treatments such as serotonin uptake inhibitors. Thus, new pharmacological targets are being investigated. Epidemiological data suggest that caffeine consumption can have an impact on aspects of depressive symptomatology. Caffeine is a non-selective adenosine antagonist for A1/A2A receptors, and has been demonstrated to modulate behavior in classical animal models of depression. Moreover, selective adenosine receptor antagonists are being assessed for their antidepressant effects in animal studies. This review focuses on how caffeine and selective adenosine antagonists can improve different aspects of depression in humans, as well as in animal models. The effects on motivational symptoms of depression such as anergia, fatigue, and psychomotor slowing receive particular attention. Thus, the ability of adenosine receptor antagonists to reverse the anergia induced by dopamine antagonism or depletion is of special interest. In conclusion, although further studies are needed, it appears that caffeine and selective adenosine receptor antagonists could be therapeutic agents for the treatment of motivational dysfunction in depression.
Collapse
Affiliation(s)
- Laura López-Cruz
- Àrea de Psicobiologia, Universitat Jaume I, Castellón de la Plana, Spain
| | - John D. Salamone
- Behavioral Neuroscience Division, University of Connecticut, Storrs, CT, United States
| | - Mercè Correa
- Àrea de Psicobiologia, Universitat Jaume I, Castellón de la Plana, Spain
- Behavioral Neuroscience Division, University of Connecticut, Storrs, CT, United States
| |
Collapse
|
59
|
The monoamine-oxidase B inhibitor deprenyl increases selection of high-effort activity in rats tested on a progressive ratio/chow feeding choice procedure: Implications for treating motivational dysfunctions. Behav Brain Res 2018; 342:27-34. [DOI: 10.1016/j.bbr.2017.12.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 12/12/2017] [Accepted: 12/28/2017] [Indexed: 01/14/2023]
|
60
|
Salamone JD, Correa M, Yang JH, Rotolo R, Presby R. Dopamine, Effort-Based Choice, and Behavioral Economics: Basic and Translational Research. Front Behav Neurosci 2018; 12:52. [PMID: 29628879 PMCID: PMC5876251 DOI: 10.3389/fnbeh.2018.00052] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 02/28/2018] [Indexed: 01/14/2023] Open
Abstract
Operant behavior is not only regulated by factors related to the quality or quantity of reinforcement, but also by the work requirements inherent in performing instrumental actions. Moreover, organisms often make effort-related decisions involving economic choices such as cost/benefit analyses. Effort-based decision making is studied using behavioral procedures that offer choices between high-effort options leading to relatively preferred reinforcers vs. low effort/low reward choices. Several neural systems, including the mesolimbic dopamine (DA) system and other brain circuits, are involved in regulating effort-related aspects of motivation. Considerable evidence indicates that mesolimbic DA transmission exerts a bi-directional control over exertion of effort on instrumental behavior tasks. Interference with DA transmission produces a low-effort bias in animals tested on effort-based choice tasks, while increasing DA transmission with drugs such as DA transport blockers tends to enhance selection of high-effort options. The results from these pharmacology studies are corroborated by the findings from recent articles using optogenetic, chemogenetic and physiological techniques. In addition to providing important information about the neural regulation of motivated behavior, effort-based choice tasks are useful for developing animal models of some of the motivational symptoms that are seen in people with various psychiatric and neurological disorders (e.g., depression, schizophrenia, Parkinson’s disease). Studies of effort-based decision making may ultimately contribute to the development of novel drug treatments for motivational dysfunction.
Collapse
Affiliation(s)
- John D Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Merce Correa
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States.,Area de Psicobiologia, Universitat de Jaume I, Castelló, Spain
| | - Jen-Hau Yang
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Renee Rotolo
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Rose Presby
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| |
Collapse
|
61
|
Contreras-Mora H, Rowland MA, Yohn SE, Correa M, Salamone JD. Partial reversal of the effort-related motivational effects of tetrabenazine with the MAO-B inhibitor deprenyl (selegiline): Implications for treating motivational dysfunctions. Pharmacol Biochem Behav 2018; 166:13-20. [DOI: 10.1016/j.pbb.2018.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 12/29/2017] [Accepted: 01/04/2018] [Indexed: 12/30/2022]
|
62
|
Correa M, SanMiguel N, López-Cruz L, Carratalá-Ros C, Olivares-García R, Salamone JD. Caffeine Modulates Food Intake Depending on the Context That Gives Access to Food: Comparison With Dopamine Depletion. Front Psychiatry 2018; 9:411. [PMID: 30237771 PMCID: PMC6135917 DOI: 10.3389/fpsyt.2018.00411] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 08/13/2018] [Indexed: 12/11/2022] Open
Abstract
Caffeine is a methylxanthine consumed in different contexts to potentiate alertness and reduce fatigue. However, caffeine can induce anxiety at high doses. Caffeine is also a minor psychostimulant that seems to act as an appetite suppressant, but there are also reports indicating that it could stimulate appetite. Dopamine also is involved in food motivation and in behavioral activation. In the present series of experiments, we evaluated the effects of acute administration of caffeine on food consumption under different access conditions. CD1 male adult mice had access to highly palatable food (50% sucrose) in a restricted but habitual context, under continuous or intermittent access as well as under anxiogenic, or effortful conditions. Caffeine (2.5-20.0 mg/kg) increased intake at the highest dose under familiar continuous and intermittent access. However, this high dose reduced food intake in the dark-light paradigm. In contrast, a dopamine-depleting agent, tetrabenazine (TBZ; 1.0-8.0 mg/kg) did not affect food intake in any of those experimental conditions. In the T-maze-barrier task that evaluates seeking and taking of food under effortful conditions, caffeine (10.0 mg/kg) decreased latency to reach the food, but did not affect selection of the high-food density arm that required more effort, or the total amount of food consumed. In contrast, TBZ (4.0 mg/kg) reduced selection of the high food density arm with the barrier, thus affecting amount of food consumed. Interestingly, a small dose of caffeine (5.0 mg/kg) was able to reverse the anergia-inducing effects produced by TBZ in the T-maze. These results suggest that caffeine can potentiate or suppress food consumption depending on the context. Moreover, caffeine did not change appetite, and did not impair orientation toward food under effortful conditions, but it rather helped to achieve the goal by improving speed and by reversing performance to normal levels when fatigue was induced by dopamine depletion.
Collapse
Affiliation(s)
- Mercè Correa
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló, Spain.,Behavioral Neuroscience Division, University of Connecticut, Storrs, CT, United States
| | - Noemí SanMiguel
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló, Spain
| | - Laura López-Cruz
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló, Spain
| | - Carla Carratalá-Ros
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló, Spain
| | | | - John D Salamone
- Behavioral Neuroscience Division, University of Connecticut, Storrs, CT, United States
| |
Collapse
|
63
|
Callaghan CK, Rouine J, O'Mara SM. Potential roles for opioid receptors in motivation and major depressive disorder. PROGRESS IN BRAIN RESEARCH 2018; 239:89-119. [DOI: 10.1016/bs.pbr.2018.07.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
64
|
Yohn SE, Gorka D, Mistry A, Collins S, Qian E, Correa M, Manchanda A, Bogner RH, Salamone JD. Oral Ingestion and Intraventricular Injection of Curcumin Attenuates the Effort-Related Effects of the VMAT-2 Inhibitor Tetrabenazine: Implications for Motivational Symptoms of Depression. JOURNAL OF NATURAL PRODUCTS 2017; 80:2839-2844. [PMID: 28905625 DOI: 10.1021/acs.jnatprod.7b00425] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Effort-related choice tasks are used for studying depressive motivational symptoms such as anergia/fatigue. These studies investigated the ability of the dietary supplement curcumin to reverse the low-effort bias induced by the monoamine storage blocker tetrabenazine. Tetrabenazine shifted effort-related choice in rats, decreasing high-effort lever pressing but increasing chow intake. The effects of tetrabenazine were reversed by oral ingestion of curcumin (80.0-160.0 mg/kg) and infusions of curcumin into the cerebral ventricles (2.0-8.0 μg). Curcumin attenuates the effort-related effects of tetrabenazine in this model via actions on the brain, suggesting that curcumin may be useful for treating human motivational symptoms.
Collapse
Affiliation(s)
| | | | | | | | | | - Merce Correa
- Àrea de Psicobiologia, Universitat Jaume I , Campus de Riu Sec, 12071 Castelló, Spain
| | | | | | | |
Collapse
|
65
|
Maia TV, Conceição VA. The Roles of Phasic and Tonic Dopamine in Tic Learning and Expression. Biol Psychiatry 2017; 82:401-412. [PMID: 28734459 DOI: 10.1016/j.biopsych.2017.05.025] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/08/2017] [Accepted: 05/28/2017] [Indexed: 01/26/2023]
Abstract
Tourette syndrome (TS) prominently involves dopaminergic disturbances, but the precise nature of those disturbances has remained elusive. A substantial body of empirical work and recent computational models have characterized the specific roles of phasic and tonic dopamine (DA) in action learning and selection, respectively. Using insights from this work and models, we suggest that TS involves increases in both phasic and tonic DA, which produce increased propensities for tic learning and expression, respectively. We review the evidence from reinforcement-learning and habit-learning studies in TS, which supports the idea that TS involves increased phasic DA responses; we also review the evidence that tics engage the habit-learning circuitry. On the basis of these findings, we suggest that tics are exaggerated, maladaptive, and persistent motor habits reinforced by aberrant, increased phasic DA responses. Increased tonic DA amplifies the tendency to execute learned tics and also provides a fertile ground of motor hyperactivity for tic learning. We review evidence suggesting that antipsychotics may counter both the increased propensity for tic expression, by increasing excitability in the indirect pathway, and the increased propensity for tic learning, by shifting plasticity in the indirect pathway toward long-term potentiation (and possibly also through more complex mechanisms). Finally, we review evidence suggesting that low doses of DA agonists that effectively treat TS decrease both phasic and tonic DA, thereby also reducing the propensity for both tic learning and tic expression, respectively.
Collapse
Affiliation(s)
- Tiago V Maia
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
| | - Vasco A Conceição
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| |
Collapse
|
66
|
Stuart SA, Wood CM, Robinson ESJ. Using the affective bias test to predict drug-induced negative affect: implications for drug safety. Br J Pharmacol 2017; 174:3200-3210. [PMID: 28782244 PMCID: PMC5595760 DOI: 10.1111/bph.13972] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 07/03/2017] [Accepted: 07/24/2017] [Indexed: 12/02/2022] Open
Abstract
Background and Purpose Predicting the risk of drug‐induced adverse psychiatric effects is important but currently not possible in non‐human species. We investigated whether the affective bias test (ABT) could provide a preclinical method with translational and predictive validity. Experimental Approach The ABT is a bowl‐digging task, which quantifies biases associated with learning and memory. Rats encounter independent learning experiences, on separate days, under either acute manipulations (e.g. pro‐depressant vs. control) or different absolute reward values (e.g. high vs. low). A bias is observed during a preference test when an animal's choices reflect their prior experience. We investigated the effects of putative pro‐depressant drug treatments following acute or chronic administration on the formation of an affective bias or reward‐induced positive bias respectively. Key Results The immunomodulators LPS (10 μg·kg−1), corticosterone (10 and 30 mg·kg−1) and IFN‐α (100 U·kg−1) induced a negative affective bias following acute treatment. Tetrabenazine (1 mg·kg−1) also induced a negative bias, but no effects were observed with varenicline, carbamazepine or montelukast. Chronic treatment with IFN‐α (100 U·kg−1) and retinoic acid (10 mg·kg−1) impaired the formation of a reward‐induced positive bias but did not alter sucrose preference test (SPT). Conclusions and Implications The ABT has the potential to provide a novel approach to predict pro‐depressant risk in a non‐human species. Negative biases induced by acute treatment in the standard version of the task may also predict longer‐term effects on reward processing as shown by the deficit in reward‐induced positive bias following chronic treatment, an effect distinct from anhedonia in the SPT. Linked Articles This article is part of a themed section on Pharmacology of Cognition: a Panacea for Neuropsychiatric Disease? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.19/issuetoc
Collapse
Affiliation(s)
- S A Stuart
- School of Physiology and Pharmacology, Biomedical Sciences, University Walk, University of Bristol, Bristol, UK
| | - C M Wood
- School of Physiology and Pharmacology, Biomedical Sciences, University Walk, University of Bristol, Bristol, UK
| | - E S J Robinson
- School of Physiology and Pharmacology, Biomedical Sciences, University Walk, University of Bristol, Bristol, UK
| |
Collapse
|
67
|
Compromised Dopaminergic Encoding of Reward Accompanying Suppressed Willingness to Overcome High Effort Costs Is a Prominent Prodromal Characteristic of the Q175 Mouse Model of Huntington's Disease. J Neurosci 2017; 36:4993-5002. [PMID: 27147652 DOI: 10.1523/jneurosci.0135-16.2016] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 03/15/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Huntington's disease (HD) is a heritable neurodegenerative disorder caused by expansion of CAG (glutamine) repeats in the HTT gene. A prodromal stage characterized by psychiatric disturbances normally precedes primary motor symptoms and suppressed motivation represents one of the earliest and most common psychiatric symptoms. Although dopamine in the nucleus accumbens (NAc) critically regulates motivation and altered dopamine signaling is implicated in HD, the nature of dopaminergic deficits and contribution to symptoms in HD is poorly understood. We therefore tested whether altered NAc dopamine release accompanies motivational deficits in the Q175 knock-in HD mouse model. Q175 mice express a CAG expansion of the human mutant huntingtin allele in the native mouse genome and gradually manifest symptoms late in life, closely mimicking the genotypic context and disease progression in human HD. Sub-second extracellular dopamine release dynamics were monitored using fast-scan cyclic voltammetry, whereas motivation was assessed using a progressive ratio reinforcement schedule. As the response ratio (lever presses per reward) escalated, Q175 mice exerted less effort to earn fewer rewards versus wild-type (WT). Moreover, dopamine released at reward delivery dynamically encoded increasing reward cost in WT but not Q175 mice. Deficits were specific to situations of high effortful demand as no difference was observed in locomotion, free feeding, hedonic processing, or reward seeking when the response requirement was low. This compromised dopaminergic encoding of reward delivery coincident with suppressed motivation to work for reward in Q175 mice provides novel, neurobiological insight into an established and clinically relevant endophenotype of prodromal HD. SIGNIFICANCE STATEMENT Psychiatric impairments in Huntington's disease (HD) typically manifest early in disease progression, before motor deficits. However, the neurobiological factors contributing to psychiatric symptoms are poorly understood. We used a mouse HD model and assessed whether impaired dopamine release in the nucleus accumbens (NAc), a brain region critical to goal-directed behaviors, accompanies motivational deficits, one of the most common early HD symptoms. HD mice exhibited blunted motivation to work for food reward coincident with diminished dopamine release to reward receipt. Motivational and NAc dopaminergic deficits were not associated with gross motor deficits or impaired food seeking when effortful demands were low. This work identifies a specific prodromal HD phenotype associated with a prominent and previously unidentified neurobiological impairment.
Collapse
|
68
|
Hart EE, Gerson JO, Zoken Y, Garcia M, Izquierdo A. Anterior cingulate cortex supports effort allocation towards a qualitatively preferred option. Eur J Neurosci 2017; 46:1682-1688. [PMID: 28543944 DOI: 10.1111/ejn.13608] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 04/26/2017] [Accepted: 05/14/2017] [Indexed: 11/28/2022]
Abstract
The anterior cingulate cortex (ACC) is known to be involved in effortful choice, yet its role in cost-benefit evaluation of qualitatively different rewards (more/less preferred), beyond magnitude differences (larger/smaller), is poorly understood. Selecting between qualitatively different options is a decision type commonly faced by humans. Here, we assessed the role of ACC on a task that has primarily been used to probe striatal function in motivation. Rats were trained to stable performance on a progressive ratio schedule for sucrose pellets and were then given sham surgeries (control) or excitotoxic NMDA lesions of ACC. Subsequently, a choice was introduced: chow was concurrently available while animals could work for the preferred sucrose pellets. ACC lesions produced a significant decrease in lever presses for sucrose pellets compared to control, whereas chow consumption was unaffected. Lesions had no effect on sucrose pellet preference when both options were freely available. When laboratory chow was not concurrently available, ACC-lesioned rats exhibited similar lever pressing as controls. During a test under specific satiety for sucrose pellets, ACC-lesioned rats also showed intact devaluation effects. The effects of ACC lesions in our task are not mediated by decreased appetite, a change in food preference, a failure to update value or a learning deficit. Taken together, we found that ACC lesions decreased effort for a qualitatively preferred option. These results are discussed with reference to effects of striatal manipulations and our recent report of a role for basolateral amygdala in effortful choice.
Collapse
Affiliation(s)
- Evan E Hart
- Department of Psychology, University of California at Los Angeles, 502 Portola Plaza, 1285 Franz Hall, Los Angeles, CA, 90095-1563, USA
| | - Julian O Gerson
- Department of Psychology, University of California at Los Angeles, 502 Portola Plaza, 1285 Franz Hall, Los Angeles, CA, 90095-1563, USA
| | - Yael Zoken
- Department of Psychology, University of California at Los Angeles, 502 Portola Plaza, 1285 Franz Hall, Los Angeles, CA, 90095-1563, USA
| | - Marisella Garcia
- Department of Psychology, University of California at Los Angeles, 502 Portola Plaza, 1285 Franz Hall, Los Angeles, CA, 90095-1563, USA
| | - Alicia Izquierdo
- Department of Psychology, University of California at Los Angeles, 502 Portola Plaza, 1285 Franz Hall, Los Angeles, CA, 90095-1563, USA.,The Brain Research Institute, University of California at Los Angeles, Los Angeles, CA, USA.,Integrative Center for Learning and Memory, University of California at Los Angeles, Los Angeles, CA, USA.,Integrative Center for Addictions, University of California at Los Angeles, Los Angeles, CA, USA
| |
Collapse
|
69
|
Assessment of a glycine uptake inhibitor in animal models of effort-related choice behavior: implications for motivational dysfunctions. Psychopharmacology (Berl) 2017; 234:1525-1534. [PMID: 28083675 DOI: 10.1007/s00213-016-4523-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 12/23/2016] [Indexed: 12/29/2022]
Abstract
RATIONALE Motivated behavior can be characterized by a substantial exertion of effort, and organisms often make effort-related decisions based upon analyses of work-related response costs and reinforcement preference. Moreover, alterations in effort-based choice can be seen in people with major depression and schizophrenia. Effort-related decision making is studied using tasks offering choices between high effort options leading to highly valued reinforces vs low effort/low reward options. Interference with dopamine (DA) transmission by administration of the DA D2 family antagonist haloperidol biases behavior towards the lower effort option that can be obtained with minimal work, and previous research has shown that DA interacts with other transmitters, including adenosine and GABA, to regulate effort-based choice. OBJECTIVES The present studies focused upon the ability of the glycine transport inhibitor bitopertin to attenuate haloperidol-induced shifts in effort-related choice behavior. METHODS Effort-based choice in rats was assessed using the concurrent fixed ratio (FR) 5/chow feeding choice task and the T-maze barrier choice procedure. RESULTS Haloperidol shifted effort-based choice, biasing animals towards the low effort option in each task. Co-administration of bitopertin (1.0-10.0 mg/kg) significantly attenuated haloperidol-induced shifts in choice behavior, but the same doses of bitopertin had no effect when administered alone. CONCLUSIONS These results indicated that elevation of extracellular glycine via inhibition of glycine uptake was able to reverse the effects of D2 antagonism. Increases in extracellular glycine, possibly through actions on the glycine allosteric site on the NMDA receptor, may be a useful strategy for treating motivational dysfunctions in humans.
Collapse
|
70
|
Hart EE, Izquierdo A. Basolateral amygdala supports the maintenance of value and effortful choice of a preferred option. Eur J Neurosci 2017; 45:388-397. [PMID: 27977047 DOI: 10.1111/ejn.13497] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/26/2016] [Accepted: 11/29/2016] [Indexed: 11/29/2022]
Abstract
The basolateral amygdala (BLA) is known to be involved in appetitive behavior, yet its role in cost-benefit choice of qualitatively different rewards (more/less preferred), beyond magnitude differences (larger/smaller), is poorly understood. We assessed the effects of BLA inactivations on effortful choice behavior. Rats were implanted with cannulae in BLA and trained to stable lever pressing for sucrose pellets on a progressive ratio schedule. Rats were then introduced to a choice: chow was concurrently available while they could work for the preferred sucrose pellets. Rats were infused with either vehicle control (aCSF) or baclofen/muscimol prior to test. BLA inactivations produced a significant decrease in lever presses for sucrose pellets compared to vehicle, and chow consumption was unaffected. Inactivation had no effect on sucrose pellet preference when both options were freely available. Critically, when lab chow was not concurrently available, BLA inactivations had no effect on the number of lever presses for sucrose pellets, indicating that primary motivation in the absence of choice remains intact with BLA offline. After a test under specific satiety for sucrose pellets, BLA inactivation rendered animals less sensitive to devaluation relative to control. The effects of BLA inactivations in our task are not mediated by decreased appetite, an inability to perform the task, a change in food preference, or decrements in primary motivation. Taken together, BLA supports the specific value and effortful choice of a preferred option.
Collapse
Affiliation(s)
- Evan E Hart
- Department of Psychology, University of California at Los Angeles, 1285 Franz Hall Box, Los Angeles, CA, 95156, USA
| | - Alicia Izquierdo
- Department of Psychology, University of California at Los Angeles, 1285 Franz Hall Box, Los Angeles, CA, 95156, USA.,The Brain Research Institute, University of California at Los Angeles, Los Angeles, CA, USA.,Integrative Center for Learning and Memory, University of California at Los Angeles, Los Angeles, CA, USA.,Integrative Center for Addictions, University of California at Los Angeles, Los Angeles, CA, USA
| |
Collapse
|
71
|
Felger JC, Treadway MT. Inflammation Effects on Motivation and Motor Activity: Role of Dopamine. Neuropsychopharmacology 2017; 42:216-241. [PMID: 27480574 PMCID: PMC5143486 DOI: 10.1038/npp.2016.143] [Citation(s) in RCA: 244] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Revised: 07/13/2016] [Accepted: 07/27/2016] [Indexed: 01/18/2023]
Abstract
Motivational and motor deficits are common in patients with depression and other psychiatric disorders, and are related to symptoms of anhedonia and motor retardation. These deficits in motivation and motor function are associated with alterations in corticostriatal neurocircuitry, which may reflect abnormalities in mesolimbic and mesostriatal dopamine (DA). One pathophysiologic pathway that may drive changes in DAergic corticostriatal circuitry is inflammation. Biomarkers of inflammation such as inflammatory cytokines and acute-phase proteins are reliably elevated in a significant proportion of psychiatric patients. A variety of inflammatory stimuli have been found to preferentially target basal ganglia function to lead to impaired motivation and motor activity. Findings have included inflammation-associated reductions in ventral striatal neural responses to reward anticipation, decreased DA and DA metabolites in cerebrospinal fluid, and decreased availability, and release of striatal DA, all of which correlated with symptoms of reduced motivation and/or motor retardation. Importantly, inflammation-associated symptoms are often difficult to treat, and evidence suggests that inflammation may decrease DA synthesis and availability, thus circumventing the efficacy of standard pharmacotherapies. This review will highlight the impact of administration of inflammatory stimuli on the brain in relation to motivation and motor function. Recent data demonstrating similar relationships between increased inflammation and altered DAergic corticostriatal circuitry and behavior in patients with major depressive disorder will also be presented. Finally, we will discuss the mechanisms by which inflammation affects DA neurotransmission and relevance to novel therapeutic strategies to treat reduced motivation and motor symptoms in patients with high inflammation.
Collapse
Affiliation(s)
- Jennifer C Felger
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute, Emory University, Atlanta, GA, USA
| | - Michael T Treadway
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute, Emory University, Atlanta, GA, USA
- Department of Psychology, Emory University, Atlanta, GA, USA
| |
Collapse
|
72
|
Epilogue – Distinct Motivations and Their Differentiated Mechanisms: Reflections on the Emerging Neuroscience of Human Motivation. ACTA ACUST UNITED AC 2016. [DOI: 10.1108/s0749-742320160000019009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
73
|
Yohn SE, Arif Y, Haley A, Tripodi G, Baqi Y, Müller CE, Miguel NS, Correa M, Salamone JD. Effort-related motivational effects of the pro-inflammatory cytokine interleukin-6: pharmacological and neurochemical characterization. Psychopharmacology (Berl) 2016; 233:3575-86. [PMID: 27497935 DOI: 10.1007/s00213-016-4392-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 07/18/2016] [Indexed: 12/15/2022]
Abstract
RATIONALE Motivational dysfunctions such as anergia, fatigue, and reduced effort expenditure are common in patients with depression and other disorders. Pro-inflammatory cytokines are implicated in depression, and cytokine administration induces motivational deficits in humans. OBJECTIVES These studies focused on the effects of the cytokine interleukin-6 (IL-6) on effort-related decision-making. METHODS Rats were assessed using the concurrent fixed ratio 5-lever pressing/chow feeding choice procedure, which measures the tendency of rats to work for a preferred food (high carbohydrate pellets) in the presence of a concurrently available but less preferred substitute (lab chow). RESULTS IL-6 (2.0-8.0 μg/kg IP) shifted choice behavior, significantly decreasing lever pressing and increasing chow intake. Further experiments showed that the adenosine A2A antagonist MSX-3 and the stimulant methylphenidate attenuated the effort-related impairments produced by IL-6, increasing lever pressing and decreasing chow intake in IL-6 treated rats. The same doses of IL-6 did not alter food intake or preference in parallel free-feeding choice studies, demonstrating that these low doses were not altering preference for the high carbohydrate pellets or generally suppressing appetite. Also, IL-6 did not affect body temperature. Microdialysis studies showed that 8.0 μg/kg IL-6 significantly decreased extracellular dopamine in nucleus accumbens core. CONCLUSIONS In summary, IL-6 reduces the tendency to work for food, even at low doses that do not produce fever or loss of appetite. Dopaminergic mechanisms may be involved in these effort-related effects. This research has implications for the involvement of cytokines in motivational dysfunctions such as anergia and fatigue.
Collapse
Affiliation(s)
- Samantha E Yohn
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Yumna Arif
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Allison Haley
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Guiseppe Tripodi
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Younis Baqi
- Universität Bonn, Pharma-Zentrum Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie, Bonn, Germany
- Department of Chemistry, Sultan Qaboos University, Muscat, Oman
| | - Christa E Müller
- Universität Bonn, Pharma-Zentrum Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie, Bonn, Germany
| | - Noemi San Miguel
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain
| | - Mercè Correa
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain
| | - John D Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA.
| |
Collapse
|
74
|
Scheggi S, Melis M, De Felice M, Aroni S, Muntoni AL, Pelliccia T, Gambarana C, De Montis MG, Pistis M. PPARα modulation of mesolimbic dopamine transmission rescues depression-related behaviors. Neuropharmacology 2016; 110:251-259. [PMID: 27457507 DOI: 10.1016/j.neuropharm.2016.07.024] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/19/2016] [Accepted: 07/20/2016] [Indexed: 01/08/2023]
Abstract
Depressive disorders cause a substantial burden for the individual and the society. Key depressive symptoms can be modeled in animals and enable the development of novel therapeutic interventions. Chronic unavoidable stress disrupts rats' competence to escape noxious stimuli and self-administer sucrose, configuring a depression model characterized by escape deficit and motivational anhedonia associated to impaired dopaminergic responses to sucrose in the nucleus accumbens shell (NAcS). Repeated treatments that restore these responses also relieve behavioral symptoms. Ventral tegmental area (VTA) dopamine neurons encode reward and motivation and are implicated in the neuropathology of depressive-like behaviors. Peroxisome proliferator-activated receptors type-α (PPARα) acutely regulate VTA dopamine neuron firing via β2 subunit-containing nicotinic acetylcholine receptors (β2*nAChRs) through phosphorylation and this effect is predictive of antidepressant-like effects. Here, by combining behavioral, electrophysiological and biochemical techniques, we studied the effects of repeated PPARα stimulation by fenofibrate on mesolimbic dopamine system. We found decreased β2*nAChRs phosphorylation levels and a switch from tonic to phasic activity of dopamine cells in the VTA, and increased phosphorylation of dopamine and cAMP-regulated phosphoprotein Mr 32,000 (DARPP-32) in the NAcS. We then investigated whether long-term fenofibrate administration to stressed rats reinstated the decreased DARPP-32 response to sucrose and whether this effect translated into antidepressant-like properties. Fenofibrate restored dopaminergic responses to appetitive stimuli, reactivity to aversive stimuli and motivation to self-administer sucrose. Overall, this study suggests PPARα as new targets for antidepressant therapies endowed with motivational anti-anhedonic properties, further supporting the role of an unbalanced mesolimbic dopamine system in pathophysiology of depressive disorders.
Collapse
Affiliation(s)
- Simona Scheggi
- Department of Molecular and Developmental Medicine, University of Siena, 53100 Siena, Italy
| | - Miriam Melis
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, Italy
| | - Marta De Felice
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, Italy
| | - Sonia Aroni
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, Italy
| | - Anna Lisa Muntoni
- Neuroscience Institute, National Research Council of Italy, Section of Cagliari, Italy
| | - Teresa Pelliccia
- Department of Molecular and Developmental Medicine, University of Siena, 53100 Siena, Italy
| | - Carla Gambarana
- Department of Molecular and Developmental Medicine, University of Siena, 53100 Siena, Italy
| | | | - Marco Pistis
- Division of Neuroscience and Clinical Pharmacology, Department of Biomedical Sciences, University of Cagliari, 09042 Monserrato, Italy; Neuroscience Institute, National Research Council of Italy, Section of Cagliari, Italy.
| |
Collapse
|
75
|
Chong TTJ, Bonnelle V, Husain M. Quantifying motivation with effort-based decision-making paradigms in health and disease. PROGRESS IN BRAIN RESEARCH 2016; 229:71-100. [PMID: 27926453 DOI: 10.1016/bs.pbr.2016.05.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Motivation can be characterized as a series of cost-benefit valuations, in which we weigh the amount of effort we are willing to expend (the cost of an action) in return for particular rewards (its benefits). Human motivation has traditionally been measured with self-report and questionnaire-based tools, but an inherent limitation of these methods is that they are unable to provide a mechanistic explanation of the processes underlying motivated behavior. A major goal of current research is to quantify motivation objectively with effort-based decision-making paradigms, by drawing on a rich literature from nonhuman animals. Here, we review this approach by considering the development of these paradigms in the laboratory setting over the last three decades, and their more recent translation to understanding choice behavior in humans. A strength of this effort-based approach to motivation is that it is capable of capturing the wide range of individual differences, and offers the potential to dissect motivation into its component elements, thus providing the basis for more accurate taxonomic classifications. Clinically, modeling approaches might provide greater sensitivity and specificity to diagnosing disorders of motivation, for example, in being able to detect subclinical disorders of motivation, or distinguish a disorder of motivation from related but separate syndromes, such as depression. Despite the great potential in applying effort-based paradigms to index human motivation, we discuss several caveats to interpreting current and future studies, and the challenges in translating these approaches to the clinical setting.
Collapse
Affiliation(s)
- T T-J Chong
- Macquarie University, Sydney, NSW, Australia; ARC Centre of Excellence in Cognition and its Disorders, Macquarie University, Sydney, NSW, Australia; Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Clayton, VIC, Australia.
| | - V Bonnelle
- University of Oxford, Oxford, United Kingdom
| | - M Husain
- University of Oxford, Oxford, United Kingdom; John Radcliffe Hospital, Oxford, United Kingdom
| |
Collapse
|
76
|
Yohn SE, Errante EE, Rosenbloom-Snow A, Somerville M, Rowland M, Tokarski K, Zafar N, Correa M, Salamone JD. Blockade of uptake for dopamine, but not norepinephrine or 5-HT, increases selection of high effort instrumental activity: Implications for treatment of effort-related motivational symptoms in psychopathology. Neuropharmacology 2016; 109:270-280. [PMID: 27329556 DOI: 10.1016/j.neuropharm.2016.06.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/07/2016] [Accepted: 06/17/2016] [Indexed: 12/21/2022]
Abstract
Deficits in behavioral activation, exertion of effort, and other psychomotor/motivational symptoms are frequently seen in people with depression and other disorders. Depressed people show a decision bias towards selection of low effort activities, and animal tests of effort-related decision making are being used as models of motivational dysfunctions seen in psychopathology. The present studies investigated the ability of drugs that block dopamine transport (DAT), norepinephrine transport (NET), and serotonin transport (SERT) to modulate work output in rats responding on a test of effort-related decision making (i.e., a progressive ratio (PROG)/chow feeding choice task). With this task, rats choose between working for a preferred food (high carbohydrate pellets) by lever pressing on a PROG schedule vs. obtaining a less preferred lab chow that is freely available in the chamber. The present studies focused on the effects of the selective DAT inhibitor GBR12909, the selective SERT inhibitor fluoxetine, and the selective NET inhibitors desipramine and atomoxetine. Acute and repeated administration of GBR12909 shifted choice behavior, increasing measures of PROG lever pressing but decreasing chow intake. In contrast, fluoxetine, desipramine and atomoxetine failed to increase lever pressing output, and actually decreased it at higher doses. In the behaviorally effective dose range, GBR12909 elevated extracellular dopamine levels in accumbens core as measured by microdialysis, but fluoxetine, desipramine and atomoxetine decreased extracellular dopamine. Thus, blockade of DAT increases selection of the high effort instrumental activity, while inhibition of SERT or NET does not. These results have implications for the use of monoamine uptake inhibitors for the treatment of effort-related psychiatric symptoms in humans.
Collapse
Affiliation(s)
- Samantha E Yohn
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Emily E Errante
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA
| | | | - Matthew Somerville
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Margaret Rowland
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Kristin Tokarski
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Nadia Zafar
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Merce Correa
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA; Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain
| | - John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT, 06261-1020, USA.
| |
Collapse
|
77
|
Yohn SE, Gogoj A, Haque A, Lopez-Cruz L, Haley A, Huxley P, Baskin P, Correa M, Salamone JD. Evaluation of the effort-related motivational effects of the novel dopamine uptake inhibitor PRX-14040. Pharmacol Biochem Behav 2016; 148:84-91. [PMID: 27296079 DOI: 10.1016/j.pbb.2016.06.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 06/08/2016] [Accepted: 06/10/2016] [Indexed: 12/29/2022]
Affiliation(s)
- Samantha E Yohn
- Department of Psychology, University of Connecticut, Storrs, CT 06261-1020, USA
| | - Augustyna Gogoj
- Department of Psychology, University of Connecticut, Storrs, CT 06261-1020, USA
| | - Aileen Haque
- Department of Psychology, University of Connecticut, Storrs, CT 06261-1020, USA
| | - Laura Lopez-Cruz
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain
| | - Allison Haley
- Department of Psychology, University of Connecticut, Storrs, CT 06261-1020, USA
| | - Philip Huxley
- Prexa Pharmaceuticals, 745 Atlantic Ave., 3rd floor, Boston, MA 02111, USA
| | - Patricia Baskin
- Prexa Pharmaceuticals, 745 Atlantic Ave., 3rd floor, Boston, MA 02111, USA
| | - Merce Correa
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071 Castelló, Spain
| | - John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT 06261-1020, USA.
| |
Collapse
|
78
|
Salamone JD, Yohn SE, López-Cruz L, San Miguel N, Correa M. Activational and effort-related aspects of motivation: neural mechanisms and implications for psychopathology. Brain 2016; 139:1325-47. [PMID: 27189581 PMCID: PMC5839596 DOI: 10.1093/brain/aww050] [Citation(s) in RCA: 222] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 01/15/2016] [Accepted: 02/12/2016] [Indexed: 01/18/2023] Open
Abstract
Motivation has been defined as the process that allows organisms to regulate their internal and external environment, and control the probability, proximity and availability of stimuli. As such, motivation is a complex process that is critical for survival, which involves multiple behavioural functions mediated by a number of interacting neural circuits. Classical theories of motivation suggest that there are both directional and activational aspects of motivation, and activational aspects (i.e. speed and vigour of both the instigation and persistence of behaviour) are critical for enabling organisms to overcome work-related obstacles or constraints that separate them from significant stimuli. The present review discusses the role of brain dopamine and related circuits in behavioural activation, exertion of effort in instrumental behaviour, and effort-related decision-making, based upon both animal and human studies. Impairments in behavioural activation and effort-related aspects of motivation are associated with psychiatric symptoms such as anergia, fatigue, lassitude and psychomotor retardation, which cross multiple pathologies, including depression, schizophrenia, and Parkinson's disease. Therefore, this review also attempts to provide an interdisciplinary approach that integrates findings from basic behavioural neuroscience, behavioural economics, clinical neuropsychology, psychiatry, and neurology, to provide a coherent framework for future research and theory in this critical field. Although dopamine systems are a critical part of the brain circuitry regulating behavioural activation, exertion of effort, and effort-related decision-making, mesolimbic dopamine is only one part of a distributed circuitry that includes multiple neurotransmitters and brain areas. Overall, there is a striking similarity between the brain areas involved in behavioural activation and effort-related processes in rodents and in humans. Animal models of effort-related decision-making are highly translatable to humans, and an emerging body of evidence indicates that alterations in effort-based decision-making are evident in several psychiatric and neurological disorders. People with major depression, schizophrenia, and Parkinson's disease show evidence of decision-making biases towards a lower exertion of effort. Translational studies linking research with animal models, human volunteers, and clinical populations are greatly expanding our knowledge about the neural basis of effort-related motivational dysfunction, and it is hoped that this research will ultimately lead to improved treatment for motivational and psychomotor symptoms in psychiatry and neurology.
Collapse
Affiliation(s)
- John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA
| | - Samantha E Yohn
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA
| | - Laura López-Cruz
- Àrea de Psicobiologia, Universitat Jaume I, 12071 Castelló, Spain
| | - Noemí San Miguel
- Àrea de Psicobiologia, Universitat Jaume I, 12071 Castelló, Spain
| | - Mercè Correa
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA Àrea de Psicobiologia, Universitat Jaume I, 12071 Castelló, Spain
| |
Collapse
|
79
|
Effects of lisdexamfetamine and s-citalopram, alone and in combination, on effort-related choice behavior in the rat. Psychopharmacology (Berl) 2016; 233:949-60. [PMID: 26694811 DOI: 10.1007/s00213-015-4176-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 11/25/2015] [Indexed: 12/29/2022]
Abstract
RATIONALE Effort-related motivational symptoms, such as anergia, psychomotor retardation, and fatigue, are an important aspect of depression and other disorders. Motivational symptoms are resistant to some treatments, including serotonin transport (SERT) inhibitors. OBJECTIVES Tests of effort-based choice using operant behavior tasks (e.g., concurrent lever pressing/ chow feeding tasks) can be used as animal models of motivational symptoms. Tests of effort-related choice allow animals to choose between high-effort actions that lead to more highly valued rewards vs. low-effort alternatives that lead to less valued rewards (i.e., less preferred or lower magnitude). Rats treated with the vesicular monoamine transport inhibitor tetrabenazine, or the cytokine interleukin-1β (IL-1β), which are associated with depressive symptoms in humans, can alter effort-related choice, reducing selection of the high effort alternative (lever pressing) while increasing intake of freely available chow. METHODS The present studies focused upon the ability of lisdexamfetamine (LDX) to increase exertion of effort in rats responding on effort-based choice tasks under several different conditions. RESULTS LDX attenuated the shift from fixed ratio 5 lever pressing to chow intake induced by tetrabenazine and IL-1β. In contrast, the SERT inhibitor s-citalopram failed to reverse the effects of tetrabenazine. When given in combination with tetrabenazine+s-citalopram, LDX significantly increased lever pressing output compared to tetrabenaine+citalopram alone. LDX also increased work output in rats responding on a progressive ratio/chow feeding choice task. CONCLUSIONS LDX can increase work output in rats responding on effort-based choice tasks, which may have implications for understanding the neurochemistry of motivational symptoms in humans.
Collapse
|
80
|
Chesworth R, Brown RM, Kim JH, Ledent C, Lawrence AJ. Adenosine 2A receptors modulate reward behaviours for methamphetamine. Addict Biol 2016; 21:407-21. [PMID: 25612195 DOI: 10.1111/adb.12225] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Addiction to methamphetamine (METH) is a global health problem for which there are no approved pharmacotherapies. The adenosine 2A (A2 A ) receptor presents a potential therapeutic target for METH abuse due to its modulatory effects on striatal dopamine and glutamate transmission. Notably, A2 A receptor signalling has been implicated in the rewarding effects of alcohol, cocaine and opiates; yet, the role of this receptor in METH consumption and seeking is essentially unknown. Therefore, the current study used A2 A knockout (KO) mice to assess the role of A2 A in behaviours relevant to METH addiction. METH conditioned place preference was absent in A2 A KO mice compared with wild-type (WT) littermates. Repeated METH treatment produced locomotor sensitization in both genotypes; however, sensitization was attenuated in A2 A KO mice in a dose-related manner. METH intravenous self-administration was intact in A2 A KO mice over a range of doses and schedules of reinforcement. However, the motivation to self-administer was reduced in A2 A KO mice. Regression analysis further supported the observation that the motivation to self-administer METH was reduced in A2 A KO mice even when self-administration was similar to WT mice. Sucrose self-administration was also reduced in A2 A KO mice but only at higher schedules of reinforcement. Collectively, these data suggest that A2 A signalling is critically required to integrate rewarding and motivational properties of both METH and natural rewards.
Collapse
Affiliation(s)
- Rose Chesworth
- Behavioural Neuroscience Division; Florey Institute of Neuroscience and Mental Health; Australia
- Florey Department of Neuroscience and Mental Health; University of Melbourne; Australia
| | - Robyn M. Brown
- Behavioural Neuroscience Division; Florey Institute of Neuroscience and Mental Health; Australia
- Florey Department of Neuroscience and Mental Health; University of Melbourne; Australia
- Department of Neurosciences; Medical University of South Carolina; Charleston SC USA
| | - Jee Hyun Kim
- Behavioural Neuroscience Division; Florey Institute of Neuroscience and Mental Health; Australia
- Florey Department of Neuroscience and Mental Health; University of Melbourne; Australia
| | - Catherine Ledent
- Institut de Recherche Interdisciplinaire; Faculté de Médecine; Université de Bruxelles; Belgium
| | - Andrew J. Lawrence
- Behavioural Neuroscience Division; Florey Institute of Neuroscience and Mental Health; Australia
- Florey Department of Neuroscience and Mental Health; University of Melbourne; Australia
| |
Collapse
|
81
|
Salamone JD, Correa M, Yohn S, Lopez Cruz L, San Miguel N, Alatorre L. The pharmacology of effort-related choice behavior: Dopamine, depression, and individual differences. Behav Processes 2016; 127:3-17. [PMID: 26899746 DOI: 10.1016/j.beproc.2016.02.008] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 02/08/2016] [Accepted: 02/12/2016] [Indexed: 12/22/2022]
Abstract
This review paper is focused upon the involvement of mesolimbic dopamine (DA) and related brain systems in effort-based processes. Interference with DA transmission affects instrumental behavior in a manner that interacts with the response requirements of the task, such that rats with impaired DA transmission show a heightened sensitivity to ratio requirements. Impaired DA transmission also affects effort-related choice behavior, which is assessed by tasks that offer a choice between a preferred reinforcer that has a high work requirement vs. less preferred reinforcer that can be obtained with minimal effort. Rats and mice with impaired DA transmission reallocate instrumental behavior away from food-reinforced tasks with high response costs, and show increased selection of low reinforcement/low cost options. Tests of effort-related choice have been developed into models of pathological symptoms of motivation that are seen in disorders such as depression and schizophrenia. These models are being employed to explore the effects of conditions associated with various psychopathologies, and to assess drugs for their potential utility as treatments for effort-related symptoms. Studies of the pharmacology of effort-based choice may contribute to the development of treatments for symptoms such as psychomotor slowing, fatigue or anergia, which are seen in depression and other disorders.
Collapse
Affiliation(s)
- John D Salamone
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA.
| | - Merce Correa
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA; Area de Psicobiol., Dept. Psic., Universitat de Jaume I, Castelló 12071, Spain
| | - Samantha Yohn
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA
| | - Laura Lopez Cruz
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA; Area de Psicobiol., Dept. Psic., Universitat de Jaume I, Castelló 12071, Spain
| | - Noemi San Miguel
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA; Area de Psicobiol., Dept. Psic., Universitat de Jaume I, Castelló 12071, Spain
| | | |
Collapse
|
82
|
Correa M, Pardo M, Bayarri P, López-Cruz L, San Miguel N, Valverde O, Ledent C, Salamone JD. Choosing voluntary exercise over sucrose consumption depends upon dopamine transmission: effects of haloperidol in wild type and adenosine A₂AKO mice. Psychopharmacology (Berl) 2016; 233:393-404. [PMID: 26554387 DOI: 10.1007/s00213-015-4127-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/12/2015] [Indexed: 11/25/2022]
Abstract
RATIONALE Mesolimbic dopamine (DA) regulates behavioral activation and effort-related decision-making in motivated behaviors. Mesolimbic DA D2 receptors are co-localized with adenosine A2A receptors, and they interact in an antagonistic manner. OBJECTIVES A T-maze task was developed to assess dopaminergic involvement in preference between a reinforcer that involves vigorous voluntary activity (running wheel) and a reinforcer that requires minimal behavioral activation (sucrose pellets). Haloperidol (D2 antagonist) was administered to adenosine A2A receptor knockout (A2AKO) and wild-type (WT) littermate controls to assess the involvement of these two receptors in the selection of running wheel activity versus sucrose consumption. RESULTS Under control conditions, mice spent more time running and less time eating. In WT mice, haloperidol reduced time running but actually increased time-consuming sucrose. However, A2AKO mice did not show the haloperidol-induced shift from running wheel activity to sucrose intake. Prefeeding reduced sucrose consumption in the T-maze in both strains, indicating that this paradigm is sensitive to motivational devaluation. Haloperidol increased c-Fos immunoreactivity in anterior cingulate cortex (ACg) and nucleus accumbens (Acb) core of WT but not KO mice. CONCLUSIONS These results indicate that after DA antagonism, the preference for vigorous physical activity is reduced, while palatable food selection increases. Adenosine A2A receptor deletion provides resistance to these effects of D2 receptor antagonism. These two receptors in Acb core and ACg seem to be involved in the regulation of the intrinsic reinforcing characteristics of voluntary exercise but not in the regulation of the primary reinforcing characteristics of palatable sedentary reinforcers.
Collapse
Affiliation(s)
- Mercè Correa
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Marta Pardo
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Pilar Bayarri
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Laura López-Cruz
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Noemí San Miguel
- Department of Psychobiology, Universitat Jaume I, Castelló, Spain.
| | - Olga Valverde
- Department of Experimental and Health Sciences, Universitat Pompeu Fabra and IMIM-Hospital del Mar Research Institute, Barcelona, Spain.
| | - Catherine Ledent
- Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire, Université Libre de Bruxelles, IRIBHM, Bruxelles, Belgium.
| | - John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT, USA.
| |
Collapse
|
83
|
Not All Antidepressants Are Created Equal: Differential Effects of Monoamine Uptake Inhibitors on Effort-Related Choice Behavior. Neuropsychopharmacology 2016; 41:686-94. [PMID: 26105139 PMCID: PMC4707815 DOI: 10.1038/npp.2015.188] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 05/21/2015] [Accepted: 05/21/2015] [Indexed: 11/08/2022]
Abstract
Motivated behavior can be characterized by behavioral activation and high work output. Moreover, people with depression and other disorders show effort-related motivational symptoms, such as anergia, psychomotor retardation, and fatigue. Effort-based decision making is studied using tasks offering choices between high effort options leading to highly valued reinforcers vs low effort/low reward options, and such tasks could be useful as animal models of motivational symptoms. In the present studies the effort-related effects of the vesicular monoamine transport (VMAT-2) inhibitor tetrabenazine (TBZ) were investigated. TBZ blocks vesicular storage and also produces depressive symptoms in humans. Moreover, TBZ alters effort-based choice in rats, biasing animals toward low effort alternatives. The present studies investigated the ability of acute administration of various monoamine uptake inhibitors to reverse the effects of TBZ. Effort-related effects of TBZ were attenuated by the catecholamine uptake inhibitor and antidepressant bupropion, and this effect of bupropion was reversed by either D1 or D2 family antagonism. The effort-related effects of TBZ were also attenuated by the selective dopamine uptake blocker GBR12909. The 5-HT uptake inhibitor fluoxetine and the norepinephrine uptake inhibitor desipramine failed to reverse the effects of TBZ, and higher doses of these drugs, given alone or in combination with TBZ, led to further behavioral impairments. These results indicate that drugs acting on dopamine transmission are relatively effective at reversing the effort-related effects of TBZ, and are consistent with the hypothesis that drugs that enhance dopamine transmission may be effective at treating effort-related psychiatric symptoms in humans.
Collapse
|
84
|
de Freitas CM, Busanello A, Schaffer LF, Peroza LR, Krum BN, Leal CQ, Ceretta APC, da Rocha JBT, Fachinetto R. Behavioral and neurochemical effects induced by reserpine in mice. Psychopharmacology (Berl) 2016; 233:457-67. [PMID: 26514557 DOI: 10.1007/s00213-015-4118-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 10/15/2015] [Indexed: 01/11/2023]
Abstract
RATIONALE Reserpine, a monoamine-depleting agent, which irreversibly and non-selectively blocks the vesicular monoamine transporter, has been used as an animal model to study several neurological disorders, including tardive dyskinesia and Parkinson's disease. OBJECTIVE The purpose of this study was to examine if motor deficits induced by reserpine in mice could be related to alterations in the expression of dopaminergic system proteins such as tyrosine hydroxylase (TH) and dopamine transporter (DAT) and in the activity of monoamine oxidase (MAO). METHODS Mice received either vehicle or reserpine (0.1, 0.5, or 1 mg/kg, s.c.) for four consecutive days. Two, 20, or 60 days after reserpine withdrawal, behavioral, and neurochemical changes were evaluated. RESULTS Reserpine at a dose of 0.5 and 1 mg/kg increased vacuous chewing movements (VCMs) and reduced locomotion. Behavioral changes were accompanied by reduction in TH immunoreactivity in the striatum evaluated on days 2 and 20 after the last injection of 1 mg/kg reserpine. Furthermore, negative correlations were found between VCM and MAO-A or MAO-B on day 2 and TH striatal immunoreactivity on day 20 after the last injection of 1 mg/kg reserpine. A positive correlation was observed between VCMs and DAT immunoreactivity in the substantia nigra on day 2 after the last injection of 0.5 mg/kg reserpine. CONCLUSIONS These findings suggest that the pharmacological blockage of vesicular monoamine transporter (VMAT) by reserpine caused neurochemical and behavioral alterations in mice.
Collapse
Affiliation(s)
- Catiuscia Molz de Freitas
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Alcindo Busanello
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Larissa Finger Schaffer
- Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Luis Ricardo Peroza
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Bárbara Nunes Krum
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | | | | | - João Batista Teixeira da Rocha
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
| | - Roselei Fachinetto
- Programa de Pós-Graduação em Ciências Biológicas: Bioquímica Toxicológica, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil. .,Programa de Pós-Graduação em Farmacologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil. .,Departamento de Fisiologia e Farmacologia, Centro de Ciências da Saúde, 97105-900, Santa Maria, RS, Brazil.
| |
Collapse
|
85
|
Heath CJ, Phillips BU, Bussey TJ, Saksida LM. Measuring Motivation and Reward‐Related Decision Making in the Rodent Operant Touchscreen System. ACTA ACUST UNITED AC 2016; 74:8.34.1-8.34.20. [DOI: 10.1002/0471142301.ns0834s74] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Christopher J. Heath
- Department of Psychology and MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge Cambridge United Kingdom
| | - Benjamin U. Phillips
- Department of Psychology and MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge Cambridge United Kingdom
| | - Timothy J. Bussey
- Department of Psychology and MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge Cambridge United Kingdom
| | - Lisa M. Saksida
- Department of Psychology and MRC/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge Cambridge United Kingdom
| |
Collapse
|
86
|
The role of dopamine in the pathophysiology and treatment of apathy. PROGRESS IN BRAIN RESEARCH 2016; 229:389-426. [DOI: 10.1016/bs.pbr.2016.05.007] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
87
|
Podurgiel SJ, Spencer T, Kovner R, Baqi Y, Müller CE, Correa M, Salamone JD. Induction of oral tremor in mice by the acetylcholinesterase inhibitor galantamine: Reversal with adenosine A2A antagonism. Pharmacol Biochem Behav 2016; 140:62-7. [DOI: 10.1016/j.pbb.2015.10.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 10/06/2015] [Accepted: 10/08/2015] [Indexed: 01/29/2023]
|
88
|
Krügel U. Purinergic receptors in psychiatric disorders. Neuropharmacology 2015; 104:212-25. [PMID: 26518371 DOI: 10.1016/j.neuropharm.2015.10.032] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/23/2015] [Accepted: 10/23/2015] [Indexed: 02/07/2023]
Abstract
Psychiatric disorders describe different mental or behavioral patterns, causing suffering or poor coping of ordinary life with manifold presentations. Multifactorial processes can contribute to their development and progression. Purinergic neurotransmission and neuromodulation in the brain have attracted increasing therapeutic interest in the field of psychiatry. Purine nucleotides and nucleosides are well recognized as signaling molecules mediating cell to cell communication. The actions of ATP are mediated by ionotropic P2X and metabotropic P2Y receptor subfamilies, whilst the actions of adenosine are mediated by P1 (A1 or A2) adenosine receptors. Purinergic mechanisms and specific receptor subtypes have been shown to be linked to the regulation of many aspects of behavior and mood and to dysregulation in pathological processes of brain function. In this review the recent knowledge on the role of purinergic receptors in the two most frequent psychiatric diseases, major depression and schizophrenia, as well as on related animal models is summarized. At present the most promising data for therapeutic strategies derive from investigations of the adenosine system emphasizing a unique function of A2A receptors at neurons and astrocytes in these disorders. Among the P2 receptor family, in particular P2X7 and P2Y1 receptors were related to disturbances in major depression and schizophrenia, respectively. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
Collapse
Affiliation(s)
- Ute Krügel
- Rudolf Boehm Institute of Pharmacology and Toxicology, Universität Leipzig, Härtelstrasse 16-18, 04107 Leipzig, Germany.
| |
Collapse
|
89
|
Salamone JD, Koychev I, Correa M, McGuire P. Neurobiological basis of motivational deficits in psychopathology. Eur Neuropsychopharmacol 2015; 25:1225-38. [PMID: 25435083 DOI: 10.1016/j.euroneuro.2014.08.014] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 08/16/2014] [Accepted: 08/20/2014] [Indexed: 12/29/2022]
Abstract
In recent years, there has been increasing emphasis on the importance of motivational symptoms in depression, schizophrenia and other disorders. The present review discusses the conceptual background related to the construct of motivation, and provides a framework that for research on both physiological and pathological aspects of motivation. Particular emphasis is placed on what is known about the neurobiological basis of activational aspects of motivation, including studies from animal models. The role of limbic/prefrontal/striatal circuitry in behavioral activation and effort-related functions is examined, and the utility of behavioral tasks of effort-based decision making as models of motivational symptoms is discussed. We also review the neurobiology of motivational symptoms in relation to psychopathology, and issues related to the language used to characterize motivational dysfunctions are considered. The literature suggests that research on the neurobiology of motivational dysfunction in psychopathology, at both clinical and preclinical levels, could inform the development of novel and more effective treatments for a range of CNS disorders.
Collapse
Affiliation(s)
- John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA.
| | - Ivan Koychev
- Department of Psychosis Studies, Institute of Psychiatry, King's College London, DeCrespigny Park, London SE5 8AF, UK.
| | - Mercè Correa
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA; Department of Psychobiology, University Jaume I, Castelló, Spain.
| | - Philip McGuire
- Department of Psychosis Studies, Institute of Psychiatry, King's College London, DeCrespigny Park, London SE5 8AF, UK.
| |
Collapse
|
90
|
Podurgiel SJ, Milligan MN, Yohn SE, Purcell LJ, Contreras-Mora HM, Correa M, Salamone JD. Fluoxetine Administration Exacerbates Oral Tremor and Striatal Dopamine Depletion in a Rodent Pharmacological Model of Parkinsonism. Neuropsychopharmacology 2015; 40:2240-7. [PMID: 25759301 PMCID: PMC4613615 DOI: 10.1038/npp.2015.69] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 01/15/2015] [Accepted: 01/31/2015] [Indexed: 02/06/2023]
Abstract
The cardinal motor symptoms of Parkinson's disease (PD) include resting tremor, akinesia, bradykinesia, and rigidity, and these motor abnormalities can be modeled in rodents by administration of the VMAT-2 (type-2 vesicular monoamine transporter) inhibitor tetrabenazine (9,10-dimethoxy-3-(2-methylpropyl)-1,3,4,6,7, 11b hexahydrobenzo[a]quinolizin-2-one; TBZ). Depression is also commonly associated with PD, and clinical data indicate that selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine ((±)-N-methyl-γ-[4-(trifluoromethyl)phenoxy]benzenepropanamine hydrochloride; FLX) are frequently used to treat depression in PD patients. The aim of the present study was to characterize the effect of FLX on the motor dysfunctions induced by a low dose of TBZ (0.75 mg/kg), and investigate the neural mechanisms involved. This low dose of TBZ was selected based on studies with rat models of depressive symptoms. In rats, coadministration of FLX (2.5, 5.0, and 10.0 mg/kg) increased TBZ-induced oral tremor (tremulous jaw movements), and decreased locomotor activity compared with administration of TBZ alone. Coadministration of the serotonin 5-HT2A/2C antagonist mianserin (2.5 and 5.0 mg/kg) attenuated the increase in oral tremor induced by coadministration of TBZ (0.75 mg/kg) with FLX (5.0 mg/kg). Consistent with these behavioral data, coadministration of TBZ and FLX decreased DA tissue levels in the rat ventrolateral neostriatum compared with TBZ alone, and coadministration of mianserin with TBZ and FLX attenuated this effect, increasing DA tissue levels compared with the TBZ/FLX condition. These data suggest that SSRI administration in PD patients may result in worsening of motor symptoms, at least in part, by exacerbating existing DA depletions through 5-HT2A/2C-mediated modulation of DA neurotransmission.
Collapse
Affiliation(s)
| | | | - Samantha E Yohn
- Department of Psychology, University of Connecticut, Storrs, CT, USA
| | - Laura J Purcell
- Department of Psychology, University of Connecticut, Storrs, CT, USA
| | | | - Mercè Correa
- Àrea de Psicobiologia, Universitat Jaume I, Castelló, Spain
| | - John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT, USA
| |
Collapse
|
91
|
Yohn SE, Santerre JL, Nunes EJ, Kozak R, Podurgiel SJ, Correa M, Salamone JD. The role of dopamine D1 receptor transmission in effort-related choice behavior: Effects of D1 agonists. Pharmacol Biochem Behav 2015; 135:217-26. [DOI: 10.1016/j.pbb.2015.05.003] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2015] [Revised: 05/05/2015] [Accepted: 05/09/2015] [Indexed: 12/27/2022]
|
92
|
Pardo M, López-Cruz L, San Miguel N, Salamone JD, Correa M. Selection of sucrose concentration depends on the effort required to obtain it: studies using tetrabenazine, D1, D2, and D3 receptor antagonists. Psychopharmacology (Berl) 2015; 232:2377-91. [PMID: 25647696 DOI: 10.1007/s00213-015-3872-7] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 01/16/2015] [Indexed: 12/30/2022]
Abstract
RATIONALE Low doses of dopamine (DA) antagonists and accumbens DA depletions reduce food-reinforced instrumental behavior but do not impair primary food motivation, causing animals to reallocate behavior away from food-reinforced tasks with high response requirements and select less effortful alternatives. However, it is uncertain if this same pattern of effects would occur if sucrose was used as the reinforcer. OBJECTIVES These experiments studied the impact of DA depletion and antagonism on performance of an effort-related choice task using sucrose as the reinforcer, as well as sucrose consumption, preference, and taste reactivity tests. METHODS The effects of DA manipulations were assessed using a task in which rats chose between lever pressing on a fixed ratio 7 schedule for 5.0 % sucrose versus freely consuming a less concentrated solution (0.3 %). RESULTS The DA depleting agent tetrabenazine shifted effort-related choice, decreasing lever pressing for 5.0 % sucrose but increasing intake of the concurrently available 0.3 % sucrose. Tetrabenazine did not affect sucrose appetitive taste reactivity, or sucrose consumption or preference, in free consumption tests. The D1 antagonist ecopipam and the D2 antagonist haloperidol also shifted choice behavior at doses that did not alter sucrose consumption or preference. In contrast, sucrose pre-exposure reduced consumption across all conditions. D3 antagonism had no effects. CONCLUSIONS D1 and D2 receptor blockade and DA depletion reduce the tendency to work for sucrose under conditions that leave fundamental aspects of sucrose motivation (intake, preference, hedonic reactivity) intact. These findings have implications for studies employing sucrose intake or preference in animal models of depression.
Collapse
Affiliation(s)
- Marta Pardo
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain
| | - Laura López-Cruz
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain
| | - Noemí San Miguel
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain
| | - John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Mercè Correa
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain. .,Department of Psychology, University of Connecticut, Storrs, CT, 06269-1020, USA.
| |
Collapse
|
93
|
Minor TR, Hanff TC. Adenosine signaling in reserpine-induced depression in rats. Behav Brain Res 2015; 286:184-91. [DOI: 10.1016/j.bbr.2015.02.032] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 02/11/2015] [Accepted: 02/16/2015] [Indexed: 02/05/2023]
|
94
|
Yohn SE, Thompson C, Randall PA, Lee CA, Müller CE, Baqi Y, Correa M, Salamone JD. The VMAT-2 inhibitor tetrabenazine alters effort-related decision making as measured by the T-maze barrier choice task: reversal with the adenosine A2A antagonist MSX-3 and the catecholamine uptake blocker bupropion. Psychopharmacology (Berl) 2015; 232:1313-23. [PMID: 25323625 DOI: 10.1007/s00213-014-3766-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 10/03/2014] [Indexed: 01/28/2023]
Abstract
RATIONALE Depressed people show effort-related motivational symptoms, such as anergia, retardation, lassitude, and fatigue. Animal tests can model these motivational symptoms, and the present studies characterized the effort-related effects of the vesicular monoamine transport (VMAT-2) inhibitor tetrabenazine. Tetrabenazine produces depressive symptoms in humans and, at low doses, preferentially depletes dopamine. OBJECTIVES The current studies investigated the effects of tetrabenazine on effort-based decision making using the T-maze barrier task. METHODS Rats were tested in a T-maze in which the choice arms of the maze contain different reinforcement densities, and under some conditions, a vertical barrier was placed in the high-density arm to provide an effort-related challenge. The first experiment assessed the effects of tetrabenazine under different maze conditions: a barrier in the arm with 4 food pellets and 2 pellets in the no barrier arm (4-2 barrier), 4 pellets in one arm and 2 pellets in the other with no barrier in either arm (no barrier), and 4 pellets in the barrier arm with no pellets in the other (4-0 barrier). RESULTS Tetrabenazine (0.25-0.75 mg/kg IP) decreased selection of the high cost/high reward arm when the barrier was present, but had no effect on choice under the no barrier and 4-0 barrier conditions. The effects of tetrabenazine on barrier climbing in the 4-2 condition were reversed by the adenosine A2A antagonist MSX-3 and the catecholamine uptake inhibitor and antidepressant bupropion. CONCLUSIONS These studies have implications for the development of animal models of the motivational symptoms of depression and other disorders.
Collapse
Affiliation(s)
- Samantha E Yohn
- Division of Behavioral Neuroscience, Department of Psychology, University of Connecticut, Storrs, CT, 06269-1020, USA
| | | | | | | | | | | | | | | |
Collapse
|
95
|
Müller T. Valbenazine granted breakthrough drug status for treating tardive dyskinesia. Expert Opin Investig Drugs 2015; 24:737-42. [DOI: 10.1517/13543784.2015.1029573] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
96
|
Randall PA, Lee CA, Podurgiel SJ, Hart E, Yohn SE, Jones M, Rowland M, López-Cruz L, Correa M, Salamone JD. Bupropion increases selection of high effort activity in rats tested on a progressive ratio/chow feeding choice procedure: implications for treatment of effort-related motivational symptoms. Int J Neuropsychopharmacol 2015; 18:pyu017. [PMID: 25575584 PMCID: PMC4368885 DOI: 10.1093/ijnp/pyu017] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Depression and related disorders are characterized by deficits in behavioral activation, exertion of effort, and other psychomotor/motivational dysfunctions. Depressed patients show alterations in effort-related decision making and a bias towards selection of low effort activities. It has been suggested that animal tests of effort-related decision making could be useful as models of motivational dysfunctions seen in psychopathology. METHODS Because clinical studies have suggested that inhibition of catecholamine uptake may be a useful strategy for treatment of effort-related motivational symptoms, the present research assessed the ability of bupropion to increase work output in rats responding on a test of effort-related decision-making (ie, a progressive ratio/chow feeding choice task). With this task, rats can choose between working for a preferred food (high-carbohydrate pellets) by lever pressing on a progressive ratio schedule vs obtaining a less preferred laboratory chow that is freely available in the chamber. RESULTS Bupropion (10.0-40.0 mg/kg intraperitoneal) significantly increased all measures of progressive ratio lever pressing, but decreased chow intake. These effects were greatest in animals with low baseline levels of work output on the progressive ratio schedule. Because accumbens dopamine is implicated in effort-related processes, the effects of bupropion on markers of accumbens dopamine transmission were examined. Bupropion elevated extracellular dopamine levels in accumbens core as measured by microdialysis and increased phosphorylated dopamine and cyclic-AMP related phosphoprotein 32 kDaltons (pDARPP-32) immunoreactivity in a manner consistent with D1 and D2 receptor stimulation. CONCLUSION The ability of bupropion to increase exertion of effort in instrumental behavior may have implications for the pathophysiology and treatment of effort-related motivational symptoms in humans.
Collapse
|
97
|
Salamone JD, Pardo M, Yohn SE, López-Cruz L, SanMiguel N, Correa M. Mesolimbic Dopamine and the Regulation of Motivated Behavior. Curr Top Behav Neurosci 2015; 27:231-57. [PMID: 26323245 DOI: 10.1007/7854_2015_383] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
It has been known for some time that nucleus accumbens dopamine (DA) is involved in aspects of motivation , but theoretical approaches to understanding the functions of DA have continued to evolve based upon emerging data and novel concepts. Although it has become traditional to label DA neurons as "reward" neurons, the actual findings are more complicated than that, because they indicate that DA neurons can respond to a variety of motivationally significant stimuli. Moreover, it is important to distinguish between aspects of motivation that are differentially affected by dopaminergic manipulations. Studies that involve nucleus accumbens DA antagonism or depletion indicate that accumbens DA does not mediate primary food motivation or appetite. Nevertheless, DA is involved in appetitive and aversive motivational processes including behavioral activation , exertion of effort, sustained task engagement, and Pavlovian-to-instrumental transfer. Interference with accumbens DA transmission affects instrumental behavior in a manner that interacts with the response requirements of the task and also shifts effort-related choice behavior, biasing animals toward low-effort alternatives. Dysfunctions of mesolimbic DA may contribute to motivational symptoms seen in various psychopathologies, including depression , schizophrenia, parkinsonism, and other disorders.
Collapse
Affiliation(s)
- John D Salamone
- Department of Psychology, University of Connecticut, Storrs, CT, 06269-1020, USA.
| | - Marta Pardo
- Àrea de Psicobiologia, Universitat Jaume I, 12071, Castelló, Spain
| | - Samantha E Yohn
- Department of Psychology, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Laura López-Cruz
- Àrea de Psicobiologia, Universitat Jaume I, 12071, Castelló, Spain
| | - Noemí SanMiguel
- Àrea de Psicobiologia, Universitat Jaume I, 12071, Castelló, Spain
| | - Mercè Correa
- Department of Psychology, University of Connecticut, Storrs, CT, 06269-1020, USA.,Àrea de Psicobiologia, Universitat Jaume I, 12071, Castelló, Spain
| |
Collapse
|
98
|
Motivational assessment of mice using the touchscreen operant testing system: effects of dopaminergic drugs. Psychopharmacology (Berl) 2015; 232:4043-57. [PMID: 26156636 PMCID: PMC4600476 DOI: 10.1007/s00213-015-4009-8] [Citation(s) in RCA: 48] [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: 03/15/2015] [Accepted: 06/28/2015] [Indexed: 12/29/2022]
Abstract
RATIONALE Touchscreens are widely used to examine rodent cognition. Current paradigms require animals to view stimuli and nose poke at an appropriate touchscreen location. After responding, there is little screen interaction and, as infra-red touchscreens eliminate the need for physical contact, minimal somatosensory feedback. It is therefore unclear if touchscreens can support the vigorous, repetitive responding required in paradigms like progressive ratio (PR) for assessing motivation and effort-related choice (ERC) for assessing decision-making. OBJECTIVES This study aims to adapt and validate PR and ERC for the rodent touchscreen. METHODS Male C57Bl/6 mice were trained until responding on PR stabilised. Amphetamine, sulpiride and raclopride were administered via the intraperitoneal route to modify performance. Mice were transferred to ERC and paradigm parameters adjusted to demonstrate behavioural modification. ERC reward preference was assessed by home cage choice analysis. RESULTS PR performance stabilised within seven sessions. Amphetamine (1 mg/kg) increased and raclopride (0.3 mg/kg) decreased performance by 63 and 28 %, respectively, with a 20-min injection-test interval. Sulpiride (50 mg/kg) decreased performance by 19 % following a 40-min injection-test interval. Increasing ERC operant requirements shifted responding from the operant response-dependent preferred reward towards the freely available alternative. CONCLUSIONS Vigorous, repetitive responding is sustainable in touchscreen PR and ERC and task validation mirrors non-touchscreen versions. Thus, motivation and reward-related decision-making can be measured directly with touchscreens and can be evaluated prior to cognitive testing in the same apparatus to avoid confounding by motivational factors.
Collapse
|
99
|
The dopamine reuptake inhibitor MRZ-9547 increases progressive ratio responding in rats. Int J Neuropsychopharmacol 2014; 17:2045-56. [PMID: 24964269 DOI: 10.1017/s1461145714000996] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Drugs that are able to shift effort-related decision making in intact rats towards high-effort response options are largely unknown. Here, we examined the effects of two candidate drugs, MRZ-9547 and its l-enantiomer MRZ-9546 on progressive ratio (PR) responding using two different tasks, a standard PR task that involves increasing ratio requirements and a PR/chow feeding choice task in which animals can lever press for preferred food pellets under a PR schedule or approach freely available less preferred lab chow. Furthermore, we assessed the mechanisms of action of both drugs using in vitro-assay methods and in vivo-microdialysis. Results reveal that MRZ-9547 is a selective dopamine transporter (DAT) inhibitor that moderately stimulated striatal dopamine release. MRZ-9546 was a much less potent DAT inhibitor. Furthermore, MRZ-9547 dose dependently increased the tendency to work for food reinforcement both in the standard PR task and the PR/chow feeding choice task, MRZ-9546 was considerably less active. Relative to MRZ-9547, other DAT-interfering drugs had only moderate (methylphenidate) or marginal (modafinil, d-amphetamine) stimulant effects on PR responding in either task. Collectively, our data demonstrate that the DAT inhibitor MRZ-9547 can markedly stimulate PR responding and shift effort-related decision making in intact rats towards high-effort response options. An analysis of effort-related decision making in rodents could provide an animal model for motivational dysfunctions related to effort expenditure such as fatigue, e.g. in Parkinson's disease or major depression. Our findings suggest that DAT inhibitors such as MRZ-9547 could be potentially useful for treating energy-related symptoms in neurological or neuropsychiatric disorders.
Collapse
|
100
|
Randall PA, Lee CA, Nunes EJ, Yohn SE, Nowak V, Khan B, Shah P, Pandit S, Vemuri VK, Makriyannis A, Baqi Y, Müller CE, Correa M, Salamone JD. The VMAT-2 inhibitor tetrabenazine affects effort-related decision making in a progressive ratio/chow feeding choice task: reversal with antidepressant drugs. PLoS One 2014; 9:e99320. [PMID: 24937131 PMCID: PMC4061002 DOI: 10.1371/journal.pone.0099320] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 05/13/2014] [Indexed: 01/13/2023] Open
Abstract
Behavioral activation is a fundamental feature of motivation, and organisms frequently make effort-related decisions based upon evaluations of reinforcement value and response costs. Furthermore, people with major depression and other disorders often show anergia, psychomotor retardation, fatigue, and alterations in effort-related decision making. Tasks measuring effort-based decision making can be used as animal models of the motivational symptoms of depression, and the present studies characterized the effort-related effects of the vesicular monoamine transport (VMAT-2) inhibitor tetrabenazine. Tetrabenazine induces depressive symptoms in humans, and also preferentially depletes dopamine (DA). Rats were assessed using a concurrent progressive ratio (PROG)/chow feeding task, in which they can either lever press on a PROG schedule for preferred high-carbohydrate food, or approach and consume a less-preferred lab chow that is freely available in the chamber. Previous work has shown that the DA antagonist haloperidol reduced PROG work output on this task, but did not reduce chow intake, effects that differed substantially from those of reinforcer devaluation or appetite suppressant drugs. The present work demonstrated that tetrabenazine produced an effort-related shift in responding on the PROG/chow procedure, reducing lever presses, highest ratio achieved and time spent responding, but not reducing chow intake. Similar effects were produced by administration of the subtype selective DA antagonists ecopipam (D1) and eticlopride (D2), but not by the cannabinoid CB1 receptor neutral antagonist and putative appetite suppressant AM 4413, which suppressed both lever pressing and chow intake. The adenosine A2A antagonist MSX-3, the antidepressant and catecholamine uptake inhibitor bupropion, and the MAO-B inhibitor deprenyl, all reversed the impairments induced by tetrabenazine. This work demonstrates the potential utility of the PROG/chow procedure as a rodent model of the effort-related deficits observed in depressed patients.
Collapse
Affiliation(s)
- Patrick A. Randall
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Christie A. Lee
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Eric J. Nunes
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Samantha E. Yohn
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Victoria Nowak
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Bilal Khan
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Priya Shah
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - Saagar Pandit
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
| | - V. Kiran Vemuri
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States of America
| | - Alex Makriyannis
- Center for Drug Discovery, Northeastern University, Boston, Massachusetts, United States of America
| | - Younis Baqi
- Pharma-Zentrum Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie, Universität Bonn, Bonn, Germany
- Department of Chemistry, Faculty of Science, Sultan Qaboos University, Muscat, Oman
| | - Christa E. Müller
- Pharma-Zentrum Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie, Universität Bonn, Bonn, Germany
| | - Merce Correa
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
- Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, Castelló, Spain
| | - John D. Salamone
- Department of Psychology, University of Connecticut, Storrs, Connecticut, United States of America
- * E-mail:
| |
Collapse
|