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Hersey M, Mereu M, Jones CS, Bartole MK, Chen AY, Cao J, Hiranita T, Chun LE, Lopez JP, Katz JL, Newman AH, Tanda G. Dual DAT and sigma receptor inhibitors attenuate cocaine effects on nucleus accumbens dopamine dynamics in rats. Eur J Neurosci 2024; 59:2436-2449. [PMID: 38444104 PMCID: PMC11108740 DOI: 10.1111/ejn.16293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 01/10/2024] [Accepted: 02/07/2024] [Indexed: 03/07/2024]
Abstract
Psychostimulant use disorders (PSUD) are prevalent; however, no FDA-approved medications have been made available for treatment. Previous studies have shown that dual inhibitors of the dopamine transporter (DAT) and sigma receptors significantly reduce the behavioral/reinforcing effects of cocaine, which have been associated with stimulation of extracellular dopamine (DA) levels resulting from DAT inhibition. Here, we employ microdialysis and fast scan cyclic voltammetry (FSCV) procedures to investigate the effects of dual inhibitors of DAT and sigma receptors in combination with cocaine on nucleus accumbens shell (NAS) DA dynamics in naïve male Sprague Dawley rats. In microdialysis studies, administration of rimcazole (3, 10 mg/kg; i.p.) or its structural analog SH 3-24 (1, 3 mg/kg; i.p.), compounds that are dual inhibitors of DAT and sigma receptors, significantly reduced NAS DA efflux stimulated by increasing doses of cocaine (0.1, 0.3, 1.0 mg/kg; i.v.). Using the same experimental conditions, in FSCV tests, we show that rimcazole pretreatments attenuated cocaine-induced stimulation of evoked NAS DA release but produced no additional effect on DA clearance rate. Under the same conditions, JJC8-091, a modafinil analog and dual inhibitor of DAT and sigma receptors, similarly attenuated cocaine-induced stimulation of evoked NAS DA release but produced no additional effect on DA clearance rate. Our results provide the neurochemical groundwork towards understanding actions of dual inhibitors of DAT and sigma receptors on DA dynamics that likely mediate the behavioral effects of psychostimulants like cocaine.
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Affiliation(s)
- Melinda Hersey
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
| | - Maddalena Mereu
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
| | - Claire S. Jones
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
| | | | - Andy Y. Chen
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
| | - Jianjing Cao
- Medicinal Chemistry Section, NIDA IRP, Baltimore, MD 21224, USA
| | | | - Lauren E. Chun
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
| | - Jessica P. Lopez
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
| | | | - Amy Hauck Newman
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
- Medicinal Chemistry Section, NIDA IRP, Baltimore, MD 21224, USA
| | - Gianluigi Tanda
- Medication Development Program, NIDA IRP, Baltimore, MD 21224, USA
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2
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Ecevitoglu A, Meka N, Rotolo RA, Edelstein GA, Srinath S, Beard KR, Carratala-Ros C, Presby RE, Cao J, Okorom A, Newman AH, Correa M, Salamone JD. Potential therapeutics for effort-related motivational dysfunction: assessing novel atypical dopamine transport inhibitors. Neuropsychopharmacology 2024:10.1038/s41386-024-01826-1. [PMID: 38429498 DOI: 10.1038/s41386-024-01826-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 01/28/2024] [Accepted: 02/05/2024] [Indexed: 03/03/2024]
Abstract
People with depression and other neuropsychiatric disorders can experience motivational dysfunctions such as fatigue and anergia, which involve reduced exertion of effort in goal-directed activity. To model effort-related motivational dysfunction, effort-based choice tasks can be used, in which rats can select between obtaining a preferred reinforcer by high exertion of effort vs. a low effort/less preferred option. Preclinical data indicate that dopamine transport (DAT) inhibitors can reverse pharmacologically-induced low-effort biases and increase selection of high-effort options in effort-based choice tasks. Although classical DAT blockers like cocaine can produce undesirable effects such as liability for misuse and psychotic reactions, not all DAT inhibitors have the same neurochemical profile. The current study characterized the effort-related effects of novel DAT inhibitors that are modafinil analogs and have a range of binding profiles and neurochemical actions (JJC8-088, JJC8-089, RDS3-094, and JJC8-091) by using two different effort-related choice behavior tasks in male Sprague-Dawley rats. JJC8-088, JJC8-089, and RDS3-094 significantly reversed the low-effort bias induced by the VMAT-2 inhibitor tetrabenazine, increasing selection of high-effort fixed ratio 5 lever pressing vs. chow intake. In addition, JJC8-089 reversed the effects of tetrabenazine in female rats. JJC8-088 and JJC8-089 also increased selection of high-effort progressive ratio responding in a choice task. However, JJC8-091 failed to produce these outcomes, potentially due to its unique pharmacological profile (i.e., binding to an occluded conformation of DAT). Assessment of a broad range of DAT inhibitors with different neurochemical characteristics may lead to the identification of compounds that are useful for treating motivational dysfunction in humans.
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Affiliation(s)
- Alev Ecevitoglu
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Nicolette Meka
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Renee A Rotolo
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Gayle A Edelstein
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Sonya Srinath
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Kathryn R Beard
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Carla Carratala-Ros
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
- Area de Psicobiología. Universitat Jaume I, Castelló, Spain
| | - Rose E Presby
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA
| | - Jianjing Cao
- Medicinal Chemistry Section, NIDA-Intramural Research Program, Baltimore, MD, 21224, USA
| | - Amarachi Okorom
- Medicinal Chemistry Section, NIDA-Intramural Research Program, Baltimore, MD, 21224, USA
| | - Amy H Newman
- Medicinal Chemistry Section, NIDA-Intramural Research Program, Baltimore, MD, 21224, USA
| | - Mercè Correa
- Area de Psicobiología. Universitat Jaume I, Castelló, Spain
| | - John D Salamone
- Psychological Sciences, University of Connecticut, Storrs, CT, 06269-1020, USA.
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Okorom AV, Camacho-Hernandez GA, Salomon K, Lee KH, Ku TC, Cao J, Won SJ, Friedman J, Lam J, Paule J, Rais R, Klein B, Xi ZX, Shi L, Loland CJ, Newman AH. Modifications to 1-(4-(2-Bis(4-fluorophenyl)methyl)sulfinyl)alkyl Alicyclic Amines That Improve Metabolic Stability and Retain an Atypical DAT Inhibitor Profile. J Med Chem 2024; 67:709-727. [PMID: 38117239 DOI: 10.1021/acs.jmedchem.3c02037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
Atypical dopamine transporter (DAT) inhibitors have shown therapeutic potential in the preclinical models of psychostimulant use disorders (PSUD). In rats, 1-(4-(2-((bis(4-fluorophenyl)methyl)sulfinyl)ethyl)-piperazin-1-yl)-propan-2-ol (JJC8-091, 3b) was effective in reducing the reinforcing effects of both cocaine and methamphetamine but did not exhibit psychostimulant behaviors itself. Improvements in DAT affinity and metabolic stability were desirable for discovering pipeline drug candidates. Thus, a series of 1-(4-(2-bis(4-fluorophenyl)methyl)sulfinyl)alkyl alicyclic amines were synthesized and evaluated for binding affinities at DAT and the serotonin transporter (SERT). Replacement of the piperazine with either a homopiperazine or a piperidine ring system was well tolerated at DAT (Ki range = 3-382 nM). However, only the piperidine analogues (20a-d) showed improved metabolic stability in rat liver microsomes as compared to the previously reported analogues. Compounds 12b and 20a appeared to retain an atypical DAT inhibitor profile, based on negligible locomotor activity in mice and molecular modeling that predicts binding to an inward-facing conformation of DAT.
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Affiliation(s)
- Amarachi V Okorom
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Gisela Andrea Camacho-Hernandez
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Kristine Salomon
- Laboratory for Membrane Protein Dynamics, Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Kuo Hao Lee
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Therese C Ku
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Jianjing Cao
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Sung Joon Won
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Jacob Friedman
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
- Department of Neurology, Johns Hopkins Drug Discovery, The Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Jenny Lam
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
- Department of Neurology, Johns Hopkins Drug Discovery, The Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - James Paule
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
- Department of Neurology, Johns Hopkins Drug Discovery, The Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Rana Rais
- Department of Neurology, Johns Hopkins Drug Discovery, The Johns Hopkins University School of Medicine, 855 North Wolfe Street, Baltimore, Maryland 21205, United States
| | - Benjamin Klein
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Zheng-Xiong Xi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Lei Shi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Claus J Loland
- Laboratory for Membrane Protein Dynamics, Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Amy Hauck Newman
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
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González-Saiz F, Trujols J, Vergara-Moragues E. Cocaine Effect Expectancies among Patients with Cocaine Use Disorder with and without Adult Attention Deficit Hyperactivity Disorder: Are There Any Relevant Differences? J Psychoactive Drugs 2024; 56:76-87. [PMID: 36480506 DOI: 10.1080/02791072.2022.2151951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 09/05/2022] [Accepted: 09/23/2022] [Indexed: 12/14/2022]
Abstract
Cocaine use could be modulated by drug expectancies based on previously experienced subjective effects. Some patients perceive a paradoxical calming effect after cocaine use. This study was performed to explore cocaine effect expectancies in patients diagnosed with cocaine use disorder, with and without co-occurring adult attention deficit hyperactivity disorder (ADHD). Secondly, we sought to empirically determine the presence of this paradoxical calming effect after cocaine use in patients with co-occurring adult ADHD to identify the individuals most at risk of cocaine use and relapse. Cross-sectional study using a consecutive sampling method of patients diagnosed with cocaine use disorder (n = 221) treated at public therapeutic communities in Andalusia (Spain). Participants completed a battery of instruments to assess the following variables: cocaine effect expectancies, paradoxical calming effect, adult ADHD, and other co-occurring psychiatric disorders. A multivariate binary logistic regression analysis showed that two variables, the paradoxical calming effect and antisocial personality disorder (ASPD), were independently associated with the probability of being diagnosed with adult ADHD (OR = 3.43, 95% CI = 1.88-6.26 and OR = 3.42, 95% CI = 1.30-8.95, respectively). The presence of a paradoxical calming reaction to cocaine and/or a diagnosis of ASPD in patients with cocaine use disorder increases the diagnostic suspicion of co-occurring adult ADHD.
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Affiliation(s)
- Francisco González-Saiz
- Community Mental Health Unit of Villamartin, Hospital Universitario de Jerez, Cádiz, Spain
- Department of Neuroscience, Area of Psychiatry, University of Cadiz, Cadiz, Spain
- CIBERSAM (Network of Biomedical Research Centres for Mental Health), Madrid, Spain
| | - Joan Trujols
- CIBERSAM (Network of Biomedical Research Centres for Mental Health), Madrid, Spain
- Addictive Behaviours Unit, Department of Psychiatry, Hospital de la Santa Creu I Sant Pau, Biomedical Research Institute Sant Pau (IIB Sant Pau), Barcelona, Spain
| | - Esperanza Vergara-Moragues
- Department of Psychobiology and Behavioural Science. Complutense University of Madrid (UCM), Madrid, Spain
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Hersey M, Tanda G. Modafinil, an atypical CNS stimulant? ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2023; 99:287-326. [PMID: 38467484 DOI: 10.1016/bs.apha.2023.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Modafinil is a central nervous system stimulant approved for the treatment of narcolepsy and sleep disorders. Due to its wide range of biochemical actions, modafinil has been explored for other potential therapeutic uses. Indeed, it has shown promise as a therapy for cognitive disfunction resulting from neurologic disorders like ADHD, and as a smart drug in non-medical settings. The mechanism(s) of actions underlying the therapeutic efficacy of this agent remains largely elusive. Modafinil is known to inhibit the dopamine transporter, thus decreasing dopamine reuptake following neuronal release, an effect shared by addictive psychostimulants. However, modafinil is unique in that only a few cases of dependence on this drug have been reported, as compared to other psychostimulants. Moreover, modafinil has been tested, with some success, as a potential therapeutic agent to combat psychostimulant and other substance use disorders. Modafinil has additional, but less understood, actions on other neurotransmitter systems (GABA, glutamate, serotonin, norepinephrine, etc.). These interactions, together with its ability to activate selected brain regions, are likely one of the keys to understand its unique pharmacology and therapeutic activity as a CNS stimulant. In this chapter, we outline the pharmacokinetics and pharmacodynamics of modafinil that suggest it has an "atypical" CNS stimulant profile. We also highlight the current approved and off label uses of modafinil, including its beneficial effects as a treatment for sleep disorders, cognitive functions, and substance use disorders.
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Affiliation(s)
- Melinda Hersey
- Medication Development Program, NIDA-IRP, NIH, Baltimore, MD, United States
| | - Gianluigi Tanda
- Medication Development Program, NIDA-IRP, NIH, Baltimore, MD, United States.
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6
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Keighron JD, Bonaventura J, Li Y, Yang JW, DeMarco EM, Hersey M, Cao J, Sandtner W, Michaelides M, Sitte HH, Newman AH, Tanda G. Interactions of calmodulin kinase II with the dopamine transporter facilitate cocaine-induced enhancement of evoked dopamine release. Transl Psychiatry 2023; 13:202. [PMID: 37311803 DOI: 10.1038/s41398-023-02493-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/17/2023] [Accepted: 05/26/2023] [Indexed: 06/15/2023] Open
Abstract
Typical and atypical dopamine uptake inhibitors (DUIs) prefer distinct conformations of the dopamine transporter (DAT) to form ligand-transporter complexes, resulting in markedly different effects on behavior, neurochemistry, and potential for addiction. Here we show that cocaine and cocaine-like typical psychostimulants elicit changes in DA dynamics distinct from those elicited by atypical DUIs, as measured via voltammetry procedures. While both classes of DUIs reduced DA clearance rate, an effect significantly related to their DAT affinity, only typical DUIs elicited a significant stimulation of evoked DA release, an effect unrelated to their DAT affinity, which suggests a mechanism of action other than or in addition to DAT blockade. When given in combination, typical DUIs enhance the stimulatory effects of cocaine on evoked DA release while atypical DUIs blunt them. Pretreatments with an inhibitor of CaMKIIα, a kinase that interacts with DAT and that regulates synapsin phosphorylation and mobilization of reserve pools of DA vesicles, blunted the effects of cocaine on evoked DA release. Our results suggest a role for CaMKIIα in modulating the effects of cocaine on evoked DA release without affecting cocaine inhibition of DA reuptake. This effect is related to a specific DAT conformation stabilized by cocaine. Moreover, atypical DUIs, which prefer a distinct DAT conformation, blunt cocaine's neurochemical and behavioral effects, indicating a unique mechanism underlying their potential as medications for treating psychostimulant use disorder.
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Affiliation(s)
- Jacqueline D Keighron
- Medication Development Program, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
- Department of Biological and Chemical Science, New York Institute of Technology, Old Westbury, NY, USA
| | - Jordi Bonaventura
- Biobehavioral Imaging & Molecular Neuropsychopharmacology Unit, Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
- Department of Pathology and Experimental Therapeutics, Institut de Neurociències, Universitat de Barcelona, L'Hospitalet de Llobregat, Catalonia, Spain
| | - Yang Li
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Jae-Won Yang
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Emily M DeMarco
- Medication Development Program, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Melinda Hersey
- Medication Development Program, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Jianjing Cao
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Walter Sandtner
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Michael Michaelides
- Biobehavioral Imaging & Molecular Neuropsychopharmacology Unit, Neuroimaging Research Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Harald H Sitte
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Amy Hauck Newman
- Medication Development Program, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA
| | - Gianluigi Tanda
- Medication Development Program, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, USA.
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Effects of isoflurane anesthesia on addictive behaviors in rats. Psychopharmacology (Berl) 2022; 239:3621-3632. [PMID: 36109391 DOI: 10.1007/s00213-022-06236-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 09/05/2022] [Indexed: 10/14/2022]
Abstract
RATIONALE Recently, it has been suggested that isoflurane might reduce dopamine release from rat midbrain dopaminergic neurons, the neurobiological substrate implicated in the reinforcing effects of abused drugs and nondrug rewards. However, little is known about effects of isoflurane on neurobehavioral activity associated with chronic exposure to psychoactive substances. OBJECTIVE The present study was designed to investigate the effects of isoflurane on cocaine-reinforced behavior. Using behavioral paradigm in rats, we evaluated the effects of isoflurane on cocaine self-administration under fixed ratio (FR) and progressive ratio (PR) schedules of reinforcement. We also tested the effects of isoflurane on lever responding by nondrug reinforcers (sucrose and food) in drug-naive rats to control for the nonselective effects of isoflurane on cocaine- and nicotine-taking behavior. To further assess the ability of isoflurane to modulate the motivation for taking a drug, we evaluated the effects of isoflurane on nicotine self-administration. Using different groups of rats, the effects of isoflurane on the locomotor activity induced by a single intraperitoneal injection of cocaine (15 mg/kg) were also examined. RESULTS Isoflurane significantly suppressed the self-administration of cocaine and nicotine without affecting food consumption. Unlike food-reinforced responding, responding for sucrose reinforcement was decreased by isoflurane. Isoflurane reduced breaking points under a PR schedule of reinforcement in a dose-dependent manner, indicating its efficacy in decreasing the incentive value of cocaine. Isoflurane also attenuated acute cocaine-induced hyperlocomotion. CONCLUSIONS The results provided evidence that isoflurane decreases cocaine- and nicotine-reinforced responses, while isoflurane effect is not selective for cocaine- and nicotine-maintained responding. These results suggest that isoflurane inhibitions of cocaine- and nicotine-maintenance responses may be related to decreased effects of dopamine, and further investigation will need to elucidate this relationship.
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Treadway MT, Salamone JD. Vigor, Effort-Related Aspects of Motivation and Anhedonia. Curr Top Behav Neurosci 2022; 58:325-353. [PMID: 35505057 DOI: 10.1007/7854_2022_355] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In this chapter we provide an overview of the pharmacological and circuit mechanisms that determine the willingness to expend effort in pursuit of rewards. A particular focus will be on the role of the mesolimbic dopamine system, as well the contributing roles of limbic and cortical brains areas involved in the evaluation, selection, and invigoration of goal-directed actions. We begin with a review of preclinical studies, which have provided key insights into the brain systems that are necessary and sufficient for effort-based decision-making and have characterized novel compounds that enhance selection of high-effort activities. Next, we summarize translational studies identifying and expanding this circuitry in humans. Finally, we discuss the relevance of this work for understanding common motivational impairments as part of the broader anhedonia symptom domain associated with mental illness, and the identification of new treatment targets within this circuitry to improve motivation and effort-expenditure.
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Affiliation(s)
| | - John D Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, USA
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9
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Sharp JL, Smith MA. The Effects of Drugs on Behavior Maintained by Social Contact: Role of Monoamines in Social Reinforcement. Front Behav Neurosci 2022; 15:805139. [PMID: 35264935 PMCID: PMC8899311 DOI: 10.3389/fnbeh.2021.805139] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/27/2021] [Indexed: 11/13/2022] Open
Abstract
Drug use is highly concordant among members of adolescent and young adult peer groups. One potential explanation for this observation is that drugs may increase the reinforcing effects of social contact, leading to greater motivation to establish and maintain contact with other members of the peer group. Several classes of drugs, particularly drugs that increase synaptic dopamine, increase the reinforcing effects of contextual stimuli, but the extent to which these drugs enhance the reinforcing effects of social contact is not known. The purpose of this study was to determine the extent to which drugs that increase synaptic dopamine, norepinephrine, and serotonin enhance the positive reinforcing effects of social contact. To this end, male and female Long-Evans rats were pretreated with acute doses of the selective dopamine reuptake inhibitor, WIN-35,428, the selective norepinephrine reuptake inhibitor, atomoxetine, the selective serotonin reuptake inhibitor, fluoxetine, the non-selective monoamine reuptake inhibitor, cocaine, and the non-selective monoamine releasers d-amphetamine and (±)-MDMA. Ten minutes later, the positive reinforcing effects of 30-s access to a same-sex social partner was examined on a progressive ratio schedule of reinforcement. To determine whether the reinforcement-altering effects of these drugs were specific to the social stimulus, the reinforcing effects of a non-social stimulus (30-s access to an athletic sock of similar size and coloring as another rat) was determined in control subjects. WIN-35,428, d-amphetamine, and cocaine, but not atomoxetine, fluoxetine, or MDMA, dose-dependently increased breakpoints maintained by a social partner under conditions in which responding maintained by a non-social stimulus was not affected. These data indicate that increases in extracellular dopamine, but not extracellular norepinephrine or serotonin, increases the positive reinforcing effects of social contact in both male and female rats. These data also provide support for the hypothesis that some drugs with high abuse liability increase the motivation to establish and maintain contact with social peers.
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Hiranita T, Obeng S, Sharma A, Wilkerson JL, McCurdy CR, McMahon LR. In vitro and in vivo pharmacology of kratom. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2021; 93:35-76. [PMID: 35341571 DOI: 10.1016/bs.apha.2021.10.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Kratom products have been historically and anecdotally used in south Asian countries for centuries to manage pain and opioid withdrawal. The use of kratom products has dramatically increased in the United States. More than 45 kratom alkaloids have been isolated, yet the overall pharmacology of the individual alkaloids is still not well characterized. The purpose of this chapter is to summarize in vitro and in vivo opioid activities of the primary kratom alkaloid mitragynine and its more potent metabolite 7-hydroxymitragynine. Following are experimental procedures described to characterize opioid receptor activity; receptor binding and functional assays, antinociceptive assays, operant conditioning assays, and respiratory plethysmography. The capacity of kratom alkaloids to confer tolerance and physical dependence as well as their pharmacokinetic properties are also summarized. The data reviewed here suggest that kratom products and mitragynine possess low efficacy agonist activity at the mu-opioid receptor in vivo. In addition, kratom products and mitragynine have been demonstrated to antagonize the effects of high efficacy mu-opioid agonists. The data further suggest that 7-hydroxymitragynine formed in vivo by metabolism of mitragynine may be minimally involved in the overall behavioral profile of mitragynine and kratom, whereas 7-hydroxymitragynine itself, at sufficiently high doses administered exogenously, shares many of the same abuse- and dependence-related behavioral effects associated with traditional opioid agonists. The apparent low efficacy of kratom products and mitragynine at mu-opioid receptors supports the development of these ligands as effective and potentially safe medications for opioid use disorder.
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Affiliation(s)
- Takato Hiranita
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, United States
| | - Samuel Obeng
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, United States; Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL, United States
| | - Abhisheak Sharma
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL, United States; Translational Drug Development Core, Clinical and Translational Sciences Institute, College of Pharmacy, University of Florida, Gainesville, FL, United States
| | - Jenny L Wilkerson
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, United States
| | - Christopher R McCurdy
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL, United States; Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, FL, United States; Translational Drug Development Core, Clinical and Translational Sciences Institute, College of Pharmacy, University of Florida, Gainesville, FL, United States
| | - Lance R McMahon
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, United States.
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11
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Hersey M, Bacon AK, Bailey LG, Coggiano MA, Newman AH, Leggio L, Tanda G. Psychostimulant Use Disorder, an Unmet Therapeutic Goal: Can Modafinil Narrow the Gap? Front Neurosci 2021; 15:656475. [PMID: 34121988 PMCID: PMC8187604 DOI: 10.3389/fnins.2021.656475] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/20/2021] [Indexed: 12/11/2022] Open
Abstract
The number of individuals affected by psychostimulant use disorder (PSUD) has increased rapidly over the last few decades resulting in economic, emotional, and physical burdens on our society. Further compounding this issue is the current lack of clinically approved medications to treat this disorder. The dopamine transporter (DAT) is a common target of psychostimulant actions related to their use and dependence, and the recent availability of atypical DAT inhibitors as a potential therapeutic option has garnered popularity in this research field. Modafinil (MOD), which is approved for clinical use for the treatment of narcolepsy and sleep disorders, blocks DAT just like commonly abused psychostimulants. However, preclinical and clinical studies have shown that it lacks the addictive properties (in both behavioral and neurochemical studies) associated with other abused DAT inhibitors. Clinical availability of MOD has facilitated its off-label use for several psychiatric disorders related to alteration of brain dopamine (DA) systems, including PSUD. In this review, we highlight clinical and preclinical research on MOD and its R-enantiomer, R-MOD, as potential medications for PSUD. Given the complexity of PSUD, we have also reported the effects of MOD on psychostimulant-induced appearance of several symptoms that could intensify the severity of the disease (i.e., sleep disorders and impairment of cognitive functions), besides the potential therapeutic effects of MOD on PSUD.
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Affiliation(s)
- Melinda Hersey
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
| | - Amanda K. Bacon
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
| | - Lydia G. Bailey
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
| | - Mark A. Coggiano
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
| | - Amy H. Newman
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
| | - Lorenzo Leggio
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
- Clinical Psychoneuroendo- crinology and Neuropsychopharmacology Section, Translational Addiction Medicine Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
- National Institute on Alcohol Abuse and Alcoholism, Division of Intramural Clinical and Biological Research, National Institutes of Health, Bethesda, MD, United States
| | - Gianluigi Tanda
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, United States
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12
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Newman AH, Ku T, Jordan CJ, Bonifazi A, Xi ZX. New Drugs, Old Targets: Tweaking the Dopamine System to Treat Psychostimulant Use Disorders. Annu Rev Pharmacol Toxicol 2021; 61:609-628. [PMID: 33411583 DOI: 10.1146/annurev-pharmtox-030220-124205] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The abuse of illicit psychostimulants such as cocaine and methamphetamine continues to pose significant health and societal challenges. Despite considerable efforts to develop medications to treat psychostimulant use disorders, none have proven effective, leaving an underserved patient population and unanswered questions about what mechanism(s) of action should be targeted for developing pharmacotherapies. As both cocaine and methamphetamine rapidly increase dopamine (DA) levels in mesolimbic brain regions, leading to euphoria that in some can lead to addiction, targets in which this increased dopaminergic tone may be mitigated have been explored. Further, understanding and targeting mechanisms underlying relapse are fundamental to the success of discovering medications that reduce the reinforcing effects of the drug of abuse, decrease the negative reinforcement or withdrawal/negative affect that occurs during abstinence, or both. Atypical inhibitors of the DA transporter and partial agonists/antagonists at DA D3 receptors are described as two promising targets for future drug development.
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Affiliation(s)
- Amy Hauck Newman
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA;
| | - Therese Ku
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA;
| | - Chloe J Jordan
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA;
| | - Alessandro Bonifazi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA;
| | - Zheng-Xiong Xi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, Maryland 21224, USA;
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13
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Cabé J, Brousse G, Pereira B, Cabé N, Karsinti E, Zerdazi EH, Icick R, Llorca PM, Bloch V, Vorspan F, De Chazeron I. Influence of Clinical Markers of Dopaminergic Behaviors on Depressive Symptoms During Withdrawal in Cocaine Users. Front Psychiatry 2021; 12:775670. [PMID: 34880796 PMCID: PMC8645893 DOI: 10.3389/fpsyt.2021.775670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 10/29/2021] [Indexed: 12/04/2022] Open
Abstract
Background: During cocaine withdrawal, transient depressive symptoms that do not meet the criteria for depression, but promote relapse, are frequently observed. Their temporality could evoke a role of dopamine, especially since the underlying mechanism of these depressive symptoms is not well understood. We hypothesized that variation in the dopaminergic activity profile, modeled from clinical markers, could be implicated in the development of depressive symptoms during cocaine withdrawal. Methods: We compared patients reporting depressive symptoms (RDS+) or not (RDS-) during cocaine withdrawal. We evaluated dopaminergic activity through indirect clinical markers based on the known dopaminergic behaviors. A combined criterion was constructed for hyper and hypo dopaminergic models according to the O'Brien method and illustrated by the Hedges' effect-size and forest-plot graph. A multidimensional factorial analysis was carried out to determine which parameters discriminate RDS+/RDS- patients. Results: 313 patients were included, and 77% reported depressive symptoms during cocaine withdrawal. Hyperdopaminergic variables used to discriminate the two groups had a large overall effect size (-0.669) and included psychotic symptoms (-0.524), hallucinations (-0.548), and delusions (-0.528). The overall effect of the hypodopaminergic component was considerable (-0.604) with a large effect size for the severity of dependence (-0.616), withdrawal symptoms (-0.578), and anhedonia (-0.528). The combined model including hyperdopaminergic and hypodopaminergic components had the largest effect size (-0.785). Conclusion: The dopaminergic activities profile, assessed by indirect clinical markers, seems to characterize patients with depressive symptoms very well during cocaine withdrawal. RDS+ patients reported moreover higher levels of psychotic symptoms and more severe cocaine use disorder than RDS-.
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Affiliation(s)
- Julien Cabé
- Service d'addictologie et pathologies duelles, Centre Hospitalier Universitaire de Clermont-Ferrand, Clermont-Ferrand, France.,Université Clermont Auvergne, CHU, CNRS, Clermont Auvergne INP, Institut Pascal, Clermont-Ferrand, France.,Faculté de Médecine, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Georges Brousse
- Service d'addictologie et pathologies duelles, Centre Hospitalier Universitaire de Clermont-Ferrand, Clermont-Ferrand, France.,Université Clermont Auvergne, CHU, CNRS, Clermont Auvergne INP, Institut Pascal, Clermont-Ferrand, France.,Faculté de Médecine, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Bruno Pereira
- Direction de la Recherche Clinique et des Innovations, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Nicolas Cabé
- Normandie University, UNICAEN, PSL Université de Paris, EPHE, INSERM, U1077, CHU de Caen, GIP Cyceron, Neuropsychologie et Imagerie de la Mémoire Humaine, Caen, France.,Service d'Addictologie, Centre Hospitalier Universitaire de Caen, Caen, France
| | - Emily Karsinti
- INSERM UMR-S 1144, Université de Paris, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Psychiatrie et de Médecine Addictologique, Hôpital Fernand Widal, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - El-Hadi Zerdazi
- INSERM UMR-S 1144, Université de Paris, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Psychiatrie et de Médecine Addictologique, Hôpital Fernand Widal, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Romain Icick
- INSERM UMR-S 1144, Université de Paris, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Psychiatrie et de Médecine Addictologique, Hôpital Fernand Widal, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Pierre M Llorca
- Université Clermont Auvergne, CHU, CNRS, Clermont Auvergne INP, Institut Pascal, Clermont-Ferrand, France.,Faculté de Médecine, Université Clermont Auvergne, Clermont-Ferrand, France.,Service de Psychiatrie B, Centre Hospitalier Universitaire de Clermont-Ferrand, Clermont-Ferrand, France
| | - Vanessa Bloch
- INSERM UMR-S 1144, Université de Paris, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Psychiatrie et de Médecine Addictologique, Hôpital Fernand Widal, Assistance Publique-Hôpitaux de Paris, Paris, France.,Faculté de Médecine, Université de Paris, Paris, France
| | - Florence Vorspan
- INSERM UMR-S 1144, Université de Paris, Optimisation Thérapeutique en Neuropsychopharmacologie, Paris, France.,Département de Psychiatrie et de Médecine Addictologique, Hôpital Fernand Widal, Assistance Publique-Hôpitaux de Paris, Paris, France.,Faculté de Médecine, Université de Paris, Paris, France
| | - Ingrid De Chazeron
- Service d'addictologie et pathologies duelles, Centre Hospitalier Universitaire de Clermont-Ferrand, Clermont-Ferrand, France.,Université Clermont Auvergne, CHU, CNRS, Clermont Auvergne INP, Institut Pascal, Clermont-Ferrand, France.,Faculté de Médecine, Université Clermont Auvergne, Clermont-Ferrand, France
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14
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Soto PL, Hiranita T. Effects of benztropine analogs on delay discounting in rats. Psychopharmacology (Berl) 2020; 237:3783-3794. [PMID: 32964243 PMCID: PMC7686108 DOI: 10.1007/s00213-020-05655-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Accepted: 08/31/2020] [Indexed: 10/23/2022]
Abstract
RATIONALE Methylphenidate and d-amphetamine, medications used for treatment of attention deficit hyperactivity disorder (ADHD), are used recreationally and self-administered by laboratory animals. Benztropine (BZT) analogs, like those medications, increase synaptic dopamine levels but are less effective in maintaining self-administration, suggesting clinical utility with less abuse liability. OBJECTIVES The current study was designed to evaluate potential therapeutic effects of BZT analogs related to ADHD. METHODS Rats responded under a delay-discounting procedure in which responses on one lever produced immediate delivery of a single food pellet and alternative responses produced four food pellets either immediately or with various temporal delays, with those delays arranged in ascending or random orders in different groups of rats. Selection of the smaller more immediate reinforcer has been suggested as an aspect of "impulsivity," a trait with suggested involvement in ADHD. Other rats were studied under fixed-interval (FI) 300-s schedules to assess drug effects on behavior under temporal control. RESULTS d-Amphetamine, methylphenidate, and the BZT analog AHN 1-055, but not AHN 2-005 or JHW 007, increased selection of the large, delayed reinforcer with either arrangement of delays. All drugs changed the temporal distribution of responses within the FI from one with responses concentrated at the end to a more uniform distribution. Changes in the temporal distribution of FI responding occurred with drugs that did not affect discounting suggesting that discounting does not arise directly from the same temporal control processes controlling FI responding. CONCLUSIONS AHN 1-055 may be of clinical utility in the treatment of ADHD.
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Affiliation(s)
- Paul L Soto
- Department of Psychology, Louisiana State University, Baton Rouge, LA, 70803, USA.
| | - Takato Hiranita
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL, USA
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15
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Rotolo RA, Presby RE, Tracy O, Asar S, Yang JH, Correa M, Murray F, Salamone JD. The novel atypical dopamine transport inhibitor CT-005404 has pro-motivational effects in neurochemical and inflammatory models of effort-based dysfunctions related to psychopathology. Neuropharmacology 2020; 183:108325. [PMID: 32956676 DOI: 10.1016/j.neuropharm.2020.108325] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/11/2020] [Accepted: 09/15/2020] [Indexed: 01/23/2023]
Abstract
Depressed individuals suffer from effort-related motivational symptoms such as anergia and fatigue, which are resistant to treatment with many common antidepressants. While drugs that block dopamine transport (DAT) reportedly have positive motivational effects, DAT inhibitors such as cocaine and amphetamines produce undesirable side effects. Thus, there is a need to develop and characterize novel atypical DAT inhibitors with unique and selective binding profiles. Rodent effort-based choice tasks provide useful models of motivational dysfunctions. With these tasks, animals choose between a high-effort instrumental action leading to highly valued reinforcement vs. a low effort/low reward option. The present studies focused on the initial characterization of a novel atypical DAT inhibitor, CT-005404, which binds to DAT with high selectivity relative to serotonin and norepinephrine transport, and produces long-term elevations of extracellular DA. CT-005404 was assessed for its ability to attenuate the effort-related motivational effects of the DA depleting agent tetrabenazine and the pro-inflammatory cytokine interleukin-1β (IL-1β) using a fixed ratio 5/chow feeding choice test. Tetrabenazine (1.0 mg/kg i.p.) shifted choice behavior, decreasing lever pressing and increasing chow intake. IL-1β (4.0 μg/kg i.p.) also decreased lever pressing. CT-005404 was co-administered (7.5-30.0 mg/kg p.o.) with either tetrabenazine or IL-1β, and the 15.0 and 30.0 mg/kg doses significantly reversed the effects of tetrabenazine and IL-1β. CT-005404 administered alone produced a dose-related increase in lever pressing in rats tested on a progressive ratio/chow feeding choice task. Atypical DAT inhibitors such as CT-005404 offer potential as a new avenue for drug treatment of motivational dysfunctions in humans.
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Affiliation(s)
- Renee A Rotolo
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Rose E Presby
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Olivia Tracy
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Sokaina Asar
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Jen-Hau Yang
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06261-1020, USA
| | - Merce Correa
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06261-1020, USA; Àrea de Psicobiologia, Campus de Riu Sec, Universitat Jaume I, 12071, Castelló, Spain
| | - Fraser Murray
- Chronos Therapeutics, The Magdalen Centre, Oxford Science Park, Oxford, OX4 4GA, UK
| | - John D Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, 06261-1020, USA.
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16
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Tanda G, Hersey M, Hempel B, Xi ZX, Newman AH. Modafinil and its structural analogs as atypical dopamine uptake inhibitors and potential medications for psychostimulant use disorder. Curr Opin Pharmacol 2020; 56:13-21. [PMID: 32927246 DOI: 10.1016/j.coph.2020.07.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/17/2020] [Accepted: 07/20/2020] [Indexed: 12/20/2022]
Abstract
Pharmacotherapeutics for treatment of psychostimulant use disorder are still an unmet medical goal. Recently, off label use of modafinil (MOD), an approved medication for treatment of sleep disturbances, has been tested as a therapeutic for cocaine and methamphetamine use disorder. Positive results have been found in subjects dependent on psychostimulants without concurrent abuse of other substances. Novel structural analogs of MOD have been synthesized in the search for compounds with potentially broader therapeutic efficacy than the parent drug. In the present report we review their potential efficacy as treatments for psychostimulant abuse and dependence assessed in preclinical tests. Results from these preclinical proof of concept studies reveal that some modafinil analogs do not possess typical cocaine-like neurochemical and behavioral effects. Further, they might blunt the reinforcing effects of psychostimulants in animal models, suggesting their potential efficacy as pharmacotherapeutics for treatment of psychostimulant use disorders.
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Affiliation(s)
- Gianluigi Tanda
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA.
| | - Melinda Hersey
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Briana Hempel
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Zheng-Xiong Xi
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Amy Hauck Newman
- Medication Development Program, Molecular Targets and Medication Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, NIH, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
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17
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Modafinil potentiates cocaine self-administration by a dopamine-independent mechanism: possible involvement of gap junctions. Neuropsychopharmacology 2020; 45:1518-1526. [PMID: 32340023 PMCID: PMC7360549 DOI: 10.1038/s41386-020-0680-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 03/15/2020] [Accepted: 04/09/2020] [Indexed: 12/21/2022]
Abstract
Modafinil and methylphenidate are medications that inhibit the neuronal reuptake of dopamine, a mechanism shared with cocaine. Their use as "smart drugs" by healthy subjects poses health concerns and requires investigation. We show that methylphenidate, but not modafinil, maintained intravenous self-administration in Sprague-Dawley rats similar to cocaine. Both modafinil and methylphenidate pretreatments potentiated cocaine self-administration. Cocaine, at self-administered doses, stimulated mesolimbic dopamine levels. This effect was potentiated by methylphenidate, but not by modafinil pretreatments, indicating dopamine-dependent actions for methylphenidate, but not modafinil. Modafinil is known to facilitate electrotonic neuronal coupling by actions on gap junctions. Carbenoxolone, a gap junction inhibitor, antagonized modafinil, but not methylphenidate potentiation of cocaine self-administration. Our results indicate that modafinil shares mechanisms with cocaine and methylphenidate but has a unique pharmacological profile that includes facilitation of electrotonic coupling and lower abuse liability, which may be exploited in future therapeutic drug design for cocaine use disorder.
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18
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Lee MR, Rohn MC, Zanettini C, Coggiano MA, Leggio L, Tanda G. Effect of systemically administered oxytocin on dose response for methylphenidate self-administration and mesolimbic dopamine levels. Ann N Y Acad Sci 2019; 1455:173-184. [PMID: 31074517 PMCID: PMC10014164 DOI: 10.1111/nyas.14101] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/01/2019] [Accepted: 03/27/2019] [Indexed: 11/29/2022]
Abstract
The neuropeptide oxytocin (OT) alters behaviors related to the administration of drugs of abuse, including stimulants. OT also plays a key role in social bonding, which involves an interaction between OT and dopamine (DA) in the nucleus accumbens (NAc). The nature of the interaction between OT and DA in the striatum in the context of psychostimulants is unclear. We investigated the effect of OT, delivered intraperitoneally, on the methylphenidate (MP) dose-response function for self-administration in rats. Food was used as a control condition. In a microdialysis study, we measured the effect of intraperitoneal OT on MP-stimulated striatal DA levels. Systemic OT pretreatment caused a downward shift in the MP dose-response function for self-administration, while having no effect on motor activity. OT also caused a reduction in food self-administration, although a significantly higher dose of OT was required for this effect compared with that required for a reduction of MP self-administration. Systemic OT pretreatment caused a potentiation of MP-stimulated DA levels in the NAc shell but not in the core. The significance of these findings is discussed, including the potential of OT as a therapeutic agent for addictive disorders.
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Affiliation(s)
- Mary R. Lee
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Basic Research and National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Bethesda, MD
| | - Matthew C.H. Rohn
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Basic Research and National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Bethesda, MD
| | - Claudio Zanettini
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
| | - Mark A. Coggiano
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
| | - Lorenzo Leggio
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Basic Research and National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Bethesda, MD
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
- Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University, Providence, RI
| | - Gianluigi Tanda
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
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19
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Newman AH, Cao J, Keighron JD, Jordan CJ, Bi GH, Liang Y, Abramyan AM, Avelar AJ, Tschumi CW, Beckstead MJ, Shi L, Tanda G, Xi ZX. Translating the atypical dopamine uptake inhibitor hypothesis toward therapeutics for treatment of psychostimulant use disorders. Neuropsychopharmacology 2019; 44:1435-1444. [PMID: 30858517 PMCID: PMC6785152 DOI: 10.1038/s41386-019-0366-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/27/2019] [Accepted: 02/27/2019] [Indexed: 11/10/2022]
Abstract
Medication-assisted treatments are unavailable to patients with cocaine use disorders. Efforts to develop potential pharmacotherapies have led to the identification of a promising lead molecule, JJC8-091, that demonstrates a novel binding mode at the dopamine transporter (DAT). Here, JJC8-091 and a structural analogue, JJC8-088, were extensively and comparatively assessed to elucidate neurochemical correlates to their divergent behavioral profiles. Despite sharing significant structural similarity, JJC8-088 was more cocaine-like, increasing extracellular DA concentrations in the nucleus accumbens shell (NAS) efficaciously and more potently than JJC8-091. In contrast, JJC8-091 was not self-administered and was effective in blocking cocaine-induced reinstatement to drug seeking. Electrophysiology experiments confirmed that JJC8-091 was more effective than JJC8-088 at inhibiting cocaine-mediated enhancement of DA neurotransmission. Further, when VTA DA neurons in DAT-cre mice were optically stimulated, JJC8-088 produced a significant leftward shift in the stimulation-response curve, similar to cocaine, while JJC8-091 shifted the curve downward, suggesting attenuation of DA-mediated brain reward. Computational models predicted that JJC8-088 binds in an outward facing conformation of DAT, similar to cocaine. Conversely, JJC8-091 steers DAT towards a more occluded conformation. Collectively, these data reveal the underlying molecular mechanism at DAT that may be leveraged to rationally optimize leads for the treatment of cocaine use disorders, with JJC8-091 representing a compelling candidate for development.
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Affiliation(s)
- Amy Hauck Newman
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD, 21224, USA.
| | - Jianjing Cao
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Jacqueline D. Keighron
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Chloe J. Jordan
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Guo-Hua Bi
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Ying Liang
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Ara M. Abramyan
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Alicia J. Avelar
- 0000 0001 0629 5880grid.267309.9Department of Cellular and Integrative Physiology, UT Health Science Center, San Antonio, TX USA
| | - Christopher W. Tschumi
- 0000 0001 0629 5880grid.267309.9Department of Cellular and Integrative Physiology, UT Health Science Center, San Antonio, TX USA ,0000 0000 8527 6890grid.274264.1Aging & Metabolism Research Group, Oklahoma Medical Research Foundation, Oklahoma City, OK USA
| | - Michael J. Beckstead
- 0000 0001 0629 5880grid.267309.9Department of Cellular and Integrative Physiology, UT Health Science Center, San Antonio, TX USA ,0000 0000 8527 6890grid.274264.1Aging & Metabolism Research Group, Oklahoma Medical Research Foundation, Oklahoma City, OK USA
| | - Lei Shi
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Gianluigi Tanda
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
| | - Zheng-Xiong Xi
- 0000 0004 1936 8075grid.48336.3aMolecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD 21224 USA
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20
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Rotolo RA, Dragacevic V, Kalaba P, Urban E, Zehl M, Roller A, Wackerlig J, Langer T, Pistis M, De Luca MA, Caria F, Schwartz R, Presby RE, Yang JH, Samels S, Correa M, Lubec G, Salamone JD. The Novel Atypical Dopamine Uptake Inhibitor (S)-CE-123 Partially Reverses the Effort-Related Effects of the Dopamine Depleting Agent Tetrabenazine and Increases Progressive Ratio Responding. Front Pharmacol 2019; 10:682. [PMID: 31316379 PMCID: PMC6611521 DOI: 10.3389/fphar.2019.00682] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 05/27/2019] [Indexed: 12/21/2022] Open
Abstract
Animal studies of effort-based choice behavior are being used to model effort-related motivational dysfunctions in humans. With these procedures, animals are offered a choice between high-effort instrumental actions leading to highly valued reinforcers vs. low effort/low reward options. Several previous studies have shown that dopamine (DA) uptake inhibitors, including GBR12909, lisdexamfetamine, methylphenidate, and PRX-14040, can reverse the effort-related effects of the vesicular monoamine transport blocker tetrabenazine, which inhibits DA storage. Because many drugs that block DA transport act as major stimulants that also release DA, and produce a number of undesirable side effects, there is a need to develop and characterize novel atypical DA transport inhibitors. (S)-CE-123 ((S)-5-((benzhydrylsulfinyl) methyl)thiazole) is a recently developed analog of modafinil with the biochemical characteristics of an atypical DA transport blocker. The present paper describes the enantioselective synthesis and initial chemical characterization of (S)-CE-123, as well as behavioral experiments involving effort-based choice and microdialysis studies of extracellular DA. Rats were assessed using the fixed ratio 5/chow feeding choice test. Tetrabenazine (1.0 mg/kg) shifted choice behavior, decreasing lever pressing and increasing chow intake. (S)-CE-123 was coadministered at doses ranging from 6.0 to 24.0 mg/kg, and the highest dose partially but significantly reversed the effects of tetrabenazine, although this dose had no effect on fixed ratio responding when administered alone. Additional experiments showed that (S)-CE-123 significantly increased lever pressing on a progressive ratio/chow feeding choice task and that the effective dose (24.0 mg/kg) increased extracellular DA in nucleus accumbens core. In summary, (S)-CE-123 has the behavioral and neurochemical profile of a compound that can block DA transport, reverse the effort-related effects of tetrabenazine, and increase selection of high-effort progressive ratio responding. This suggests that (S)-CE-123 or a similar compound could be useful as a treatment for effort-related motivational dysfunction in humans.
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Affiliation(s)
- Renee A Rotolo
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Vladimir Dragacevic
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Predrag Kalaba
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Ernst Urban
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Martin Zehl
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Alexander Roller
- X-ray Structure Analysis Centre, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Judith Wackerlig
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Thierry Langer
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Marco Pistis
- Department of Biomedical Sciences, University of Cagliari, National Institute of Neuroscience (INN), Cagliari, Italy
| | - Maria Antonietta De Luca
- Department of Biomedical Sciences, University of Cagliari, National Institute of Neuroscience (INN), Cagliari, Italy
| | - Francesca Caria
- Department of Biomedical Sciences, University of Cagliari, National Institute of Neuroscience (INN), Cagliari, Italy
| | - Rebecca Schwartz
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Rose E Presby
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Jen-Hau Yang
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Shanna Samels
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
| | - Merce Correa
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States.,Àrea de Psicobiologia, Universitat Jaume I, Castelló, Spain
| | - Gert Lubec
- Department of Neuroproteomics, Paracelsus Medical University, Salzburg, Austria
| | - John D Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, CT, United States
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21
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Keighron JD, Quarterman JC, Cao J, DeMarco EM, Coggiano MA, Gleaves A, Slack RD, Zanettini C, Newman AH, Tanda G. Effects of ( R)-Modafinil and Modafinil Analogues on Dopamine Dynamics Assessed by Voltammetry and Microdialysis in the Mouse Nucleus Accumbens Shell. ACS Chem Neurosci 2019; 10:2012-2021. [PMID: 30645944 DOI: 10.1021/acschemneuro.8b00340] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Recent discoveries have improved our understanding of the physiological and pathological roles of the dopamine transporter (DAT); however, only a few drugs are clinically available for DAT-implicated disorders. Among those drugs, modafinil (MOD) and its ( R)-enantiomer (R-MOD) have been used off-label as therapies for psychostimulant use disorders, but they have shown limited effectiveness in clinical trials. Recent preclinical studies on MOD and R-MOD have led to chemically modified structures aimed toward improving their neurobiological properties that might lead to more effective therapeutics for stimulant use disorders. This study examines three MOD analogues (JJC8-016, JJC8-088, and JJC8-091) with improved DAT affinities compared to their parent compound. These compounds were investigated for their effects on the neurochemistry (brain microdialysis and FSCV) and behavior (ambulatory activity) of male Swiss-Webster mice. Our data indicate that these compounds have dissimilar effects on tonic and phasic dopamine in the nucleus accumbens shell and variability in producing ambulatory activity. These results suggest that small changes in the chemical structure of a DAT inhibitor can cause compounds such as JJC8-088 to produce effects similar to abused psychostimulants like cocaine. In contrast, other compounds like JJC8-091 do not share cocaine-like effects and have a more atypical DAT-inhibitor profile, which may prove to be an advancement in the treatment of psychostimulant use disorders.
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Zanettini C, Scaglione A, Keighron JD, Giancola JB, Lin SC, Newman AH, Tanda G. Pharmacological classification of centrally acting drugs using EEG in freely moving rats: an old tool to identify new atypical dopamine uptake inhibitors. Neuropharmacology 2018; 161:107446. [PMID: 30481526 DOI: 10.1016/j.neuropharm.2018.11.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 11/05/2018] [Accepted: 11/23/2018] [Indexed: 10/27/2022]
Abstract
Atypical dopamine uptake inhibitors (DUIs) bind to the dopamine transporter and inhibit the reuptake of dopamine but have lower abuse potential than psychostimulants. Several atypical DUIs can block abuse-related effects of cocaine and methamphetamine, thus making them potential medication candidates for psychostimulant use disorders. The aim of the current study is to establish an in-vivo assay using EEG for the rapid identification of atypical DUIs with potential for medication development. The typical DUIs cocaine and methylphenidate dose-dependently decreased the power of the alpha, beta, and gamma bands. The atypical DUI modafinil and its F-analog, JBG1-049, decreased the power of beta, but in contrast to cocaine, none of the other frequency bands, while JHW007 did not significantly alter the EEG spectrum. The mu-opioid receptor agonists heroin and morphine dose-dependently decreased the power of gamma and increased power of the other bands. The effect of morphine on EEG power bands was antagonized by naltrexone. The NMDA receptor antagonist ketamine increased the power of all frequency bands. Therefore, typical and atypical DUIs and drugs of other classes differentially affected EEG spectra, showing distinctive features in the magnitude and direction of their effects on EEG. Comparative analysis of the effects of test drugs on EEG indicates a potential atypical profile of JBG1-049 with similar potency and effectiveness to its parent compound modafinil. These data suggest that EEG can be used to rapidly screen compounds for potential activity at specific pharmacological targets and provide valuable information for guiding the early stages of drug development. This article is part of the issue entitled 'Special Issue on Neurotransmitter Transporters'.
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Affiliation(s)
- Claudio Zanettini
- Medication Development Program, Molecular Targets and Medications Discovery Branch, NIDA-IRP, NIH/DHHS, Baltimore, MD, USA.
| | - Alessandro Scaglione
- Neural Circuits and Cognition Unit, Laboratory of Behavioral Neuroscience, NIA-IRP, NIH/DHHS, Baltimore, MD, USA
| | - Jacqueline D Keighron
- Medication Development Program, Molecular Targets and Medications Discovery Branch, NIDA-IRP, NIH/DHHS, Baltimore, MD, USA
| | - JoLynn B Giancola
- Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, NIDA-IRP, NIH/DHHS, Baltimore, MD, USA
| | - Shih-Chieh Lin
- Neural Circuits and Cognition Unit, Laboratory of Behavioral Neuroscience, NIA-IRP, NIH/DHHS, Baltimore, MD, USA
| | - Amy H Newman
- Medication Development Program, Molecular Targets and Medications Discovery Branch, NIDA-IRP, NIH/DHHS, Baltimore, MD, USA; Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, NIDA-IRP, NIH/DHHS, Baltimore, MD, USA
| | - Gianluigi Tanda
- Medication Development Program, Molecular Targets and Medications Discovery Branch, NIDA-IRP, NIH/DHHS, Baltimore, MD, USA
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23
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Tomlinson MJ, Krout D, Pramod AB, Lever JR, Newman AH, Henry LK, Vaughan RA. Identification of the benztropine analog [ 125I]GA II 34 binding site on the human dopamine transporter. Neurochem Int 2018; 123:34-45. [PMID: 30125594 DOI: 10.1016/j.neuint.2018.08.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/10/2018] [Accepted: 08/14/2018] [Indexed: 12/21/2022]
Abstract
The dopamine transporter (DAT) is a neuronal membrane protein that is responsible for reuptake of dopamine (DA) from the synapse and functions as a major determinant in control of DA neurotransmission. Cocaine and many psychostimulant drugs bind to DAT and block reuptake, inducing DA overflow that forms the neurochemical basis for euphoria and addiction. Paradoxically, however, some ligands such as benztropine (BZT) bind to DAT and inhibit reuptake but do not produce these effects, and it has been hypothesized that differential mechanisms of binding may stabilize specific transporter conformations that affect downstream neurochemical or behavioral outcomes. To investigate the binding mechanisms of BZT on DAT we used the photoaffinity BZT analog [125I]N-[n-butyl-4-(4‴-azido-3‴-iodophenyl)]-4',4″-difluoro-3α-(diphenylmethoxy)tropane ([125I]GA II 34) to identify the site of cross-linking and predict the binding pose relative to that of previously-examined cocaine photoaffinity analogs. Biochemical findings show that adduction of [125I]GA II 34 occurs at residues Asp79 or Leu80 in TM1, with molecular modeling supporting adduction to Leu80 and a pharmacophore pose in the central S1 site similar to that of cocaine and cocaine analogs. Substituted cysteine accessibility method protection analyses verified these findings, but identified some differences in structural stabilization relative to cocaine that may relate to BZT neurochemical outcomes.
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Affiliation(s)
- Michael J Tomlinson
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, 1301 North Columbia Road, Grand Forks, ND 58202, United States
| | - Danielle Krout
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, 1301 North Columbia Road, Grand Forks, ND 58202, United States
| | - Akula Bala Pramod
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, 1301 North Columbia Road, Grand Forks, ND 58202, United States
| | - John R Lever
- Research Service, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, 65201, United States; Department of Radiology and Radiopharmaceutical Sciences Institute, University of Missouri, Columbia, MO 65211, United States
| | - Amy Hauck Newman
- Medicinal Chemistry Section, National Institute on Drug Abuse - Intramural Research Program, Baltimore, MD 21224, United States
| | - L Keith Henry
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, 1301 North Columbia Road, Grand Forks, ND 58202, United States.
| | - Roxanne A Vaughan
- Department of Biomedical Sciences, University of North Dakota School of Medicine and Health Sciences, 1301 North Columbia Road, Grand Forks, ND 58202, United States.
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24
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Hong WC, Wasko MJ, Wilkinson DS, Hiranita T, Li L, Hayashi S, Snell DB, Madura JD, Surratt CK, Katz JL. Dopamine Transporter Dynamics of N-Substituted Benztropine Analogs with Atypical Behavioral Effects. J Pharmacol Exp Ther 2018; 366:527-540. [PMID: 29945932 DOI: 10.1124/jpet.118.250498] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 06/22/2018] [Indexed: 01/07/2023] Open
Abstract
Atypical dopamine transporter (DAT) inhibitors, despite high DAT affinity, do not produce the psychomotor stimulant and abuse profile of standard DAT inhibitors such as cocaine. Proposed contributing features for those differences include off-target actions, slow onsets of action, and ligand bias regarding DAT conformation. Several 3α-(4',4''-difluoro-diphenylmethoxy)tropanes were examined, including those with the following substitutions: N-(indole-3''-ethyl)- (GA1-69), N-(R)-2''-amino-3''-methyl-n-butyl- (GA2-50), N-2''aminoethyl- (GA2-99), and N-(cyclopropylmethyl)- (JHW013). These compounds were previously reported to have rapid onset of behavioral effects and were presently evaluated pharmacologically alone or in combination with cocaine. DAT conformational mode was assessed by substituted-cysteine accessibility and molecular dynamics (MD) simulations. As determined by substituted-cysteine alkylation, all BZT analogs except GA2-99 showed bias for a cytoplasmic-facing DAT conformation, whereas cocaine stabilized the extracellular-facing conformation. MD simulations suggested that several analog-DAT complexes formed stable R85-D476 "outer gate" bonds that close the DAT to extracellular space. GA2-99 diverged from this pattern, yet had effects similar to those of other atypical DAT inhibitors. Apparent DAT association rates of the BZT analogs in vivo were slower than that for cocaine. None of the compounds was self-administered or stimulated locomotion, and each blocked those effects of cocaine. The present findings provide more detail on ligand-induced DAT conformations and indicate that aspects of DAT conformation other than "open" versus "closed" may facilitate predictions of the actions of DAT inhibitors and may promote rational design of potential treatments for psychomotor-stimulant abuse.
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Affiliation(s)
- Weimin C Hong
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Michael J Wasko
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Derek S Wilkinson
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Takato Hiranita
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Libin Li
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Shuichiro Hayashi
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - David B Snell
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Jeffry D Madura
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Christopher K Surratt
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
| | - Jonathan L Katz
- Department of Pharmaceutical Sciences, Butler University, Indianapolis, Indiana (W.C.H.); Division of Pharmaceutical Sciences (M.J.W., C.K.S.) and Department of Chemistry and Biochemistry (J.D.M.), Duquesne University, Pittsburgh; and Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland (D.S.W., T.H., L.L., S.H., D.B.S., J.L.K.)
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25
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Dassanayake AF, Canales JJ. Replacement treatment during extinction training with the atypical dopamine uptake inhibitor, JHW-007, reduces relapse to methamphetamine seeking. Neurosci Lett 2018; 671:88-92. [PMID: 29452175 DOI: 10.1016/j.neulet.2018.02.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 01/26/2018] [Accepted: 02/12/2018] [Indexed: 12/29/2022]
Abstract
There are currently no approved medications to effectively counteract the effects of methamphetamine (METH), reduce its abuse and prolong abstinence from it. Data accumulated in recent years have shown that a range of N-substituted benztropine (BZT) analogues possesses psychopharmacological features consistent with those of a potential replacement or "substitute" treatment for stimulant addiction. On the other hand, the evidence that antidepressant therapy may effectively prevent relapse to stimulant seeking is controversial. Here, we compared in rats the ability of the BZT analogue and high affinity dopamine (DA) reuptake inhibitor, JHW-007, and the antidepressant, trazodone, administered during extinction sessions after chronic METH self-administration, to alter METH-primed reinstatement of drug seeking. The data showed that trazodone produced paradoxical effects on lever pressing during extinction of METH self-administration, decreasing active, but increasing inactive, lever pressing. JHW-007 did not have any observable effects on extinction training. Importantly, JHW-007 significantly attenuated METH-primed reinstatement, whereas trazodone enhanced it. These findings lend support to the candidacy of selective DA uptake blockers, such as JHW-007, as potential treatments for METH addiction, but not to the use of antidepressant medication as a single therapeutic approach for relapse prevention.
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Affiliation(s)
- Ashlea F Dassanayake
- Division of Psychology, School of Medicine, University of Tasmania, Private Bag 30, Hobart, TAS, 7001, Australia
| | - Juan J Canales
- Division of Psychology, School of Medicine, University of Tasmania, Private Bag 30, Hobart, TAS, 7001, Australia.
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26
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Behavioral economic analysis of the effects of N-substituted benztropine analogs on cocaine self-administration in rats. Psychopharmacology (Berl) 2018; 235:47-58. [PMID: 28932889 DOI: 10.1007/s00213-017-4739-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 09/12/2017] [Indexed: 10/18/2022]
Abstract
RATIONALE AND OBJECTIVES Benztropine (BZT) analogs and other atypical dopamine uptake inhibitors selectively decrease cocaine self-administration at doses that do not affect responding maintained by other reinforcers. Those effects were further characterized in the current study using a behavioral economic assessment of how response requirement (price) affects reinforcers obtained (consumption) in rats. METHODS Two groups of rats were trained to press levers with food (45-mg pellet) or cocaine (0.32 mg/kg/injection) reinforcement under fixed-ratio (FR) 5-response schedules. In selected sessions, the FR requirement was increased (5-80) during successive 20-min components to determine demand curves, which plot consumption against price. An exponential function was fitted to the data to derive the consumption at zero price (Q 0) and the rate of decrease in consumption (essential value, EV) with increased price. The BZT analogs, AHN1-055, AHN2-005, JHW007 (3.2-10 or 17.8 mg/kg, each), vehicle, or comparison drugs (methylphenidate, ketamine), were administered i.p. before selected demand-curve determinations. RESULTS Consumption of cocaine or food decreased with increased FR requirement. Each drug shifted the demand curve rightward at the lowest doses and leftward/downward at higher doses. The effects on EV and Q 0 were greater for cocaine than for food-reinforced responding. Additionally, the effects of the BZT analogs on EV and Q 0 were greater than those obtained with a standard dopamine transport inhibitor, methylphenidate, and the NMDA antagonist, ketamine (1.0-10.0 mg/kg, each). With these latter drugs, the demand-curve parameters were affected similarly with cocaine and food-maintained responding. CONCLUSIONS The current findings, obtained using a behavioral economic assessment, suggest that BZT analogs selectively decrease the reinforcing effectiveness of cocaine.
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Zou MF, Cao J, Abramyan AM, Kopajtic T, Zanettini C, Guthrie DA, Rais R, Slusher BS, Shi L, Loland CJ, Newman AH. Structure-Activity Relationship Studies on a Series of 3α-[Bis(4-fluorophenyl)methoxy]tropanes and 3α-[Bis(4-fluorophenyl)methylamino]tropanes As Novel Atypical Dopamine Transporter (DAT) Inhibitors for the Treatment of Cocaine Use Disorders. J Med Chem 2017; 60:10172-10187. [PMID: 29227643 PMCID: PMC5746459 DOI: 10.1021/acs.jmedchem.7b01454] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The development of medications to treat cocaine use disorders has thus far defied success, leaving this patient population without pharmacotherapeutic options. As the dopamine transporter (DAT) plays a prominent role in the reinforcing effects of cocaine that can lead to addiction, atypical DAT inhibitors have been developed that prevent cocaine from binding to DAT, but they themselves are not cocaine-like. Herein, a series of novel DAT inhibitors were synthesized, and based on its pharmacological profile, the lead compound 10a was evaluated in phase I metabolic stability studies in mouse liver microsomes and compared to cocaine in locomotor activity and drug discrimination paradigms in mice. A molecular dynamic simulation study supported the hypothesis that atypical DAT inhibitors have similar binding poses at DAT in a conformation that differs from that of cocaine. Such differences may ultimately contribute to their unique behavioral profiles and potential for development as cocaine use disorder therapeutics.
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Affiliation(s)
- Mu-Fa Zou
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Jianjing Cao
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Ara M. Abramyan
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Theresa Kopajtic
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 251 Bayview Blvd., Baltimore, Maryland 21224, United States
| | - Claudio Zanettini
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Daryl A. Guthrie
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Rana Rais
- Department of Neurology, Johns Hopkins Drug Discovery, The Johns Hopkins University School of Medicine, 855 N. Wolfe Street, Baltimore, MD 21205, United States
| | - Barbara S. Slusher
- Department of Neurology, Johns Hopkins Drug Discovery, The Johns Hopkins University School of Medicine, 855 N. Wolfe Street, Baltimore, MD 21205, United States
| | - Lei Shi
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
| | - Claus J. Loland
- Molecular Neuropharmacology and Genetics Laboratory, Department of Neuroscience and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Amy Hauck Newman
- Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, Maryland 21224, United States
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28
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Kohut SJ, Jacobs DS, Rothman RB, Partilla JS, Bergman J, Blough BE. Cocaine-like discriminative stimulus effects of "norepinephrine-preferring" monoamine releasers: time course and interaction studies in rhesus monkeys. Psychopharmacology (Berl) 2017; 234:3455-3465. [PMID: 28889212 PMCID: PMC5747253 DOI: 10.1007/s00213-017-4731-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 08/29/2017] [Indexed: 12/15/2022]
Abstract
RATIONALE The therapeutic potential of monoamine releasers with prominent dopaminergic effects is hindered by their high abuse liability. OBJECTIVES The present study examined the effects of several novel "norepinephrine (NE)-preferring" monoamine releasers relative to non-selective monoamine releasers, d-amphetamine and d-methamphetamine, in rhesus monkeys trained to discriminate cocaine. NE-preferring releasers were approximately 13-fold more potent for NE compared to dopamine release and ranged in potency for serotonin release (PAL-329 < l-methamphetamine < PAL-169). METHODS Adult rhesus macaques were trained to discriminate 0.4 mg/kg, IM cocaine on a 30-response fixed ratio schedule of food reinforcement. Substitution studies determined the extent to which test drugs produced cocaine-like discriminative stimulus effects and their time course. Drug interaction studies determined whether pretreatment with test drugs altered the discriminable effects of cocaine. RESULTS Results show that cocaine, d-amphetamine, and d-methamphetamine dose-dependently substituted for cocaine with similar potencies. Among the "NE-preferring" releasers, PAL-329 and l-methamphetamine also dose-dependently substituted for cocaine but differed in potency. PAL-169 failed to substitute for cocaine up to a dose that disrupted responding. When administered prior to cocaine, only d-amphetamine and PAL-329 significantly shifted the cocaine dose-effect function leftward indicating enhancement of cocaine's discriminative stimulus effects. CONCLUSIONS These data suggest that greater potency for NE relative to dopamine release (up to 13-fold) does not interfere with the ability of a monoamine releaser to produce cocaine-like discriminative effects but that increased serotonin release may have an inhibitory effect. Further characterization of these and other "NE-preferring" monoamine releasers should provide insight into their potential for the management of cocaine addiction.
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Affiliation(s)
- Stephen J Kohut
- McLean Hospital - Harvard Medical School, 115 Mill Street, Belmont, MA, 02478, USA.
| | - David S Jacobs
- McLean Hospital - Harvard Medical School, 115 Mill Street, Belmont, MA, 02478, USA
| | - Richard B Rothman
- National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - John S Partilla
- National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - Jack Bergman
- McLean Hospital - Harvard Medical School, 115 Mill Street, Belmont, MA, 02478, USA
| | - Bruce E Blough
- Research Triangle Institute, Research Triangle Park, NC, USA
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Avelar AJ, Cao J, Newman AH, Beckstead MJ. Atypical dopamine transporter inhibitors R-modafinil and JHW 007 differentially affect D2 autoreceptor neurotransmission and the firing rate of midbrain dopamine neurons. Neuropharmacology 2017; 123:410-419. [PMID: 28625719 PMCID: PMC5546153 DOI: 10.1016/j.neuropharm.2017.06.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 05/17/2017] [Accepted: 06/14/2017] [Indexed: 12/12/2022]
Abstract
Abuse of psychostimulants like cocaine that inhibit dopamine (DA) reuptake through the dopamine transporter (DAT) represents a major public health issue, however FDA-approved pharmacotherapies have yet to be developed. Recently a class of ligands termed "atypical DAT inhibitors" has gained attention due to their range of effectiveness in increasing extracellular DA levels without demonstrating significant abuse liability. These compounds not only hold promise as therapeutic agents to treat stimulant use disorders but also as experimental tools to improve our understanding of DAT function. Here we used patch clamp electrophysiology in mouse brain slices to explore the effects of two atypical DAT inhibitors (R-modafinil and JHW 007) on the physiology of single DA neurons in the substantia nigra and ventral tegmental area. Despite their commonalities of being DAT inhibitors that lack cocaine-like behavioral profiles, these compounds exhibited surprisingly divergent cellular effects. Similar to cocaine, R-modafinil slowed DA neuron firing in a D2 receptor-dependent manner and rapidly enhanced the amplitude and duration of D2 receptor-mediated currents in the midbrain. In contrast, JHW 007 exhibited little effect on firing, slow DAT blockade, and an unexpected inhibition of D2 receptor-mediated currents that may be due to direct D2 receptor antagonism. Furthermore, pretreatment with JHW 007 blunted the cellular effects of cocaine, suggesting that it may be valuable to investigate similar DAT inhibitors as potential therapeutic agents. Further exploration of these and other atypical DAT inhibitors may reveal important cellular effects of compounds that will have potential as pharmacotherapies for treating cocaine use disorders.
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Affiliation(s)
- Alicia J Avelar
- Department of Cellular and Integrative Physiology, UT Health Science Center, San Antonio, TX, 78229, USA.
| | - Jianjing Cao
- Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA.
| | - Amy Hauck Newman
- Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, 21224, USA.
| | - Michael J Beckstead
- Department of Cellular and Integrative Physiology, UT Health Science Center, San Antonio, TX, 78229, USA.
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Cocaine Potency at the Dopamine Transporter Tracks Discrete Motivational States During Cocaine Self-Administration. Neuropsychopharmacology 2017; 42:1893-1904. [PMID: 28139678 PMCID: PMC5520781 DOI: 10.1038/npp.2017.24] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/23/2016] [Accepted: 01/12/2017] [Indexed: 02/07/2023]
Abstract
Although the dopamine transporter (DAT) is the primary site of action for cocaine, and the dopamine system is known to mediate the reinforcing effects of cocaine, the dopaminergic variations underlying individual differences in cocaine self-administration behaviors are not fully understood. Recent advances in the application of economic principles to operant tasks in rodents have allowed for the within-subject, within-session determination of both consummatory and appetitive responding for reinforcers. Here we combined a behavioral economics approach with cocaine self-administration and ex vivo voltammetric recording of dopamine signaling in the core of the nucleus accumbens of rats to determine the relationship between dopamine signaling and discrete aspects of cocaine taking and seeking. We found neither dopamine release or uptake tracked individual differences in cocaine consumption or the reinforcing efficacy of cocaine. Cocaine potency at the DAT was correlated with reinforcing efficacy, but was not related to cocaine consumption. Further, we introduce a novel analysis that determines perseverative responding within the same procedure, and find that cocaine potency at the DAT also tracks differences in perseverative responding. Together, we demonstrate that cocaine effects at the DAT determine the reinforcing efficacy of cocaine, and perseverative responding for sub-threshold doses of cocaine that do not maintain responding when presented in isolation. Surprisingly, we find that variations in cocaine potency do not account for differences in cocaine consumption, suggesting that satiation for cocaine is determined by other targets or mechanisms. Finally, we outline a novel approach for relating drug-target interactions and potency to discrete motivational states during a single self-administration session.
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Hiranita T, Hong WC, Kopajtic T, Katz JL. σ Receptor Effects of N-Substituted Benztropine Analogs: Implications for Antagonism of Cocaine Self-Administration. J Pharmacol Exp Ther 2017; 362:2-13. [PMID: 28442581 PMCID: PMC5454590 DOI: 10.1124/jpet.117.241109] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 04/20/2017] [Indexed: 11/22/2022] Open
Abstract
Several N-substituted benztropine (BZT) analogs are atypical dopamine transport inhibitors as they have affinity for the dopamine transporter (DAT) but have minimal cocaine-like pharmacologic effects and can block numerous effects of cocaine, including its self-administration. Among these compounds, N-methyl (AHN1-055), N-allyl (AHN2-005), and N-butyl (JHW007) analogs of 3α-[bis(4'-fluorophenyl)methoxy]-tropane were more potent in antagonizing self-administration of cocaine and d-methamphetamine than in decreasing food-maintained responding. The antagonism of cocaine self-administration (0.03-1.0 mg/kg per injection) with the above BZT analogs was reproduced in the present study. Further, the stimulant-antagonist effects resembled previously reported effects of pretreatments with combinations of standard DAT inhibitors and σ1-receptor (σ1R) antagonists. Therefore, the present study examined binding of the BZT analogs to σRs, as well as their in vivo σR antagonist effects. Each of the BZT analogs displaced radiolabeled σR ligands with nanomolar affinity. Further, self-administration of the σR agonist DTG (0.1-3.2 mg/kg/injection) was dose dependently blocked by AHN2-005 and JHW007 but potentiated by AHN1-055. In contrast, none of the BZT analogs that were active against DTG self-administration was active against the self-administration of agonists at dopamine D1-like [R(+)-SKF 81297, (±)-SKF 82958 (0.00032-0.01 mg/kg per injection each)], D2-like [R(-)-NPA (0.0001-0.0032 mg/kg per injection), (-)-quinpirole (0.0032-0.1 mg/kg per injection)], or μ-opioid (remifentanil, 0.0001-0.0032 mg/kg per injection) receptors. The present results indicate that behavioral antagonist effects of the N-substituted BZT analogs are specific for abused drugs acting at the DAT and further suggest that σR antagonism contributes to those actions.
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Affiliation(s)
- Takato Hiranita
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health (T.H., T.K., J.L.K.), and Department of Pharmaceutical Sciences, Butler University (W.C.H.), Indianapolis, Indiana
| | - Weimin C Hong
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health (T.H., T.K., J.L.K.), and Department of Pharmaceutical Sciences, Butler University (W.C.H.), Indianapolis, Indiana
| | - Theresa Kopajtic
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health (T.H., T.K., J.L.K.), and Department of Pharmaceutical Sciences, Butler University (W.C.H.), Indianapolis, Indiana
| | - Jonathan L Katz
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health (T.H., T.K., J.L.K.), and Department of Pharmaceutical Sciences, Butler University (W.C.H.), Indianapolis, Indiana
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Relapse to cocaine seeking in an invertebrate. Pharmacol Biochem Behav 2017; 157:41-46. [PMID: 28455125 DOI: 10.1016/j.pbb.2017.04.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 04/07/2017] [Accepted: 04/21/2017] [Indexed: 12/21/2022]
Abstract
Addiction is characterised by cycles of compulsive drug taking, periods of abstinence and episodes of relapse. The extinction/reinstatement paradigm has been extensively used in rodents to model human relapse and explore underlying mechanisms and therapeutics. However, relapse to drug seeking behaviour has not been previously demonstrated in invertebrates. Here, we used a cocaine conditioned place preference (CPP) paradigm in the flatworm, planarian, followed by extinction and reinstatement of drug seeking. Once baseline preference was established for one of two distinctly textured environments (i.e. compartments with a coarse or smooth surface), planarian received pairings of cocaine (5μM) in the non-preferred, and vehicle in the most preferred, environment, and were tested for conditioning thereafter. Cocaine produced robust CPP, measured as a significant increase in the time spent in the cocaine-paired compartment. Subsequently, planarian underwent extinction training, reverting back to their original preference within three sessions. Brief exposure to cocaine (5μM) or methamphetamine (5μM) reinstated cocaine-seeking behaviour. By contrast, the high affinity dopamine transporter inhibitor, (N-(n-butyl)-3α-[bis (4-fluorophenyl) methoxy]-tropane) (JHW007), which in rodents exhibits a neurochemical and behavioural profile distinct from cocaine, was ineffective. The present findings demonstrate for the first time reinstatement of extinguished cocaine seeking in an invertebrate model and suggest that the long-term adaptations underlying drug conditioning and relapse are highly conserved through evolution.
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Hiranita T, Freyberg Z. Importance of Substrate-Coupled Proton Antiport by the Vesicular Monoamine Transporter in the Actions of Amphetamines in Drosophila Brain. ACTA ACUST UNITED AC 2016; 4. [PMID: 28164142 DOI: 10.4172/2329-6488.1000e136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Takato Hiranita
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), AR 72079-9502, USA
| | - Zachary Freyberg
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15213, USA
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Mereu M, Chun LE, Prisinzano TE, Newman AH, Katz JL, Tanda G. The unique psychostimulant profile of (±)-modafinil: investigation of behavioral and neurochemical effects in mice. Eur J Neurosci 2016; 45:167-174. [PMID: 27545285 DOI: 10.1111/ejn.13376] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 07/08/2016] [Accepted: 08/18/2016] [Indexed: 11/29/2022]
Abstract
Blockade of dopamine (DA) reuptake via the dopamine transporter (DAT) is a primary mechanism identified as underlying the therapeutic actions of (±)-modafinil (modafinil) and its R-enantiomer, armodafinil. Herein, we explored the neurochemical and behavioral actions of modafinil to better characterize its psychostimulant profile. Swiss-Webster mice were implanted with microdialysis probes in the nucleus accumbens shell (NAS) or core (NAC) to evaluate changes in DA levels related to acute reinforcing actions of drugs of abuse. Additionally, subjective effects were studied in mice trained to discriminate 10 mg/kg cocaine (i.p.) from saline. Modafinil (17-300 mg/kg, i.p.) significantly increased NAS and NAC DA levels that at the highest doses reached ~300% at 1 h, and lasted > 6 h in duration. These elevated DA levels did not show statistically significant regional differences between the NAS and NAC. Modafinil produced cocaine-like subjective effects at 56-100 mg/kg when administered at 5 and 60 min before the start of the session, and enhanced cocaine effects when the two were administered in combination. Despite sharing subjective effects with cocaine, modafinil's psychostimulant profile was unique compared to that of cocaine and like compounds. Modafinil had lower potency and efficacy than cocaine in stimulating NAS DA. In addition, the cocaine-like subjective effects of modafinil were obtained at lower doses and earlier onset times than expected based on its dopaminergic effects. These studies suggest that although inhibition of DA reuptake may be a primary mechanism underlying modafinil's therapeutic actions, non DA-dependent actions may be playing a role in its psychostimulant profile.
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Affiliation(s)
- Maddalena Mereu
- Medication Development Program, Molecular Targets and Medications Discovery Branch, Department of Health and Human Services, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Lauren E Chun
- Medication Development Program, Molecular Targets and Medications Discovery Branch, Department of Health and Human Services, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Thomas E Prisinzano
- Department of Medicinal Chemistry, The University of Kansas, Lawrence, KS, USA
| | - Amy H Newman
- Medication Development Program, Molecular Targets and Medications Discovery Branch, Department of Health and Human Services, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD, 21224, USA.,Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, Department of Health and Human Services, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Jonathan L Katz
- Psychobiology Section, Molecular Neuropsychiatry Research Branch, Department of Health and Human Services, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | - Gianluigi Tanda
- Medication Development Program, Molecular Targets and Medications Discovery Branch, Department of Health and Human Services, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, 333 Cassell Drive, Baltimore, MD, 21224, USA
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35
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Kohut SJ. Interactions between nicotine and drugs of abuse: a review of preclinical findings. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2016; 43:155-170. [PMID: 27589579 DOI: 10.1080/00952990.2016.1209513] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Polysubstance abuse is common among substance-use disorder patients, and nicotine is one of the most commonly co-used substances. Epidemiological and clinical laboratory studies suggest that nicotine, when combined with other drugs of abuse, increases intake of one or both substances. This review focuses on the preclinical literature regarding nicotine's interaction with alcohol, stimulants (i.e., cocaine, amphetamines), opioids (i.e., morphine, heroin), and Δ9-tetrahydrocannabinol (THC). The current understanding of how these various classes of abused drugs may interact with nicotine on behavioral, physiological, and pharmacological indices that may be important in maintaining co-use of one or both substances in human populations are highlighted. Suggestions as to future areas of research and gaps in knowledge are offered.
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Affiliation(s)
- Stephen J Kohut
- a McLean Hospital and Department of Psychiatry, Harvard Medical School , Belmont , MA , USA
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36
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Hiranita T. (-)-Trans-Δ 9-Tetrahydrocannabinol-Like Discriminative-Stimulus Effects of Gabapentin in Cannabis Users. ACTA ACUST UNITED AC 2016; 4. [PMID: 27376100 DOI: 10.4172/2329-6488.1000e129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Takato Hiranita
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), USA
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Siciliano CA, Ferris MJ, Jones SR. Cocaine self-administration disrupts mesolimbic dopamine circuit function and attenuates dopaminergic responsiveness to cocaine. Eur J Neurosci 2015; 42:2091-6. [PMID: 26037018 PMCID: PMC4540675 DOI: 10.1111/ejn.12970] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 05/29/2015] [Accepted: 05/29/2015] [Indexed: 02/05/2023]
Abstract
Dopaminergic projections from the ventral midbrain to the nucleus accumbens (NAc) have long been implicated in encoding associations between reward availability and environmental stimuli. As such, this circuit is instrumental in guiding behaviors towards obtaining maximal rewards based on previous experience. Cocaine acts on the dopamine system to exert its reinforcing effects and it is thought that cocaine-induced dysregulation of dopamine neurotransmission contributes to the difficulty that cocaine addicts exhibit in selecting environmentally appropriate behaviors. Here we used cocaine self-administration combined with in vivo fast scan cyclic voltammetry in anesthetised rats to examine the function of the ventral tegmental area to NAc projection neurons. Over 5 days of cocaine self-administration (fixed-ratio 1; 1.5 mg/kg/injection; 40 injections/day), animals increased their rate of intake. Following cocaine self-administration, there was a marked reduction in ventral tegmental area-stimulated NAc dopamine release. Additionally, there was a decreased augmentation of stimulated dopamine overflow in response to a cocaine challenge. These findings demonstrate that cocaine induces a hypodopaminergic state, which may contribute to the inflexible drug-taking and drug-seeking behaviors observed in cocaine abusers. Additionally, tolerance to the ability of cocaine to elevate dopamine may lead to increased cocaine intake in order to overcome decreased effects, another hallmark of cocaine abuse.
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Affiliation(s)
- Cody A. Siciliano
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC 27157
| | - Mark J. Ferris
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC 27157
| | - Sara R. Jones
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC 27157
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Hiranita T, Collins GT. Differential Roles for Dopamine D1-Like and D2-Like Receptors in Mediating the Reinforcing Effects of Cocaine: Convergent Evidence from Pharmacological and Genetic Studies. ACTA ACUST UNITED AC 2015; 3. [PMID: 27390753 PMCID: PMC4932862 DOI: 10.4172/2329-6488.1000e124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A series of studies by Drs. Barak Caine, James Woods, Gregory Collins, Jonathan Katz and Takato Hiranita demonstrated a novel and unique reinforcing effect using dopamine (DA) D2-like receptor [D2-like R: D2, D3, and D4 receptor subtypes (respectively, D2R, D3R, and D4R)] agonists in rats and genetically modified mice. In order to understand how important their findings are, a comparison was made regarding the reinforcing effects of DA D2-like R full agonists with those of DA uptake inhibitors and of a DA D1-like receptor [D1-like R, D1 and D5 receptor subtypes (D1R and D5R)] full agonist (±)-SKF 82958.
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Affiliation(s)
- Takato Hiranita
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), 3900 NCTR Road Jefferson, AR 72079-9501, USA
| | - Gregory T Collins
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Dr., Mail Code 7764, San Antonio, TX 78229, USA; South Texas Veterans Health Care System, 7400 Merton Minter Dr, San Antonio, TX 78229, USA
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Söderhielm PC, Andersen J, Munro L, Nielsen AT, Kristensen AS. Substrate and Inhibitor-Specific Conformational Changes in the Human Serotonin Transporter Revealed by Voltage-Clamp Fluorometry. Mol Pharmacol 2015; 88:676-88. [PMID: 26174773 DOI: 10.1124/mol.115.099911] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 07/13/2015] [Indexed: 01/05/2023] Open
Abstract
The serotonin transporter (SERT) regulates neurotransmission by the biogenic monoamine neurotransmitter serotonin (5-HT, 5-hydroxytryptamine) in the central nervous system, and drugs inhibiting SERT are widely used for the treatment of a variety of central nervous system diseases. The conformational dynamics of SERT transport function and inhibition is currently poorly understood. We used voltage-clamp fluorometry to study conformational changes in human SERT (hSERT) during 5-HT transport and inhibitor binding. Cys residues were introduced at 12 positions in hSERT to enable covalent attachment of a rhodamine-based fluorophore. Transport-associated changes in fluorescence from fluorophore-labeled hSERT expressed in Xenopus oocytes could be robustly detected at four positions in hSERT: endogenous Cys109 in the top of transmembrane domain (TM) 1b, Cys substituted for Thr323 in the top of TM6, Ala419 in the interface between TM8 and extracellular loop (EL) 4, and Leu481 in EL5. The reporter positions were used for time-resolved measurement of conformational changes during 5-HT transport and binding of cocaine and the selective serotonin reuptake inhibitors fluoxetine and escitalopram. At all reporter positions, fluorescence changes observed upon substrate application were distinctly different from those observed upon inhibitor application, with respect to relative amplitude or direction. Furthermore, escitalopram, fluoxetine, and cocaine induced a very similar pattern of fluorescent changes overall, which included movements within or around TM1b, EL4, and EL5. Taken together, our data lead us to suggest that competitive inhibitors stabilize hSERT in a state that is different from the apo outward-open conformation as well as inward-facing conformations.
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Affiliation(s)
- Pella C Söderhielm
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Jacob Andersen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Lachlan Munro
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Anne T Nielsen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Anders S Kristensen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
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Reith ME, Blough BE, Hong WC, Jones KT, Schmitt KC, Baumann MH, Partilla JS, Rothman RB, Katz JL. Behavioral, biological, and chemical perspectives on atypical agents targeting the dopamine transporter. Drug Alcohol Depend 2015; 147:1-19. [PMID: 25548026 PMCID: PMC4297708 DOI: 10.1016/j.drugalcdep.2014.12.005] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Revised: 12/04/2014] [Accepted: 12/04/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Treatment of stimulant-use disorders remains a formidable challenge, and the dopamine transporter (DAT) remains a potential target for antagonist or agonist-like substitution therapies. METHODS This review focuses on DAT ligands, such as benztropine, GBR 12909, modafinil, and DAT substrates derived from phenethylamine or cathinone that have atypical DAT-inhibitor effects, either in vitro or in vivo. The compounds are described from a molecular mechanistic, behavioral, and medicinal-chemical perspective. RESULTS Possible mechanisms for atypicality at the molecular level can be deduced from the conformational cycle for substrate translocation. For each conformation, a crystal structure of a bacterial homolog is available, with a possible role of cholesterol, which is also present in the crystal of Drosophila DAT. Although there is a direct relationship between behavioral potencies of most DAT inhibitors and their DAT affinities, a number of compounds bind to the DAT and inhibit dopamine uptake but do not share cocaine-like effects. Such atypical behavior, depending on the compound, may be related to slow DAT association, combined sigma-receptor actions, or bias for cytosol-facing DAT. Some structures are sterically small enough to serve as DAT substrates but large enough to also inhibit transport. Such compounds may display partial DA releasing effects, and may be combined with release or uptake inhibition at other monoamine transporters. CONCLUSIONS Mechanisms of atypical DAT inhibitors may serve as targets for the development of treatments for stimulant abuse. These mechanisms are novel and their further exploration may produce compounds with unique therapeutic potential as treatments for stimulant abuse.
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Affiliation(s)
- Maarten E.A. Reith
- Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA,Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA,Corresponding author: Maarten E.A. Reith, Department of Psychiatry, Alexandria Center of Life Sciences, New York University School of Medicine, 450 E 29th Street, Room 803, New York, NY 10016. Tel.: 212 - 263 8267; Fax: 212 – 263 8183;
| | - Bruce E. Blough
- Center for Drug Discovery, Research Triangle Institute, Research Triangle Park, NC 27709, USA
| | - Weimin C. Hong
- Psychobiology Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| | - Kymry T. Jones
- Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA
| | - Kyle C. Schmitt
- Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA
| | - Michael H. Baumann
- Medicinal Chemistry Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| | - John S. Partilla
- Medicinal Chemistry Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| | - Richard B. Rothman
- Medicinal Chemistry Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
| | - Jonathan L. Katz
- Psychobiology Section, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA
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Hiranita T. Cocaine Antagonists; Studies on Cocaine Self-Administration. JOURNAL OF ALCOHOLISM AND DRUG DEPENDENCE 2015; 3. [PMID: 27398394 DOI: 10.4172/2329-6488.1000e125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Takato Hiranita
- Division of Neurotoxicology, National Center for Toxicological Research (NCTR), U.S. Food and Drug Administration (FDA), USA
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