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Newman AH, Xi ZX, Heidbreder C. Current Perspectives on Selective Dopamine D 3 Receptor Antagonists/Partial Agonists as Pharmacotherapeutics for Opioid and Psychostimulant Use Disorders. Curr Top Behav Neurosci 2023; 60:157-201. [PMID: 35543868 PMCID: PMC9652482 DOI: 10.1007/7854_2022_347] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Over three decades of evidence indicate that dopamine (DA) D3 receptors (D3R) are involved in the control of drug-seeking behavior and may play an important role in the pathophysiology of substance use disorders (SUD). The expectation that a selective D3R antagonist/partial agonist would be efficacious for the treatment of SUD is based on the following key observations. First, D3R are distributed in strategic areas belonging to the mesolimbic DA system such as the ventral striatum, midbrain, and ventral pallidum, which have been associated with behaviors controlled by the presentation of drug-associated cues. Second, repeated exposure to drugs of abuse produces neuroadaptations in the D3R system. Third, the synthesis and characterization of highly potent and selective D3R antagonists/partial agonists have further strengthened the role of the D3R in SUD. Based on extensive preclinical and preliminary clinical evidence, the D3R shows promise as a target for the development of pharmacotherapies for SUD as reflected by their potential to (1) regulate the motivation to self-administer drugs and (2) disrupt the responsiveness to drug-associated stimuli that play a key role in reinstatement of drug-seeking behavior triggered by re-exposure to the drug itself, drug-associated environmental cues, or stress. The availability of PET ligands to assess clinically relevant receptor occupancy by selective D3R antagonists/partial agonists, the definition of reliable dosing, and the prospect of using human laboratory models may further guide the design of clinical proof of concept studies. Pivotal clinical trials for more rapid progression of this target toward regulatory approval are urgently required. Finally, the discovery that highly selective D3R antagonists, such as R-VK4-116 and R-VK4-40, do not adversely affect peripheral biometrics or cardiovascular effects alone or in the presence of oxycodone or cocaine suggests that this class of drugs has great potential in safely treating psychostimulant and/or opioid use disorders.
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Affiliation(s)
- Amy Hauck Newman
- Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse-Intramural Research Program, Baltimore, MD, USA.
| | - Zheng-Xiong Xi
- Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse-Intramural Research Program, Baltimore, MD, USA
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Interaction of the preferential D3 agonist (+)PHNO with dopamine D3-D2 receptor heterodimers and diverse classes of monoamine receptors: Relevance for PET imaging. Eur J Pharmacol 2022; 925:175016. [DOI: 10.1016/j.ejphar.2022.175016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 04/21/2022] [Accepted: 05/04/2022] [Indexed: 11/21/2022]
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Madireddy S, Madireddy S. Therapeutic Interventions to Mitigate Mitochondrial Dysfunction and Oxidative Stress–Induced Damage in Patients with Bipolar Disorder. Int J Mol Sci 2022; 23:ijms23031844. [PMID: 35163764 PMCID: PMC8836876 DOI: 10.3390/ijms23031844] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 12/26/2021] [Accepted: 12/30/2021] [Indexed: 01/10/2023] Open
Abstract
Bipolar disorder (BD) is characterized by mood changes, including recurrent manic, hypomanic, and depressive episodes, which may involve mixed symptoms. Despite the progress in neurobiological research, the pathophysiology of BD has not been extensively described to date. Progress in the understanding of the neurobiology driving BD could help facilitate the discovery of therapeutic targets and biomarkers for its early detection. Oxidative stress (OS), which damages biomolecules and causes mitochondrial and dopamine system dysfunctions, is a persistent finding in patients with BD. Inflammation and immune dysfunction might also play a role in BD pathophysiology. Specific nutrient supplements (nutraceuticals) may target neurobiological pathways suggested to be perturbed in BD, such as inflammation, mitochondrial dysfunction, and OS. Consequently, nutraceuticals may be used in the adjunctive treatment of BD. This paper summarizes the possible roles of OS, mitochondrial dysfunction, and immune system dysregulation in the onset of BD. It then discusses OS-mitigating strategies that may serve as therapeutic interventions for BD. It also analyzes the relationship between diet and BD as well as the use of nutritional interventions in the treatment of BD. In addition, it addresses the use of lithium therapy; novel antipsychotic agents, including clozapine, olanzapine, risperidone, cariprazine, and quetiapine; and anti-inflammatory agents to treat BD. Furthermore, it reviews the efficacy of the most used therapies for BD, such as cognitive–behavioral therapy, bright light therapy, imagery-focused cognitive therapy, and electroconvulsive therapy. A better understanding of the roles of OS, mitochondrial dysfunction, and inflammation in the pathogenesis of bipolar disorder, along with a stronger elucidation of the therapeutic functions of antioxidants, antipsychotics, anti-inflammatory agents, lithium therapy, and light therapies, may lead to improved strategies for the treatment and prevention of bipolar disorder.
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Affiliation(s)
- Sahithi Madireddy
- Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Correspondence:
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Kiss B, Krámos B, Laszlovszky I. Potential Mechanisms for Why Not All Antipsychotics Are Able to Occupy Dopamine D 3 Receptors in the Brain in vivo. Front Psychiatry 2022; 13:785592. [PMID: 35401257 PMCID: PMC8987915 DOI: 10.3389/fpsyt.2022.785592] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 02/25/2022] [Indexed: 11/29/2022] Open
Abstract
Dysfunctions of the dopaminergic system are believed to play a major role in the core symptoms of schizophrenia such as positive, negative, and cognitive symptoms. The first line of treatment of schizophrenia are antipsychotics, a class of medications that targets several neurotransmitter receptors in the brain, including dopaminergic, serotonergic, adrenergic and/or muscarinic receptors, depending on the given agent. Although the currently used antipsychotics display in vitro activity at several receptors, majority of them share the common property of having high/moderate in vitro affinity for dopamine D2 receptors (D2Rs) and D3 receptors (D3Rs). In terms of mode of action, these antipsychotics are either antagonist or partial agonist at the above-mentioned receptors. Although D2Rs and D3Rs possess high degree of homology in their molecular structure, have common signaling pathways and similar in vitro pharmacology, they have different in vivo pharmacology and therefore behavioral roles. The aim of this review, with summarizing preclinical and clinical evidence is to demonstrate that while currently used antipsychotics display substantial in vitro affinity for both D3Rs and D2Rs, only very few can significantly occupy D3Rs in vivo. The relative importance of the level of endogenous extracellular dopamine in the brain and the degree of in vitro D3Rs receptor affinity and selectivity as determinant factors for in vivo D3Rs occupancy by antipsychotics, are also discussed.
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Affiliation(s)
- Béla Kiss
- Pharmacological and Drug Safety Research, Gedeon Richter Plc., Budapest, Hungary
| | - Balázs Krámos
- Spectroscopic Research Department, Gedeon Richter Plc., Budapest, Hungary
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Flace P, Livrea P, Basile GA, Galletta D, Bizzoca A, Gennarini G, Bertino S, Branca JJV, Gulisano M, Bianconi S, Bramanti A, Anastasi G. The Cerebellar Dopaminergic System. Front Syst Neurosci 2021; 15:650614. [PMID: 34421548 PMCID: PMC8375553 DOI: 10.3389/fnsys.2021.650614] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 05/04/2021] [Indexed: 12/04/2022] Open
Abstract
In the central nervous system (CNS), dopamine (DA) is involved in motor and cognitive functions. Although the cerebellum is not been considered an elective dopaminergic region, studies attributed to it a critical role in dopamine deficit-related neurological and psychiatric disorders [e.g., Parkinson's disease (PD) and schizophrenia (SCZ)]. Data on the cerebellar dopaminergic neuronal system are still lacking. Nevertheless, biochemical studies detected in the mammalians cerebellum high dopamine levels, while chemical neuroanatomy studies revealed the presence of midbrain dopaminergic afferents to the cerebellum as well as wide distribution of the dopaminergic receptor subtypes (DRD1-DRD5). The present review summarizes the data on the cerebellar dopaminergic system including its involvement in associative and projective circuits. Furthermore, this study also briefly discusses the role of the cerebellar dopaminergic system in some neurologic and psychiatric disorders and suggests its potential involvement as a target in pharmacologic and non-pharmacologic treatments.
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Affiliation(s)
- Paolo Flace
- Medical School, University of Bari ‘Aldo Moro', Bari, Italy
| | | | - Gianpaolo Antonio Basile
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | - Diana Galletta
- Unit of Psychiatry and Psychology, Federico II University Hospital, Naples, Italy
| | - Antonella Bizzoca
- Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari “Aldo Moro”, Bari, Italy
| | - Gianfranco Gennarini
- Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari “Aldo Moro”, Bari, Italy
| | - Salvatore Bertino
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
| | | | - Massimo Gulisano
- Department of Experimental and Clinical Medicine, University of Firenze, Firenze, Italy
| | - Simona Bianconi
- Physical, Rehabilitation Medicine and Sport Medicine Unit, University Hospital “G. Martino”, Messina, Italy
| | - Alessia Bramanti
- Scientific Institute for Research, Hospitalization and Health Care IRCCS “Centro Neurolesi Bonino Pulejo”, Messina, Italy
| | - Giuseppe Anastasi
- Department of Biomedical, Dental Sciences and Morphological and Functional Images, University of Messina, Messina, Italy
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Earley WR, Burgess MV, Khan B, Rekeda L, Suppes T, Tohen M, Calabrese JR. Efficacy and safety of cariprazine in bipolar I depression: A double-blind, placebo-controlled phase 3 study. Bipolar Disord 2020; 22:372-384. [PMID: 31628698 PMCID: PMC7318333 DOI: 10.1111/bdi.12852] [Citation(s) in RCA: 181] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE To assess the efficacy, safety, and tolerability of cariprazine in the treatment of the depressed phase of bipolar I disorder in adults (NCT02670538). METHODS In this phase 3 double-blind placebo-controlled study, adult patients with bipolar I disorder according to the Diagnostic and Statistical Manual - 5th Edition criteria and a current depressive episode were randomized to placebo (n = 167), cariprazine 1.5 mg/day (n = 168) or cariprazine 3.0 mg/day (n = 158). Efficacy parameters were changes in the Montgomery-Åsberg Depression Rating Scale (MADRS) total scores (primary) and Clinical Global Impressions - Severity (CGI-S) scores (secondary) from baseline to Week 6 compared to placebo. A mixed-model for repeated measures was used to estimate the least-squares mean differences (LSMD); P-values were adjusted for multiplicity. Adverse events (AEs), laboratory results, vital signs, and suicide risk were monitored. RESULTS Cariprazine 1.5 mg/day significantly reduced depressive symptoms on the primary (MADRS LSMD = -2.5; adjusted P = .0417) and secondary (CGI-S LSMD = -0.3; adjusted P = .0417) efficacy parameters vs placebo; differences were not statistically significant for cariprazine 3.0 mg/day. Common treatment-emergent AEs (≥5% in either cariprazine group and at least twice the incidence of placebo) were akathisia, restlessness, nausea, and fatigue. Mean metabolic parameter changes were low and generally comparable among groups; mean weight increases were ≤0.5 kg for all groups. CONCLUSIONS Cariprazine 1.5 mg/day significantly reduced depressive symptoms in adults with bipolar I depression compared to placebo, but differences were not significant for cariprazine 3.0 mg/day. The safety and tolerability profiles were similar to previous studies of cariprazine.
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Affiliation(s)
| | | | - Barbara Khan
- Department of Clinical DevelopmentAllergan plcMadisonNJUSA
| | | | - Trisha Suppes
- Department of Psychiatry and Behavioral SciencesStanford University School of Medicine and V.A. Palo Alto Health Care SystemPalo AltoCAUSA
| | - Mauricio Tohen
- Department of Psychiatry and Behavioral SciencesUniversity of New MexicoAlbuquerqueNMUSA
| | - Joseph R. Calabrese
- Department of PsychiatryCase Western Reserve School of MedicineClevelandOHUSA
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Kiss B, Némethy Z, Fazekas K, Kurkó D, Gyertyán I, Sághy K, Laszlovszky I, Farkas B, Kirschner N, Bolf-Terjéki E, Balázs O, Lendvai B. Preclinical pharmacodynamic and pharmacokinetic characterization of the major metabolites of cariprazine. Drug Des Devel Ther 2019; 13:3229-3248. [PMID: 31571826 PMCID: PMC6754336 DOI: 10.2147/dddt.s188760] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 05/01/2019] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION Cariprazine, a dopamine D3-preferring D3/D2 receptor partial agonist and serotonin 5-HT1A receptor partial agonist, has two major human metabolites, desmethyl-cariprazine (DCAR) and didesmethyl-cariprazine (DDCAR). The metabolite pharmacology was profiled to understand the contribution to cariprazine efficacy. METHODS In vitro receptor binding and functional assays, electrophysiology, animal models, microdialysis, and kinetic-metabolism approaches were used to characterize the pharmacology of DCAR and DDCAR. RESULTS Similar to cariprazine, both metabolites showed high affinity for human D3, D2L, 5-HT1A, 5-HT2A, and 5-HT2B receptors, albeit with higher selectivity than cariprazine for D3 versus D2 receptors. In [35S]GTPγS binding assays, cariprazine and DDCAR were antagonists in membranes from rat striatum and from cells expressing human D2 and D3 receptors, and were partial agonists in membranes from rat hippocampus. In cAMP signaling assays, cariprazine, DCAR, and DDCAR acted as partial agonists at D2 and D3 receptors; cariprazine and DDCAR were full agonists, whereas DCAR was a partial agonist at 5-HT1A receptors. Cariprazine, DCAR, and DDCAR were pure antagonists at human 5-HT2B receptors. Cariprazine and DDCAR increased rat striatal dopamine and reduced cortical serotonin turnover. Cariprazine and DDCAR showed similar in vivo D3 receptor occupancy in rat brain; however, cariprazine was more potent for D2 receptor occupancy. Both cariprazine and DDCAR dose-dependently but partially suppressed the spontaneous activity of midbrain dopaminergic neurons in rats, with the parent compound being more potent but shorter acting than its metabolite. Consistent with the D2 receptor occupancy profile, DDCAR was 3- to 10-fold less potent than cariprazine in rodent models of antipsychotic-like activity. Following acute cariprazine administration, DDCAR was detected in the rodent brain but at much lower levels than cariprazine. CONCLUSION Overall, in vitro and in vivo pharmacological profiles of DCAR and DDCAR demonstrated high similarity with cariprazine, suggesting that the major metabolites of cariprazine contribute significantly to its clinical efficacy.
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Affiliation(s)
- Béla Kiss
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Zsolt Némethy
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Károly Fazekas
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Dalma Kurkó
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - István Gyertyán
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Katalin Sághy
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - István Laszlovszky
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Bence Farkas
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Norbert Kirschner
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Etelka Bolf-Terjéki
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Ottilia Balázs
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
| | - Balázs Lendvai
- Pharmacological and Drug Safety Research, Gedeon Richter Plc, Budapest, Hungary
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Di Ciano P, Mansouri E, Tong J, Wilson AA, Houle S, Boileau I, Duvauchelle T, Robert P, Schwartz JC, Le Foll B. Occupancy of dopamine D 2 and D 3 receptors by a novel D3 partial agonist BP1.4979: a [ 11C]-(+)-PHNO PET study in humans. Neuropsychopharmacology 2019; 44:1284-1290. [PMID: 30659274 PMCID: PMC6785153 DOI: 10.1038/s41386-018-0285-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 10/15/2018] [Accepted: 11/13/2018] [Indexed: 11/09/2022]
Abstract
There has been considerable interest in the development of dopamine D3 receptor (DRD3) partial agonists and antagonists for the treatment of substance use disorders. Pre-clinical evidence overwhelmingly supports the use of these drugs, but translation to humans has remained elusive due to the lack of selective compounds that are suitable for use in humans. Although it has been established for full antagonists, little in vivo occupancy data are available with DRD3 partial agonists. Here we investigate for the first time in healthy controls, the in vivo occupancy of a novel D3 partial agonist (BP1.4979) at the DRD3 and DRD2. Participants received either a single dose (1, 3, 10 or 30 mg) or a subchronic regimen (5-7 days, q.d. or b.i.d) of BP1.4979, with the last dose given at 1, 12 or 24 h prior to scanning with [11C]-(+)-PHNO. Single and subchronic administration of BP1.4979 dose-dependently occupied the DRD3 and DRD2, and this occupancy was preferential for the DRD3, notably at longer time points after administration of BP1.4979. Also consistent with preference for the DRD3, prolactin levels were minimally increased, and no subjective effects of BP1.4979 were reported. Serum levels of BP1.4979 were higher than its active metabolite, BP1.6239, while no notable increases in the inactive metabolite, BP1.6197, were found. These findings indicate the range of doses that can be used to occupy selectively the DRD3 over the DRD2 with BP1.4979 and speak to the use of in vivo imaging approaches in dose finding studies.
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Affiliation(s)
- Patricia Di Ciano
- 0000 0000 8793 5925grid.155956.bTranslational Addiction Research Laboratory, Centre for Addiction and Mental Health, 33 Russell Street, Toronto, ON M5S 2S1 Canada
| | - Esmaeil Mansouri
- 0000 0000 8793 5925grid.155956.bAddiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada ,0000 0001 2157 2938grid.17063.33Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Junchao Tong
- 0000 0000 8793 5925grid.155956.bPreclinical imaging, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada ,0000 0000 8793 5925grid.155956.bHuman Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada
| | - Alan A. Wilson
- 0000 0001 2157 2938grid.17063.33Institute of Medical Sciences, University of Toronto, Toronto, Canada ,0000 0000 8793 5925grid.155956.bCampbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada ,0000 0000 8793 5925grid.155956.bResearch Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON M5T 1R Canada ,0000 0001 2157 2938grid.17063.33Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Sylvain Houle
- 0000 0001 2157 2938grid.17063.33Institute of Medical Sciences, University of Toronto, Toronto, Canada ,0000 0000 8793 5925grid.155956.bCampbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada ,0000 0000 8793 5925grid.155956.bResearch Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON M5T 1R Canada ,0000 0001 2157 2938grid.17063.33Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Isabelle Boileau
- 0000 0000 8793 5925grid.155956.bAddiction Imaging Research Group, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada ,0000 0001 2157 2938grid.17063.33Institute of Medical Sciences, University of Toronto, Toronto, Canada ,0000 0000 8793 5925grid.155956.bCampbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada ,0000 0000 8793 5925grid.155956.bResearch Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON M5T 1R Canada ,0000 0001 2157 2938grid.17063.33Department of Psychiatry, University of Toronto, Toronto, Canada ,0000 0000 8793 5925grid.155956.bAddiction Program, Centre for Addiction and Mental Health, Toronto, ON M5S 2S1 Canada
| | | | | | | | - Bernard Le Foll
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, 33 Russell Street, Toronto, ON, M5S 2S1, Canada. .,Institute of Medical Sciences, University of Toronto, Toronto, Canada. .,Department of Psychiatry, University of Toronto, Toronto, Canada. .,Addiction Program, Centre for Addiction and Mental Health, Toronto, ON, M5S 2S1, Canada. .,Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada.
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Earley W, Burgess MV, Rekeda L, Dickinson R, Szatmári B, Németh G, McIntyre RS, Sachs GS, Yatham LN. Cariprazine Treatment of Bipolar Depression: A Randomized Double-Blind Placebo-Controlled Phase 3 Study. Am J Psychiatry 2019; 176:439-448. [PMID: 30845817 DOI: 10.1176/appi.ajp.2018.18070824] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Cariprazine, a dopamine D3/D2 and 5-HT1A receptor partial agonist, was found to be effective in treating bipolar I depression in a previous phase 2 study. This phase 3 study further assessed the efficacy, safety, and tolerability of cariprazine in bipolar I depression. METHODS In a double-blind placebo-controlled study, adult participants (18-65 years old) who met DSM-5 criteria for bipolar I disorder and a current depressive episode were randomly assigned to receive placebo (N=158) or cariprazine at 1.5 mg/day (N=157) or 3.0 mg/day (N=165). The primary and secondary efficacy parameters were changes from baseline to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) score and Clinical Global Impressions severity (CGI-S) score, respectively. Least squares mean differences were estimated using a mixed model for repeated measures, and p values were adjusted for multiplicity. RESULTS Both dosages of cariprazine were significantly more effective than placebo in improving depressive symptoms (reducing MADRS total score); the least squares mean differences were -2.5 (95% CI=-4.6, -0.4) for cariprazine at 1.5 mg/day and -3.0 (95% CI=-5.1, -0.9) for cariprazine at 3.0 mg/day. Both cariprazine dosages were associated with lower CGI-S scores compared with placebo, but the differences did not reach statistical significance after adjustment for multiplicity (least squares mean difference, -0.2 [95% CI=-0.5, 0.0] for the 1.5 mg/day group and -0.3 [95% CI=-0.5, 0.0] for the 3.0 mg/day group). Common treatment-emergent adverse events (in at least 5% of participants in either cariprazine treatment group and twice the rate of the placebo group) were nausea, akathisia, dizziness, and sedation. Mean changes in weight and metabolic parameters were relatively small and comparable across groups. CONCLUSIONS Cariprazine, at both 1.5 mg/day and 3.0 mg/day, was effective, generally well tolerated, and relatively safe in reducing depressive symptoms in adults with bipolar I depression.
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Affiliation(s)
- Willie Earley
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - Maria Victoria Burgess
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - Ludmyla Rekeda
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - Regan Dickinson
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - Balázs Szatmári
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - György Németh
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - Roger S McIntyre
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - Gary S Sachs
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
| | - Lakshmi N Yatham
- Allergan, Madison, N.J. (Earley, Burgess, Rekeda, Dickinson); Gedeon Richter, Budapest, Hungary (Szatmári, Németh); the Mood Disorders Psychopharmacology Unit, University Health Network, Toronto (McIntyre); the Department of Psychiatry, Harvard Medical School, and the Bipolar Clinic and Research Program, Massachusetts General Hospital, Boston (Sachs); and the Department of Psychiatry, University of British Columbia, Vancouver (Yatham)
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10
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Caravaggio F, Iwata Y, Kim J, Shah P, Gerretsen P, Remington G, Graff-Guerrero A. What proportion of striatal D2 receptors are occupied by endogenous dopamine at baseline? A meta-analysis with implications for understanding antipsychotic occupancy. Neuropharmacology 2019; 163:107591. [PMID: 30940535 DOI: 10.1016/j.neuropharm.2019.03.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/25/2019] [Accepted: 03/27/2019] [Indexed: 11/30/2022]
Abstract
Using molecular imaging techniques - positron emission tomography (PET) and single-photon emission computed tomography (SPECT) - in conjunction with an acute dopamine depletion challenge (alpha-methyl-para-tyrosine) it is possible to estimate endogenous dopamine levels occupying striatal dopamine D2 receptors (D2R) in humans in vivo. However, it is unclear what proportion of striatal D2R are occupied by endogenous dopamine under normal conditions. This is important since it has been suggested that in schizophrenia there may be a substantial proportion of striatal D2R which are occupied by endogenous dopamine and not accessible by therapeutic doses of antipsychotics. In order to clarify these issues, we conducted a meta-analysis of dopamine depletion studies using substituted benzamide radiotracers in healthy persons. This meta-analysis suggests that anywhere from 8 to 21% (weighted average 11%) of striatal D2R may be occupied by endogenous dopamine at baseline. Using these estimates, we propose an updated occupancy model and tentatively suggest that antipsychotics inhibit a smaller proportion of the total pool of striatal D2R in vivo than previously acknowledged. This article is part of the issue entitled 'Special Issue on Antipsychotics'.
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Affiliation(s)
- Fernando Caravaggio
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, Toronto, Ontario, M5T 1R8, Canada.
| | - Yusuke Iwata
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, Toronto, Ontario, M5T 1R8, Canada
| | - Julia Kim
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Institute of Medical Science, University of Toronto, 1 Kings College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Parita Shah
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Institute of Medical Science, University of Toronto, 1 Kings College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Philip Gerretsen
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Institute of Medical Science, University of Toronto, 1 Kings College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Gary Remington
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Institute of Medical Science, University of Toronto, 1 Kings College Circle, Toronto, Ontario, M5S 1A8, Canada
| | - Ariel Graff-Guerrero
- Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Institute of Medical Science, University of Toronto, 1 Kings College Circle, Toronto, Ontario, M5S 1A8, Canada
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11
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Qian M, Wouters E, Dalton JAR, Risseeuw MDP, Crans RAJ, Stove C, Giraldo J, Van Craenenbroeck K, Van Calenbergh S. Synthesis toward Bivalent Ligands for the Dopamine D 2 and Metabotropic Glutamate 5 Receptors. J Med Chem 2018; 61:8212-8225. [PMID: 30180563 DOI: 10.1021/acs.jmedchem.8b00671] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In this study, we designed and synthesized heterobivalent ligands targeting heteromers consisting of the metabotropic glutamate 5 receptor (mGluR5) and the dopamine D2 receptor (D2R). Bivalent ligand 22a with a linker consisting of 20 atoms showed 4-fold increase in affinity for cells coexpressing D2R and mGluR5 compared to cells solely expressing D2R. Likewise, the affinity of 22a for mGluR5 increased 2-fold in the coexpressing cells. Additionally, 22a exhibited a 5-fold higher mGluR5 affinity than its monovalent precursor 21a in cells coexpressing D2R and mGluR5. These results indicate that 22a is able to bridge binding sites on both receptors constituting the heterodimer. Likewise, cAMP assays revealed that 22a had a 4-fold higher potency in stable D2R and mGluR5 coexpressing cell lines than 1. Furthermore, molecular modeling reveals that 22a is able to simultaneously bind both receptors by passing between the TM5-TM6 interface and establishing six protein-ligand H-bonds.
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Affiliation(s)
- Mingcheng Qian
- Laboratory for Medicinal Chemistry (FFW) , Ghent University , Ottergemsesteenweg 460 , B-9000 Ghent , Belgium.,Laboratory of Toxicology , Ghent University , Ottergemsesteenweg 460 , B-9000 Ghent , Belgium
| | - Elise Wouters
- Laboratory of Toxicology , Ghent University , Ottergemsesteenweg 460 , B-9000 Ghent , Belgium
| | - James A R Dalton
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Unitat de Bioestadística, Institut de Neurociències , Universitat Autònoma de Barcelona , 08193 Bellaterra , Spain.,Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM , Universitat Autònoma de Barcelona , 08193 Bellaterra , Spain.,Unitat de Neurociència Traslacional, Parc Taulí Hospital Universitari, Institut d'Investigació i Innovació Parc Taulí (I3PT), Institut de Neurociències , Universitat Autònoma de Barcelona , 08193 Bellaterra , Spain
| | - Martijn D P Risseeuw
- Laboratory for Medicinal Chemistry (FFW) , Ghent University , Ottergemsesteenweg 460 , B-9000 Ghent , Belgium
| | - René A J Crans
- Laboratory of Toxicology , Ghent University , Ottergemsesteenweg 460 , B-9000 Ghent , Belgium
| | - Christophe Stove
- Laboratory of Toxicology , Ghent University , Ottergemsesteenweg 460 , B-9000 Ghent , Belgium
| | - Jesús Giraldo
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Unitat de Bioestadística, Institut de Neurociències , Universitat Autònoma de Barcelona , 08193 Bellaterra , Spain.,Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM , Universitat Autònoma de Barcelona , 08193 Bellaterra , Spain.,Unitat de Neurociència Traslacional, Parc Taulí Hospital Universitari, Institut d'Investigació i Innovació Parc Taulí (I3PT), Institut de Neurociències , Universitat Autònoma de Barcelona , 08193 Bellaterra , Spain
| | | | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry (FFW) , Ghent University , Ottergemsesteenweg 460 , B-9000 Ghent , Belgium
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12
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Qian M, Vasudevan L, Huysentruyt J, Risseeuw MDP, Stove C, Vanderheyden PML, Van Craenenbroeck K, Van Calenbergh S. Design, Synthesis, and Biological Evaluation of Bivalent Ligands Targeting Dopamine D 2 -Like Receptors and the μ-Opioid Receptor. ChemMedChem 2018; 13:944-956. [PMID: 29451744 DOI: 10.1002/cmdc.201700787] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Indexed: 12/13/2022]
Abstract
Currently, there is mounting evidence that intermolecular receptor-receptor interactions may result in altered receptor recognition, pharmacology and signaling. Heterobivalent ligands have been proven useful as molecular probes for confirming and targeting heteromeric receptors. This report describes the design and synthesis of novel heterobivalent ligands for dopamine D2 -like receptors (D2 -likeR) and the μ-opioid receptor (μOR) and their evaluation using ligand binding and functional assays. Interestingly, we identified a potent bivalent ligand that contains a short 18-atom linker and combines good potency with high efficacy both in β-arrestin 2 recruitment for μOR and MAPK-P for D4 R. Furthermore, this compound was characterized by a biphasic competition binding curve for the D4 R-μOR heterodimer, indicative of a bivalent binding mode. As this compound possibly bridges the D4 R-μOR heterodimer, it could be used as a pharmacological tool to further investigate the interactions of D4 R and μOR.
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Affiliation(s)
- Mingcheng Qian
- Laboratory for Medicinal Chemistry, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium.,Laboratory of Toxicology, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Lakshmi Vasudevan
- Laboratory of Toxicology, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Jelle Huysentruyt
- Laboratory of Toxicology, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Martijn D P Risseeuw
- Laboratory for Medicinal Chemistry, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Christophe Stove
- Laboratory of Toxicology, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
| | - Patrick M L Vanderheyden
- Department Research Group of Molecular and Biochemical Pharmacology, Faculty of Sciences and Bioengineering Sciences, Vrije Universiteit Brussel, VUB-MBFA, Pleinlaan 2, 1050, Brussels, Belgium
| | | | - Serge Van Calenbergh
- Laboratory for Medicinal Chemistry, Ghent University, Ottergemsesteenweg 460, 9000, Ghent, Belgium
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13
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Di Ciano P, Tyndale RF, Mansouri E, Hendershot CS, Wilson AA, Lagzdins D, Houle S, Boileau I, Le Foll B. Influence of Nicotine Metabolism Ratio on [11C]-(+)-PHNO PET Binding in Tobacco Smokers. Int J Neuropsychopharmacol 2018; 21:503-512. [PMID: 29346545 PMCID: PMC6007643 DOI: 10.1093/ijnp/pyx119] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Identifying the biological basis of smoking cessation success is of growing interest. The rate of nicotine metabolism, measured by the nicotine metabolite ratio, affects multiple aspects of nicotine dependence. Fast nicotine metabolizers tend to smoke more, experience more withdrawal and craving, and have lower cessation rates compared with slow metabolizers. The nicotine metabolite ratio predicts treatment response, and differences in brain activation between fast metabolizers and slow metabolizers have been reported in fMRI studies. As reinforcing/rewarding effects of tobacco are associated with dopamine transmission, the purpose of the present study was to study the dopaminergic system in human smokers based on their nicotine metabolite ratio. METHODS The first aim of the study was to explore if there were differences in D2 and D3 receptor binding between fast metabolizers and slow metabolizers during abstinence. The second aim was to explore smoking-induced dopamine release in both groups. Participants underwent 2 [11C]-(+)-PHNO PET scans: one scan during abstinence and the other after smoking a tobacco cigarette. Subjective measures were recorded and blood was drawn for measurement of nicotine and cotinine levels. RESULTS During abstinence, slow metabolizers (n = 13) had lower [11C]-(+)-PHNO binding potential than fast metabolizers (n = 15) restricted to the D2 regions of the associative striatum and sensorimotor striatum. After smoking a cigarette, [11C]-(+)-PHNO binding potential was decreased in the limbic striatum and ventral pallidum, suggestive of increases in dopamine, but there were no nicotine metabolite ratio differences. CONCLUSIONS Further studies are required to delineate if differences in [11C]-(+)-PHNO binding between slow metabolizers and fast metabolizers at abstinence baseline are preexisting traits or induced by prolonged tobacco use.
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Affiliation(s)
- Patricia Di Ciano
- Addictions Division, Centre for Addiction and Mental Health, Toronto, Canada
| | - Rachel F Tyndale
- Campbell Family Mental Health Research Institute Toronto, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada,Department of Pharmacology and Toxicology,Department of Psychiatry, University of Toronto, Toronto, Canada
| | | | - Christian S Hendershot
- Campbell Family Mental Health Research Institute Toronto, Canada,Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Alan A Wilson
- Campbell Family Mental Health Research Institute Toronto, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada,Department of Psychiatry, University of Toronto, Toronto, Canada,Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Dina Lagzdins
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, Canada
| | - Sylvain Houle
- Campbell Family Mental Health Research Institute Toronto, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada,Department of Psychiatry, University of Toronto, Toronto, Canada,Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Isabelle Boileau
- Addictions Division, Centre for Addiction and Mental Health, Toronto, Canada,Addiction Imaging Research Group Toronto, Canada,Campbell Family Mental Health Research Institute Toronto, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada,Department of Psychiatry, University of Toronto, Toronto, Canada,Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, Toronto, Canada,Addictions Division, Centre for Addiction and Mental Health, Toronto, Canada,Campbell Family Mental Health Research Institute Toronto, Canada,Department of Pharmacology and Toxicology,Department of Psychiatry, University of Toronto, Toronto, Canada,Institute of Medical Sciences, University of Toronto, Toronto, Canada,Correspondence: Bernard Le Foll, MD, PhD, Centre for Addiction and Mental Health., 33 Russell Street, Toronto, Ontario, M5S 2S1 ()
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14
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Di Ciano P, Cormick PM, Stefan C, Wong E, Kim A, Remington G, Le Foll B. The effects of buspirone on occupancy of dopamine receptors and the rat gambling task. Psychopharmacology (Berl) 2017; 234:3309-3320. [PMID: 28825117 DOI: 10.1007/s00213-017-4715-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/04/2017] [Indexed: 11/27/2022]
Abstract
BACKGROUND The dopamine D3 receptor (DRD3) has been proposed as a target for drug development for the treatment of addictive disorders. Recently, the anxiolytic buspirone has been shown to have affinity for DRD3 and DRD4, and interest in repurposing it for addictive disorders has grown. METHODS Binding of [3H]-(+)-PHNO in the rat cerebellum and striatum was used to measure occupancy by buspirone of DRD3 or DRD2, respectively. Effects of buspirone in the rat gambling task (rGT) and the five-choice serial reaction time task (5-CSRTT) were examined. RESULTS Buspirone occupied both the DRD2 and DRD3 at high doses and the DRD3, but not the DRD2, in the narrow dose range of 3 mg/kg. At 10 mg/kg, a disruption of performance on rGT was observed. All measures of performance on the rGT, except for perseverations, were affected at 3 mg/kg. On the 5-CSRTT, omissions were increased. Impairments in the rGT were not mimicked by the effects induced by satiation. Further, buspirone did not impair food-maintained responding under a progressive ratio schedule of reinforcement at any dose, suggesting that the effects of buspirone on the rGT cannot be explained by non-selective actions. CONCLUSIONS Although buspirone had effects on the rGT at the dose that selectively occupied the DRD3, the effects found do not parallel those found in previous studies of the effects of selective DRD3 antagonists on the rGT. Thus, buspirone may impair performance on the rGT through actions at multiple receptor sites.
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Affiliation(s)
- Patricia Di Ciano
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health (CAMH), University of Toronto, 33 Russell Street, Toronto, M5S 2S1, Canada
| | | | - Cristiana Stefan
- Clinical Laboratory and Diagnostic Services, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Ernest Wong
- Clinical Laboratory and Diagnostic Services, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Aaron Kim
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health (CAMH), University of Toronto, 33 Russell Street, Toronto, M5S 2S1, Canada
| | - Gary Remington
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health (CAMH), University of Toronto, 33 Russell Street, Toronto, M5S 2S1, Canada
- Addiction Medicine Service, Acute Care Program, CAMH, Toronto, ON, Canada
- CAMH, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
- Division of Brain and Therapeutics, Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Bernard Le Foll
- Translational Addiction Research Laboratory, Centre for Addiction and Mental Health (CAMH), University of Toronto, 33 Russell Street, Toronto, M5S 2S1, Canada.
- Addiction Medicine Service, Acute Care Program, CAMH, Toronto, ON, Canada.
- CAMH, Campbell Family Mental Health Research Institute, Toronto, ON, Canada.
- Department of Family and Community Medicine, University of Toronto, Toronto, ON, Canada.
- Department of Pharmacology, University of Toronto, Toronto, ON, Canada.
- Division of Brain and Therapeutics, Department of Psychiatry, University of Toronto, Toronto, ON, Canada.
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.
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15
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Ng KP, Pascoal TA, Mathotaarachchi S, Therriault J, Kang MS, Shin M, Guiot MC, Guo Q, Harada R, Comley RA, Massarweh G, Soucy JP, Okamura N, Gauthier S, Rosa-Neto P. Monoamine oxidase B inhibitor, selegiline, reduces 18F-THK5351 uptake in the human brain. ALZHEIMERS RESEARCH & THERAPY 2017; 9:25. [PMID: 28359327 PMCID: PMC5374697 DOI: 10.1186/s13195-017-0253-y] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/01/2017] [Indexed: 01/19/2023]
Abstract
Background 18F-THK5351 is a quinoline-derived tau imaging agent with high affinity to paired helical filaments (PHF). However, high levels of 18F-THK5351 retention in brain regions thought to contain negligible concentrations of PHF raise questions about the interpretation of the positron emission tomography (PET) signals, particularly given previously described interactions between quinolone derivatives and monoamine oxidase B (MAO-B). Here, we tested the effects of MAO-B inhibition on 18F-THK5351 brain uptake using PET and autoradiography. Methods Eight participants (five mild cognitive impairment, two Alzheimer’s disease, and one progressive supranuclear palsy) had baseline 18F-AZD4694 and 18F-THK5351 scans in order to quantify brain amyloid and PHF load, respectively. A second 18F-THK5351 scan was conducted 1 week later, 1 h after a 10-mg oral dose of selegiline. Three out of eight patients also had a third 18F-THK5351 scan 9–28 days after the selegiline administration. The primary outcome measure was standardized uptake value (SUV), calculated using tissue radioactivity concentration from 50 to 70 min after 18F-THK5351 injection, normalizing for body weight and injected radioactivity. The SUV ratio (SUVR) was determined using the cerebellar cortex as the reference region. 18F-THK5351 competition autoradiography studies in postmortem tissue were conducted using 150 and 500 nM selegiline. Results At baseline, 18F-THK5351 SUVs were highest in the basal ganglia (0.64 ± 0.11) and thalamus (0.62 ± 0.14). In the post-selegiline scans, the regional SUVs were reduced on average by 36.7% to 51.8%, with the greatest reduction noted in the thalamus (51.8%) and basal ganglia (51.4%). MAO-B inhibition also reduced 18F-THK5351 SUVs in the cerebellar cortex (41.6%). The SUVs remained reduced in the three patients imaged at 9–28 days. Tissue autoradiography confirmed the effects of MAO-B inhibition on 18F-THK5351 uptake. Conclusions These results indicate that the interpretation of 18F-THK5351 PET images, with respect to tau, is confounded by the high MAO-B availability across the entire brain. In addition, the heterogeneous MAO-B availability across the cortex may limit the interpretation of 18F-THK5351 scans using reference region methods.
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Affiliation(s)
- Kok Pin Ng
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada.,Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore.,Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Tharick A Pascoal
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Sulantha Mathotaarachchi
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Joseph Therriault
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Min Su Kang
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Monica Shin
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Marie-Christine Guiot
- Montreal Neurological Institute/Hospital, Department of Pathology, McGill University Hospital Centre, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Qi Guo
- AbbVie Inc., 1 North Waukegan Road, North Chicago, IL, USA
| | - Ryuichi Harada
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | | | - Gassan Massarweh
- McConnell Brain Imaging Centre, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Jean-Paul Soucy
- McConnell Brain Imaging Centre, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Nobuyuki Okamura
- Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, 981-8558, Japan
| | - Serge Gauthier
- Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada. .,Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada. .,Montreal Neurological Institute, 3801 University Street, Montreal, Québec, H3A 2B4, Canada. .,Department of Neurology and Neurosurgery, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada.
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16
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Mukherjee J, Constantinescu CC, Hoang AT, Jerjian T, Majji D, Pan ML. Dopamine D3 receptor binding of (18)F-fallypride: Evaluation using in vitro and in vivo PET imaging studies. Synapse 2015; 69:577-91. [PMID: 26422464 DOI: 10.1002/syn.21867] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 08/25/2015] [Accepted: 09/19/2015] [Indexed: 12/17/2022]
Abstract
Identification of dopamine D3 receptors (D3R) in vivo is important to understand several brain functions related to addiction. The goal of this work was to identify D3R binding of the dopamine D2 receptor (D2R)/D3R imaging agent, (18)F-fallypride. Brain slices from male Sprague-Dawley rats (n = 6) and New Zealand White rabbits (n = 6) were incubated with (18)F-fallypride and D3R selective agonist (R)-7-OH-DPAT (98-fold D3R selective). Rat slices were also treated with BP 897 (68-fold D3R selective partial agonist) and NGB 2904 (56-fold D3R selective antagonist). In vivo rat studies (n = 6) were done on Inveon PET using 18-37 MBq (18)F-fallypride and drug-induced displacement by (R)-7-OH-DPAT, BP 897 and NGB 2904. PET/CT imaging of wild type (WT, n = 2) and D2R knock-out (KO, n = 2) mice were carried out with (18)F-fallypride. (R)-7-OH-DPAT displaced binding of (18)F-fallypride, both in vitro and in vivo. In vitro, at 10 nM (R)-7-OH-DPAT, (18)F-fallypride binding in the rat ventral striatum (VST) and dorsal striatum (DST) and rabbit nucleus accumbens were reduced by ∼10-15%. At 10 μM (R)-7-OH-DPAT all regions in rat and rabbit were reduced by ≥85%. In vivo reductions for DST and VST before and after (R)-7-OH-DPAT were: low-dose (0.015 mg kg(-1)) DST -22%, VST -29%; high-dose (1.88 mg kg(-1)) DST -58%, VST -77%, suggesting D3R/D2R displacement. BP 897 and NGB 2904 competed with (18)F-fallypride in vitro, but unlike BP 897, NGB 2904 did not displace (18)F-fallypride in vivo. The D2R KO mice lacked (18)F-fallypride binding in the DST. In summary, our findings suggest that up to 20% of (18)F-fallypride may be bound to D3R sites in vivo.
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Affiliation(s)
- Jogeshwar Mukherjee
- Department of Radiological Sciences, Preclinical Imaging, University of California, Irvine, California, 92697
| | - Cristian C Constantinescu
- Department of Radiological Sciences, Preclinical Imaging, University of California, Irvine, California, 92697
| | - Angela T Hoang
- Department of Radiological Sciences, Preclinical Imaging, University of California, Irvine, California, 92697
| | - Taleen Jerjian
- Department of Radiological Sciences, Preclinical Imaging, University of California, Irvine, California, 92697
| | - Divya Majji
- Department of Radiological Sciences, Preclinical Imaging, University of California, Irvine, California, 92697
| | - Min-Liang Pan
- Department of Radiological Sciences, Preclinical Imaging, University of California, Irvine, California, 92697
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17
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Baba S, Enomoto T, Horisawa T, Hashimoto T, Ono M. Blonanserin extensively occupies rat dopamine D3 receptors at antipsychotic dose range. J Pharmacol Sci 2015; 127:326-31. [PMID: 25837930 DOI: 10.1016/j.jphs.2015.01.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 01/04/2015] [Accepted: 01/22/2015] [Indexed: 12/14/2022] Open
Abstract
Antagonism of the dopamine D3 receptor has been hypothesized to be beneficial for schizophrenia cognitive deficits, negative symptoms and extrapyramidal symptoms. However, recent animal and human studies have shown that most antipsychotics do not occupy D3 receptors in vivo, despite their considerable binding affinity for this receptor in vitro. In the present study, we investigated the D3 receptor binding of blonanserin, a dopamine D2/D3 and serotonin 5-HT2A receptors antagonist, in vitro and in vivo. Blonanserin showed the most potent binding affinity for human D3 receptors among the tested atypical antipsychotics (risperidone, olanzapine and aripiprazole). Our GTPγS-binding assay demonstrated that blonanserin acts as a potent full antagonist for human D3 receptors. All test-drugs exhibited antipsychotic-like efficacy in methamphetamine-induced hyperactivity in rats. Treatment with blonanserin at its effective dose blocked the binding of [(3)H]-(+)-PHNO, a D2/D3 receptor radiotracer, both in the D2 receptor-rich region (striatum) and the D3 receptor-rich region (cerebellum lobes 9 and 10). On the other hand, the occupancies of other test-drugs for D3 receptors were relatively low. In conclusion, we have shown that blonanserin, but not other tested antipsychotics, extensively occupies D3 receptors in vivo in rats.
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Affiliation(s)
- Satoko Baba
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 33-94 Enoki-cho, Suita, Osaka 564-0053, Japan
| | - Takeshi Enomoto
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 33-94 Enoki-cho, Suita, Osaka 564-0053, Japan.
| | - Tomoko Horisawa
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 33-94 Enoki-cho, Suita, Osaka 564-0053, Japan
| | - Takashi Hashimoto
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 33-94 Enoki-cho, Suita, Osaka 564-0053, Japan
| | - Michiko Ono
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 33-94 Enoki-cho, Suita, Osaka 564-0053, Japan
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Ex Vivo Characterization of a Novel Iodine-123-Labelled Aminomethylchroman as a Potential Agonist Ligand for SPECT Imaging of Dopamine D2/3 Receptors. INTERNATIONAL JOURNAL OF MOLECULAR IMAGING 2015; 2014:507012. [PMID: 25610643 PMCID: PMC4291083 DOI: 10.1155/2014/507012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 11/18/2014] [Accepted: 11/27/2014] [Indexed: 11/17/2022]
Abstract
For imaging of dopamine D2/3 receptors, agonist tracers are favoured over antagonists because they are more sensitive to detection of dopamine release and because they may selectively label the high-affinity receptor state. We have developed novel D2/3 receptor selective agonists that can be radiolabelled with [(123)I], which label is advantageous over most other labels, such as carbon-11, as it has a longer half-life. Particularly, we considered (R) N-[7-hydroxychroman-2-yl]-methyl 4-iodobenzyl amine (compound 1) as an attractive candidate for development as it shows high binding affinity to D2/3 receptors in vitro, and here we report on the characterization of this first [(123)I]-labelled D2/3 receptor agonist radiopharmaceutical intended for SPECT imaging. The appropriate tin precursor for [(123)I]-1 was developed and was successfully radiolabelled with iodine-123 giving a moderate yield (30-35%) and a good purity (>95%) for [(123)I]-1. In biodistribution experiments in Wistar rats intravenous injection of [(123)I]-1 resulted in a fast brain uptake, where the observed binding in the D2/3 receptor-rich striatum was slightly higher than that in the cerebellum 30 min to 4 h p.i. Storage phosphor imaging experiments, however, did not show specific D2/3 receptor binding. In conclusion, despite promising in vitro data for 1, neither specific ex vivo binding nor high signal-to-noise ratios were found in rodents for [(123)I]-1.
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Caravaggio F, Raitsin S, Gerretsen P, Nakajima S, Wilson A, Graff-Guerrero A. Ventral striatum binding of a dopamine D2/3 receptor agonist but not antagonist predicts normal body mass index. Biol Psychiatry 2015; 77:196-202. [PMID: 23540907 PMCID: PMC3783412 DOI: 10.1016/j.biopsych.2013.02.017] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 01/28/2013] [Accepted: 02/21/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND Positron emission tomography research has shown that dopamine D2/3 receptor (D2/3R) availability is negatively correlated with body mass index (BMI) in obese but not in healthy subjects. However, previous positron emission tomography studies have not looked specifically at the ventral striatum (VS), which plays an important role in motivation and feeding. Furthermore, these studies have only used antagonist radiotracers. Normal-weight rats given free access to high-fat diets demonstrate behavioral sensitization to D2/3R agonists but not to antagonists. Sensitization is associated with increased D2/3R affinity, which affects binding of agonists but not antagonists. METHODS We examined the association between BMI within the nonobese range (18.6-27.8) and D2/3R availability in the VS with the use of the agonist radiotracer [(11)C]-(+)-PHNO (n = 26) and the antagonist [(11)C]-raclopride (n = 35) in healthy humans. RESULTS In the VS, we found a positive correlation between BMI and [(11)C]-(+)-PHNO binding but no relationship with [(11)C]-raclopride binding. Secondary analyses revealed no relationship between BMI and binding in the dorsal striatum with either radiotracer. CONCLUSIONS We propose that in nonobese individuals, higher BMI may be associated with increased D2R affinity in the VS. This increased affinity may potentiate the incentive salience of food cues and counteract the effects of satiety cues, thereby increasing feeding.
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Affiliation(s)
- Fernando Caravaggio
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Sofia Raitsin
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Philip Gerretsen
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Shinichiro Nakajima
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Alan Wilson
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Ariel Graff-Guerrero
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
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20
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Caravaggio F, Nakajima S, Borlido C, Remington G, Gerretsen P, Wilson A, Houle S, Menon M, Mamo D, Graff-Guerrero A. Estimating endogenous dopamine levels at D2 and D3 receptors in humans using the agonist radiotracer [(11)C]-(+)-PHNO. Neuropsychopharmacology 2014; 39:2769-76. [PMID: 24874713 PMCID: PMC4200487 DOI: 10.1038/npp.2014.125] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 04/15/2014] [Accepted: 05/05/2014] [Indexed: 11/10/2022]
Abstract
Using positron emission tomography (PET) and an acute dopamine depletion challenge it is possible to estimate endogenous dopamine levels occupying dopamine D2/3 receptors (D2/3R) in humans in vivo. Our group has developed [(11)C]-(+)-PHNO, the first agonist radiotracer with preferential in vivo affinity for D3R. Thus, the use of [(11)C]-(+)-PHNO offers the novel possibility of (i) estimating in vivo endogenous dopamine levels at D2/3R using an agonist radiotracer, and (ii) estimating endogenous dopamine levels at D3R in extrastriatal regions such as the substantia nigra, hypothalamus, and ventral pallidum. Ten healthy participants underwent a [(11)C]-(+)-PHNO PET scan under baseline conditions and another under acute endogenous dopamine depletion achieved via oral administration of alpha-methyl-para-tyrosine (64 mg/kg). [(11)C]-(+)-PHNO binding was sensitive to acute dopamine depletion, allowing in vivo estimates of endogenous dopamine in D2R-rich regions (caudate and putamen), mixed D2/3R-rich regions (ventral striatum and globus pallidus), and extrastriatal D3R-rich regions (hypothalamus and ventral pallidum). Dopamine depletion decreased self-reported vigor, which was correlated with the reduction in dopamine levels in the globus pallidus. [(11)C]-(+)-PHNO is a suitable radiotracer for use in estimating endogenous dopamine levels at D2R and D3R in neuropsychiatric populations.
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Affiliation(s)
- Fernando Caravaggio
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Shinichiro Nakajima
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Carol Borlido
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Gary Remington
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Medical Science, University of Toronto, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Philip Gerretsen
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Medical Science, University of Toronto, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Alan Wilson
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Medical Science, University of Toronto, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Sylvain Houle
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Mahesh Menon
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - David Mamo
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Ariel Graff-Guerrero
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Medical Science, University of Toronto, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Research Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Toronto, ON, Canada M5T 1R8. Tel: +416 535 8501x4834, Fax: +1 416 979 3855, E-mail:
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Frederick A, Bourget-Murray J, Chapman CA, Amir S, Courtemanche R. Diurnal influences on electrophysiological oscillations and coupling in the dorsal striatum and cerebellar cortex of the anesthetized rat. Front Syst Neurosci 2014; 8:145. [PMID: 25309348 PMCID: PMC4163932 DOI: 10.3389/fnsys.2014.00145] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 07/24/2014] [Indexed: 11/18/2022] Open
Abstract
Circadian rhythms modulate behavioral processes over a 24 h period through clock gene expression. What is largely unknown is how these molecular influences shape neural activity in different brain areas. The clock gene Per2 is rhythmically expressed in the striatum and the cerebellum and its expression is linked with daily fluctuations in extracellular dopamine levels and D2 receptor activity. Electrophysiologically, dopamine depletion enhances striatal local field potential (LFP) oscillations. We investigated if LFP oscillations and synchrony were influenced by time of day, potentially via dopamine mechanisms. To assess the presence of a diurnal effect, oscillatory power and coherence were examined in the striatum and cerebellum of rats under urethane anesthesia at four different times of day zeitgeber time (ZT1, 7, 13 and 19—indicating number of hours after lights turned on in a 12:12 h light-dark cycle). We also investigated the diurnal response to systemic raclopride, a D2 receptor antagonist. Time of day affected the proportion of LFP oscillations within the 0–3 Hz band and the 3–8 Hz band. In both the striatum and the cerebellum, slow oscillations were strongest at ZT1 and weakest at ZT13. A 3–8 Hz oscillation was present when the slow oscillation was lowest, with peak 3–8 Hz activity occurring at ZT13. Raclopride enhanced the slow oscillations, and had the greatest effect at ZT13. Within the striatum and with the cerebellum, 0–3 Hz coherence was greatest at ZT1, when the slow oscillations were strongest. Coherence was also affected the most by raclopride at ZT13. Our results suggest that neural oscillations in the cerebellum and striatum, and the synchrony between these areas, are modulated by time of day, and that these changes are influenced by dopamine manipulation. This may provide insight into how circadian gene transcription patterns influence network electrophysiology. Future experiments will address how these network alterations are linked with behavior.
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Affiliation(s)
- Ariana Frederick
- Center for Studies in Behavioral Neurobiology/FRQS Groupe de Recherche en Neurobiologie Comportementale, Concordia University Montreal, QC, Canada ; Department of Biology, Concordia University Montreal, QC, Canada
| | - Jonathan Bourget-Murray
- Center for Studies in Behavioral Neurobiology/FRQS Groupe de Recherche en Neurobiologie Comportementale, Concordia University Montreal, QC, Canada ; M.D., C.M. Program, Faculty of Medicine, McGill University Montreal, QC, Canada
| | - C Andrew Chapman
- Center for Studies in Behavioral Neurobiology/FRQS Groupe de Recherche en Neurobiologie Comportementale, Concordia University Montreal, QC, Canada ; Department of Psychology, Concordia University Montreal, QC, Canada
| | - Shimon Amir
- Center for Studies in Behavioral Neurobiology/FRQS Groupe de Recherche en Neurobiologie Comportementale, Concordia University Montreal, QC, Canada ; Department of Psychology, Concordia University Montreal, QC, Canada
| | - Richard Courtemanche
- Center for Studies in Behavioral Neurobiology/FRQS Groupe de Recherche en Neurobiologie Comportementale, Concordia University Montreal, QC, Canada ; Department of Exercise Science, Concordia University Montreal, QC, Canada
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Le Foll B, Wilson AA, Graff A, Boileau I, Di Ciano P. Recent methods for measuring dopamine D3 receptor occupancy in vivo: importance for drug development. Front Pharmacol 2014; 5:161. [PMID: 25071579 PMCID: PMC4090596 DOI: 10.3389/fphar.2014.00161] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Accepted: 06/19/2014] [Indexed: 01/09/2023] Open
Abstract
There is considerable interest in developing highly selective dopamine (DA) D3 receptor ligands for a variety of mental health disorders. DA D3 receptors have been implicated in Parkinson's disease, schizophrenia, anxiety, depression, and substance use disorders. The most concrete evidence suggests a role for the D3 receptor in drug-seeking behaviors. D3 receptors are a subtype of D2 receptors, and traditionally the functional role of these two receptors has been difficult to differentiate. Over the past 10-15 years a number of compounds selective for D3 over D2 receptors have been developed. However, translating these findings into clinical research has been difficult as many of these compounds cannot be used in humans. Therefore, the functional data involving the D3 receptor in drug addiction mostly comes from pre-clinical studies. Recently, with the advent of [(11)C]-(+)-PHNO, it has become possible to image D3 receptors in the human brain with increased selectivity and sensitivity. This is a significant innovation over traditional methods such as [(11)C]-raclopride that cannot differentiate between D2 and D3 receptors. The use of [(11)C]-(+)-PHNO will allow for further delineation of the role of D3 receptors. Here, we review recent evidence that the role of the D3 receptor has functional importance and is distinct from the role of the D2 receptor. We then introduce the utility of analyzing [(11)C]-(+)-PHNO binding by region of interest. This novel methodology can be used in pre-clinical and clinical approaches for the measurement of occupancy of both D3 and D2 receptors. Evidence that [(11)C]-(+)-PHNO can provide insights into the function of D3 receptors in addiction is also presented.
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Affiliation(s)
- Bernard Le Foll
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health Toronto, ON, Canada ; Alcohol Research and Treatment Clinic, Addiction Medicine Services, Ambulatory Care and Structured Treatments, Centre for Addiction and Mental Health Toronto, ON, Canada ; Department of Family and Community Medicine, University of Toronto Toronto, ON, Canada ; Department of Pharmacology, University of Toronto Toronto, ON, Canada ; Division of Brain and Therapeutics, Department of Psychiatry, University of Toronto Toronto, ON, Canada ; Institute of Medical Sciences, University of Toronto Toronto, ON, Canada
| | - Alan A Wilson
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health Toronto, ON, Canada ; Division of Brain and Therapeutics, Department of Psychiatry, University of Toronto Toronto, ON, Canada ; Research Imaging Centre, Centre for Addiction and Mental Health Toronto, ON, Canada
| | - Ariel Graff
- Division of Brain and Therapeutics, Department of Psychiatry, University of Toronto Toronto, ON, Canada ; Research Imaging Centre, Centre for Addiction and Mental Health Toronto, ON, Canada ; Multimodal Imaging Group, Research Imaging Centre, Centre for Addiction and Mental Health Toronto, ON, Canada
| | - Isabelle Boileau
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health Toronto, ON, Canada ; Division of Brain and Therapeutics, Department of Psychiatry, University of Toronto Toronto, ON, Canada ; Institute of Medical Sciences, University of Toronto Toronto, ON, Canada ; Research Imaging Centre, Centre for Addiction and Mental Health Toronto, ON, Canada ; Addiction Imaging Research Group, Centre for Addiction and Mental Health Toronto, ON, Canada
| | - Patricia Di Ciano
- Translational Addiction Research Laboratory, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health Toronto, ON, Canada
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Liang SL, Hsu SC, Pan JT. Involvement of dopamine D2 receptor in the diurnal changes of tuberoinfundibular dopaminergic neuron activity and prolactin secretion in female rats. J Biomed Sci 2014; 21:37. [PMID: 24884386 PMCID: PMC4019350 DOI: 10.1186/1423-0127-21-37] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 04/29/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND An endogenous dopaminergic (DA) tone acting on D3 receptors has been shown to inhibit tuberoinfundibular (TI) DA neuron activity and stimulate prolactin (PRL) surge in the afternoon of estrogen-primed ovariectomized (OVX+E2) rats. Whether D2 receptor (D2R) is also involved in the regulation of TIDA and PRL rhythms was determined in this study. RESULTS Intracerebroventricular (icv) injection of PHNO, a D2R agonist, in the morning inhibited TIDA and midbrain DA neurons' activities, and stimulated PRL secretion. The effects of PHNO were significantly reversed by co-administration of raclopride, a D2R antagonist. A single injection of raclopride at 1200 h significantly reversed the lowered TIDA neuron activity and the increased serum PRL level at 1500 h. Dopamine D2R mRNA expression in medial basal hypothalamus (MBH) exhibited a diurnal rhythm, i.e., low in the morning and high in the afternoon, which was opposite to that of TIDA neuron activity. The D2R rhythm was abolished in OVX+E2 rats kept under constant lighting but not in OVX rats with regular lighting exposures. Pretreatment with an antisense oligodeoxynucleotides (AODN, 10 μg/3 μl/day, icv) against D2R mRNA for 2 days significantly reduced D2R mRNAs in central DA neurons, and reversed both lowered TIDA neuron activity and increased serum PRL level in the afternoon on day 3. A diurnal rhythm of D2R mRNA expression was also observed in midbrain DA neurons and the rhythm was significantly knocked down by the AODN pretreatment. CONCLUSIONS We conclude that a diurnal change of D2R mRNA expression in MBH may underlie the diurnal rhythms of TIDA neuron activity and PRL secretion in OVX+E2 rats.
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Affiliation(s)
- Shu-Ling Liang
- Department of Physiology and Pharmacology, College of Medicine, Chang Gung University, Tao-Yuan 33302, Taiwan.
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Shimizu S, Tatara A, Sato M, Sugiuchi T, Miyoshi S, Andatsu S, Kizu T, Ohno Y. Role of cerebellar dopamine D(3) receptors in modulating exploratory locomotion and cataleptogenicity in rats. Prog Neuropsychopharmacol Biol Psychiatry 2014; 50:157-62. [PMID: 24368396 DOI: 10.1016/j.pnpbp.2013.12.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 12/04/2013] [Accepted: 12/17/2013] [Indexed: 11/17/2022]
Abstract
Dopamine D(3) receptors are highly expressed in the cerebellum; however, their pathophysiological functions are not fully understood. Here, we conducted microinjection studies to clarify the role of cerebellar D(3) receptors in modulating locomotion and cataleptogenicity in rats. Microinjection of the preferential D(3) agonist 7-hydroxy-N,N-di-n-propyl-2-aminotetralin (7-OH-DPAT) into lobe 9 of the cerebellum significantly reduced spontaneous locomotor activity with a U-shaped dose-response curve. The intracerebellar microinjection of 7-OH-DPAT did not elicit catalepsy by itself, but markedly potentiated catalepsy induction with a low dose (0.3mg/kg) of haloperidol. The catalepsy enhancement by 7-OH-DPAT occurred in a dose-dependent manner and was not associated with the locomotor inhibition. U-99194A (a selective D(3) antagonist) or AD-6048 (a preferential D(3) vs. D(2) antagonist) antagonized both the catalepsy enhancement and the locomotor inhibition with 7-OH-DPAT. In addition, U-99194A and AD-6048 per se significantly alleviated catalepsy induced by a high dose (0.5mg/kg) of haloperidol. Furthermore, microinjection of 7-OH-DPAT into the nucleus accumbens or the dorsolateral striatum neither affected spontaneous locomotor activity nor haloperidol (0.3mg/kg)-induced catalepsy. The present results illustrate for the first time the role of cerebellar D(3) receptors in modulating cataleptogenicity of antipsychotic agents, implying that blockade of cerebellar D(3) receptors contributes to the reduction of extrapyramidal side effects.
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Affiliation(s)
- Saki Shimizu
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Ayaka Tatara
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Maho Sato
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Tomone Sugiuchi
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Satoshi Miyoshi
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Saki Andatsu
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Tomoya Kizu
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan
| | - Yukihiro Ohno
- Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan.
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Beyond the basal ganglia: cFOS expression in the cerebellum in response to acute and chronic dopaminergic alterations. Neuroscience 2014; 267:219-31. [PMID: 24631673 DOI: 10.1016/j.neuroscience.2014.02.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Revised: 02/15/2014] [Accepted: 02/28/2014] [Indexed: 11/21/2022]
Abstract
The suggestion of an anatomical and functional relationship between the basal ganglia and cerebellum is recent. Traditionally, these structures were considered as neuronal circuits working separately to organize and control goal-directed movements and cognitive functions. However, several studies in rodents and primates have described an anatomical interaction between cortico-basal and cortico-cerebellar networks. Most importantly, functional changes have been observed in one of these circuits when altering the other one. In this context, we aimed to accomplish an extensive description of cerebellar activation patterns using cFOS expression (cFOS-IR) after acute and chronic manipulation of dopaminergic activity. In the acute study, substantia nigra pars compacta (SNc) activity was stimulated or suppressed by intra cerebral administration of picrotoxin or lidocaine, respectively. In addition, we analyzed cerebellar activity after the induction of a parkinsonism model, the tremulous jaw movements. In this model, tremulous jaw movements were induced in male rats by IP chronic administration of the dopamine antagonist haloperidol (1.5mg/kg). Acute stimulation of SNc by picrotoxin increased cFOS-IR in the vermis and cerebellar hemispheres. However, lidocaine did not produce an effect. After 14days of haloperidol treatment, the vermis and cerebellar hemispheres showed an opposite regulation of cFOS expression. Chronic dopaminergic antagonism lessened cFOS expression in the vermis but up-regulated such expression in the cerebellar hemisphere. Overall, the present data indicate a very close functional relationship between the basal ganglia and the cerebellum and they may allow a better understanding of disorders in which there are dopamine alterations.
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Micheli F, Heidbreder C. Dopamine D3 receptor antagonists: a patent review (2007 - 2012). Expert Opin Ther Pat 2013; 23:363-81. [PMID: 23282131 DOI: 10.1517/13543776.2013.757593] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
INTRODUCTION The synthesis and characterization of new highly potent and selective dopamine (DA) D3 receptor antagonists has permitted to characterize the role of the DA D3 receptor in the control of drug-seeking behavior and in the pathophysiology of impulse control disorders and schizophrenia. AREAS COVERED In the present review, the authors will first describe most recent classes of DA D3 receptor antagonists by reviewing about 43 patent applications during the 2007 - 2012 period; they will then outline the biological rationale in support of the use of selective DA D3 receptor antagonists in the treatment of drug addiction, impulse control disorders and schizophrenia. EXPERT OPINION The strongest clinical application and potential for selective DA D3 receptor antagonists lies in the reduction of drug-induced incentive motivation, the attenuation of drug's rewarding efficacy and the reduction in reinstatement of drug-seeking behavior triggered either by re-exposure to the drug itself, re-exposure to environmental cues that had been previously associated with drug-taking behavior or stress. The selectivity of these antagonists together with reduced lipophilicity (minimizing unspecific binding), increased brain penetration and improved physico-chemical profile are all key factors for clinical efficacy and safety.
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Affiliation(s)
- Fabrizio Micheli
- Drug Design & Discovery, Aptuit Verona srl, Via A Fleming 4, 37135 Verona, Italy.
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Barth V, Need AB, Tzavara ET, Giros B, Overshiner C, Gleason SD, Wade M, Johansson AM, Perry K, Nomikos GG, Witkin JM. In vivo occupancy of dopamine D3 receptors by antagonists produces neurochemical and behavioral effects of potential relevance to attention-deficit-hyperactivity disorder. J Pharmacol Exp Ther 2012. [PMID: 23197772 DOI: 10.1124/jpet.112.198895] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Dopamine D(3) receptors have eluded definitive linkage to neurologic and psychiatric disorders since their cloning over 20 years ago. We report a new method that does not employ a radiolabel for simultaneously defining in vivo receptor occupancy of D(3) and D(2) receptors in rat brain after systemic dosing using the tracer epidepride (N-[[(2S)-1-ethylpyrrolidin-2-yl]methyl]-5-iodo-2,3-dimethoxybenzamide). Decreases in epidepride binding in lobule 9 of cerebellum (rich in D(3) receptors) were compared with nonspecific binding in the lateral cerebellum. The in vivo occupancy of the dopamine D(3) receptors was dose dependently increased by SB-277011A (trans-N-[4-[2-(6-cyano-1,2,3,4-tetrahydroisoquinolin-2-yl)ethyl]cyclohexyl]-4-quinolinecarboxamide) and U99194 (2,3-dihydro-5,6-dimethoxy- N,N-dipropyl-1H-inden-2-amine). Both antagonists increased extracellular levels of acetylcholine (ACh) in the medial prefrontal cortex of rats and modified brain-tissue levels of ACh and choline. Consistent with these findings, the D(3) receptor antagonists enhanced the acquisition of learning of rats either alone or in the presence of the norepinephrine uptake blocker reboxetine as with the attention-deficit-hyperactivity disorder (ADHD) drug methylphenidate. Like reboxetine, the D(3) receptor antagonists also prevented deficits induced by scopolamine in object recognition memory of rats. Mice in which the dopamine transporter (DAT) has been deleted exhibit hyperactivity that is normalized by compounds that are effective in the treatment of ADHD. Both D(3) receptor antagonists decreased the hyperactivity of DAT(-/-) mice without affecting the activity of wild type controls. The present findings indicate that dopamine D(3) receptor antagonists engender cognition-enhancing and hyperactivity-dampening effects. Thus, D(3) receptor blockade could be considered as a novel treatment approach for cognitive deficits and hyperactivity syndromes, including those observed in ADHD.
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Affiliation(s)
- V Barth
- Psychiatric Drug Discovery, Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, IN 46285-0501, USA
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Heidbreder C. Rationale in support of the use of selective dopamine D₃ receptor antagonists for the pharmacotherapeutic management of substance use disorders. Naunyn Schmiedebergs Arch Pharmacol 2012; 386:167-76. [PMID: 23104235 DOI: 10.1007/s00210-012-0803-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 10/15/2012] [Indexed: 10/27/2022]
Abstract
Growing evidence indicates that dopamine (DA) D(3) receptors are involved in the control of drug-seeking behavior and may play an important role in the pathophysiology of substance use disorders. First, DA D(3) receptors are distributed in strategic areas belonging to the mesolimbic DA system such as the ventral striatum, midbrain, and pallidum, which have been associated with behaviors controlled by the presentation of drug-associated cues. Second, repeated exposure to drugs of abuse has been shown to produce neuroadaptations in the DA D(3) system. Third, the synthesis and characterization of highly potent and selective DA D(3) receptor antagonists has permitted to further define the role of the DA D(3) receptor in drug addiction. Provided that the available preclinical and preliminary clinical evidence can be translated into clinical proof of concept in human, selective DA D(3) receptor antagonists show promise for the treatment of substance use disorders as reflected by their potential to (1) regulate the motivation to self-administered drugs under schedules of reinforcement that require an increase in work demand and (2) disrupt the responsiveness to drug-associated stimuli that play a key role in the reinstatement of drug-seeking behavior triggered by re-exposure to the drug itself, re-exposure to environmental cues that had been previously associated with drug-taking behavior, or stress.
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Affiliation(s)
- Christian Heidbreder
- Reckitt Benckiser Pharmaceuticals-Global Research and Development, 10710 Midlothian Turnpike Suite 430, Richmond, VA 23235, USA.
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Cariprazine (RGH-188), a potent D3/D2 dopamine receptor partial agonist, binds to dopamine D3 receptors in vivo and shows antipsychotic-like and procognitive effects in rodents. Neurochem Int 2011; 59:925-35. [PMID: 21767587 DOI: 10.1016/j.neuint.2011.07.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 06/24/2011] [Accepted: 07/01/2011] [Indexed: 11/22/2022]
Abstract
We investigated the in vivo effects of orally administered cariprazine (RGH-188; trans-N-{4-[2-[4-(2,3-dichlorophenyl)-piperazin-1-yl]-ethyl]-cyclohexyl}-N',N'-dimethyl-urea), a D(3)/D(2) dopamine receptor partial agonist with ∼10-fold preference for the D(3) receptor. Oral bioavailability of cariprazine at a dose of 1mg/kg in rats was 52% with peak plasma concentrations of 91ng/mL. Cariprazine 10mg/kg had good blood-brain barrier penetration, with a brain/plasma AUC ratio of 7.6:1. In rats, cariprazine showed dose-dependent in vivo displacement of [(3)H](+)-PHNO, a dopamine D(3) receptor-preferring radiotracer, in the D(3) receptor-rich region of cerebellar lobules 9 and 10. Its potent inhibition of apomorphine-induced climbing in mice (ED(50)=0.27mg/kg) was sustained for 8h. Cariprazine blocked amphetamine-induced hyperactivity (ED(50)=0.12mg/kg) and conditioned avoidance response (CAR) (ED(50)=0.84mg/kg) in rats, and inhibited the locomotor-stimulating effects of the noncompetitive NMDA antagonists MK-801 (ED(50)=0.049mg/kg) and phencyclidine (ED(50)=0.09mg/kg) in mice and rats, respectively. It reduced novelty-induced motor activity of mice (ED(50)=0.11mg/kg) and rats (ED(50)=0.18mg/kg) with a maximal effect of 70% in both species. Cariprazine produced no catalepsy in rats at up to 100-fold dose of its CAR inhibitory ED(50) value. Cariprazine 0.02-0.08mg/kg significantly improved the learning performance of scopolamine-treated rats in a water-labyrinth learning paradigm. Though risperidone, olanzapine, and aripiprazole showed antipsychotic-like activity in many of these assays, they were less active against phencyclidine and more cataleptogenic than cariprazine, and had no significant effect in the learning task. The distinct in vivo profile of cariprazine may be due to its higher affinity and in vivo binding to D(3) receptors versus currently marketed typical and atypical antipsychotics.
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