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Wong TS, Li G, Li S, Gao W, Chen G, Gan S, Zhang M, Li H, Wu S, Du Y. G protein-coupled receptors in neurodegenerative diseases and psychiatric disorders. Signal Transduct Target Ther 2023; 8:177. [PMID: 37137892 PMCID: PMC10154768 DOI: 10.1038/s41392-023-01427-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 02/17/2023] [Accepted: 03/30/2023] [Indexed: 05/05/2023] Open
Abstract
Neuropsychiatric disorders are multifactorial disorders with diverse aetiological factors. Identifying treatment targets is challenging because the diseases are resulting from heterogeneous biological, genetic, and environmental factors. Nevertheless, the increasing understanding of G protein-coupled receptor (GPCR) opens a new possibility in drug discovery. Harnessing our knowledge of molecular mechanisms and structural information of GPCRs will be advantageous for developing effective drugs. This review provides an overview of the role of GPCRs in various neurodegenerative and psychiatric diseases. Besides, we highlight the emerging opportunities of novel GPCR targets and address recent progress in GPCR drug development.
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Affiliation(s)
- Thian-Sze Wong
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
- School of Medicine, Tsinghua University, 100084, Beijing, China
| | - Guangzhi Li
- Institute of Urology, The Affiliated Luohu Hospital of Shenzhen University, Shenzhen University, 518000, Shenzhen, Guangdong, China
| | - Shiliang Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 200237, Shanghai, China
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China
| | - Wei Gao
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China
| | - Geng Chen
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
| | - Shiyi Gan
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China
| | - Manzhan Zhang
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 200237, Shanghai, China
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China
| | - Honglin Li
- Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, 200237, Shanghai, China.
- Innovation Center for AI and Drug Discovery, East China Normal University, 200062, Shanghai, China.
| | - Song Wu
- Institute of Urology, The Affiliated Luohu Hospital of Shenzhen University, Shenzhen University, 518000, Shenzhen, Guangdong, China.
- Department of Urology, South China Hospital, Health Science Center, Shenzhen University, 518116, Shenzhen, Guangdong, China.
| | - Yang Du
- Kobilka Institute of Innovative Drug Discovery, Shenzhen Key Laboratory of Steroid Drug Discovery and Development, School of Medicine, The Chinese University of Hong Kong, 518172, Shenzhen, Guangdong, China.
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Tamaian R, Porozov Y, Shityakov S. Exhaustive in silico design and screening of novel antipsychotic compounds with improved pharmacodynamics and blood-brain barrier permeation properties. J Biomol Struct Dyn 2023; 41:14849-14870. [PMID: 36927517 DOI: 10.1080/07391102.2023.2184179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 02/18/2023] [Indexed: 03/18/2023]
Abstract
Antipsychotic drugs or neuroleptics are widely used in the treatment of psychosis as a manifestation of schizophrenia and bipolar disorder. However, their effectiveness largely depends on the blood-brain barrier (BBB) permeation (pharmacokinetics) and drug-receptor pharmacodynamics. Therefore, in this study, we developed and implemented the in silico pipeline to design novel compounds (n = 260) as leads using the standard drug scaffolds with improved PK/PD properties from the standard scaffolds. As a result, the best candidates (n = 3) were evaluated in molecular docking to interact with serotonin and dopamine receptors. Finally, haloperidol (HAL) derivative (1-(4-fluorophenyl)-4-(4-hydroxy-4-{4-[(2-phenyl-1,3-thiazol-4-yl)methyl]phenyl}piperidin-1-yl)butan-1-one) was identified as a "magic shotgun" lead compound with better affinity to the 5-HT2A, 5-HT1D, D2, D3, and 5-HT1B receptors than the control molecule. Additionally, this hit substance was predicted to possess similar BBB permeation properties and much lower toxicological profiles in comparison to HAL. Overall, the proposed rational drug design platform for novel antipsychotic drugs based on the BBB permeation and receptor binding might be an invaluable asset for a medicinal chemist or translational pharmacologist.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Radu Tamaian
- ICSI Analytics, National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Vâlcea, Râmnicu Vâlcea, Romania
| | - Yuri Porozov
- Center of Bio- and Chemoinformatics, I.M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Sergey Shityakov
- Laboratory of Chemoinformatics, Infochemistry Scientific Center, ITMO University, Saint-Petersburg, Russia
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3
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Fu H, Rong J, Chen Z, Zhou J, Collier T, Liang SH. Positron Emission Tomography (PET) Imaging Tracers for Serotonin Receptors. J Med Chem 2022; 65:10755-10808. [PMID: 35939391 DOI: 10.1021/acs.jmedchem.2c00633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) and 5-HT receptors (5-HTRs) have crucial roles in various neuropsychiatric disorders and neurodegenerative diseases, making them attractive diagnostic and therapeutic targets. Positron emission tomography (PET) is a noninvasive nuclear molecular imaging technique and is an essential tool in clinical diagnosis and drug discovery. In this context, numerous PET ligands have been developed for "visualizing" 5-HTRs in the brain and translated into human use to study disease mechanisms and/or support drug development. Herein, we present a comprehensive repertoire of 5-HTR PET ligands by focusing on their chemotypes and performance in PET imaging studies. Furthermore, this Perspective summarizes recent 5-HTR-focused drug discovery, including biased agonists and allosteric modulators, which would stimulate the development of more potent and subtype-selective 5-HTR PET ligands and thus further our understanding of 5-HTR biology.
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Affiliation(s)
- Hualong Fu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Jian Rong
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114, United States.,Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Zhen Chen
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing, Jiangsu 210037, China
| | - Jingyin Zhou
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Thomas Collier
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114, United States.,Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Steven H Liang
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114, United States.,Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115, United States
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Shi M, Tang J, Yang C, Guo G, Ou H, Chen W. Pimavanserin, a 5-hydroxytryptamine 2A receptor inverse agonist, reverses prepulse inhibition deficits in the nucleus accumbens and ventral hippocampus. Neuropharmacology 2021; 201:108838. [PMID: 34666074 DOI: 10.1016/j.neuropharm.2021.108838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 10/09/2021] [Accepted: 10/11/2021] [Indexed: 10/20/2022]
Abstract
Prepulse inhibition (PPI) is disrupted in many neuropsychiatric diseases. Although the inverse agonist of the 5-hydroxytryptamine 2A (5-HT2A) receptors, pimavanserin, alleviates PPI deficits in rodents, the precise mechanisms and critical brain areas in the reversal effect of 5-HT2A receptor inverse agonists remain unclear. The present study aimed to investigate the critical brain areas responsible for the reversal effect of the 5-HT2A receptor inverse agonist on PPI deficits in male mice. The results showed that intraperitoneal administration of pimavanserin was found to improve normal PPI behavior and reverse PPI deficits elicited by the dopamine D1/D2 receptor nonselective agonist, pergolide. Further, local infusion of pimavanserin into the nucleus accumbens and ventral hippocampus reversed PPI deficits, whereas the same manipulation in the medial prefrontal cortex or ventral tegmental area did not reverse PPI deficits. Overall, the nucleus accumbens and ventral hippocampus are the critical brain areas responsible for the reversal effect of 5-HT2A inverse agonists on PPI deficits. Such findings contribute to the extensive exploration of the accurate molecular and neural mechanisms underlying the antipsychotic effects of 5-HT2A receptor inverse agonists, especially the neural circuits modulated by 5-HT2A receptor activity.
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Affiliation(s)
- Mengwen Shi
- Key Laboratory of Cognition and Personality Southwest University, Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Jiaxin Tang
- Key Laboratory of Cognition and Personality Southwest University, Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Chengmei Yang
- Key Laboratory of Cognition and Personality Southwest University, Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Guanlong Guo
- Key Laboratory of Cognition and Personality Southwest University, Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Huaxing Ou
- Key Laboratory of Cognition and Personality Southwest University, Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China
| | - Weihai Chen
- Key Laboratory of Cognition and Personality Southwest University, Ministry of Education, Chongqing, China; Faculty of Psychology, Southwest University, Chongqing, China.
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Sholler DJ, Stutz SJ, Fox RG, Boone EL, Wang Q, Rice KC, Moeller FG, Anastasio NC, Cunningham KA. The 5-HT 2A Receptor (5-HT 2AR) Regulates Impulsive Action and Cocaine Cue Reactivity in Male Sprague-Dawley Rats. J Pharmacol Exp Ther 2019; 368:41-49. [PMID: 30373886 PMCID: PMC6290084 DOI: 10.1124/jpet.118.251199] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 10/25/2018] [Indexed: 01/25/2023] Open
Abstract
Impulsivity and the attentional orienting response to cocaine-associated cues (cue reactivity) promote relapse in cocaine-use disorder (CUD). A time-dependent escalation of cue reactivity (incubation) occurs during extended, forced abstinence from cocaine self-administration in rats. The investigational serotonin (5-HT) 5-HT2A receptor (5-HT2AR) antagonist/inverse agonist M100907 suppresses impulsive action, or the inability to withhold premature responses, and cocaine-seeking behaviors. The present preclinical study was designed to establish the potential for repurposing the Food and Drug Administration-approved selective 5-HT2AR antagonist/inverse agonist pimavanserin as a therapeutic agent to forestall relapse vulnerability in CUD. In male Sprague-Dawley rats, pimavanserin suppressed impulsive action (premature responses) measured in the 1-choice serial reaction time (1-CSRT) task, similarly to M100907. We also used the 1-CSRT task to establish baseline levels of impulsive action before cocaine self-administration and evaluation of cue reactivity (lever presses reinforced by the discrete cue complex previously paired with cocaine delivery). We observed an incubation of cocaine cue reactivity between day 1 and day 30 of forced abstinence from cocaine self-administration. Baseline levels of impulsive action predicted incubated levels of cocaine cue reactivity in late abstinence. We also found that baseline impulsive action predicted the effectiveness of pimavanserin to suppress incubated cue reactivity in late abstinence from cocaine self-administration at doses that were ineffective in early abstinence. These data suggest that integration of clinical measures of impulsive action may inform refined, personalized pharmacotherapeutic intervention for the treatment of relapse vulnerability in CUD.
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Affiliation(s)
- Dennis J Sholler
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - Sonja J Stutz
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - Robert G Fox
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - Edward L Boone
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - Qin Wang
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - Kenner C Rice
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - F Gerard Moeller
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - Noelle C Anastasio
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
| | - Kathryn A Cunningham
- Center for Addiction Research and Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas (D.J.S., S.J.S., R.G.F., N.C.A., K.A.C.); Department of Statistical Sciences and Operations Research, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (E.L.B., Q.W.); Drug Design and Synthesis Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Bethesda, Maryland (K.C.R.); and Department of Psychiatry, Institute for Drug and Alcohol Studies, Virginia Commonwealth University, Richmond, Virginia (F.G.M.)
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Guidance for switching from off-label antipsychotics to pimavanserin for Parkinson's disease psychosis: an expert consensus. CNS Spectr 2018; 23:402-413. [PMID: 30588905 DOI: 10.1017/s1092852918001359] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Patients with Parkinson's disease psychosis (PDP) are often treated with an atypical antipsychotic, especially quetiapine or clozapine, but side effects, lack of sufficient efficacy, or both may motivate a switch to pimavanserin, the first medication approved for management of PDP. How best to implement a switch to pimavanserin has not been clear, as there are no controlled trials or case series in the literature to provide guidance. An abrupt switch may interrupt partially effective treatment or potentially trigger rebound effects from antipsychotic withdrawal, whereas cross-taper involves potential drug interactions. A panel of experts drew from published data, their experience treating PDP, lessons from switching antipsychotic drugs in other populations, and the pharmacology of the relevant drugs, to establish consensus recommendations. The panel concluded that patients with PDP can be safely and effectively switched from atypical antipsychotics used off label in PDP to the recently approved pimavanserin by considering each agent's pharmacokinetics and pharmacodynamics, receptor interactions, and the clinical reason for switching (efficacy or adverse events). Final recommendations are that such a switch should aim to maintain adequate 5-HT2A antagonism during the switch, thus providing a stable transition so that efficacy is maintained. Specifically, the consensus recommendation is to add pimavanserin at the full recommended daily dose (34 mg) for 2-6 weeks in most patients before beginning to taper and discontinue quetiapine or clozapine over several days to weeks. Further details are provided for this recommendation, as well as for special clinical circumstances where switching may need to proceed more rapidly.
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Frameworking memory and serotonergic markers. Rev Neurosci 2017; 28:455-497. [DOI: 10.1515/revneuro-2016-0079] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 01/16/2017] [Indexed: 12/29/2022]
Abstract
Abstract:The evidence for neural markers and memory is continuously being revised, and as evidence continues to accumulate, herein, we frame earlier and new evidence. Hence, in this work, the aim is to provide an appropriate conceptual framework of serotonergic markers associated with neural activity and memory. Serotonin (5-hydroxytryptamine [5-HT]) has multiple pharmacological tools, well-characterized downstream signaling in mammals’ species, and established 5-HT neural markers showing new insights about memory functions and dysfunctions, including receptors (5-HT1A/1B/1D, 5-HT2A/2B/2C, and 5-HT3-7), transporter (serotonin transporter [SERT]) and volume transmission present in brain areas involved in memory. Bidirectional influence occurs between 5-HT markers and memory/amnesia. A growing number of researchers report that memory, amnesia, or forgetting modifies neural markers. Diverse approaches support the translatability of using neural markers and cerebral functions/dysfunctions, including memory formation and amnesia. At least, 5-HT1A, 5-HT4, 5-HT6, and 5-HT7receptors and SERT seem to be useful neural markers and therapeutic targets. Hence, several mechanisms cooperate to achieve synaptic plasticity or memory, including changes in the expression of neurotransmitter receptors and transporters.
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Sullivan LC, Clarke WP, Berg KA. Atypical antipsychotics and inverse agonism at 5-HT2 receptors. Curr Pharm Des 2016; 21:3732-8. [PMID: 26044975 DOI: 10.2174/1381612821666150605111236] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 06/04/2015] [Indexed: 11/22/2022]
Abstract
It is now well accepted that receptors can regulate cellular signaling pathways in the absence of a stimulating ligand, and inverse agonists can reduce this ligand-independent or "constitutive" receptor activity. Both the serotonin 5-HT2A and 5-HT2C receptors have demonstrated constitutive receptor activity in vitro and in vivo. Each has been identified as a target for treatment of schizophrenia. Further, most, if not all, atypical antipsychotic drugs have inverse agonist properties at both 5-HT2A and 5-HT2C receptors. This paper describes our current knowledge of inverse agonism of atypical antipsychotics at 5-HT2A/2C receptor subtypes in vitro and in vivo. Exploiting inverse agonist properties of APDs may provide new avenues for drug development.
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Affiliation(s)
| | | | - Kelly A Berg
- Department of Pharmacology - MS 7764, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA.
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Abstract
Diverse neuropsychiatric disorders present dysfunctional memory and no effective treatment exits for them; likely as result of the absence of neural markers associated to memory. Neurotransmitter systems and signaling pathways have been implicated in memory and dysfunctional memory; however, their role is poorly understood. Hence, neural markers and cerebral functions and dysfunctions are revised. To our knowledge no previous systematic works have been published addressing these issues. The interactions among behavioral tasks, control groups and molecular changes and/or pharmacological effects are mentioned. Neurotransmitter receptors and signaling pathways, during normal and abnormally functioning memory with an emphasis on the behavioral aspects of memory are revised. With focus on serotonin, since as it is a well characterized neurotransmitter, with multiple pharmacological tools, and well characterized downstream signaling in mammals' species. 5-HT1A, 5-HT4, 5-HT5, 5-HT6, and 5-HT7 receptors as well as SERT (serotonin transporter) seem to be useful neural markers and/or therapeutic targets. Certainly, if the mentioned evidence is replicated, then the translatability from preclinical and clinical studies to neural changes might be confirmed. Hypothesis and theories might provide appropriate limits and perspectives of evidence.
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Affiliation(s)
- Alfredo Meneses
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Mexico City, Mexico
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Meneses A, Perez-Garcia G, Liy-Salmeron G, Ponce-López T, Lacivita E, Leopoldo M. 5-HT7 receptor activation: procognitive and antiamnesic effects. Psychopharmacology (Berl) 2015; 232:595-603. [PMID: 25074446 DOI: 10.1007/s00213-014-3693-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 07/16/2014] [Indexed: 12/31/2022]
Abstract
RATIONALE The serotonin (5-hydroxytryptamine (5-HT)) 5-HT7 receptor is localized in brain areas mediating memory; however, the role of this receptor on memory remains little explored. OBJECTIVE First, demonstrating the associative nature of Pavlovian/instrumental autoshaping (P/I-A) task, rats were exposed (three sessions) to CS-US (Pavlovian autoshaping), truly random control, free operant, and presentations of US or CS, and they were compared with rats trained-tested for one session to the P/I-A procedure. Also, effects of the 5-HT7 receptor agonist LP-211 administered intraperitoneally after training was determined on short- (1.5 h) and long-term memory 24 and 48 h) and on scopolamine-induced memory impairment and cAMP production. METHODS Autoshaping and its behavioral controls were studied. Other animals were subjected to an autoshaping training session and immediately afterwards were given (intraperitoneal) vehicle or LP-211 (0.1-10 mg/kg) and/or scopolamine (0.2 mg/kg) and tested for short-term memory (STM) and long-term memory (LTM); their brains were extracted for the cAMP ELISA immunoassay. RESULTS P/I-A group produced the higher %CR. LP-211 did not affect STM; nonetheless, at 0.5 and 1.0 mg/kg, it improved LTM. The 5-HT7 receptor antagonist SB-269970 (SB; 10.0 mg/kg) alone had no effect; nevertheless, the LP-211 (1.0 mg/kg) LTM facilitation was reversed by SB. The scopolamine (0.2 mg/kg) induced-decrement in CR was accompanied by significant increased cAMP production. The scopolamine-induced decrement in CR and increments in cAMP were significantly attenuated by LP-211. CONCLUSIONS Autoshaping is a reliable associative learning task whose consolidation is facilitated by the 5-HT7 receptor agonist LP-211.
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Affiliation(s)
- A Meneses
- Depto. de Farmacobiología, CINVESTAV-IPN, México City, México,
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On the discovery and development of pimavanserin: a novel drug candidate for Parkinson's psychosis. Neurochem Res 2014; 39:2008-17. [PMID: 24682754 PMCID: PMC4172996 DOI: 10.1007/s11064-014-1293-3] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Revised: 03/19/2014] [Accepted: 03/21/2014] [Indexed: 12/30/2022]
Abstract
Parkinson’s disease psychosis (PDP) is a condition that may develop in up to 60 % of Parkinson’s patients, and is a major reason for nursing home placement for those affected. There are no FDA approved drugs for PDP but low doses of atypical anti-psychotic drugs (APDs) are commonly prescribed off-label. Only low-dose clozapine has shown efficacy in randomized controlled trials, but all APDs have black box warnings related to the increased mortality and morbidity when used in elderly demented patients. Using molecular pharmacological profiling of a large collection of marketed drugs, we discovered that potent inverse agonist activity against 5-HT2A serotonin receptors was a common feature of atypical APDs, especially the atypical APDs used to treat PDP. Since low-dose clozapine therapy selectively blocks this receptor, it was hypothesized that a highly selective 5-HT2A receptor inverse agonist might provide good symptom control in patients suffering from PDP, with a greatly improved safety and tolerability profile. A high throughput screening and subsequent chemical lead optimization campaign to develop potent, selective 5-HT2A receptor inverse agonists was launched, eventually resulting in the discovery of pimavanserin. Pimavanserin displays nanomolar potency as a 5-HT2A receptor inverse agonist, selectivity for 5-HT2A over 5-HT2C receptors, and no meaningful activity at any other G-protein coupled receptor. It demonstrated robust activity in preclinical models of schizophrenia and PDP, and did not worsen motoric symptoms, in contrast to the APDs tested. In a Phase III clinical trial, pimavanserin showed highly significant benefits in the primary endpoint, the scale for assessment of positive symptoms-PD, a scale adapted for use in PDP. In addition, improvements in all other efficacy endpoints, including physician’s clinical global impression, caregiver burden, night-time sleep quality and daytime wakefulness, were seen. Pimavanserin demonstrated good safety and tolerability and did not worsen motoric symptoms as assessed by the unified Parkinson’s disease rating scale parts II and III. An open-label extension study has further demonstrated that pimavanserin is safe and well-tolerated with long-term use. Pimavanserin may therefore offer a viable treatment option for patients suffering from PDP.
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Canal CE, Morgan D, Felsing D, Kondabolu K, Rowland NE, Robertson KL, Sakhuja R, Booth RG. A novel aminotetralin-type serotonin (5-HT) 2C receptor-specific agonist and 5-HT2A competitive antagonist/5-HT2B inverse agonist with preclinical efficacy for psychoses. J Pharmacol Exp Ther 2014; 349:310-8. [PMID: 24563531 DOI: 10.1124/jpet.113.212373] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Development of 5-HT2C agonists for treatment of neuropsychiatric disorders, including psychoses, substance abuse, and obesity, has been fraught with difficulties, because the vast majority of reported 5-HT2C selective agonists also activate 5-HT2A and/or 5-HT2B receptors, potentially causing hallucinations and/or cardiac valvulopathy. Herein is described a novel, potent, and efficacious human 5-HT2C receptor agonist, (-)-trans-(2S,4R)-4-(3'[meta]-bromophenyl)-N,N-dimethyl-1,2,3,4-tetrahydronaphthalen-2-amine (-)-MBP), that is a competitive antagonist and inverse agonist at human 5-HT2A and 5-HT2B receptors, respectively. (-)-MBP has efficacy comparable to the prototypical second-generation antipsychotic drug clozapine in three C57Bl/6 mouse models of drug-induced psychoses: the head-twitch response elicited by [2,5]-dimethoxy-4-iodoamphetamine; hyperlocomotion induced by MK-801 [(5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (dizocilpine maleate)]; and hyperlocomotion induced by amphetamine. (-)-MBP, however, does not alter locomotion when administered alone, distinguishing it from clozapine, which suppresses locomotion. Finally, consumption of highly palatable food by mice was not increased by (-)-MBP at a dose that produced at least 50% maximal efficacy in the psychoses models. Compared with (-)-MBP, the enantiomer (+)-MBP was much less active across in vitro affinity and functional assays using mouse and human receptors and also translated in vivo with comparably lower potency and efficacy. Results indicate a 5-HT2C receptor-specific agonist, such as (-)-MBP, may be pharmacotherapeutic for psychoses, without liability for obesity, hallucinations, heart disease, sedation, or motoric disorders.
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Affiliation(s)
- Clinton E Canal
- Center for Drug Discovery (C.E.C., R.G.B.), Department of Pharmaceutical Sciences (C.E.C., R.G.B.), and Department of Chemistry and Chemical Biology (R.G.B.), Northeastern University, Boston, Massachusetts; Department of Psychiatry (D.M.), Medicinal Chemistry (D.F., R.S., K.K., R.G.B.), and Psychology (N.E.R., K.L.R.), University of Florida, Gainesville, Florida
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Tomie A, Lincks M, Nadarajah SD, Pohorecky LA, Yu L. Pairings of lever and food induce Pavlovian conditioned approach of sign-tracking and goal-tracking in C57BL/6 mice. Behav Brain Res 2011; 226:571-8. [PMID: 22026925 DOI: 10.1016/j.bbr.2011.10.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 10/05/2011] [Accepted: 10/14/2011] [Indexed: 11/15/2022]
Abstract
In rats, Pavlovian sign-tracking has been extensively evaluated as a model of compulsiveness in drug addiction and other addictive behaviors, but it remains unexplored in mice, a species with a wealth of genetically modified models, which makes it possible to examine gene-behavior relationships. In C57BL/6 mice, the most commonly used mouse strain for genetic studies, repeated pairings of lever conditioned stimulus (CS) with food unconditioned stimulus (US) induced Pavlovian conditioning of sign-tracking conditioned response (ST CR) performance of lever CS-directed approach, and Pavlovian conditioning of goal-tracking conditioned response (GT CR) performance of approach responses directed at the location of the food trough where the food US was delivered. The CS-US Paired group performed more ST CRs and more GT CRs during sessions 15-16 than did pseudoconditioning controls which received the lever CS and food US randomly with respect to one another. During sessions 15-16, all mice in the Paired group performed more GT CRs than ST CRs, and regression analysis revealed a positive relationship between an individual subject's tendency to perform ST CRs and GT CRs. The mice that performed more ST CRs during sessions 15-16 yielded higher plasma corticosterone levels. These data reveal stable and reliable acquisition and maintenance of ST CR performance and GT CR performance in mice; however, unlike in rats, ST CRs and GT CRs did not vary inversely within subjects. Corticosterone release, a pathophysiological marker of vulnerability to drug abuse, was positively related to ST CR performance.
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Affiliation(s)
- Arthur Tomie
- Center of Alcohol Studies, Rutgers - The State University of New Jersey, 607 Allison Road, Piscataway, NJ 08854-8001, USA
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Murray KC, Stephens MJ, Ballou EW, Heckman CJ, Bennett DJ. Motoneuron excitability and muscle spasms are regulated by 5-HT2B and 5-HT2C receptor activity. J Neurophysiol 2010; 105:731-48. [PMID: 20980537 DOI: 10.1152/jn.00774.2010] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Immediately after spinal cord injury (SCI), a devastating paralysis results from the loss of brain stem and cortical innervation of spinal neurons that control movement, including a loss of serotonergic (5-HT) innervation of motoneurons. Over time, motoneurons recover from denervation and function autonomously, exhibiting large persistent calcium currents (Ca PICs) that both help with functional recovery and contribute to uncontrolled muscle spasms. Here we systematically evaluated which 5-HT receptor subtypes influence PICs and spasms after injury. Spasms were quantified by recording the long-lasting reflexes (LLRs) on ventral roots in response to dorsal root stimulation, in the chronic spinal rat, in vitro. Ca PICs were quantified by intracellular recording in synaptically isolated motoneurons. Application of agonists selective to 5-HT(2B) and 5-HT(2C) receptors (including BW723C86) significantly increased the LLRs and associated Ca PICs, whereas application of agonists to 5-HT(1), 5-HT(2A), 5-HT(3), or 5-HT(4/5/6/7) receptors (e.g., 8-OH-DPAT) did not. The 5-HT(2) receptor agonist-induced increases in LLRs were dose dependent, with doses for 50% effects (EC(50)) highly correlated with published doses for agonist receptor binding (K(i)) at 5-HT(2B) and 5-HT(2C) receptors. Application of selective antagonists to 5-HT(2B) (e.g., RS127445) and 5-HT(2C) (SB242084) receptors inhibited the agonist-induced increase in LLR. However, antagonists that are known to specifically be neutral antagonists at 5-HT(2B/C) receptors (e.g., RS127445) had no effect when given by themselves, indicating that these receptors were not activated by residual 5-HT in the spinal cord. In contrast, inverse agonists (such as SB206553) that block constitutive activity at 5-HT(2B) or 5-HT(2C) receptors markedly reduced the LLRs, indicating the presence of constitutive activity in these receptors. 5-HT(2B) or 5-HT(2C) receptors were confirmed to be on motoneurons by immunolabeling. In summary, 5-HT(2B) and 5-HT(2C) receptors on motoneurons become constitutively active after injury and ultimately contribute to recovery of motoneuron function and emergence of spasms.
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Affiliation(s)
- Katherine C Murray
- Centre for Neuroscience, University of Alberta, Edmonton, Alberta, Canada
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Acquisition session length modulates consolidation effects produced by 5-HT2C ligands in a mouse autoshaping-operant procedure. Behav Pharmacol 2010; 21:83-9. [PMID: 20177374 DOI: 10.1097/fbp.0b013e328337bde7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Although the neurotransmitter, 5-hydroxytryptamine (serotonin, 5-HT), has been implicated as a mediator of learning and memory, the specific role of 5-HT receptors in rodents requires further delineation. In this study, 5-HT2C receptor ligands of varying relative intrinsic efficacies were tested in a mouse learning and memory model called autoshaping-operant. On day 1, mice were placed in experimental chambers and presented with a tone on a variable interval schedule. The tone remained on for 6 s or until a nose-poke response occurred to produce a dipper with Ensure solution. Mice were then injected with saline, MK212 (full agonist), m-chlorophenylpiperazine (partial agonist), mianserin, and SB206 553 (inverse agonists), and methysergide and (+)-2-bromo lysergic acid diethylamide (+)-hydrogen tartrate (neutral antagonists). Each compound was injected after either 1 or 2-h acquisition sessions on day 1 to investigate the role of acquisition session length on consolidation. Day 1 injection of the 5-HT2C inverse agonist mianserin produced greater retrieval impairments of the autoshaped operant response on day 2 than any other agent tested. Furthermore, decreasing the length of the acquisition session to 1h significantly increased the difficulty of the autoshaping task further modulating the consolidation effects produced by the 5-HT2C ligands tested.
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Rondou P, Haegeman G, Van Craenenbroeck K. The dopamine D4 receptor: biochemical and signalling properties. Cell Mol Life Sci 2010; 67:1971-86. [PMID: 20165900 PMCID: PMC11115718 DOI: 10.1007/s00018-010-0293-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 01/19/2010] [Accepted: 01/26/2010] [Indexed: 01/20/2023]
Abstract
Dopamine is an important neurotransmitter that regulates several key functions in the brain, such as motor output, motivation and reward, learning and memory, and endocrine regulation. Dopamine does not mediate fast synaptic transmission, but rather modulates it by triggering slow-acting effects through the activation of dopamine receptors, which belong to the G-protein-coupled receptor superfamily. Besides activating different effectors through G-protein coupling, dopamine receptors also signal through interaction with a variety of proteins, collectively termed dopamine receptor-interacting proteins. We focus on the dopamine D4 receptor, which contains an important polymorphism in its third intracellular loop. This polymorphism has been the subject of numerous studies investigating links with several brain disorders, such as attention-deficit hyperactivity disorder and schizophrenia. We provide an overview of the structure, signalling properties and regulation of dopamine D4 receptors, and briefly discuss their physiological and pathophysiological role in the brain.
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Affiliation(s)
- Pieter Rondou
- Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Ghent University (UGent), K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
- Present Address: Center for Medical Genetics Ghent (CMGG), Ghent University Hospital, Medical Research Building, De Pintelaan 185, 9000 Ghent, Belgium
| | - Guy Haegeman
- Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Ghent University (UGent), K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
| | - Kathleen Van Craenenbroeck
- Laboratory of Eukaryotic Gene Expression and Signal Transduction (LEGEST), Ghent University (UGent), K.L. Ledeganckstraat 35, 9000 Ghent, Belgium
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Vanover KE, Weiner DM, Makhay M, Veinbergs I, Gardell LR, Lameh J, Del Tredici AL, Piu F, Schiffer HH, Ott TR, Burstein ES, Uldam AK, Thygesen MB, Schlienger N, Andersson CM, Son TY, Harvey SC, Powell SB, Geyer MA, Tolf BR, Brann MR, Davis RE. Pharmacological and Behavioral Profile of N-(4-Fluorophenylmethyl)-N-(1-methylpiperidin-4-yl)-N′-(4-(2-methylpropyloxy)phenylmethyl) Carbamide (2R,3R)-Dihydroxybutanedioate (2:1) (ACP-103), a Novel 5-Hydroxytryptamine2A Receptor Inverse Agonist. J Pharmacol Exp Ther 2006; 317:910-8. [PMID: 16469866 DOI: 10.1124/jpet.105.097006] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The in vitro and in vivo pharmacological properties of N-(4-fluorophenylmethyl)-N-(1-methylpiperidin-4-yl)-N'-(4-(2-methylpropyloxy)phenylmethyl)carbamide (2R,3R)-dihydroxybutanedioate (2:1) (ACP-103) are presented. A potent 5-hydroxytryptamine (5-HT)(2A) receptor inverse agonist ACP-103 competitively antagonized the binding of [(3)H]ketanserin to heterologously expressed human 5-HT(2A) receptors with a mean pK(i) of 9.3 in membranes and 9.70 in whole cells. ACP-103 displayed potent inverse agonist activity in the cell-based functional assay receptor selection and amplification technology (R-SAT), with a mean pIC(50) of 8.7. ACP-103 demonstrated lesser affinity (mean pK(i) of 8.80 in membranes and 8.00 in whole cells, as determined by radioligand binding) and potency as an inverse agonist (mean pIC(50) 7.1 in R-SAT) at human 5-HT(2C) receptors, and lacked affinity and functional activity at 5-HT(2B) receptors, dopamine D(2) receptors, and other human monoaminergic receptors. Behaviorally, ACP-103 attenuated head-twitch behavior (3 mg/kg p.o.), and prepulse inhibition deficits (1-10 mg/kg s.c.) induced by the 5-HT(2A) receptor agonist (+/-)-2,5-dimethoxy-4-iodoamphetamine hydrochloride in rats and reduced the hyperactivity induced in mice by the N-methyl-d-aspartate receptor noncompetitive antagonist 5H-dibenzo[a,d]cyclohepten-5,10-imine (dizocilpine maleate; MK-801) (0.1 and 0.3 mg/kg s.c.; 3 mg/kg p.o.), consistent with a 5-HT(2A) receptor mechanism of action in vivo and antipsychotic-like efficacy. ACP-103 demonstrated >42.6% oral bioavailability in rats. Thus, ACP-103 is a potent, efficacious, orally active 5-HT(2A) receptor inverse agonist with a behavioral pharmacological profile consistent with utility as an antipsychotic agent.
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Affiliation(s)
- Kimberly E Vanover
- ACADIA Pharmaceuticals Inc., 3911 Sorrento Valley Blvd., San Diego, CA 92121, USA.
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Prabhakaran J, Parsey RV, Majo VJ, Van Heertum RL, John Mann J, Dileep Kumar JS. Synthesis andin vivo evaluation of [O-methyl-11C] 2-(4-methoxyphenyl)-N-(4-methylbenzyl)-N-(1-methyl- piperidin-4-yl)acetamide as an imaging probe for 5-HT2A receptors. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.1124] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Li Z, Ichikawa J, Huang M, Prus AJ, Dai J, Meltzer HY. ACP-103, a 5-HT2A/2C inverse agonist, potentiates haloperidol-induced dopamine release in rat medial prefrontal cortex and nucleus accumbens. Psychopharmacology (Berl) 2005; 183:144-53. [PMID: 16220333 DOI: 10.1007/s00213-005-0170-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2004] [Accepted: 08/03/2005] [Indexed: 10/25/2022]
Abstract
RATIONALE Atypical antipsychotic drugs (APDs) such as clozapine, olanzapine, quetiapine, risperidone, and ziprasidone are serotonin (5-HT)(2A) antagonists and relatively weaker dopamine (DA) D(2) antagonists, with variable 5-HT(2C) antagonist properties. The ability of atypical APDs to preferentially increase DA release in the cortex compared to the limbic system is believed to be due in part to their antagonism of 5-HT(2A) and D(2) receptors and believed to contribute to their beneficial effects on cognition, negative, and psychotic symptoms. Previous studies from this laboratory using microdialysis have shown that pretreatment of the 5-HT(2A) antagonist M100907 with the typical APD and D(2) antagonist haloperidol produced an increase in the medial prefrontal cortex (mPFC), but not in the nucleus accumbens (NAC), DA release. However, pretreatment with the 5-HT(2A/2C) receptor antagonist SR46349-B with haloperidol increased both mPFC and NAC DA release, suggesting that both 5-HT(2A) and 5-HT(2C) properties may be important for atypical APD effects. OBJECTIVE The purpose of this study was to examine the effects of a novel putative atypical APD ACP-103 on mPFC and NAC DA release using in vivo microdialysis in freely moving rats that are awake. ACP-103 is an inverse agonist at both 5-HT(2A) and 5-HT(2C) receptors and has intermediate affinities for 5-HT(2C) receptors relative to their affinities for 5-HT(2A) receptors compared to M100907 and SR46349-B. In addition, the effects of ACP-103 were compared to M100907 and SR46349-B, and ACP-103 was also coadministered with haloperidol. RESULTS ACP-103 10.0 mg/kg, but not 3.0 mg/kg, increased DA release in the mPFC, while neither dose increased DA release in the NAC. Like M100907, ACP-103 (3.0 mg/kg) potentiated 0.1 mg/kg haloperidol-induced DA release in the mPFC while inhibiting that in the NAC. However, ACP-103 (3.0 mg/kg), similar to SR46349-B, potentiated a high dose of haloperidol (1.0 mg/kg)-induced DA release in both regions. The potent 5-HT(2C) antagonist SB242084 1.0 mg/kg significantly potentiated 0.1 mg/kg haloperidol-induced DA release in both the mPFC and NAC. However, SB242084, at 0.2 mg/kg, significantly potentiated DA release only in the NAC. Moreover, SB242084 0.2 mg/kg potentiated DA release in the NAC produced by the combination treatment of 3 mg/kg ACP-103 and 0.1 mg/kg haloperidol. CONCLUSION These data suggest that the relative extent of 5-HT(2A) and 5-HT(2C) antagonism, as well as the extent of D(2) receptor blockade, has a critical influence on DA release in the mPFC and NAC and may be a determining factor in the action of this class of atypical APDs on these two potentially clinically relevant parameters.
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Affiliation(s)
- Zhu Li
- Psychiatry Department, Psychopharmacology Division, Vanderbilt University School of Medicine, Suite 306, 1601 23rd Ave. S., Nashville, TN 37212, USA.
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