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Scott C, Dodson A, Saulnier M, Snyder K, Racz R. Analysis of secondary pharmacology assays received by the US Food and Drug Administration. J Pharmacol Toxicol Methods 2022; 117:107205. [PMID: 35926773 DOI: 10.1016/j.vascn.2022.107205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 07/09/2022] [Accepted: 07/26/2022] [Indexed: 10/16/2022]
Abstract
Secondary pharmacology studies are a time-efficient and cost-effective method for determining the safety profile of a potential new drug before it enters human trials. The results of these multi-target screens are commonly submitted with Investigational New Drug (IND) applications, but there currently is little guidance on how such information is presented and which targets are chosen for testing. In this study, we expand on our previous analysis of secondary pharmacology reports by manually curating and analyzing all secondary pharmacology results received by the FDA received as part of an IND submission. A total of 1120 INDs submitted by 480 sponsors between 1999 and October 2020 were included in this study. The overall results were largely consistent with previous internal and external studies, showing that the most tested target in our set was the histamine 1 receptor (tested 938 times), the most hit target was sodium channel site 2 (hit 141 times), and the target with the highest hit percentage was the vesicular monoamine transporter 2 (hit 42.2% of the time). Additionally, this study demonstrated that improvements in the secondary pharmacology submission process, such as changes in formatting and nomenclature, could enhance the utility of these assays for regulatory review, including assisting with identifying the safety liabilities of a drug candidate early in development. This updated data set will allow FDA-industry collaborative working groups to continue developing the best methods for regulatory submission of secondary pharmacology data and evaluate the need for a standard target panel.
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Affiliation(s)
- Christina Scott
- Division of Applied Regulatory Science, Food and Drug Administration, Silver Spring, MD 20993, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, USA
| | - Andrew Dodson
- Division of Applied Regulatory Science, Food and Drug Administration, Silver Spring, MD 20993, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, USA
| | - Muriel Saulnier
- Office of New Drugs, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Kevin Snyder
- Office of New Drugs, Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Rebecca Racz
- Division of Applied Regulatory Science, Food and Drug Administration, Silver Spring, MD 20993, USA.
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Iwamura Y, Nakayama T, Matsumoto A, Ogi Y, Yamaguchi M, Kobayashi A, Matsumoto K, Katsura Y, Konoike N, Nakamura K, Ikeda K. Effect of dopamine receptor-related compounds on naive common marmosets for auditory steady state response. J Neurophysiol 2022; 128:229-238. [PMID: 35583977 DOI: 10.1152/jn.00147.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Abnormalities of auditory steady state responses (ASSR) and the effects of antipsychotic drugs on ASSR have been investigated in patients with schizophrenia. It is presumed that effects of drugs do not directly reflect on ASSR, because of ASSR abnormalities associated with schizophrenia. Therefore, to investigate the direct effect of drugs on ASSR, we established an ASSR evaluation system for common marmosets in a naïve state. Dopamine D1 receptor stimulation (SKF-81297, 2 mg/kg, intraperitoneal) significantly increased evoked power (EP) at 40 Hz. The phase locking factor (PLF) was increased significantly at 20, 30, 40, and 80 Hz. However, the administration of a dopamine D1 receptor antagonist (SCH-39166, 0.3 mg/kg intraperitoneal) resulted in a significant decrease in EP and PLF at 30 Hz. Dopamine D2 receptor stimulation (quinpirole, 1 mg/kg, intramuscular) tended to increase EP and induced power (IP) at all frequencies, and a significant difference was observed at 30 Hz IP. There was no change in PLF at all frequencies. In addition, dopamine D2 receptor blockade (raclopride, 3 mg/kg, intraperitoneal) reduced EP and PLF at 30 Hz. Subcutaneous administration of the serotonin dopamine antagonist, risperidone (0.3 mg/kg), tended to increase IP and decrease PLF, but not significantly. Taken together, it is possible to compare the differences in the mode of action of drugs on ASSR using naïve non-human primates.
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Affiliation(s)
- Yoshihiro Iwamura
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Tatsuo Nakayama
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Atsushi Matsumoto
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Yuji Ogi
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Masataka Yamaguchi
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Atsushi Kobayashi
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Kenji Matsumoto
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Yasunori Katsura
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
| | - Naho Konoike
- Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Aichi, Japan
| | - Katsuki Nakamura
- Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Aichi, Japan
| | - Kazuhito Ikeda
- Platform Technology Research Unit, Drug Research Division, Sumitomo Pharma, Co., Osaka, Japan
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Dodson A, Mi K, Russo DP, Scott C, Saulnier M, Snyder K, Racz R. Aggregation and analysis of secondary pharmacology data from investigational new drug submissions at the US Food and Drug Administration. J Pharmacol Toxicol Methods 2021; 111:107098. [PMID: 34229067 DOI: 10.1016/j.vascn.2021.107098] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/14/2021] [Accepted: 06/29/2021] [Indexed: 01/23/2023]
Abstract
Secondary pharmacology studies are utilized by the pharmaceutical industry as a cost-efficient tool to identify potential safety liabilities of drugs before entering Phase 1 clinical trials. These studies are recommended by the Food and Drug Administration (FDA) as a part of the Investigational New Drug (IND) application. However, despite the utility of these assays, there is little guidance on which targets should be screened and which format should be used. Here, we evaluated 226 secondary pharmacology profiles obtained from close to 90 unique sponsors. The results indicated that the most tested target in our set was the GABA benzodiazepine receptor (tested 168 times), the most hit target was adenosine 3 (hit 24 times), and the target with the highest hit percentage was the quinone reductase 2 (NQO2) receptor (hit 29% of the time). The overall results were largely consistent with those observed in previous publications. However, this study also identified the need for improvement in the submission process of secondary pharmacology studies by industry, which could enhance their utility for regulatory purpose. FDA-industry collaborative working groups will utilize this data to determine the best methods for regulatory submission of these studies and evaluate the need for a standard target panel.
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Affiliation(s)
- Andrew Dodson
- Division of Applied Regulatory Science, Food and Drug Administration, Silver Spring, MD 20993, United States of America; Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, United States of America
| | - Kevin Mi
- Office of New Drugs, Food and Drug Administration, Silver Spring, MD 20993, United States of America
| | - Daniel P Russo
- Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, United States of America; Office of New Drugs, Food and Drug Administration, Silver Spring, MD 20993, United States of America
| | - Christina Scott
- Division of Applied Regulatory Science, Food and Drug Administration, Silver Spring, MD 20993, United States of America; Oak Ridge Institute for Science and Education, Oak Ridge, TN 37830, United States of America
| | - Muriel Saulnier
- Office of New Drugs, Food and Drug Administration, Silver Spring, MD 20993, United States of America
| | - Kevin Snyder
- Office of New Drugs, Food and Drug Administration, Silver Spring, MD 20993, United States of America
| | - Rebecca Racz
- Division of Applied Regulatory Science, Food and Drug Administration, Silver Spring, MD 20993, United States of America.
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Liu PP, Chao CC, Liao RM. Task-Dependent Effects of SKF83959 on Operant Behaviors Associated With Distinct Changes of CaMKII Signaling in Striatal Subareas. Int J Neuropsychopharmacol 2021; 24:721-733. [PMID: 34049400 PMCID: PMC8453300 DOI: 10.1093/ijnp/pyab032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 04/21/2021] [Accepted: 05/27/2021] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND SKF83959, an atypical dopamine (DA) D1 receptor agonist, has been used to test the functions of DA-related receptor complexes in vitro, but little is known about its impact on conditioned behavior. The present study examined the effects of SKF83959 on operant behaviors and assayed the neurochemical mechanisms involved. METHODS Male rats were trained and maintained on either a fixed-interval 30-second (FI30) schedule or a differential reinforcement of low-rate response 10-second (DRL10) schedule of reinforcement. After drug treatment tests, western blotting assayed the protein expressions of the calcium-/calmodulin-dependent protein kinase II (CaMKII) and the transcription factor cyclic AMP response element binding protein (CREB) in tissues collected from 4 selected DA-related areas. RESULTS SKF83959 disrupted the performance of FI30 and DRL10 behaviors in a dose-dependent manner by reducing the total number of responses in varying magnitudes. Moreover, the distinct profiles of the behavior altered by the drug were manifested by analyzing qualitative and quantitative measures on both tasks. Western-blot results showed that phospho-CaMKII levels decreased in the nucleus accumbens and the dorsal striatum of the drug-treated FI30 and DRL10 subjects, respectively, compared with their vehicle controls. The phospho-CREB levels decreased in the nucleus accumbens and the hippocampus of drug-treated FI30 subjects but increased in the nucleus accumbens of drug-treated DRL10 subjects. CONCLUSIONS Our results provide important insight into the neuropsychopharmacology of SKF83959, indicating that the drug-altered operant behavior is task dependent and related to regional-dependent changes of CaMKII-CREB signaling in the mesocorticolimbic DA systems.
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Affiliation(s)
- Pei-Pei Liu
- Department of Psychology, National Cheng-Chi University, Taipei, Taiwan,National Cheng-Chi University, Taipei, Taiwan
| | - Chih-Chang Chao
- Institute of Neuroscience and Research Center for Mind, Brain and Learning, National Cheng-Chi University, Taipei, Taiwan,National Cheng-Chi University, Taipei, Taiwan,Correspondence: Chih-Chang Chao, PhD, Institute of Neuroscience ()
| | - Ruey-Ming Liao
- Department of Psychology, National Cheng-Chi University, Taipei, Taiwan,Institute of Neuroscience and Research Center for Mind, Brain and Learning, National Cheng-Chi University, Taipei, Taiwan,National Cheng-Chi University, Taipei, Taiwan,Correspondence: Ruey-Ming Liao, PhD, Department of Psychology, National Cheng-Chi University, 64, Sec. 2, Zhinan Road, Taipei City 116011, Taiwan ()
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Remez N, Garcia-Serna R, Vidal D, Mestres J. The In Vitro Pharmacological Profile of Drugs as a Proxy Indicator of Potential In Vivo Organ Toxicities. Chem Res Toxicol 2016; 29:637-48. [PMID: 26952164 DOI: 10.1021/acs.chemrestox.5b00470] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The potential of a drug to cause certain organ toxicities is somehow implicitly contained in its full pharmacological profile, provided the drug reaches and accumulates at the various organs where the different interacting proteins in its profile, both targets and off-targets, are expressed. Under this assumption, a computational approach was implemented to obtain a projected anatomical profile of a drug from its in vitro pharmacological profile linked to protein expression data across 47 organs. It was observed that the anatomical profiles obtained when using only the known primary targets of the drugs reflected roughly the intended organ targets. However, when both known and predicted secondary pharmacology was considered, the projected anatomical profiles of the drugs were able to clearly highlight potential organ off-targets. Accordingly, when applied to sets of drugs known to cause cardiotoxicity and hepatotoxicity, the approach is able to identify heart and liver, respectively, as the organs where the proteins in the pharmacological profile of the corresponding drugs are specifically expressed. When applied to a set of drugs linked to a risk of Torsades de Pointes, heart is again the organ clearly standing out from the rest and a potential protein profile hazard is proposed. The approach can be used as a proxy indicator of potential in vivo organ toxicities.
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Affiliation(s)
- Nikita Remez
- Systems Pharmacology, Research Program on Biomedical Informatics (GRIB), IMIM Hospital del Mar Medical Research Institute and University Pompeu Fabra, Parc de Recerca Biomèdica , Doctor Aiguader 88, 08003 Barcelona, Catalonia, Spain.,Chemotargets SL, Parc Científic de Barcelona, Baldiri Reixac 4 (TI-05A7), 08028 Barcelona, Catalonia, Spain
| | - Ricard Garcia-Serna
- Chemotargets SL, Parc Científic de Barcelona, Baldiri Reixac 4 (TI-05A7), 08028 Barcelona, Catalonia, Spain
| | - David Vidal
- Chemotargets SL, Parc Científic de Barcelona, Baldiri Reixac 4 (TI-05A7), 08028 Barcelona, Catalonia, Spain
| | - Jordi Mestres
- Systems Pharmacology, Research Program on Biomedical Informatics (GRIB), IMIM Hospital del Mar Medical Research Institute and University Pompeu Fabra, Parc de Recerca Biomèdica , Doctor Aiguader 88, 08003 Barcelona, Catalonia, Spain.,Chemotargets SL, Parc Científic de Barcelona, Baldiri Reixac 4 (TI-05A7), 08028 Barcelona, Catalonia, Spain
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Rodent models of impulsive–compulsive behaviors in Parkinson's disease: How far have we reached? Neurobiol Dis 2015; 82:561-573. [DOI: 10.1016/j.nbd.2015.08.026] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/22/2015] [Accepted: 08/25/2015] [Indexed: 01/26/2023] Open
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Conroy JL, Free RB, Sibley DR. Identification of G protein-biased agonists that fail to recruit β-arrestin or promote internalization of the D1 dopamine receptor. ACS Chem Neurosci 2015; 6:681-92. [PMID: 25660762 DOI: 10.1021/acschemneuro.5b00020] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The D1 dopamine receptor (D1R) has been implicated in numerous neuropsychiatric disorders, and D1R-selective ligands have potential as therapeutic agents. Previous studies have identified substituted benzazepines as D1R-selective agonists, but the in vivo effects of these compounds have not correlated well with their in vitro pharmacological activities. A series of substituted benzazepines, and structurally dissimilar D1R-selective agonists, were tested for their functional effects on D1R-mediated cAMP accumulation, D1R-promoted β-arrestin recruitment, and D1R internalization using live cell functional assays. All compounds tested elicited an increase in the level of cAMP accumulation, albeit with a range of efficacies. However, when the compounds were evaluated for β-arrestin recruitment, a subset of substituted benzazepines, SKF83959, SKF38393, SKF82957, SKF77434, and SKF75670, failed to activate this pathway, whereas the others showed similar activation efficacies as seen with cAMP accumulation. When tested as antagonists, the five biased compounds all inhibited dopamine-stimulated β-arrestin recruitment. Further, D1R internalization assays revealed a corroborating pattern of activity in that the G protein-biased compounds failed to promote D1R internalization. Interestingly, the biased signaling was unique for the D1R, as the same compounds were agonists of the related D5 dopamine receptor (D5R), but revealed no signaling bias. We have identified a group of substituted benzazepine ligands that are agonists at D1R-mediated G protein signaling, but antagonists of D1R recruitment of β-arrestin, and also devoid of agonist-induced receptor endocytosis. These data may be useful for interpreting the contrasting effects of these compounds in vitro versus in vivo, and also for the understanding of pathway-selective signaling of the D1R.
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Affiliation(s)
- Jennie L. Conroy
- Molecular Neuropharmacology Section,
National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-9405, United States
| | - R. Benjamin Free
- Molecular Neuropharmacology Section,
National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-9405, United States
| | - David R. Sibley
- Molecular Neuropharmacology Section,
National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892-9405, United States
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Reducing safety-related drug attrition: the use of in vitro pharmacological profiling. Nat Rev Drug Discov 2012. [DOI: 10.1038/nrd3845] [Citation(s) in RCA: 470] [Impact Index Per Article: 39.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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9
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Frederick AL, Saborido TP, Stanwood GD. Neurobehavioral phenotyping of G(αq) knockout mice reveals impairments in motor functions and spatial working memory without changes in anxiety or behavioral despair. Front Behav Neurosci 2012; 6:29. [PMID: 22723772 PMCID: PMC3377978 DOI: 10.3389/fnbeh.2012.00029] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 05/29/2012] [Indexed: 11/18/2022] Open
Abstract
Many neurotransmitters, hormones, and sensory stimuli elicit their cellular responses through the targeted activation of receptors coupled to the Gαq family of heterotrimeric G proteins. Nevertheless, we still understand little about the consequences of loss of this signaling activity on brain function. We therefore examined the effects of genetic inactivation of Gnaq, the gene that encode for Gαq, on responsiveness in a battery of behavioral tests in order to assess the contribution of Gαq signaling capacity in the brain circuits mediating expression of affective behaviors (anxiety and behavioral despair), spatial working memory, and locomotor output (coordination, strength, spontaneous activity, and drug-induced responses). First, we replicated and extended findings showing clear motor deficits in Gαq knockout mice as assessed on an accelerating rotarod and the inverted screen test. We then assessed the contribution of the basal ganglia motor loops to these impairments, using open field testing and analysis of drug-induced locomotor responses to the psychostimulant cocaine, the benzazepine D1 receptor agonists SKF83822 and SKF83959, and the NMDA receptor antagonist MK-801. We observed significant increases in drug-induced locomotor activity in Gαq knockout mice from the dopaminergic agonists but not MK-801, indicating that basal ganglia locomotor circuitry is largely intact in the absence of Gαq. Additionally, we observed normal phenotypes in both the elevated zero maze and the forced swim test indicating that anxiety and depression-related circuitry appears to be largely intact after loss of Gnaq expression. Lastly, use of the Y-maze revealed spatial memory deficits in Gαq knockout mice, indicating that receptors signaling through Gαq are necessary in these circuits for proficiency in this task.
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Affiliation(s)
- Aliya L Frederick
- Neuroscience Graduate Program, Vanderbilt University School of Medicine, Nashville TN, USA
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Zhang J, Xiong B, Zhen X, Zhang A. Dopamine D1receptor ligands: Where are we now and where are we going. Med Res Rev 2009; 29:272-94. [DOI: 10.1002/med.20130] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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11
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O'Sullivan GJ, Dunleavy M, Hakansson K, Clementi M, Kinsella A, Croke DT, Drago J, Fienberg AA, Greengard P, Sibley DR, Fisone G, Henshall DC, Waddington JL. Dopamine D1 vs D5 receptor-dependent induction of seizures in relation to DARPP-32, ERK1/2 and GluR1-AMPA signalling. Neuropharmacology 2008; 54:1051-61. [PMID: 18367215 DOI: 10.1016/j.neuropharm.2008.02.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Revised: 02/10/2008] [Accepted: 02/13/2008] [Indexed: 10/22/2022]
Abstract
Recent reports have shown that the selective dopamine D(1)-like agonist SKF 83822 [which stimulates adenylate cyclase, but not phospholipase C] induces prominent behavioral seizures in mice, whereas its benzazepine congener SKF 83959 [which stimulates phospholipase C, but not adenylate cyclase] does not. To investigate the relative involvement of D(1) vs D(5) receptors in mediating seizures, ethological behavioral topography and cortical EEGs were recorded in D(1), D(5) and DARPP-32 knockout mice in response to a convulsant dose of SKF 83822. SKF 83822-induced behavioral and EEG seizures were gene dose-dependently abolished in D(1) knockouts. In both heterozygous and homozygous D(5) knockouts, the latency to first seizure was significantly increased and total EEG seizures were reduced relative to wild-types. The majority (60%) of homozygous DARPP-32 knockouts did not have seizures; of those having seizures (40%), the latency to first seizure was significantly increased and the number of high amplitude, high frequency polyspike EEG events was reduced. In addition, immunoblotting was performed to investigate downstream intracellular signalling mechanisms at D(1)-like receptors following challenge with SKF 83822 and SKF 83959. In wild-types administered SKF 83822, levels of ERK1/2 and GluR1 AMPA receptor phosphorylation increased two-fold in both the striatum and hippocampus; in striatal slices DARPP-32 phosphorylation at Thr34 increased five-fold relative to vehicle-treated controls. These findings indicate that D(1), and to a lesser extent D(5), receptor coupling to DARPP-32, ERK1/2 and glutamatergic signalling is involved in mediating the convulsant effects of SKF 83822.
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Affiliation(s)
- Gerard J O'Sullivan
- Molecular & Cellular Therapeutics and RCSI Research Institute, Royal College of Surgeons in Ireland, Dublin 2, Ireland
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Desai RI, Neumeyer JL, Bergman J, Paronis CA. Pharmacological characterization of the effects of dopamine D(1) agonists on eye blinking in rats. Behav Pharmacol 2008; 18:745-54. [PMID: 17989512 DOI: 10.1097/fbp.0b013e3282f14ee6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Dopamine D(1)-like partial agonists antagonize some abuse-related effects of cocaine and have been proposed as candidate medications for psychostimulant abuse. Earlier studies have showed that D(1)-like agonists increase eye blinking in monkeys and that the magnitude of this effect may be related to agonist efficacy. These studies characterized the effects of D(1)-like agonists on eye blinking in female Sprague-Dawley rats placed in customized restraint tubes. After vehicle injections, eye blink rates averaged 2.1+/-0.25 blinks/min, or 31+/-4 blinks/15 min. The D(1)-like agonists SKF 82958 and R(+)-6Br-APB dose-dependently increased eye blinking to 136 and 124/15 min, respectively. The selective D(1)-like antagonist SCH 23390 decreased eye blinking and the peripherally selective D(1)-like agonist fenoldopam, the D(2)-like agonist (+)PHNO, and the indirect dopamine agonist methamphetamine all failed to alter eye blink rates relative to vehicle levels. Additional studies with unique congeners and isomers of the D(1)-like partial agonist SKF 83959, MCL 202, MCL 204, MCL 206, MCL 207 and MCL 209, resulted in only moderate increases in eye blink rates (27-84 blinks/15 min). These effects were dose-related for one compound, MCL 209 (max 84+/-19 blinks/15 min) and plateaued at the highest doses, suggestive of partial agonist effects. Additionally, the agonist MCL 206, like the D(1)antagonist SCH 23390, antagonized the effects of SKF 82958 on eye blinking. The findings suggest that D(1)-like agonists increase eye blinking in rats and that these effects may provide a simple measure that can be used to distinguish partial D(1)-like ligands. Further studies with novel D(1)-like partial agonists may be useful in the development of pharmacotherapies for cocaine abuse.
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Affiliation(s)
- Rajeev I Desai
- Preclinical Pharmacology Laboratory, McLean Hospital/Harvard Medical School, Belmont, Massachusetts 02478, USA
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Wirtshafter D. Rotation and immediate-early gene expression in rats treated with the atypical D1 dopamine agonist SKF 83822. Pharmacol Biochem Behav 2007; 86:505-10. [PMID: 17306871 PMCID: PMC1913484 DOI: 10.1016/j.pbb.2007.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Revised: 01/05/2007] [Accepted: 01/12/2007] [Indexed: 11/15/2022]
Abstract
Classical agonists of the dopamine D1 receptor activate both adenylyl cyclase and phospholipase C (PLC) signaling pathways. As a result, the extent to which these two pathways are essentially involved in various effects produced by D1 receptor agonists is currently uncertain. In the present report we examined the effects of SKF 83822, a dopamine D1 agonist which has been reported to activate adenylyl cyclase, but not PLC, on behavior and immediate early gene (IEG) expression in rats with unilateral 6-hydroxydopamine lesions. SKF 83822 (25-100 microg/kg) induced dose dependent contralateral rotation in these subjects, and, additionally, stimulated strong expression of the IEG products c-Fos, Fra2, Zif/268 and Arc in the deinnervated striatum. All of these effects could be antagonized by pretreatment with the selective D1 dopamine antagonist SCH 23390 (0.5 mg/kg). Although PLC may be involved in many effects mediated through dopamine D1 receptors, these results suggest that direct activation of PLC is not necessary for the induction of either rotation or IEG expression in dopamine depleted rats.
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Affiliation(s)
- David Wirtshafter
- Laboratory of Integrative Neuroscience, Department of Psychology, M/C 285, University of Illinois at Chicago, Chicago, IL 60607-7137, USA.
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Desai RI, Neumeyer JL, Paronis CA, Nguyen P, Bergman J. Behavioral effects of the R-(+)- and S-(-)-enantiomers of the dopamine D(1)-like partial receptor agonist SKF 83959 in monkeys. Eur J Pharmacol 2006; 558:98-106. [PMID: 17207791 PMCID: PMC2447824 DOI: 10.1016/j.ejphar.2006.11.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2006] [Revised: 11/16/2006] [Accepted: 11/21/2006] [Indexed: 11/18/2022]
Abstract
Dopamine D(1)-like partial receptor agonists such as SKF 83959 have been proposed as potential candidates for the treatment of cocaine addiction. The present studies were conducted to further characterize SKF 83959 by pharmacologically evaluating effects of its R-(+)- and S-(-)-enantiomers, MCL 202 and MCL 201, respectively, on overt behavior (eye blinking) and schedule-controlled performance in squirrel monkeys. MCL 202, like the D(1) full receptor agonist SKF 82958, produced dose-related increases in eye blinking and decreases in rates of fixed-ratio responding. However, the magnitude of effects of MCL 202 on eye blinking was less than observed with SKF 82958. In contrast to the effects of its R-(+) enantiomer, MCL 201 was relatively devoid of behavioral activity up to doses that were approximately 10-fold greater than MCL 202. Pretreatment with the selective D(1)-like receptor antagonist SCH 39166 dose-dependently antagonized increases in eye blinking produced by MCL 202, confirming the involvement of D(1) mechanisms in its effects. A dose-ratio analysis of the antagonism of effects of MCL 202 by SCH 39166 revealed an apparent pA(2) value of 7.675 with a slope of -0.78+/-0.04. In further studies, pretreatment with MCL 202 antagonized the effects of SKF 82958 on eye blinking and, like SCH 39166, schedule-controlled behavior in a dose-related manner. A dose-ratio analysis of the antagonist effects of MCL 202 on the SKF 82958-induced increases in eye blinking revealed ratios of 2.7, 4.8 and 31.1 for 0.1, 0.3 and 1.0 mg/kg dose of the antagonist, respectively, indicative of a significant change in the potency of SKF 82958. These results suggest that MCL 202, like its parent compound SKF 83959, has both D(1) receptor-mediated agonist and antagonist properties, consistent with its characterization as a partial agonist at the D(1)-like receptor. In addition, the inactivity of MCL 201, the S-(-)-enantiomer, suggests that the behavioral effects of SKF 83959 can be attributed primarily to the activity of its R-(+)-enantiomer.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/analogs & derivatives
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- Animals
- Behavior, Animal/drug effects
- Benzazepines/pharmacology
- Blinking/drug effects
- Conditioning, Psychological/drug effects
- Dopamine Agonists/pharmacology
- Male
- Receptors, Dopamine D1/agonists
- Saimiri
- Stereoisomerism
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Affiliation(s)
- Rajeev I. Desai
- McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
| | - John L. Neumeyer
- McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
- Brain Research Laboratories, Inc., 115 Mill Street, Belmont, MA 02478, USA
| | - Carol A. Paronis
- McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
- Brain Research Laboratories, Inc., 115 Mill Street, Belmont, MA 02478, USA
| | - Phong Nguyen
- McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
| | - Jack Bergman
- McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
- Brain Research Laboratories, Inc., 115 Mill Street, Belmont, MA 02478, USA
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15
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Fujita S, Lee J, Kiguchi M, Uchida T, Cools AR, Waddington JL, Koshikawa N. Topographical resolution of jaw movements mediated by cyclase- vs. non-cyclase-coupled dopamine D1-like receptors: Studies with SK&F 83822. Eur J Pharmacol 2006; 538:94-100. [PMID: 16682023 DOI: 10.1016/j.ejphar.2006.03.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 03/17/2006] [Accepted: 03/27/2006] [Indexed: 11/29/2022]
Abstract
This study examined the effects on orofacial movement topography of SK&F 83822 ([R/S]-6-chloro-7,8-dihydroxy-3-allyl-1-[3-methylphenyl]-2,3,4,5-tetrahydro-1H-3-benzazepine), which stimulates dopamine D(1)-like receptors coupled to stimulation of adenylyl cyclase (AC) but not phosphoinositide (PI) hydrolysis, in comparison with SK&F 83959 ([R/S]-3-methyl-6-chloro-7,8-dihydroxy-1-[3-methyl-phenyl]-2,3,4,5-tetrahydro-1H-3-benzazepine), which stimulates PI hydrolysis but not AC. SK&F 83822 alone induced chattering, while SK&F 83959 alone exerted little effect. SK&F 83822 and SK&F 83959 each in combination with the dopamine D(2)-like agonist quinpirole resulted in synergistic induction of non-chattering movements with tongue protrusions. These effects were blocked by the dopamine D(1)-like receptor antagonist SCH 23390 ([R]-3-methyl-7-chloro-8-hydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine). However, the dopamine D(2)-like receptor antagonist YM 09151-2 (cis-N-[1-benzyl-2-methyl-pyrrolidin-3-yl]-5-chloro-2-methoxy-4-methylaminobenzamide) exerted a biphasic effect on synergism with SK&F 83822: chattering was initially released but antagonised thereafter. Only antagonism was seen for synergism with SK&F 83959. While both AC- and PI-coupled dopamine D(1)-like receptors participate in synergistic dopamine D(1)-like:D(2)-like receptor interactions, topographically specific synergistic and oppositional dopamine D(1)-like:D(2)-like interactions evident with SK&F 83822 reflect the involvement primarily of D(1)-like receptors coupled to AC rather than PI.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/analogs & derivatives
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- Adenylyl Cyclases/metabolism
- Analysis of Variance
- Animals
- Benzamides/pharmacology
- Benzazepines/pharmacology
- Dopamine Agonists/pharmacology
- Dopamine Antagonists/pharmacology
- Jaw/physiology
- Male
- Movement/drug effects
- Quinpirole/pharmacology
- Rats
- Rats, Sprague-Dawley
- Receptors, Dopamine D1/agonists
- Receptors, Dopamine D1/antagonists & inhibitors
- Receptors, Dopamine D1/physiology
- Time Factors
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Affiliation(s)
- Satoshi Fujita
- Department of Pharmacology, Nihon University School of Dentistry, 1-8-13, Kanda-Surugadai, Chiyoda-ku, Tokyo 101-8310, Japan
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16
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O'Sullivan GJ, Kinsella A, Grandy DK, Tighe O, Croke DT, Waddington JL. Ethological resolution of behavioral topography and D2-like vs. D1-like agonist responses in congenic D4 dopamine receptor "knockouts": identification of D4:D1-like interactions. Synapse 2006; 59:107-18. [PMID: 16320306 DOI: 10.1002/syn.20225] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
To clarify the involvement of dopamine D4 receptors in behavioral regulation, the phenotypic ethogram of congenic D4 "knockout" mice was studied in terms of (i) course of exploration and habituation, and (ii) topographical responsiveness to the selective D2-like agonist RU 24213 and the selective D1-like agonists A 68930, SK&F 83959 and SK&F 83822. Congenic D4 knockouts were characterized by a small reduction in exploratory sniffing with delayed habituation of sifting. The magnitude and topographical specificity of these effects indicated that any functional role for D4 receptors in exploratory processes is subtle. Induction of stereotyped, ponderous locomotion by RU 24213 was reduced in D4-null mice consistent with an involvement of D4 receptors in the topographical expression of stereotypy. Induction of grooming and, at higher doses, seizures by A 68930, which stimulates both adenylyl cyclase (AC) and phospholipase C (PLC), were unaltered in congenic D4 knockouts. In contrast, induction of grooming by SK&F 83959, which stimulates PLC but not AC and fails to induce seizures, was reduced in D4-null mice; this indicates that D4 receptors interact with PLC-coupled D1-like receptors in regulating D1-like-mediated grooming. Conversely, induction of seizures by SK&F 83822, which stimulates AC but not PLC and fails to induce grooming, was reduced in congenic D4 knockouts; this indicates that D4 receptors interact with AC-coupled D1-like receptors in regulating D1-like-mediated seizures. These studies identify novel functional roles for the D4 receptor that are distinct from those of closely related D2-like family members and involve interactions with their D1-like counterparts.
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Affiliation(s)
- Gerard J O'Sullivan
- Department of Clinical Pharmacology and Research Institute, Royal College of Surgeons in Ireland, Dublin 2, Ireland
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17
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Asencio M, Hurtado-Guzmán C, López JJ, Cassels BK, Protais P, Chagraoui A. Structure-affinity relationships of halogenated predicentrine and glaucine derivatives at D1 and D2 dopaminergic receptors: halogenation and D1 receptor selectivity. Bioorg Med Chem 2005; 13:3699-704. [PMID: 15862999 DOI: 10.1016/j.bmc.2005.03.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2005] [Revised: 03/11/2005] [Accepted: 03/11/2005] [Indexed: 11/19/2022]
Abstract
Halogenation of the aporphine alkaloid boldine at the 3-position leads to increased affinity for rat brain D(1)-like dopaminergic receptors with some selectivity over D(2)-like receptors. A series of 3-halogenated and 3,8-dihalogenated (halogen=Cl, Br or I) derivatives of predicentrine (9-O-methylboldine) and glaucine (2,9-di-O-methylboldine) were prepared and assayed for binding at D(1) and D(2) sites. Halogenation of predicentrine led to strong increases in affinity for D(1)-like receptors, while the affinities for D(2)-like receptors were either practically unchanged or reduced three- to fourfold. Halogenated glaucine derivatives did not show any clear trend towards enhanced selectivity, and the affinities were poor and similar to or worse than the values previously recorded for glaucine itself. Together with earlier work on boldine derivatives, these results suggest that the 2-hydroxy group on the aporphine skeleton may determine a binding mode favoring D(1)-like over D(2)-like receptors, with enhanced affinity when the C-3 position is halogenated.
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Affiliation(s)
- Marcelo Asencio
- Department of Chemistry and Millennium Institute for Advanced Studies in Cell Biology and Biotechnology (CBB), Faculty of Sciences, University of Chile, Casilla 653, Santiago, Chile
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18
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Zhang ZJ, Jiang XL, Zhang SE, Hough CJ, Li H, Chen JG, Zhen XC. The paradoxical effects of SKF83959, a novel dopamine D1-like receptor agonist, in the rat acoustic startle reflex paradigm. Neurosci Lett 2005; 382:134-8. [PMID: 15911136 DOI: 10.1016/j.neulet.2005.03.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Revised: 02/21/2005] [Accepted: 03/02/2005] [Indexed: 11/21/2022]
Abstract
While the benzazepine SKF83959 elicits classical behavioral responses associated with dopamine D1 receptors, it also acts as a D1 receptor antagonist biochemically. The paradoxical properties of this agent remain an enigma. In the present study, we sought to determine the behavioral effects of SKF83959 in the rat acoustic startle reflex test. Systemic administration of SKF83959 produced a dose-related increase in the startle amplitude with a stimulus of 105 dB, and a significant group difference was observed between animals treated with 1 mg/kg SKF83959 and vehicle controls. SKF83959 also significantly reduced the latency to startle response to stimuli of 95 dB and 105 dB in a dose-dependent manner. However, unlike classical dopamine D1-like receptor agonists, SKF83959 failed to disrupt prepulse inhibition (PPI) of either the startle amplitude or the latency to startle response; rather, the agent dose-dependently increased the PPI latency to startle response of 105 dB stimulus. These results suggest that the behavioral effects of SKF83959 in the rat acoustic startle reflex paradigm are paradoxical, and these paradoxical effects may be associated with its distinct pharmacological properties.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/analogs & derivatives
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- Acoustic Stimulation
- Animals
- Dopamine Agonists/pharmacology
- Dose-Response Relationship, Drug
- Male
- Rats
- Rats, Sprague-Dawley
- Receptors, Dopamine D1/agonists
- Reflex, Startle/drug effects
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Affiliation(s)
- Zhang-Jin Zhang
- Department of Psychiatry, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
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19
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O'Sullivan GJ, Roth BL, Kinsella A, Waddington JL. SK&F 83822 distinguishes adenylyl cyclase from phospholipase C-coupled dopamine D1-like receptors: behavioural topography. Eur J Pharmacol 2005; 486:273-80. [PMID: 14985049 DOI: 10.1016/j.ejphar.2004.01.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2003] [Revised: 01/05/2004] [Accepted: 01/08/2004] [Indexed: 11/24/2022]
Abstract
Effects of SK&F 83822 [3-allyl-6-chloro-7,8-dihydroxy-1-(3-methylphenyl)-2,3,4,5-tetrahydro-1H-3-benzazepine], an agonist at dopamine D1-like receptors which stimulate adenylyl cyclase but not phosphoinositide hydrolysis, were studied topographically so as to clarify differences between these receptors in the regulation of behaviour. Using cloned receptors, SK&F 83822 showed high, selective affinity for dopamine D1 and D5 over D2, D3, D4 and several non-dopamine receptors. SK&F 83822 induced little intense grooming, but readily induced sniffing, locomotion and rearing; seizures were evident at higher doses, characterised by tonic convulsions, forepaw myoclonus and explosive hyperlocomotion. The dopamine D1-like receptor antagonist SCH 23390 [R(+)-3-methyl-7-chloro-8-hydroxy-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine] readily antagonised these responses to SK&F 83822, particularly seizure activity. The dopamine D2-like receptor antagonist YM 09151-2 [cis-N-(1-benzyl-2-methyl-pyrrolidin-3-yl)-5-chloro-2-methoxy-4-methylaminobenzamide] did not alleviate seizures induced by SK&F 83822; YM 09151-02 did, however, attenuate SK&F 83822-induced sniffing, locomotion and rearing, and released vacuous chewing. These findings indicate that dopamine D1-like receptors linked to adenylyl cyclase can be differentiated from those not linked to adenylyl cyclase in terms of their roles in the topographical regulation of behaviour. For example, the seizure and vacuous chewing responses appear to involve dopamine D1-like receptors that stimulate adenylyl cyclase, while intense grooming involves those which do not.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/analogs & derivatives
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- Adenylyl Cyclases/metabolism
- Animals
- Benzamides/pharmacology
- Benzazepines/pharmacology
- Binding, Competitive
- Dopamine D2 Receptor Antagonists
- Male
- Mice
- Mice, Inbred C57BL
- Motor Activity/drug effects
- Radioligand Assay
- Receptors, Dopamine D1/agonists
- Receptors, Dopamine D1/antagonists & inhibitors
- Receptors, Dopamine D1/metabolism
- Type C Phospholipases/metabolism
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Affiliation(s)
- Gerard J O'Sullivan
- Department of Clinical Pharmacology and Institute of Biopharmaceutical Sciences, Royal College of Surgeons in Ireland, St. Stephen's Green, Dublin 2, Ireland
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20
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Rosa-Neto P, Doudet DJ, Cumming P. Gradients of dopamine D1- and D2/3-binding sites in the basal ganglia of pig and monkey measured by PET. Neuroimage 2004; 22:1076-83. [PMID: 15219579 DOI: 10.1016/j.neuroimage.2004.03.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2003] [Revised: 03/02/2004] [Accepted: 03/03/2004] [Indexed: 11/19/2022] Open
Abstract
The distributions of dopamine D1 and D2/3 binding sites in living brain have not been compared directly using positron emission tomography (PET). To map these binding sites, we first optimized methods for the assay of dopamine receptors in brain of Göttingen miniature pigs. The binding potentials (pB) of [11C]NNC 112 for dopamine D1 receptors and [11C]raclopride for dopamine D2/3 receptors were calculated in pig striatum volumes of interest using metabolite corrected arterial inputs or using cerebellum as a non-binding reference region. Depending upon the method for quantitation, the pB for [11C]NNC 112 was 1.2-5.1 in pig striatum, whereas the pB for [11C]raclopride was 1.0-1.8. We used the reference tissue method of Logan to calculate pB maps for the two tracers. The maps were co-registered to the common stereotaxic space for the pig brain and normalized to a global mean for pB in striatum; t-maps showed that dopamine D1 binding was relatively more abundant in the ventral-anterior striatum of the pig, while dopamine D2/3 binding was greater in the dorsal striatum. Similar comparisons were made for the pBs of [11C]Sch 23390 for dopamine D1 receptors and for [11C]raclopride in the brain of six rhesus monkeys. The magnitudes of pB for both binding sites in monkey brain were close to those in the pig. Consistent with the pig results, there were distinct gradients in the distributions of the two binding sites in monkey brain: D1 binding predominated in the ventral striatum, whereas D2/3 binding was relatively greater in the dorsal-posterior striatum. Gradients of dopamine receptor concentration within the striatum may be a general phenomenon of mammalian brain.
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Affiliation(s)
- Pedro Rosa-Neto
- PET Centre, Aarhus University Hospitals, and Centre of Functionally Integrative Neuroscience (CFIN), Aarhus University, Aarhus, Denmark.
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21
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Abstract
This article presents a conceptual review of the genetic underpinnings of psychotic mood disorders. Both unipolar and bipolar forms of mood disorder sometimes feature psychotic symptoms. Some evidence from epidemiological research suggests that psychotic forms of mood disorder specifically might be heritable. Linkage studies of mood disorders in general have also provided some support for that notion, as have associated studies involving serotonin and dopamine genes and psychotic mood disorder. Some research suggests there might be a genetic connection between schizophrenia and bipolar disorder, undermining the Kraepelinian dichotomous classification of the psychoses. Future research should continue to examine psychotic forms of mood disorder using both epidemiological and molecular approaches.
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Affiliation(s)
- Ming T Tsuang
- Harvard Medical School Department of Psychiatry at the Massachusetts Mental Health Center, 74 Fenwood Road, Boston, MA, USA.
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