1
|
Nishiyama K, Suzuki H, Harasawa T, Suzuki N, Kurimoto E, Kawai T, Maruyama M, Komatsu H, Sakuma K, Shimizu Y, Shimojo M. FTBMT, a Novel and Selective GPR52 Agonist, Demonstrates Antipsychotic-Like and Procognitive Effects in Rodents, Revealing a Potential Therapeutic Agent for Schizophrenia. J Pharmacol Exp Ther 2017; 363:253-264. [PMID: 28851764 DOI: 10.1124/jpet.117.242925] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 08/23/2017] [Indexed: 01/23/2023] Open
Abstract
GPR52 is a Gs-coupled G protein-coupled receptor that is predominantly expressed in the striatum and nucleus accumbens (NAc) and was recently proposed as a potential therapeutic target for schizophrenia. In the current study, we investigated the in vitro and in vivo pharmacologic activities of a novel GPR52 agonist, 4-(3-(3-fluoro-5-(trifluoromethyl)benzyl)-5-methyl-1H-1,2,4-triazol-1-yl)-2-methylbenzamide (FTBMT). FTBMT functioned as a selective GPR52 agonist in vitro and in vivo, as demonstrated by the activation of Camp signaling in striatal neurons. FTBMT inhibited MK-801-induced hyperactivity, an animal model for acute psychosis, without causing catalepsy in mice. The c-fos expression also revealed that FTBMT preferentially induced neuronal activation in the shell of the Nac compared with the striatum, thereby supporting its antipsychotic-like activity with less catalepsy. Furthermore, FTBMT improved recognition memory in a novel object-recognition test and attenuated MK-801-induced working memory deficits in a radial arm maze test in rats. These recognitive effects were supported by the results of FTBMT-induced c-fos expression in the brain regions related to cognition, including the medial prefrontal cortex, entorhinal cortex, and hippocampus. Taken together, these findings suggest that FTBMT shows antipsychotic and recognitive properties without causing catalepsy in rodents. Given its unique pharmacologic profile, which differs from that of current antipsychotics, FTBMT may provide a new therapeutic option for the treatment of positive and cognitive symptoms of schizophrenia.
Collapse
Affiliation(s)
- Keiji Nishiyama
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Hirobumi Suzuki
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Toshiya Harasawa
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Noriko Suzuki
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Emi Kurimoto
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Takayuki Kawai
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Minoru Maruyama
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Hidetoshi Komatsu
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Kensuke Sakuma
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Yuji Shimizu
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| | - Masato Shimojo
- CNS Drug Discovery Unit, Research (K.N., H.S., T.H., N.S., E.K., T.K., M.M., H.K., Y.S., M.S.) and Regenerative Medicine Unit (K.S.), Takeda Pharmaceutical Company Limited, Fujisawa, Japan
| |
Collapse
|
2
|
Morató X, Luján R, López-Cano M, Gandía J, Stagljar I, Watanabe M, Cunha RA, Fernández-Dueñas V, Ciruela F. The Parkinson's disease-associated GPR37 receptor interacts with striatal adenosine A 2A receptor controlling its cell surface expression and function in vivo. Sci Rep 2017; 7:9452. [PMID: 28842709 PMCID: PMC5573386 DOI: 10.1038/s41598-017-10147-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 08/04/2017] [Indexed: 11/24/2022] Open
Abstract
G protein-coupled receptor 37 (GPR37) is an orphan receptor associated to Parkinson’s disease (PD) neuropathology. Here, we identified GPR37 as an inhibitor of adenosine A2A receptor (A2AR) cell surface expression and function in vivo. In addition, we showed that GPR37 and A2AR do oligomerize in the striatum. Thus, a close proximity of GPR37 and A2AR at the postsynaptic level of striatal synapses was observed by double-labelling post-embedding immunogold detection. Indeed, the direct receptor-receptor interaction was further substantiated by proximity ligation in situ assay. Interestingly, GPR37 deletion promoted striatal A2AR cell surface expression that correlated well with an increased A2AR agonist-mediated cAMP accumulation, both in primary striatal neurons and nerve terminals. Furthermore, GPR37−/− mice showed enhanced A2AR agonist-induced catalepsy and an increased response to A2AR antagonist-mediated locomotor activity. Overall, these results revealed a key role for GPR37 controlling A2AR biology in the striatum, which may be relevant for PD management.
Collapse
Affiliation(s)
- Xavier Morató
- Unitat de Farmacologia, Departament Patologia i Terapéutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Rafael Luján
- IDINE, Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain
| | - Marc López-Cano
- Unitat de Farmacologia, Departament Patologia i Terapéutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Jorge Gandía
- Unitat de Farmacologia, Departament Patologia i Terapéutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain
| | - Igor Stagljar
- Donnelly Centre, Department of Molecular Genetics, Department of Biochemistry, University of Toronto, Toronto, M5S 3E1, Canada
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University School of Medicine, Sapporo, 060-0818, Japan
| | - Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Víctor Fernández-Dueñas
- Unitat de Farmacologia, Departament Patologia i Terapéutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain. .,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain.
| | - Francisco Ciruela
- Unitat de Farmacologia, Departament Patologia i Terapéutica Experimental, Facultat de Medicina, IDIBELL, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain. .,Institut de Neurociències, Universitat de Barcelona, Barcelona, Spain.
| |
Collapse
|
3
|
Yin SB, Zhang XG, Chen S, Yang WT, Zheng XW, Zheng GQ. Adenosine A 2A Receptor Gene Knockout Prevents l-3,4-Dihydroxyphenylalanine-Induced Dyskinesia by Downregulation of Striatal GAD67 in 6-OHDA-Lesioned Parkinson's Mice. Front Neurol 2017; 8:88. [PMID: 28377741 PMCID: PMC5359221 DOI: 10.3389/fneur.2017.00088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 02/24/2017] [Indexed: 11/29/2022] Open
Abstract
l-3,4-Dihydroxyphenylalanine (l-DOPA) remains the primary pharmacological agent for the symptomatic treatment of Parkinson’s disease (PD). However, the development of l-DOPA-induced dyskinesia (LID) limits the long-term use of l-DOPA for PD patients. Some data have reported that adenosine A2A receptor (A2AR) antagonists prevented LID in animal model of PD. However, the mechanism in which adenosine A2AR blockade alleviates the symptoms of LID has not been fully clarified. Here, we determined to knock out (KO) the gene of A2AR and explored the possible underlying mechanisms implicated in development of LID in a mouse model of PD. A2AR gene KO mice were unilaterally injected into the striatum with 6-hydroxydopamine (6-OHDA) in order to damage dopamine neurons on one side of the brain. 6-OHDA-lesioned mice were then injected once daily for 21 days with l-DOPA. Abnormal involuntary movements (AIMs) were evaluated on days 3, 8, 13, and 18 after l-DOPA administration, and real-time polymerase chain reaction and immunohistochemistry for glutamic acid decarboxylase (GAD) 65 and GAD67 were performed. We found that A2AR gene KO was effective in reducing AIM scores and accompanied with decrease of striatal GAD67, rather than GAD65. These results demonstrated that the possible mechanism involved in alleviation of AIM symptoms by A2AR gene KO might be through reducing the expression of striatal GAD67.
Collapse
Affiliation(s)
- Su-Bing Yin
- Department of Neurology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| | - Xiao-Guang Zhang
- Department of Neurology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| | - Shuang Chen
- Department of Neurology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| | - Wen-Ting Yang
- Department of Neurology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| | - Xia-Wei Zheng
- Department of Neurology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| | - Guo-Qing Zheng
- Department of Neurology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University , Wenzhou , China
| |
Collapse
|
4
|
Jones N, Bleickardt C, Mullins D, Parker E, Hodgson R. A2A receptor antagonists do not induce dyskinesias in drug-naive or L-dopa sensitized rats. Brain Res Bull 2013; 98:163-9. [PMID: 23838432 DOI: 10.1016/j.brainresbull.2013.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 06/28/2013] [Accepted: 07/01/2013] [Indexed: 12/26/2022]
Abstract
L-dopa, the precursor to dopamine, is currently the gold standard treatment for Parkinson's disease (PD). However, chronic exposure is associated with L-dopa-induced dyskinesias (LIDs), a serious side effect characterized by involuntary movements. Adenosine A2A receptor antagonists have been studied as a novel non-dopaminergic PD treatment. Because A2A receptor antagonists do not act on dopamine receptors, it has been hypothesized that they will not induce dyskinesias characteristic of L-dopa. To test this hypothesis in a rodent model, the A2A receptor antagonists SCH 412348 (3 mg/kg), vipadenant (10 mg/kg), caffeine (30 mg/kg), or istradefylline (3 mg/kg) were chronically (19-22 days) administered to Sprague Dawley rats, and dyskinetic behaviors were scored across this chronic dosing paradigm. Unlike L-dopa, there was no evidence of dyskinetic activity resulting from any of the four A2A receptor antagonists tested. When delivered to animals previously sensitized with L-dopa (6 mg/kg), SCH 412348, vipadenant, caffeine or istradefylline treatment produced no dyskinesias. When administered in combination with L-dopa (6 mg/kg), SCH 412348 (3 mg/kg) neither exacerbated nor prevented the induction of LIDs over the course of 19 days of treatment. Collectively, our data indicate that A2A receptor antagonists are likely to have a reduced dyskinetic liability relative to L-dopa but do not block dyskinesias when coadministered with L-dopa. Clinical studies are required to fully understand the dyskinesia profiles of A2A receptor antagonists.
Collapse
Affiliation(s)
- N Jones
- Merck Sharp & Dohme Corp., Whitehouse Station, NJ, USA
| | | | | | | | | |
Collapse
|
5
|
Zarrindast MR, Ghadimi M, Ramezani-Tehrani B, Sahebgharani M. EFFECT OF GABA RECEPTOR AGONISTS OR ANTAGONISTS ON MORPHINE-INDUCED STRAUB TAIL IN MICE. Int J Neurosci 2009; 116:963-73. [PMID: 16861161 DOI: 10.1080/00207450600550428] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The effects of GABA receptor agents on Straub tail induced by morphine were investigated in mice. Subcutaneous injection of different doses of morphine (10-60 mg/kg) induced a dose-dependent Straub tail in mice. Maximum response was obtained with 40 mg/kg of the drug, 30 min after the drug administration. The morphine response was decreased by subcutaneous injection of naloxone (0.5-2 mg/kg). Intraperitoneal administration of different doses of baclofen (2-8 mg/kg) reduced Straub tail induced by morphine (40 mg/kg). The response of baclofen was decreased by Intraperitoneal injection of CGP35348 (150 mg/kg). CGP35348 by itself did not elicit any response. Different Intraperitoneally doses of muscimol (1-4 mg/kg) bicuculline (1-3 mg/kg), or picrotoxin (1-3 mg/kg) also reduced morphine effect. The effect of muscimol was not altered by bicuculline pretreatment. It is concluded that both GABAA and GABAB receptor activation reduced Straub tail induced by morphine.
Collapse
Affiliation(s)
- M R Zarrindast
- Department of Pharmacology, Medical School, Tehran University of Medical Sciences, Iran.
| | | | | | | |
Collapse
|
6
|
Ishiwari K, Madson LJ, Farrar AM, Mingote SM, Valenta JP, DiGianvittorio MD, Frank LE, Correa M, Hockemeyer J, Müller C, Salamone JD. Injections of the selective adenosine A2A antagonist MSX-3 into the nucleus accumbens core attenuate the locomotor suppression induced by haloperidol in rats. Behav Brain Res 2007; 178:190-9. [PMID: 17223207 PMCID: PMC2806669 DOI: 10.1016/j.bbr.2006.12.020] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2006] [Revised: 12/11/2006] [Accepted: 12/14/2006] [Indexed: 11/18/2022]
Abstract
There is considerable evidence of interactions between adenosine A2A receptors and dopamine D2 receptors in striatal areas, and antagonists of the A2A receptor have been shown to reverse the motor effects of DA antagonists in animal models. The D2 antagonist haloperidol produces parkinsonism in humans, and also induces motor effects in rats, such as suppression of locomotion. The present experiments were conducted to study the ability of the adenosine A2A antagonist MSX-3 to reverse the locomotor effects of acute or subchronic administration of haloperidol in rats. Systemic (i.p.) injections of MSX-3 (2.5-10.0 mg/kg) were capable of attenuating the suppression of locomotion induced by either acute or repeated (i.e., 14 day) administration of 0.5 mg/kg haloperidol. Bilateral infusions of MSX-3 directly into the nucleus accumbens core (2.5 microg or 5.0 microg in 0.5 microl per side) produced a dose-related increase in locomotor activity in rats treated with 0.5 mg/kg haloperidol either acutely or repeatedly. There were no overall significant effects of MSX-3 infused directly into the dorsomedial nucleus accumbens shell or the ventrolateral neostriatum. These results indicate that antagonism of adenosine A2A receptors can attenuate the locomotor suppression produced by DA antagonism, and that this effect may be at least partially mediated by A2A receptors in the nucleus accumbens core. These studies suggest that adenosine and dopamine systems interact to modulate the locomotor and behavioral activation functions of nucleus accumbens core.
Collapse
Affiliation(s)
- Keita Ishiwari
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
| | - Lisa J. Madson
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
| | - Andrew M. Farrar
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
| | - Susana M. Mingote
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
| | - John P. Valenta
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
| | | | - Lauren E. Frank
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
| | - Merce Correa
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
- Area de Psicobiol., Department of Psicologia, Universitat de Jaume I, Castello, Spain
| | - Jörg Hockemeyer
- Universität Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie, Poppelsdorf, Bonn, Germany
| | - Christa Müller
- Universität Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie, Poppelsdorf, Bonn, Germany
| | - John D. Salamone
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, United States
| |
Collapse
|
7
|
Pan HZ, Chen HH. Hyperalgesia, low-anxiety, and impairment of avoidance learning in neonatal caffeine-treated rats. Psychopharmacology (Berl) 2007; 191:119-25. [PMID: 17096081 DOI: 10.1007/s00213-006-0613-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Accepted: 10/01/2006] [Indexed: 11/27/2022]
Abstract
RATIONALE The nonselective adenosine receptor antagonist caffeine is used clinically to treat apnea in preterm infants. The brain developmental stage of preterm infants is usually at a period of rapid brain growth, referred as brain growth spurt, which occurs during early postnatal life in rats and is highly sensitive to central nervous system (CNS) acting drugs. OBJECTIVES The aim of this work was to study whether caffeine treatment during brain growth spurt produces long-term effects on the adenosine receptor-regulated behaviors including nociception, anxiety, learning, and memory. METHODS Neonatal male and female Sprague-Dawley rats were administered either deionized water or caffeine (15-20 mg kg(-1) day(-1)) through gavage (0.05 ml/10 g) over postnatal days (PN) 2-6. The hot-plate test, elevated plus-maze, dark-light transition test, and step-through inhibitory avoidance learning task were examined in juvenile rats. Furthermore, the responses to adenosine A(1) receptor agonist N(6)-cyclopentyladenosine (CPA)-induced hypothermia and A(2A) receptor agonist CGS21680-induced locomotor depression were also compared. RESULTS Caffeine-treated rats showed hyperalgesia in hot-plate test, less anxiety than controls in the elevated plus-maze and dark-light transition, and impairment in step-through avoidance learning test. Moreover, the responses to CPA-induced hypothermia and CGS21680-induced locomotor depression were enhanced in caffeine-treated rats. CONCLUSION These results indicate that caffeine exposure during brain growth spurt alters the adenosine receptor-regulated behaviors and the responsiveness to adenosine agonists, suggesting the risk of adenosine receptor-related behavioral dysfunction may exist in preterm newborns treated for apnea with caffeine.
Collapse
Affiliation(s)
- Hong-Zhen Pan
- Institute of Pharmacology and Toxicology, Tzu Chi University, 701, section 3, Chung-Yang Road, Hualien 970, Taiwan
| | | |
Collapse
|
8
|
Meyer L, Caston J. Repeated stress alters caffeine action on motor coordination in C57Bl6/J male mice. Brain Res 2005; 1039:171-6. [PMID: 15781059 DOI: 10.1016/j.brainres.2005.01.053] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Revised: 01/19/2005] [Accepted: 01/19/2005] [Indexed: 10/25/2022]
Abstract
This study was aimed to evaluate the effects of stress on caffeine action on motor coordination in mice. For 6 consecutive days, the mice were subjected to three different stressors. Saline or caffeine (30, 60 or 120 mg kg(-1)) was i.p. administered after the last stressful experience, then the animals were behaviorally tested in the holeboard. Their stumbling frequency was compared to that of unstressed mice injected with either saline or caffeine. (1) There was a strong trend for stress to impair motor coordination. (2) In unstressed mice, caffeine induced a linear dose-dependent increase of stumbling frequency. (3) Stress decreased the stumbling frequency induced by the highest dose of caffeine. The results are discussed in terms of interaction of stress and caffeine on dopaminergic and GABAergic systems.
Collapse
Affiliation(s)
- L Meyer
- Laboratoire PSY.CO, UPRES EA 1780, Equipe Plasticité Cérébrale, Faculté des Sciences-Université de Rouen, 76821 Mont-Saint-Aignan Cedex, France.
| | | |
Collapse
|
9
|
Correa M, Wisniecki A, Betz A, Dobson DR, O'Neill MF, O'Neill MJ, Salamone JD. The adenosine A2A antagonist KF17837 reverses the locomotor suppression and tremulous jaw movements induced by haloperidol in rats: possible relevance to parkinsonism. Behav Brain Res 2004; 148:47-54. [PMID: 14684247 DOI: 10.1016/s0166-4328(03)00178-5] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent evidence indicates that adenosine A2A receptors modulate the activity of striatal neurons, and that antagonists of this receptor may have actions in various animal models related to motor function. Four experiments were conducted to study the effects of systemic injections of the adenosine A2A antagonist KF17837 on the behavioral effects produced by repeated administration of the dopamine (DA) antagonist haloperidol. In the first two experiments, it was shown that repeated 0.5 mg/kg haloperidol severely suppressed open-field locomotor activity, and that KF17837 (0.0-20.0 mg/kg) did not significantly increase open-field locomotor activity. The third experiment demonstrated that injections of KF17837 (0.0-20.0 mg/kg) completely reversed the suppression of locomotion induced by haloperidol, and also increased rearing behavior in haloperidol-treated rats. Previous research has reported that haloperidol induces tremulous jaw movements that have many of the characteristics of parkinsonian tremor. The fourth experiment demonstrated that i.p. injections of KF17837 (0.0-20.0 mg/kg) also suppressed haloperidol-induced tremulous jaw movements. Taken together, the results of these experiments indicate that adenosine A2A antagonism can reverse the locomotor suppression and tremulous movements induced by DA antagonism. This profile of activity is consistent with the hypothesis that antagonism of adenosine A2A receptors can result in an antiparkinsonian effect in animal models.
Collapse
Affiliation(s)
- M Correa
- Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA
| | | | | | | | | | | | | |
Collapse
|
10
|
Chen JF, Moratalla R, Impagnatiello F, Grandy DK, Cuellar B, Rubinstein M, Beilstein MA, Hackett E, Fink JS, Low MJ, Ongini E, Schwarzschild MA. The role of the D(2) dopamine receptor (D(2)R) in A(2A) adenosine receptor (A(2A)R)-mediated behavioral and cellular responses as revealed by A(2A) and D(2) receptor knockout mice. Proc Natl Acad Sci U S A 2001; 98:1970-5. [PMID: 11172060 PMCID: PMC29366 DOI: 10.1073/pnas.98.4.1970] [Citation(s) in RCA: 180] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2000] [Indexed: 11/18/2022] Open
Abstract
The A(2A)R is largely coexpressed with D(2)Rs and enkephalin mRNA in the striatum where it modulates dopaminergic activity. Activation of the A(2A)R antagonizes D(2)R-mediated behavioral and neurochemical effects in the basal ganglia through a mechanism that may involve direct A(2A)R-D(2)R interaction. However, whether the D(2)R is required for the A(2A)R to exert its neural function is an open question. In this study, we examined the role of D(2)Rs in A(2A)R-induced behavioral and cellular responses, by using genetic knockout (KO) models (mice deficient in A(2A)Rs or D(2)Rs or both). Behavioral analysis shows that the A(2A)R agonist 2-4-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine reduced spontaneous as well as amphetamine-induced locomotion in both D(2) KO and wild-type mice. Conversely, the nonselective adenosine antagonist caffeine and the A(2A)R antagonist 8-(3-chlorostyryl)caffeine produced motor stimulation in mice lacking the D(2)R, although the stimulation was significantly attenuated. At the cellular level, A(2A)R inactivation counteracted the increase in enkephalin expression in striatopallidal neurons caused by D(2)R deficiency. Consistent with the D(2) KO phenotype, A(2A)R inactivation partially reversed both acute D(2)R antagonist (haloperidol)-induced catalepsy and chronic haloperidol-induced enkephalin mRNA expression. Together, these results demonstrate that A(2A)Rs elicit behavioral and cellular responses despite either the genetic deficiency or pharmacological blockade of D(2)Rs. Thus, A(2A)R-mediated neural functions are partially independent of D(2)Rs. Moreover, endogenous adenosine acting at striatal A(2A)Rs may be most accurately viewed as a facilitative modulator of striatal neuronal activity rather than simply as an inhibitory modulator of D(2)R neurotransmission.
Collapse
Affiliation(s)
- J F Chen
- Molecular Neurobiology Laboratory, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
|
12
|
Functional uncoupling of adenosine A(2A) receptors and reduced responseto caffeine in mice lacking dopamine D2 receptors. J Neurosci 2000. [PMID: 10934242 DOI: 10.1523/jneurosci.20-16-05949.2000] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Dopamine D(2) receptors (Rs) and adenosine A(2A)Rs are coexpressed on striatopallidal neurons, where they mediate opposing actions. In agreement with the idea that D(2)Rs tonically inhibit GABA release from these neurons, stimulation-evoked GABA release was significantly greater from striatal/pallidal slices from D(2)R null mutant (D(2)R(-/-)) than from wild-type (D(2)R(+/+)) mice. Release from heterozygous (D(2)R(+/-)) slices was intermediate. However, contrary to predictions that A(2A)R effects would be enhanced in D(2)R-deficient mice, the A(2A)R agonist CGS 21680 significantly increased GABA release only from D(2)R(+/+) slices. CGS 21680 modulation was observed when D(2)Rs were antagonized by raclopride, suggesting that an acute absence of D(2)Rs cannot explain the results. The lack of CGS 21680 modulation in the D(2)R-deficient mice was also not caused by a compensatory downregulation of A(2A)Rs in the striatum or globus pallidus. However, CGS 21680 significantly stimulated cAMP production only in D(2)R(+/+) striatal/pallidal slices. This functional uncoupling of A(2A)Rs in the D(2)R-deficient mice was not explained by reduced expression of G(s), G(olf), or type VI adenylyl cyclase. Locomotor activity induced by the adenosine receptor antagonist caffeine was significantly less pronounced in D(2)R(-/-) mice than in D(2)R(+/+) and D(2)R(+/-) mice, further supporting the idea that D(2)Rs are required for caffeine activation. Caffeine increased c-fos only in D(2)R(-/-) globus pallidus. The present results show that a targeted disruption of the D(2)R reduces coupling of A(2A)Rs on striatopallidal neurons and thereby responses to drugs that act on adenosine receptors. They also reinforce the ideas that D(2)Rs and A(2A)Rs are functionally opposed and that D(2)R-mediated effects normally predominate.
Collapse
|