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Bassareo V, Maccioni R, Talani G, Zuffa S, El Abiead Y, Lorrai I, Kawamura T, Pantis S, Puliga R, Vargiu R, Lecca D, Enrico P, Peana A, Dazzi L, Dorrestein PC, Sanna PP, Sanna E, Acquas E. Receptor and metabolic insights on the ability of caffeine to prevent alcohol-induced stimulation of mesolimbic dopamine transmission. Transl Psychiatry 2024; 14:391. [PMID: 39341817 PMCID: PMC11438888 DOI: 10.1038/s41398-024-03112-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2024] [Revised: 09/19/2024] [Accepted: 09/23/2024] [Indexed: 10/01/2024] Open
Abstract
The consumption of alcohol and caffeine affects the lives of billions of individuals worldwide. Although recent evidence indicates that caffeine impairs the reinforcing properties of alcohol, a characterization of its effects on alcohol-stimulated mesolimbic dopamine (DA) function was lacking. Acting as the pro-drug of salsolinol, alcohol excites DA neurons in the posterior ventral tegmental area (pVTA) and increases DA release in the nucleus accumbens shell (AcbSh). Here we show that caffeine, via antagonistic activity on A2A adenosine receptors (A2AR), prevents alcohol-dependent activation of mesolimbic DA function as assessed, in-vivo, by brain microdialysis of AcbSh DA and, in-vitro, by electrophysiological recordings of pVTA DA neuronal firing. Accordingly, while the A1R antagonist DPCPX fails to prevent the effects of alcohol on DA function, both caffeine and the A2AR antagonist SCH 58261 prevent alcohol-dependent pVTA generation of salsolinol and increase in AcbSh DA in-vivo, as well as alcohol-dependent excitation of pVTA DA neurons in-vitro. However, caffeine also prevents direct salsolinol- and morphine-stimulated DA function, suggesting that it can exert these inhibitory effects also independently from affecting alcohol-induced salsolinol formation or bioavailability. Finally, untargeted metabolomics of the pVTA showcases that caffeine antagonizes alcohol-mediated effects on molecules (e.g. phosphatidylcholines, fatty amides, carnitines) involved in lipid signaling and energy metabolism, which could represent an additional salsolinol-independent mechanism of caffeine in impairing alcohol-mediated stimulation of mesolimbic DA transmission. In conclusion, the outcomes of this study strengthen the potential of caffeine, as well as of A2AR antagonists, for future development of preventive/therapeutic strategies for alcohol use disorder.
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Affiliation(s)
- Valentina Bassareo
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria Monserrato, Monserrato, CA, Italy
| | - Riccardo Maccioni
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA.
| | - Giuseppe Talani
- Institute of Neuroscience - National Research Council (C.N.R.) of Italy, Cagliari, Italy
| | - Simone Zuffa
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA, USA
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA, USA
| | - Yasin El Abiead
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA, USA
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA, USA
| | - Irene Lorrai
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Tomoya Kawamura
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Sofia Pantis
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
- Department of Neurology & Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Roberta Puliga
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria Monserrato, Monserrato, CA, Italy
| | - Romina Vargiu
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria Monserrato, Monserrato, CA, Italy
| | - Daniele Lecca
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria Monserrato, Monserrato, CA, Italy
| | - Paolo Enrico
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Alessandra Peana
- Department of Medical, Surgical and Experimental Sciences, University of Sassari, Sassari, Italy
| | - Laura Dazzi
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria Monserrato, Monserrato, CA, Italy
| | - Pieter C Dorrestein
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA, USA
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, CA, USA
| | - Pietro Paolo Sanna
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Enrico Sanna
- Institute of Neuroscience - National Research Council (C.N.R.) of Italy, Cagliari, Italy
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria Monserrato, Monserrato, CA, Italy
| | - Elio Acquas
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria Monserrato, Monserrato, CA, Italy
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Wei R, Zong F, Dong J, Zhao W, Zhang F, Wang W, Zhao S, Wang Z, Zhang F, Zhang HT. Identification of Phosphodiesterase-7A (PDE7A) as a Novel Target for Reducing Ethanol Consumption in Mice. Int J Neuropsychopharmacol 2024; 27:pyae032. [PMID: 39099166 PMCID: PMC11348009 DOI: 10.1093/ijnp/pyae032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 07/29/2024] [Indexed: 08/06/2024] Open
Abstract
BACKGROUND Ethanol elicits a rapid stimulatory effect and a subsequent, prolonged sedative response, which are potential predictors of EtOH consumption by decreasing adenosine signaling; this phenomenon also reflects the obvious sex difference. cAMP (cyclic Adenosine Monophosphate)-PKA (Protein Kinase A) signaling pathway modulation can influence the stimulatory and sedative effects induced by EtOH in mice. This study's objective is to clarify the role of phosphodiesterase (PDE) in mediating the observed sex differences in EtOH responsiveness between male and female animals. METHODS EtOH was administered i.p. for 7 days to identify the changes in PDE isoforms in response to EtOH treatment. Additionally, EtOH consumption and preference of male and female C57BL/6J mice were assessed using the drinking-in-the-dark and 2-bottle choice tests. Further, pharmacological inhibition of PDE7A heterozygote knockout mice was performed to investigate its effects on EtOH-induced stimulation and sedation in both male and female mice. Finally, Western blotting analysis was performed to evaluate the alterations in cAMP-PKA/Epac2 pathways. RESULTS EtOH administration resulted in an immediate upregulation in PDE7A expression in female mice, indicating a strong association between PDE7A and EtOH stimulation. Through the pharmacological inhibition of PDE7A KD mice, we have demonstrated for the first time, to our knowledge, that PDE7A selectively attenuates EtOH responsiveness and consumption exclusively in female mice, whichmay be associated with the cAMP-PKA/Epac2 pathway and downstream phosphorylation of CREB and ERK1/2. CONCLUSIONS Inhibition or knockdown of PDE7A attenuates EtOH responsivenessand consumption exclusively in female mice, which is associated with alterations in the cAMP-PKA/Epac2 signaling pathways, thereby highlighting its potential as a novel therapeutic target for alcohol use disorder.
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Affiliation(s)
- Ran Wei
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
- Weifang Chinese Medical Hospital, Shandong Second Medical University, Weifang, China
| | - Fangjiao Zong
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
| | - Jiahao Dong
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
- Weifang People’s Hospital, Shandong Second Medical University, Weifang, China
| | - Wei Zhao
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
| | - Fangfang Zhang
- Institude of Pharmacology, Shandong First Medical University and Shandong Academy of Medical Sciences, Tai’an, China
| | - Wei Wang
- Institude of Pharmacology, Shandong First Medical University and Shandong Academy of Medical Sciences, Tai’an, China
| | - Shuang Zhao
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
| | - Ziqi Wang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
| | - Fang Zhang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
| | - Han-Ting Zhang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
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Amaral IM, Scheffauer L, Hofer A, El Rawas R. Protein kinases in natural versus drug reward. Pharmacol Biochem Behav 2022; 221:173472. [PMID: 36244528 DOI: 10.1016/j.pbb.2022.173472] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/27/2022] [Accepted: 10/05/2022] [Indexed: 12/14/2022]
Abstract
Natural and drug rewards act on the same neural pathway, the mesolimbic dopaminergic system. In brain regions such as the nucleus accumbens and ventral tegmental area, drugs of abuse-induced stimulation of signaling pathways can lead to synaptic reshaping within this system. This is believed to be underlying the maladaptive alterations in behaviors associated with addiction. In this review, we discuss animal studies disclosing the implication of several protein kinases, namely protein kinase A (PKA), extracellular signal regulated kinase (ERK) mitogen-activated protein kinases (MAPK), p38 MAPK, and calcium/calmodulin-dependent kinase II (CaMKII), in reward-related brain regions in drug and natural reward. Furthermore, we refer to studies that helped pave the way toward a better understanding of the neurobiology underlying non-drug and drug reward through genetic deletion or brain region-specific pharmacological inhibition of these kinases. Whereas the role of kinases in drug reward has been extensively studied, their implication in natural reward, such as positive social interaction, is less investigated. Discovering molecular candidates, recruited specifically by drug versus natural rewards, can promote the identification of novel targets for the pharmacological treatment of addiction with less off-target effects and being effective when used combined with behavioral-based therapies.
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Affiliation(s)
- Inês M Amaral
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy, Psychosomatics and Medical Psychology, Medical University Innsbruck, Austria.
| | - Laura Scheffauer
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy, Psychosomatics and Medical Psychology, Medical University Innsbruck, Austria.
| | - Alex Hofer
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy, Psychosomatics and Medical Psychology, Medical University Innsbruck, Austria.
| | - Rana El Rawas
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy, Psychosomatics and Medical Psychology, Medical University Innsbruck, Austria.
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Atehortua Martinez LA, Curis E, Mekdad N, Larrieu C, Courtin C, Jourdren L, Blugeon C, Laplanche JL, Megarbane B, Marie-Claire C, Benturquia N. Individual differences in cocaine-induced conditioned place preference in male rats: Behavioral and transcriptomic evidence. J Psychopharmacol 2022; 36:1161-1175. [PMID: 36121009 PMCID: PMC9548661 DOI: 10.1177/02698811221123047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Substance use disorder emerges in a small proportion of drug users and has the characteristics of a chronic relapsing pathology. AIMS Our study aimed to demonstrate and characterize the variability in the expression of the rewarding effects of cocaine in the conditioned place preference (CPP) paradigm. METHODS A cocaine-CPP paradigm in male Sprague-Dawley rats with an extinction period of 12 days and reinstatement was conducted. A statistical model was developed to distinguish rats expressing or not a cocaine-induced place preference. RESULTS Two groups of rats were identified: rats that did express rewarding effects (CPP expression (CPPE), score >102 s) and rats that did not (no CPP expression (nCPPE), score between -85 and 59 s). These two groups did not show significant differences in a battery of behavioral tests. To identify differentially expressed genes in the CPPE and nCPPE groups, a whole-transcriptome ribonucleic acid-sequencing analysis was performed in the nucleus accumbens (NAc) 24 h after the CPP test. Four immediate early genes (Fos, Egr2, Nr4a1, and Zbtb37) were differentially expressed in the NAc of CPPE rats after expression of CPP. Variability in cocaine-induced place preference persisted in the CPPE and nCPPE groups after the extinction and reinstatement phases. Transcriptomic differences observed after reinstatement were distinct from those observed immediately after expression of CPP. CONCLUSION These new findings provide insights into the identification of mechanisms underlying interindividual variability in the response to cocaine's rewarding effects.
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Affiliation(s)
- Luisa Alessandra Atehortua Martinez
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
| | - Emmanuel Curis
- UR 7537 BioSTM, Université Paris Cité, Paris, France
- Laboratoire d’Hématologie, Hôpital Lariboisière, APHP, Paris, France
| | - Nawel Mekdad
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
| | - Claire Larrieu
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
| | - Cindie Courtin
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
| | - Laurent Jourdren
- Genomic Facility, Institut de Biologie de l’École Normale Supérieure, École Normale Supérieure, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, PSL Research University, Paris, France
| | - Corinne Blugeon
- Genomic Facility, Institut de Biologie de l’École Normale Supérieure, École Normale Supérieure, Centre National pour la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, PSL Research University, Paris, France
| | - Jean-Louis Laplanche
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
| | - Bruno Megarbane
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
| | - Cynthia Marie-Claire
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
| | - Nadia Benturquia
- Institut National de la Santé et de la Recherche Médicale UMR-S 1144, Optimisation Thérapeutique en Neuropsychopharmacologie, Université Paris Cité, Paris, France
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Lopatynska-Mazurek M, Antolak A, Grochecki P, Gibula-Tarlowska E, Bodzon-Kulakowska A, Listos J, Kedzierska E, Suder P, Silberring J, Kotlinska JH. Rapamycin Improves Spatial Learning Deficits, Vulnerability to Alcohol Addiction and Altered Expression of the GluN2B Subunit of the NMDA Receptor in Adult Rats Exposed to Ethanol during the Neonatal Period. Biomolecules 2021; 11:biom11050650. [PMID: 33924998 PMCID: PMC8147055 DOI: 10.3390/biom11050650] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/23/2021] [Accepted: 04/24/2021] [Indexed: 12/18/2022] Open
Abstract
Ethanol exposure during pregnancy alters the mammalian target of rapamycin (mTOR) signaling pathway in the fetal brain. Hence, in adult rats exposed to ethanol during the neonatal period, we investigated the influence of rapamycin, an mTOR Complex 1 (mTORC1) inhibitor, on deficits in spatial memory and reversal learning in the Barnes maze task, as well as the ethanol-induced rewarding effects (1.0 or 1.5 g/kg) using the conditioning place preference (CPP) paradigm. Rapamycin (3 and 10 mg/kg) was given before intragastric ethanol (5 g/kg/day) administration at postnatal day (PND)4–9 (an equivalent to the third trimester of human pregnancy). Spatial memory/reversal learning and rewarding ethanol effect were evaluated in adult (PND60–70) rats. Additionally, the impact of rapamycin pre-treatment on the expression of the GluN2B subunit of NMDA receptor in the brain was assessed in adult rats. Our results show that neonatal ethanol exposure induced deficits in spatial memory and reversal learning in adulthood, but the reversal learning outcome may have been due to spatial learning impairments rather than cognitive flexibility impairments. Furthermore, in adulthood the ethanol treated rats were also more sensitive to the rewarding effect of ethanol than the control group. Rapamycin prevented the neonatal effect of ethanol and normalized the GluN2B down-regulation in the hippocampus and the prefrontal cortex, as well as normalized this subunit’s up-regulation in the striatum of adult rats. Our results suggest that rapamycin and related drugs may hold promise as a preventive therapy for fetal alcohol spectrum disorders.
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Affiliation(s)
- Malgorzata Lopatynska-Mazurek
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (M.L.-M.); (P.G.); (E.G.-T.); (J.L.); (E.K.)
| | - Anna Antolak
- Department of Analytical Chemistry and Biochemistry, Faculty of Materials Sciences and Ceramics, AGH University of Science and Technology, Mickiewicza 30 Ave., 30-059 Krakow, Poland; (A.A.); (A.B.-K.); (P.S.); (J.S.)
| | - Pawel Grochecki
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (M.L.-M.); (P.G.); (E.G.-T.); (J.L.); (E.K.)
| | - Ewa Gibula-Tarlowska
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (M.L.-M.); (P.G.); (E.G.-T.); (J.L.); (E.K.)
| | - Anna Bodzon-Kulakowska
- Department of Analytical Chemistry and Biochemistry, Faculty of Materials Sciences and Ceramics, AGH University of Science and Technology, Mickiewicza 30 Ave., 30-059 Krakow, Poland; (A.A.); (A.B.-K.); (P.S.); (J.S.)
| | - Joanna Listos
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (M.L.-M.); (P.G.); (E.G.-T.); (J.L.); (E.K.)
| | - Ewa Kedzierska
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (M.L.-M.); (P.G.); (E.G.-T.); (J.L.); (E.K.)
| | - Piotr Suder
- Department of Analytical Chemistry and Biochemistry, Faculty of Materials Sciences and Ceramics, AGH University of Science and Technology, Mickiewicza 30 Ave., 30-059 Krakow, Poland; (A.A.); (A.B.-K.); (P.S.); (J.S.)
| | - Jerzy Silberring
- Department of Analytical Chemistry and Biochemistry, Faculty of Materials Sciences and Ceramics, AGH University of Science and Technology, Mickiewicza 30 Ave., 30-059 Krakow, Poland; (A.A.); (A.B.-K.); (P.S.); (J.S.)
| | - Jolanta H. Kotlinska
- Department of Pharmacology and Pharmacodynamics, Medical University, Chodzki 4A, 20-093 Lublin, Poland; (M.L.-M.); (P.G.); (E.G.-T.); (J.L.); (E.K.)
- Correspondence: ; Tel.: +48-81-4487255
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Amaral IM, Lemos C, Cera I, Dechant G, Hofer A, El Rawas R. Involvement of cAMP-Dependent Protein Kinase in the Nucleus Accumbens in Cocaine Versus Social Interaction Reward. Int J Mol Sci 2020; 22:E345. [PMID: 33396297 PMCID: PMC7794935 DOI: 10.3390/ijms22010345] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 12/24/2020] [Accepted: 12/28/2020] [Indexed: 12/21/2022] Open
Abstract
Evidence suggests that PKA activity in the nucleus accumbens (NAc) plays an essential role in reward-related learning. In this study, we investigated whether PKA is differentially involved in the expression of learning produced by either natural reinforcers or psychostimulants. For that purpose, we inhibited PKA through a bilateral infusion of Rp-cAMPS, a specific PKA inhibitor, directly into the NAc. The effects of PKA inhibition in the NAc on the expression of concurrent conditioned place preference (CPP) for cocaine (drug) and social interaction (natural reward) in rats were evaluated. We found that PKA inhibition increased the expression of cocaine preference. This effect was not due to altered stress levels or decreased social reward. PKA inhibition did not affect the expression of natural reward as intra-NAc Rp-cAMPS infusion did not affect expression of social preference. When rats were trained to express cocaine or social interaction CPP and tested for eventual persisting preference 7 and 14 days after CPP expression, cocaine preference was persistent, but social preference was abolished after the first test. These results suggest that PKA in the NAc is involved in drug reward learning that might lead to addiction and that only drug, but not natural, reward is persistent.
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Affiliation(s)
- Inês M. Amaral
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy and Psychosomatics, Medical University Innsbruck, 6020 Innsbruck, Austria; (I.M.A.); (C.L.); (A.H.)
| | - Cristina Lemos
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy and Psychosomatics, Medical University Innsbruck, 6020 Innsbruck, Austria; (I.M.A.); (C.L.); (A.H.)
| | - Isabella Cera
- Institute for Neuroscience, Medical University Innsbruck, 6020 Innsbruck, Austria; (I.C.); (G.D.)
| | - Georg Dechant
- Institute for Neuroscience, Medical University Innsbruck, 6020 Innsbruck, Austria; (I.C.); (G.D.)
| | - Alex Hofer
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy and Psychosomatics, Medical University Innsbruck, 6020 Innsbruck, Austria; (I.M.A.); (C.L.); (A.H.)
| | - Rana El Rawas
- Division of Psychiatry I, Department of Psychiatry, Psychotherapy and Psychosomatics, Medical University Innsbruck, 6020 Innsbruck, Austria; (I.M.A.); (C.L.); (A.H.)
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Porru S, Maccioni R, Bassareo V, Peana AT, Salamone JD, Correa M, Acquas E. Effects of caffeine on ethanol-elicited place preference, place aversion and ERK phosphorylation in CD-1 mice. J Psychopharmacol 2020; 34:1357-1370. [PMID: 33103552 DOI: 10.1177/0269881120965892] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Epidemiological studies indicate a rise in the combined consumption of caffeinated and alcoholic beverages, which can lead to increased risk of alcoholic-beverage overconsumption. However, the effects of the combination of caffeine and ethanol in animal models related to aspects of drug addiction are still underexplored. AIMS To characterize the pharmacological interaction between caffeine and ethanol and establish if caffeine can affect the ability of ethanol (2 g/kg) to elicit conditioned place preference and conditioned place aversion, we administered caffeine (3 or 15 mg/kg) to male CD-1 mice before saline or ethanol. Moreover, we determined if these doses of caffeine could affect ethanol (2 g/kg) elicited extracellular signal-regulated kinase phosphorylation in brain areas, nucleus accumbens, bed nucleus of stria terminalis, central nucleus of the amygdala, and basolateral amygdala, previously associated with this type of associative learning. RESULTS In the place-conditioning paradigm, caffeine did not have an effect on its own, whereas ethanol elicited significant conditioned-place preference and conditioned-place aversion. Caffeine (15 mg/kg) significantly prevented the acquisition of ethanol-elicited conditioned-place preference and, at both doses, also prevented the acquisition of ethanol-elicited conditioned-place aversion. Moreover, both doses of caffeine also prevented ethanol-elicited extracellular signal-regulated kinase phosphorylation expression in all brain areas examined. CONCLUSIONS The present data indicate a functional antagonistic action of caffeine and ethanol on associative learning and extracellular signal-regulated kinase phosphorylation after an acute interaction. These results could provide exciting grounds for further studies, also in a translational perspective, of their pharmacological interaction modulating other processes involved in drug consumption and addiction.
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Affiliation(s)
- Simona Porru
- Department of Life and Environmental Sciences, University of Cagliari, Monserrato, Italy.,Department of Psychobiology, University Jaume I, Castelló, Spain
| | - Riccardo Maccioni
- Department of Life and Environmental Sciences, University of Cagliari, Monserrato, Italy
| | - Valentina Bassareo
- Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Alessandra T Peana
- Department of Chemistry and Pharmacy, University of Sassari, Sassari, Italy
| | - John D Salamone
- Department of Psychological Sciences, University of Connecticut, Storrs, USA
| | - Mercè Correa
- Department of Psychobiology, University Jaume I, Castelló, Spain
| | - Elio Acquas
- Department of Life and Environmental Sciences, University of Cagliari, Monserrato, Italy.,Centre of Excellence on Neurobiology of Addiction, University of Cagliari, Cagliari, Italy
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8
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Lee SJ, Chen Y, Lodder B, Sabatini BL. Monitoring Behaviorally Induced Biochemical Changes Using Fluorescence Lifetime Photometry. Front Neurosci 2019; 13:766. [PMID: 31417343 PMCID: PMC6685078 DOI: 10.3389/fnins.2019.00766] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 07/09/2019] [Indexed: 02/06/2023] Open
Abstract
All cells respond to extracellular signals by altering their intracellular biochemical state. In neurons, such signaling regulates many aspects of cell and synapse biology and induces changes that are thought to be important for nervous system development, its adaptation in the face of a changing environment, and ongoing homeostatic maintenance. Although great advances have been made in developing novel fluorescent reporters of intracellular signaling as well as in methods of fluorescence detection for use in freely moving animals, these approaches have generally not been combined. Thus, we know relatively little about how the intracellular biochemical state of neurons, and other cell classes, is dynamically regulated during animals' behavior. Here we describe a single multi-mode fiber based fluorescence lifetime photometry system (FLiP) designed to monitor the state of fluorescence reporters of biochemical state in freely moving animals. We demonstrate the utility of FLiP by monitoring the lifetime of FLIM-AKAR, a genetically encoded fluorescent reporter of PKA phosphorylation, in populations of direct and indirect pathway striatal projection neurons in mice receiving food rewards. We find that the activity of PKA in each pathway is transiently regulated by reward acquisition, with PKA phosphorylation being enhanced and repressed in direct and indirect pathway neurons, respectively. This study demonstrates the power of FLiP to detect changes in biochemical state induced by naturalistic experiences in behaving animals.
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Affiliation(s)
- Suk Joon Lee
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
| | - Yao Chen
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
| | - Bart Lodder
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
- Master Program Neuroscience and Cognition, Graduate School of Life Sciences, Utrecht University and Department of Translational Neuroscience, Brain Center, University Medical Center, Utrecht, Netherlands
| | - Bernardo L. Sabatini
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA, United States
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Casoni F, Galbiati A, Ferini-Strambi L. D3 receptor agonist efficacy in restless legs syndrome. PHARMACOLOGY OF RESTLESS LEGS SYNDROME (RLS) 2019; 84:21-35. [DOI: 10.1016/bs.apha.2019.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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10
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Khaleghzadeh-Ahangar H, Khodagholi F, Shaerzadeh F, Haghparast A. Modulatory role of the intra-accumbal CB1 receptor in protein level of the c-fos and pCREB/CREB ratio in the nucleus accumbens and ventral tegmental area in extinction and morphine seeking in the rats. Brain Res Bull 2018; 142:320-327. [PMID: 30170186 DOI: 10.1016/j.brainresbull.2018.08.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 06/26/2018] [Accepted: 08/25/2018] [Indexed: 11/30/2022]
Abstract
Brain reward and motivation circuit begin from the ventral tegmental area (VTA) that its dopaminergic terminals project to various regions of the brain including the nucleus accumbens (NAc). This reward circuit is influenced by drugs of abuse such as morphine and cannabinoid. The present study tried to investigate the role of the intra-accumbal CB1 receptor in the c-fos level and pCREB/CREB ratio in the NAc and the VTA during reinstatement phase of morphine-induced conditioned place preference (CPP) by western blotting. The present data reveals that intra-accumbal administration of CB1 agonist, WIN55,212-2 (0.5, 1 and 2 mM/0.5 μl DMSO) before/during extinction period of morphine-induced CPP, significantly decreased the NAc and the VTA c-fos protein level in the reinstatement phase; whereas the pre-reinstatement administration of the CB1 agonist, increased the c-fos protein level. Intra-accumbal administration of the CB1 agonist during the extinction period of morphine-induced CPP reduced the pCREB/CREB ratio in the NAc. Also, the present data show that intra-accumbal administration of CB1 antagonist, AM251 (15, 45 and 90 μM/0.5 μl DMSO) during/after extinction period of morphine-induced CPP affects the NAc and the VTA c-fos protein level in the reinstatement phase. Also, intra-NAc microinjection of AM251 during the extinction period reduced pCREB/CREB ratio in these regions. In conclusion, the results presented here provide compelling evidence of the modulation and involvement of the c-fos and the CREB molecules in the cannabinoid-opioid interaction of the brain reward system in the CPP paradigm.
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MESH Headings
- Animals
- Benzoxazines/pharmacology
- Cannabinoid Receptor Modulators/pharmacology
- Cyclic AMP Response Element-Binding Protein/metabolism
- Dose-Response Relationship, Drug
- Drug-Seeking Behavior/drug effects
- Drug-Seeking Behavior/physiology
- Extinction, Psychological/drug effects
- Extinction, Psychological/physiology
- Male
- Morphine/pharmacology
- Morphine Dependence/metabolism
- Morpholines/pharmacology
- Naphthalenes/pharmacology
- Narcotics/pharmacology
- Nucleus Accumbens/drug effects
- Nucleus Accumbens/metabolism
- Phosphorylation
- Piperidines/pharmacology
- Proto-Oncogene Proteins c-fos/metabolism
- Pyrazoles/pharmacology
- Rats, Wistar
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/metabolism
- Ventral Tegmental Area/drug effects
- Ventral Tegmental Area/metabolism
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Affiliation(s)
- Hossein Khaleghzadeh-Ahangar
- Department of Physiology, School of Medicine, Babol University of Medical Sciences, Babol, Iran; Neuroscience Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Fariba Khodagholi
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O. Box 19615-1178, Tehran, Iran
| | - Fatemeh Shaerzadeh
- Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran; Department of Neuroscience, University of Florida College of Medicine and McKnight Brain Institute, Gainesville, FL, 32610, USA
| | - Abbas Haghparast
- Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, P.O. Box 19615-1178, Tehran, Iran.
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Rosas M, Porru S, Sabariego M, Piludu MA, Giorgi O, Corda MG, Acquas E. Effects of morphine on place conditioning and ERK 1/2 phosphorylation in the nucleus accumbens of psychogenetically selected Roman low- and high-avoidance rats. Psychopharmacology (Berl) 2018; 235:59-69. [PMID: 28971231 DOI: 10.1007/s00213-017-4740-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 08/22/2017] [Accepted: 09/13/2017] [Indexed: 11/30/2022]
Abstract
RATIONALE Extracellular signal-regulated kinase (ERK1/2) phosphorylation is critical for neuronal and behavioural functions; in particular, phosphorylated ERK1/2 (pERK1/2) expression in the nucleus accumbens (Acb) of the rat is stimulated by addictive drugs with the exception of morphine, which decreases accumbal ERK1/2 phosphorylation in the Sprague-Dawley and Wistar rats. The psychogenetically selected Roman low- (RLA) and high-avoidance (RHA) rats differ behaviourally and neurochemically in many responses to addictive drugs. In particular, morphine elicits a greater increment in locomotor activity and in dopamine transmission in the Acb of RHA vs RLA rats. However, the effects of morphine on place conditioning (conditioned place preference (CPP)) and ERK1/2 phosphorylation in the Roman lines remain unknown. OBJECTIVES AND METHODS To characterize in the Roman lines the reinforcing properties of morphine (i.e. morphine-elicited CPP acquisition) and the relationship between these properties and its effects on ERK1/2 phosphorylation in the Acb, the behavioural effects of morphine were evaluated in a place-conditioning apparatus and ERK1/2 phosphorylation was assessed by immunohistochemistry in the shell and core subregions of the Acb of rats both acutely administered with morphine or undergoing conditioning. RESULTS Morphine elicited CPP in both Roman lines and decreased pERK1/2 expression in the Acb of RLA but not RHA rats. Such decrease was prevented by conditioning. CONCLUSIONS These findings indicate that the selective breeding of the Roman lines has generated a divergence, in terms of morphine-elicited pERK1/2 expression but not of morphine-elicited CPP, between RLA and RHA rats and sustain the observation that changes in pERK1/2 expression in the Acb are not a requisite for the reinforcing effects of morphine.
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Affiliation(s)
- Michela Rosas
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, 09124, Cagliari, Italy
| | - Simona Porru
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, 09124, Cagliari, Italy
| | - Marta Sabariego
- Neurobiology Section and Center for Neural Circuits and Behavior, Division of Biological Sciences, University of California, San Diego, USA
| | - Maria Antonietta Piludu
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, 09124, Cagliari, Italy
| | - Osvaldo Giorgi
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, 09124, Cagliari, Italy
| | - Maria G Corda
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, 09124, Cagliari, Italy
| | - Elio Acquas
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, 09124, Cagliari, Italy. .,Centre of Excellence on Neurobiology of Addiction, University of Cagliari, Cagliari, Italy.
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12
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Schaefer N, Rotermund C, Blumrich EM, Lourenco MV, Joshi P, Hegemann RU, Jamwal S, Ali N, García Romero EM, Sharma S, Ghosh S, Sinha JK, Loke H, Jain V, Lepeta K, Salamian A, Sharma M, Golpich M, Nawrotek K, Paidi RK, Shahidzadeh SM, Piermartiri T, Amini E, Pastor V, Wilson Y, Adeniyi PA, Datusalia AK, Vafadari B, Saini V, Suárez-Pozos E, Kushwah N, Fontanet P, Turner AJ. The malleable brain: plasticity of neural circuits and behavior - a review from students to students. J Neurochem 2017. [PMID: 28632905 DOI: 10.1111/jnc.14107] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
One of the most intriguing features of the brain is its ability to be malleable, allowing it to adapt continually to changes in the environment. Specific neuronal activity patterns drive long-lasting increases or decreases in the strength of synaptic connections, referred to as long-term potentiation and long-term depression, respectively. Such phenomena have been described in a variety of model organisms, which are used to study molecular, structural, and functional aspects of synaptic plasticity. This review originated from the first International Society for Neurochemistry (ISN) and Journal of Neurochemistry (JNC) Flagship School held in Alpbach, Austria (Sep 2016), and will use its curriculum and discussions as a framework to review some of the current knowledge in the field of synaptic plasticity. First, we describe the role of plasticity during development and the persistent changes of neural circuitry occurring when sensory input is altered during critical developmental stages. We then outline the signaling cascades resulting in the synthesis of new plasticity-related proteins, which ultimately enable sustained changes in synaptic strength. Going beyond the traditional understanding of synaptic plasticity conceptualized by long-term potentiation and long-term depression, we discuss system-wide modifications and recently unveiled homeostatic mechanisms, such as synaptic scaling. Finally, we describe the neural circuits and synaptic plasticity mechanisms driving associative memory and motor learning. Evidence summarized in this review provides a current view of synaptic plasticity in its various forms, offers new insights into the underlying mechanisms and behavioral relevance, and provides directions for future research in the field of synaptic plasticity. Read the Editorial Highlight for this article on page 788. Cover Image for this issue: doi: 10.1111/jnc.13815.
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Affiliation(s)
- Natascha Schaefer
- Institute for Clinical Neurobiology, Julius-Maximilians-University of Wuerzburg, Würzburg, Germany
| | - Carola Rotermund
- German Center of Neurodegenerative Diseases, University of Tuebingen, Tuebingen, Germany
| | - Eva-Maria Blumrich
- Centre for Biomolecular Interactions Bremen, Faculty 2 (Biology/Chemistry), University of Bremen, Bremen, Germany.,Centre for Environmental Research and Sustainable Technology, University of Bremen, Bremen, Germany
| | - Mychael V Lourenco
- Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Pooja Joshi
- Inserm UMR 1141, Robert Debre Hospital, Paris, France
| | - Regina U Hegemann
- Department of Psychology, Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Sumit Jamwal
- Department of Pharmacology, ISF College of Pharmacy, Moga, Punjab, India
| | - Nilufar Ali
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | | | - Sorabh Sharma
- Neuropharmacology Division, Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan, India
| | - Shampa Ghosh
- National Institute of Nutrition (NIN), Indian Council of Medical Research (ICMR), Tarnaka, Hyderabad, India
| | - Jitendra K Sinha
- National Institute of Nutrition (NIN), Indian Council of Medical Research (ICMR), Tarnaka, Hyderabad, India
| | - Hannah Loke
- Hudson Institute of Medical Research, Melbourne, Victoria, Australia.,Department of Molecular and Translational Science, Monash University, Melbourne, Victoria, Australia
| | - Vishal Jain
- Defence Institute of Physiology and Allied Sciences, Delhi, India
| | - Katarzyna Lepeta
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Ahmad Salamian
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Mahima Sharma
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Mojtaba Golpich
- Department of Medicine, University Kebangsaan Malaysia Medical Centre (HUKM), Cheras, Kuala Lumpur, Malaysia
| | - Katarzyna Nawrotek
- Department of Process Thermodynamics, Faculty of Process and Environmental Engineering, Lodz University of Technology, Lodz, Poland
| | - Ramesh K Paidi
- CSIR-Indian Institute of Chemical Biology, Jadavpur, Kolkata, India
| | - Sheila M Shahidzadeh
- Department of Biology, Program in Neuroscience, Syracuse University, Syracuse, New York, USA
| | - Tetsade Piermartiri
- Programa de Pós-Graduação em Neurociências, Universidade Federal de Santa Catarina (UFSC), Florianópolis, Brazil
| | - Elham Amini
- Department of Medicine, University Kebangsaan Malaysia Medical Centre (HUKM), Cheras, Kuala Lumpur, Malaysia
| | - Veronica Pastor
- Instituto de Biología Celular y Neurociencia Prof. Eduardo De Robertis, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Yvette Wilson
- Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
| | - Philip A Adeniyi
- Cell Biology and Neurotoxicity Unit, Department of Anatomy, College of Medicine and Health Sciences, Afe Babalola University, Ado - Ekiti, Ekiti State, Nigeria
| | | | - Benham Vafadari
- Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Vedangana Saini
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Edna Suárez-Pozos
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Toxicología, México
| | - Neetu Kushwah
- Defence Institute of Physiology and Allied Sciences, Delhi, India
| | - Paula Fontanet
- Division of Molecular and Cellular Neuroscience, Institute of Cellular Biology and Neuroscience (IBCN), CONICET-UBA, School of Medicine, Buenos Aires, Argentina
| | - Anthony J Turner
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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13
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Islam F, Xu K, Beninger RJ. Inhibition of Wnt signalling dose-dependently impairs the acquisition and expression of amphetamine-induced conditioned place preference. Behav Brain Res 2017; 326:217-225. [DOI: 10.1016/j.bbr.2017.03.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 03/05/2017] [Accepted: 03/07/2017] [Indexed: 11/16/2022]
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14
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Rosas M, Porru S, Longoni R, Spina L, Peana AT, Collu M, Acquas E. Differential effects of the MEK inhibitor SL327 on the acquisition and expression of ethanol-elicited conditioned place preference and aversion in mice. J Psychopharmacol 2017; 31:105-114. [PMID: 28072036 DOI: 10.1177/0269881116675514] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The involvement of mitogen-activating extracellular kinase (MEK) in place conditioning may vary depending on the motivational sign (positive or negative) and nature (pharmacological or nociceptive) of the unconditioned stimulus (US) and on the phase (acquisition or expression) of the learning process. This study investigated the role of MEK on the acquisition and expression of ethanol-elicited (given 2 g/kg) backward (preference, CPP) and forward (aversion, CPA) place conditioning. The MEK inhibitor SL327 (50 mg/kg for CPP, and 50 and 100 mg/kg for CPA) was administered to CD-1 mice 60 minutes before an ethanol dose (acquisition) or 60 minutes before the post-conditioning tests (expression). Ethanol significantly elicited CPP and CPA; SL327 (50 mg/kg) significantly blocked the acquisition of ethanol-elicited CPP, but not that of CPA. Moreover, SL327 (50 and 100 mg/kg) significantly reduced the expression of ethanol-elicited CPP, but not that of CPA. Finally, SL327 also prevented ethanol-elicited (given 2 g/kg) increases of phosphorylated extracellular signal regulated kinase (pERK)-positive neurons in the nucleus accumbens and other nuclei of the extended amygdala. Overall, these results confirmed the differential involvement of MEK in the acquisition and expression of drug-elicited place conditioning and suggested its differential involvement in distinct behavioral outcomes, depending on the motivational sign of the (same) US and on the significance of the experimental phase of the learning process.
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Affiliation(s)
- Michela Rosas
- 1 Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Simona Porru
- 1 Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Rosanna Longoni
- 1 Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Liliana Spina
- 1 Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Alessandra T Peana
- 2 Department of Chemistry and Pharmacy, University of Sassari, Sassari, Italy
| | - Maria Collu
- 3 Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy.,4 Centre of Excellence in the Neurobiology of Addiction, University of Cagliari, Cagliari, Italy
| | - Elio Acquas
- 1 Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy.,4 Centre of Excellence in the Neurobiology of Addiction, University of Cagliari, Cagliari, Italy
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15
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NMDA receptor antagonism differentially reduces acquisition and expression of sucrose- and fructose-conditioned flavor preferences in BALB/c and SWR mice. Pharmacol Biochem Behav 2016; 148:76-83. [DOI: 10.1016/j.pbb.2016.06.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 05/18/2016] [Accepted: 06/14/2016] [Indexed: 11/17/2022]
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16
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Rosas M, Porru S, Fenu S, Ruiu S, Peana AT, Papale A, Brambilla R, Di Chiara G, Acquas E. Role of nucleus accumbens μ opioid receptors in the effects of morphine on ERK1/2 phosphorylation. Psychopharmacology (Berl) 2016; 233:2943-54. [PMID: 27245230 DOI: 10.1007/s00213-016-4340-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 05/20/2016] [Indexed: 10/21/2022]
Abstract
RATIONALE Despite the critical role attributed to phosphorylated extracellular signal regulated kinase (pERK1/2) in the nucleus accumbens (Acb) in the actions of addictive drugs, the effects of morphine on ERK1/2 phosphorylation in this area are still controversial. OBJECTIVES In order to investigate further this issue, we studied (1) the ability of morphine to affect ERK1/2 phosphorylation in the shell (AcbSh) and core (AcbC) of Sprague-Dawley and Wistar rats and of CD-1 and C57BL/6J mice and (2) the role of dopamine D1 and μ-opioid receptors in Sprague-Dawley rats and CD-1 mice. METHODS The pERK1/2 expression was assessed by immunohistochemistry. RESULTS In rats, morphine decreased AcbSh and AcbC pERK1/2 expression, whereas in mice, increased it preferentially in the AcbSh compared with the AcbC. Systemic SCH 39166 decreased pERK1/2 expression on its own in the AcbSh and AcbC of Sprague-Dawley rats and CD-1 mice; furthermore, in rats, SCH 39166 disclosed the ability of morphine to stimulate pERK1/2 expression. Systemic (rats and mice) and intra-Acb (rats) naltrexone prevented both decreases, in rats, and increases, in mice. CONCLUSIONS These findings confirm the differential effects of morphine in rats and mice Acb and that D1 receptors exert a facilitatory role on ERK1/2 phosphorylation; furthermore, they indicate that, in rats, removal of the D1-dependent pERK1/2 expression discloses the stimulatory influence of morphine on ERK1/2 phosphorylation and that the morphine's ability to decrease pERK1/2 expression is mediated by Acb μ-opioid receptors. Future experiments may disentangle the psychopharmacological significance of the effects of morphine on pERK1/2 in the Acb.
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Affiliation(s)
- Michela Rosas
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, I-09124, Cagliari, Italy
| | - Simona Porru
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, I-09124, Cagliari, Italy
| | - Sandro Fenu
- Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy.,Centre of Excellence on Neurobiology of Addiction, University of Cagliari, Cagliari, Italy
| | - Stefania Ruiu
- Institute of Translational Pharmacology, National Research Council, Pula, Cagliari, Italy
| | - Alessandra T Peana
- Department of Chemistry and Pharmacy, University of Sassari, Sassari, Italy
| | - Alessandro Papale
- Neuroscience and Mental Health Research Institute (NMHRI), Neuroscience Division - School of Biosciences, Cardiff University, Cardiff, UK
| | - Riccardo Brambilla
- Neuroscience and Mental Health Research Institute (NMHRI), Neuroscience Division - School of Biosciences, Cardiff University, Cardiff, UK
| | - Gaetano Di Chiara
- Department of Biomedical Sciences, University of Cagliari, Cagliari, Italy.,Centre of Excellence on Neurobiology of Addiction, University of Cagliari, Cagliari, Italy
| | - Elio Acquas
- Department of Life and Environmental Sciences, University of Cagliari, Via Ospedale, 72, I-09124, Cagliari, Italy. .,Centre of Excellence on Neurobiology of Addiction, University of Cagliari, Cagliari, Italy.
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17
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Salamone JD, Correa M, Yohn S, Lopez Cruz L, San Miguel N, Alatorre L. The pharmacology of effort-related choice behavior: Dopamine, depression, and individual differences. Behav Processes 2016; 127:3-17. [PMID: 26899746 DOI: 10.1016/j.beproc.2016.02.008] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 02/08/2016] [Accepted: 02/12/2016] [Indexed: 12/22/2022]
Abstract
This review paper is focused upon the involvement of mesolimbic dopamine (DA) and related brain systems in effort-based processes. Interference with DA transmission affects instrumental behavior in a manner that interacts with the response requirements of the task, such that rats with impaired DA transmission show a heightened sensitivity to ratio requirements. Impaired DA transmission also affects effort-related choice behavior, which is assessed by tasks that offer a choice between a preferred reinforcer that has a high work requirement vs. less preferred reinforcer that can be obtained with minimal effort. Rats and mice with impaired DA transmission reallocate instrumental behavior away from food-reinforced tasks with high response costs, and show increased selection of low reinforcement/low cost options. Tests of effort-related choice have been developed into models of pathological symptoms of motivation that are seen in disorders such as depression and schizophrenia. These models are being employed to explore the effects of conditions associated with various psychopathologies, and to assess drugs for their potential utility as treatments for effort-related symptoms. Studies of the pharmacology of effort-based choice may contribute to the development of treatments for symptoms such as psychomotor slowing, fatigue or anergia, which are seen in depression and other disorders.
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Affiliation(s)
- John D Salamone
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA.
| | - Merce Correa
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA; Area de Psicobiol., Dept. Psic., Universitat de Jaume I, Castelló 12071, Spain
| | - Samantha Yohn
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA
| | - Laura Lopez Cruz
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA; Area de Psicobiol., Dept. Psic., Universitat de Jaume I, Castelló 12071, Spain
| | - Noemi San Miguel
- Dept. of Psychology Sciences, University of Connecticut, Storrs, CT 06269-1020, USA; Area de Psicobiol., Dept. Psic., Universitat de Jaume I, Castelló 12071, Spain
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18
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Gao J, Zhu N, Feng M, Meng X, Sui N. Intra-nucleus-accumbens SKF38393 improved the impaired acquisition of morphine-conditioned place preference in depression-like rats. Psych J 2015; 1:2-14. [PMID: 26272664 DOI: 10.1002/pchj.9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 04/10/2012] [Indexed: 12/25/2022]
Abstract
Dopaminergic activity in the nucleus accumbens (NAc) and the globus pallidus (GP) is important for the interaction between depression and addiction, with D1- and D2-like receptors playing different roles. Here, we address the effect of depression on morphine reward and its underlying D1- and D2-like effects in the NAc and/or the GP. Novelty-seeking behaviors and the forced open-space swimming test were used to assess a depression-like state in rats that had undergone chronic mild restraint. Depression-like rats were then trained with morphine-induced conditioned place preference (CPP, 3 mg/kg, 4 days), and showed impaired acquisition of the CPP compared with controls. To examine the receptor-specific dopaminergic mechanism underlying this phenomenon, we microinjected the D1-like agonist SKF38393 (1 μg/side) or the D2-like agonist quinpirole (1 μg/side) into the NAc or the GP. The impairment in acquisition of CPP was reversed only by injecting the D1- but not the D2-like agonist in the NAc. These results suggest that enhancement of dopaminergic transmission in the NAc (via D1-like receptors) may be effective in recovering impaired reward learning during a depression-like state.
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Affiliation(s)
- Jun Gao
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.,Graduate University of Chinese Academy of Sciences, Beijing, China
| | - Ning Zhu
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Min Feng
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.,Graduate University of Chinese Academy of Sciences, Beijing, China
| | - Xiaolu Meng
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.,Graduate University of Chinese Academy of Sciences, Beijing, China
| | - Nan Sui
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
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19
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Kim J, Ryu IS, Seo SY, Choe ES. Activation of Protein Kinases and Phosphatases Coupled to Glutamate Receptors Regulates the Phosphorylation State of DARPP32 at Threonine 75 After Repeated Exposure to Cocaine in the Rat Dorsal Striatum in a Ca2+-Dependent Manner. Int J Neuropsychopharmacol 2015; 18:pyv075. [PMID: 26142455 PMCID: PMC4675983 DOI: 10.1093/ijnp/pyv075] [Citation(s) in RCA: 6] [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: 04/28/2015] [Accepted: 07/01/2015] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Phosphorylation state of dopamine- and cAMP-regulated phosphoprotein, molecular weight 32 kDa (DARPP32) is crucial to understand drug-mediated synaptic plasticity. In this study, mechanisms underlying repeated cocaine-stimulated phosphorylation of DARPP32 at threonine 75 (pDARPP32-Thr75) were determined by investigating the hypothesis that activation of protein kinases and phosphatases coupled to glutamate signaling is necessary for the regulation of pDARPP32-Thr75 after repeated cocaine administration. METHODS Intracaudate drug infusions into the rat dorsal striatum followed by Western immunoblot analysis were mainly performed to test this hypothesis. RESULTS The results demonstrated that 7 repeated daily intraperitoneal injections of cocaine (20mg/kg) upregulated the expression of pDARPP32-Thr75. Increases in the cytosolic Ca(2+) concentrations followed by Ca(2+)-dependent protein kinase activation through stimulation of Ca(2+) channels in striatal neurons were necessary for the phosphorylation. Activation of protein phosphatases further regulated the phosphorylation state by deactivating pDARPP32-Thr75 and upstream protein kinases. CONCLUSION These findings suggest that activation of protein kinases and phosphatases coupled to glutamate receptors controls the phosphorylation state of DARPP32-Thr75 after repeated exposure to cocaine in the dorsal striatum in a Ca(2+)-dependent manner.
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Affiliation(s)
| | | | | | - Eun Sang Choe
- Department of Biological Sciences, Pusan National University, Pusan, Korea.
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Rosas M, Zaru A, Sabariego M, Giugliano V, Carboni E, Colombo G, Acquas E. Differential sensitivity of ethanol-elicited ERK phosphorylation in nucleus accumbens of Sardinian alcohol-preferring and -non preferring rats. Alcohol 2014; 48:471-6. [PMID: 24877898 DOI: 10.1016/j.alcohol.2014.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 04/30/2014] [Accepted: 04/30/2014] [Indexed: 01/19/2023]
Abstract
Sardinian alcohol-preferring (sP) and -non preferring (sNP) rats have been selectively bred for opposite ethanol preference and consumption; sP rats represent a validated experimental tool to model several aspects of excessive ethanol drinking in humans. Phosphorylated Extracellular signal-Regulated Kinase (pERK) in dopamine-rich terminal areas plays a critical role in several psychopharmacological effects of addictive drugs, including ethanol. This study was aimed at investigating whether ethanol-elicited ERK activation may differ in key brain areas of ethanol-naïve sP and sNP rats. To this end, the effects of ethanol (0, 0.5, 1, and 2 g/kg, administered intra-gastrically [i.g.]) on ERK phosphorylation were assessed by pERK immunohistochemistry in the shell (AcbSh) and core (AcbC) of the nucleus accumbens (Acb) as well as in the prelimbic (PrL) and infralimbic (IL) prefrontal cortex (PFCx), in the bed nucleus of stria terminalis (BSTL) and in the central nucleus of the amygdala (CeA). Ethanol (1 g/kg) significantly increased pERK immunoreactivity in AcbSh and AcbC of sP but not sNP rats. Conversely, ethanol failed to affect pERK expression in PrL and IL PFCx as well as in BSTL and CeA of both sP and sNP rats. These results suggest that selective breeding of these rat lines results in differential effects of acute ethanol on ERK phosphorylation in brain regions critical for the psychopharmacological effects of ethanol.
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Affiliation(s)
- Michela Rosas
- Pharmaceutical, Pharmacological and Nutraceutical Sciences Section, Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Alessandro Zaru
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, Monserrato, Cagliari, Italy
| | - Marta Sabariego
- Department of Psychology, University of Jaèn, Campus Las Lagunillas s/n Building C-5, 23071 Jaèn, Spain
| | - Valentina Giugliano
- Department of Biomedical Sciences, Division of Neuropsychopharmacology, University of Cagliari, Cagliari, Italy; Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Ezio Carboni
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, Monserrato, Cagliari, Italy; Department of Biomedical Sciences, Division of Neuropsychopharmacology, University of Cagliari, Cagliari, Italy; Centre of Excellence on Neurobiology of Addiction, University of Cagliari, Cagliari, Italy; National Institute of Neuroscience - INN, University of Cagliari, Cagliari, Italy
| | - Giancarlo Colombo
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, Monserrato, Cagliari, Italy
| | - Elio Acquas
- Pharmaceutical, Pharmacological and Nutraceutical Sciences Section, Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy; Centre of Excellence on Neurobiology of Addiction, University of Cagliari, Cagliari, Italy; National Institute of Neuroscience - INN, University of Cagliari, Cagliari, Italy.
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8-pCPT, an Epac activator, impairs conditioned place preference based on nucleus accumbens amphetamine in rats. Acta Neuropsychiatr 2014; 26:104-11. [PMID: 24855888 DOI: 10.1017/neu.2013.37] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVES Dopamine receptor-mediated 3',5'-cyclic adenosine monophosphate (cAMP)-dependent intracellular signalling is important for reward-related learning. cAMP activates cAMP-dependent protein kinase (PKA) and exchange protein directly activated by cAMP (Epac). We tested the hypothesis that reward-related learning may be mediated by Epac. METHODS We evaluated conditioned place preference (CPP) on the basis of nucleus accumbens (NAc) injections of amphetamine (20 μg/0.5 μl/side) plus Sp-adenosine 3',5'-cyclic monophosphorothioate triethylamanine (Sp-cAMPS) (0.1, 1.0, 10, 15, 20 μg/0.5 μl/side), an activator of both PKA and Epac, or amphetamine (20 μg) plus 8-(4-chlorophenylthio)-2'-O-methyladenosine-3',5'-cyclic monophosphate (8-pCPT) (0.73, 1.27, 1.45, 2.89, 5.78, 11.56 μg/0.5 μl/side), an activator of Epac. RESULTS In agreement with previous results, Sp-cAMPS dose-dependently impaired CPP. 8-pCPT impaired CPP at one dose (1.45 μg/0.5 μl/side) and we replicated this effect three times. CONCLUSION The results implicate Epac in the acquisition of reward-related learning.
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Abad S, Fole A, del Olmo N, Pubill D, Pallàs M, Junyent F, Camarasa J, Camins A, Escubedo E. MDMA enhances hippocampal-dependent learning and memory under restrictive conditions, and modifies hippocampal spine density. Psychopharmacology (Berl) 2014; 231:863-74. [PMID: 24158501 DOI: 10.1007/s00213-013-3304-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 09/23/2013] [Indexed: 02/02/2023]
Abstract
OBJECTIVES Addictive drugs produce forms of structural plasticity in the nucleus accumbens and prefrontal cortex. The aim of this study was to investigate the impact of chronic MDMA exposure on pyramidal neurons in the CA1 region of hippocampus and drug-related spatial learning and memory changes. METHODS AND RESULTS Adolescent rats were exposed to saline or MDMA in a regime that mimicked chronic administration. One week later, when acquisition or reference memory was evaluated in a standard Morris water maze (MWM), no differences were obtained between groups. However, MDMA-exposed animals performed better when the MWM was implemented under more difficult conditions. Animals of MDMA group were less anxious and were more prepared to take risks, as in the open field test they ventured more frequently into the central area. We have demonstrated that MDMA caused an increase in brain-derived neurotrophic factor (BDNF) expression. When spine density was evaluated, MDMA-treated rats presented a reduced density when compared with saline, but overall, training increased the total number of spines, concluding that in MDMA-group, training prevented a reduction in spine density or induced its recovery. CONCLUSIONS This study provides support for the conclusion that binge administration of MDMA, known to be associated to neurotoxic damage of hippocampal serotonergic terminals, increases BDNF expression and stimulates synaptic plasticity when associated with training. In these conditions, adolescent rats perform better in a more difficult water maze task under restricted conditions of learning and memory. The effect on this task could be modulated by other behavioural changes provoked by MDMA.
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Affiliation(s)
- Sònia Abad
- Department of Pharmacology and Therapeutic Chemistry (Pharmacology Section) and Institute of Biomedicine (IBUB), University of Barcelona, Avda. Joan XXIII s/n, Barcelona, 08028, Spain
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Ding ZB, Wu P, Luo YX, Shi HS, Shen HW, Wang SJ, Lu L. Region-specific role of Rac in nucleus accumbens core and basolateral amygdala in consolidation and reconsolidation of cocaine-associated cue memory in rats. Psychopharmacology (Berl) 2013; 228:427-37. [PMID: 23494234 DOI: 10.1007/s00213-013-3050-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2012] [Accepted: 02/23/2013] [Indexed: 12/31/2022]
Abstract
RATIONALE AND OBJECTIVES Drug reinforcement and the reinstatement of drug seeking are associated with the pathological processing of drug-associated cue memories that can be disrupted by manipulating memory consolidation and reconsolidation. Ras-related C3 botulinum toxin substrate (Rac) is involved in memory processing by regulating actin dynamics and neural structure plasticity. The nucleus accumbens (NAc) and amygdala have been implicated in the consolidation and reconsolidation of emotional memories. Therefore, we hypothesized that Rac in the NAc and amygdala plays a role in the consolidation and reconsolidation of cocaine-associated cue memory. METHODS Conditioned place preference (CPP) and microinjection of Rac inhibitor NSC23766 were used to determine the role of Rac in the NAc and amygdala in the consolidation and reconsolidation of cocaine-associated cue memory in rats. RESULTS Microinjections of NSC23766 into the NAc core but not shell, basolateral (BLA), or central amygdala (CeA) after each cocaine-conditioning session inhibited the consolidation of cocaine-induced CPP. A microinjection of NSC23766 into the BLA but not CeA, NAc core, or NAc shell immediately after memory reactivation induced by exposure to a previously cocaine-paired context disrupted the reconsolidation of cocaine-induced CPP. The effect of memory disruption on cocaine reconsolidation was specific to reactivated memory, persisted at least 2 weeks, and was not reinstated by a cocaine-priming injection. CONCLUSIONS Our findings indicate that Rac in the NAc core and BLA are required for the consolidation and reconsolidation of cocaine-associated cue memory, respectively.
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Affiliation(s)
- Zeng-Bo Ding
- National Institute on Drug Dependence, Peking University, 38, Xue Yuan Road, Beijing 100191, China
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Glucose-conditioned flavor preference learning requires co-activation of NMDA and dopamine D1-like receptors within the amygdala. Neurobiol Learn Mem 2013; 106:95-101. [PMID: 23887141 DOI: 10.1016/j.nlm.2013.07.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 11/22/2022]
Abstract
The role of amygdala (AMY) NMDA receptor signaling and its interaction with dopamine D1-like receptor signaling in glucose-mediated flavor preference learning was investigated. In Experiment 1, rats were trained with a flavor (CS+) paired with intragastric (IG) 8% glucose infusions and a different flavor (CS-) paired with IG water infusions. In the two-bottle tests (Expression), bilateral intra-AMY injections of the NMDA receptor antagonist, AP5 (0, 5 and 10 nmol/brain), did not block the CS+ preference. In Experiment 2, new rats received intra-AMY injections of either vehicle or AP5 (10 nmol), prior to training sessions with CS+/IG glucose and CS-/IG water. In the two-bottle tests without drug treatment, AP5 rats failed to prefer the CS+ flavor (50%). In Experiments 3, new rats were trained as in Experiment 2 except that, during training, half the rats received AP5 injections (5 nmol) in one side of the AMY and SCH23390 (D1-like receptor antagonist, 6 nmol), in the contralateral AMY (Drug/Drug group). The remaining rats received vehicle injections in one side of the AMY and either AP5 (5 nmol) or SCH23390 (6 nmol) in the contralateral AMY (Drug/Vehicle group). The two-bottle choice tests without drug treatment revealed that, unlike the Drug/Vehicle group (85%), the Drug/Drug group failed to prefer the CS+ flavor (50%). These results reveal an essential role for AMY NMDA receptor activation in the acquisition of flavor preference learning induced by the post-oral reinforcing properties of glucose and demonstrate that such learning is based on co-activation of NMDA and DA D1 receptors within this forebrain structure.
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Peana AT, Acquas E. Behavioral and biochemical evidence of the role of acetaldehyde in the motivational effects of ethanol. Front Behav Neurosci 2013; 7:86. [PMID: 23874276 PMCID: PMC3710953 DOI: 10.3389/fnbeh.2013.00086] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 06/27/2013] [Indexed: 11/13/2022] Open
Abstract
Since Chevens' report, in the early 50's that his patients under treatment with the aldehyde dehydrogenase inhibitor, antabuse, could experience beneficial effects when drinking small volumes of alcoholic beverages, the role of acetaldehyde (ACD) in the effects of ethanol has been thoroughly investigated on pre-clinical grounds. Thus, after more than 25 years of intense research, a large number of studies have been published on the motivational properties of ACD itself as well as on the role that ethanol-derived ACD plays in the effects of ethanol. Accordingly, in particular with respect to the motivational properties of ethanol, these studies were developed following two main strategies: on one hand, were aimed to challenge the suggestion that also ACD may exert motivational properties on its own, while, on the other, with the aid of enzymatic manipulations or ACD inactivation, were aimed to test the hypothesis that ethanol-derived ACD might have a role in ethanol motivational effects. Furthermore, recent evidence significantly contributed to highlight, as possible mechanisms of action of ACD, its ability to commit either dopaminergic and opioidergic transmission as well as to activate the Extracellular signal Regulated Kinase cascade transduction pathway in reward-related brain structures. In conclusion, and despite the observation that ACD seems also to have inherited the elusive nature of its parent compound, the behavioral and biochemical evidence reviewed points to ACD as a neuroactive molecule able, on its own and as ethanol metabolite, to exert motivational effects.
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Affiliation(s)
- Alessandra T Peana
- Department of Chemistry and Pharmacy, University of Sassari Sassari, Italy
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26
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Maney DL. The incentive salience of courtship vocalizations: hormone-mediated 'wanting' in the auditory system. Hear Res 2013; 305:19-30. [PMID: 23665125 DOI: 10.1016/j.heares.2013.04.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 04/12/2013] [Accepted: 04/19/2013] [Indexed: 12/27/2022]
Abstract
Conspecific vocalizations differ from many other sounds in that they have natural incentive salience. Our thinking about auditory responses to vocalizations may therefore benefit from models originally developed to understand reward. According to those models, the brain attributes incentive salience to rewarding stimuli via the activity of monoaminergic neuromodulators. These neuromodulators, in turn, mediate the effects of experience and internal state. Songbirds lend themselves well to this discussion because the natural incentive salience of song is clearly modulated by both factors. Their auditory responses have been well-studied, particularly the song-induced expression of plasticity-associated genes such as ZENK. Here I review evidence that ZENK responses to song are regulated by monoamine neuromodulators, and I interpret this evidence in the context of incentive salience. First, hearing conspecific song engages monoaminergic activity in the auditory system and elsewhere. Second, in females this activity may be regulated by the same hormones that regulate behavioral preferences for song. Finally, much of the evidence thought to implicate neuromodulators in song discrimination and memory suggests that they may affect incentive salience. Expanding the study of incentive salience beyond the mesolimbic reward system may reveal some new ways of thinking about its underlying neural basis. This article is part of a Special Issue entitled "Communication Sounds and the Brain: New Directions and Perspectives".
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Affiliation(s)
- Donna L Maney
- Department of Psychology, 36 Eagle Row, Emory University, Atlanta, GA 30322, USA.
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Salamone JD, Correa M, Nunes EJ, Randall PA, Pardo M. The behavioral pharmacology of effort-related choice behavior: dopamine, adenosine and beyond. J Exp Anal Behav 2012; 97:125-46. [PMID: 22287808 DOI: 10.1901/jeab.2012.97-125] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
For many years, it has been suggested that drugs that interfere with dopamine (DA) transmission alter the "rewarding" impact of primary reinforcers such as food. Research and theory related to the functions of mesolimbic DA are undergoing a substantial conceptual restructuring, with the traditional emphasis on hedonia and primary reward yielding to other concepts and lines of inquiry. The present review is focused upon the involvement of nucleus accumbens DA in effort-related choice behavior. Viewed from the framework of behavioral economics, the effects of accumbens DA depletions and antagonism on food-reinforced behavior are highly dependent upon the work requirements of the instrumental task, and DA-depleted rats show a heightened sensitivity to response costs, especially ratio requirements. Moreover, interference with accumbens DA transmission exerts a powerful influence over effort-related choice behavior. Rats with accumbens DA depletions or antagonism reallocate their instrumental behavior away from food-reinforced tasks that have high response requirements, and show increased selection of low reinforcement/low cost options. Nucleus accumbens DA and adenosine interact in the regulation of effort-related functions, and other brain structures (anterior cingulate cortex, amygdala, ventral pallidum) also are involved. Studies of the brain systems regulating effort-based processes may have implications for understanding drug abuse, as well as symptoms such as psychomotor slowing, fatigue or anergia in depression and other neurological disorders.
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Affiliation(s)
- John D Salamone
- Dept. of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA.
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Effects of protein kinase A inhibitor and activator on rewarding effects of SKF-82958 microinjected into nucleus accumbens shell of ad libitum fed and food-restricted rats. Psychopharmacology (Berl) 2012; 221:589-99. [PMID: 22143580 PMCID: PMC3310955 DOI: 10.1007/s00213-011-2602-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2011] [Accepted: 11/27/2011] [Indexed: 10/14/2022]
Abstract
RATIONALE Previous studies indicate that the rewarding effect of D-1 dopamine receptor stimulation in nucleus accumbens (NAc) shell is greater in food-restricted (FR) than in ad libitum fed (AL) rats. The D-1 receptor is positively coupled to adenylyl cyclase and activates protein kinase A (PKA). OBJECTIVES The purpose of this study was to determine whether PKA is involved in the rewarding effect of D-1 receptor stimulation and, if so, whether it is involved in the enhanced response of FR rats. MATERIALS AND METHODS Rats were stereotaxically implanted with microinjection cannulae in NAc shell and a stimulating electrode in lateral hypothalamus. The rewarding effects of SKF-82958 (1.5 or 3.0 μg, bilaterally) in the presence and absence of PKA inhibitor, Rp-cAMPS (8.9 μg), and PKA activator, Sp-cAMPS (8.9 μg), were assessed using the curve-shift method of intracranial self-stimulation (ICSS). Basal NAc levels of DARPP-32 phosphorylated on Thr34 and Thr75 were measured. RESULTS Rp-cAMPS increased the rewarding effect of SKF-82958 in AL but not FR rats, doubling the ICSS threshold-lowering effect of the 3.0-μg dose. Sp-cAMPS decreased the rewarding effect of SKF-82958 in FR but not AL rats. Levels of phospho-DARPP-32 (Thr75), which inhibits PKA, were higher in FR than AL rats. CONCLUSIONS Results indicate that inhibition of PKA enhances the unconditioned rewarding effect of D-1 receptor stimulation and that decreased PKA may be involved in the effect of FR on drug reward. Evidence for involvement of D-2 receptor-expressing neurons in the enhancing effect of PKA inhibition is discussed.
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Zelek-Molik A, Bielawski A, Kreiner G, Popik P, Vetulani J, Nalepa I. Morphine-induced place preference affects mRNA expression of G protein α subunits in rat brain. Pharmacol Rep 2012; 64:546-57. [DOI: 10.1016/s1734-1140(12)70850-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 02/02/2012] [Indexed: 11/26/2022]
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Correa M, Salamone JD, Segovia KN, Pardo M, Longoni R, Spina L, Peana AT, Vinci S, Acquas E. Piecing together the puzzle of acetaldehyde as a neuroactive agent. Neurosci Biobehav Rev 2012; 36:404-30. [DOI: 10.1016/j.neubiorev.2011.07.009] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 07/14/2011] [Accepted: 07/21/2011] [Indexed: 10/17/2022]
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Thanos PK, Bermeo C, Wang GJ, Volkow ND. D-cycloserine facilitates extinction of cocaine self-administration in rats. Synapse 2011; 65:938-44. [PMID: 21360592 PMCID: PMC3188412 DOI: 10.1002/syn.20922] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Accepted: 01/13/2011] [Indexed: 11/09/2022]
Abstract
Previous research has indicated that D-cycloserine [DCS; a N-methyl-D-aspartate (NMDA) partial agonist] facilitates the extinction of conditioned fear as well as the extinction of cocaine conditioned place preference. Sprague Dawley rats were first trained to self-administer cocaine and then we compared their extinction behavior (lever pressing) following treatment with vehicle; 15 mg/kg DCS; or 30 mg/kg DCS. We showed that 30 mg/kg DCS, but not 15 mg/kg significantly accelerated extinction of cocaine self-administration behavior when compared with saline by almost half (4 days vs. 9 days). At 2 weeks when all animals had extinguished, there were no longer differences between the groups. The present findings support of the potential of NMDA partial agonists as prospectively valuable in facilitating the extinction of cocaine-seeking behavior. More specifically, we demonstrate that 30 mg/kg DCS was effective at significantly accelerating the extinction of cocaine self-administration behavior in rats. These results provide further support for the potential of DCS as a treatment strategy for addiction.
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Affiliation(s)
- Panayotis K Thanos
- Neuroimaging Lab, NIAAA Intramural Program, NIH, Bethesda, Maryland, USA.
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Vinci S, Ibba F, Longoni R, Spina L, Spiga S, Acquas E. Acetaldehyde elicits ERK phosphorylation in the rat nucleus accumbens and extended amygdala. Synapse 2011; 64:916-27. [PMID: 20506324 DOI: 10.1002/syn.20811] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Recent advances suggest that acetaldehyde mediates some of the neurobiological properties of ethanol. In a recent study, we have shown that ethanol elicits the phosphorylation of extracellular signal-regulated kinase (pERK) in the nucleus accumbens and extended amygdala, via a dopamine D(1) receptor-mediated mechanism. The aim of this study was to determine whether acetaldehyde and ethanol-derived acetaldehyde elicit the activation of ERK in the nucleus accumbens and extended amygdala. The effects of acetaldehyde (10 and 20 mg/kg) and ethanol (1 g/kg), administered to rats intragastrically, were assessed by pERK peroxidase immunohistochemistry. To establish the role of ethanol-derived acetaldehyde, the alcohol dehydrogenase inhibitor, 4-methylpyrazole (90 mg/kg), and the acetaldehyde-sequestering agent, D-penicillamine (50 mg/kg), were administered before ethanol. Acetaldehyde increased pERK immunoreactivity in the nucleus accumbens and extended amygdala. Inhibition of ethanol metabolism and sequestration of newly synthesized acetaldehyde completely prevented ERK activation by ethanol. In addition, to establish the role of D(1) receptors stimulation in acetaldehyde-elicited ERK phosphorylation, we studied the effect of the D(1) receptor antagonist, SCH 39166. Pretreatment with the D(1) receptor antagonist (50 μg/kg) fully prevented acetaldehyde-elicited ERK activation. Overall, these results indicate that ethanol activates ERK by means of its metabolic conversion into acetaldehyde and strengthen the view that acetaldehyde is a centrally acting compound with a pharmacological profile similar to ethanol.
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Affiliation(s)
- Stefania Vinci
- Department of Toxicology, University of Cagliari, 09124 Cagliari, Italy
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Longoni R, Spina L, Vinci S, Acquas E. The MEK inhibitor SL327 blocks acquisition but not expression of lithium-induced conditioned place aversion: a behavioral and immunohistochemical study. Psychopharmacology (Berl) 2011; 216:63-73. [PMID: 21312031 DOI: 10.1007/s00213-011-2192-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 01/17/2011] [Indexed: 11/27/2022]
Abstract
RATIONALE Recent evidence involves extracellular signal-regulated kinase (ERK) in positive motivational properties of drugs as determined by conditioned place preference but, to date, its role in conditioned place aversion (CPA) still awaits to be fully characterized. OBJECTIVES The aim of this study was to assess whether activated ERK (pERK) plays a role in the acquisition and/or expression of lithium-induced CPA. METHODS C57BL/6J mice were subjected to lithium (150 mg/kg)-induced CPA. The role of pERK was determined by administering the mitogen-activating extracellular kinase inhibitor, SL327, (a) 25 and 50 mg/kg, before each exposure to the lithium-associated compartment (acquisition), and (b) 25, 50, and 100 mg/kg, before post-conditioning test (expression). To assess whether ERK is activated by acute lithium and, in distinct experiments, during CPA expression, mice were sacrificed, 30 min after lithium, and immediately after post-conditioning test, respectively, for pERK immunohistochemistry. RESULTS Lithium increased pERK-positive neurons in bed nucleus of stria termialis, in central and basolateral amygdala and elicited significant CPA. SL327 (50 mg/kg) significantly prevented its acquisition. In addition, the post-conditioning test of lithium-conditioned mice determined a significant increase of pERK-positive neurons in the dorsal striatum and SL327 (50 mg/kg), administered before post-conditioning test, while failing at the doses of 25, 50, and 100 mg/kg, to affect lithium-induced CPA expression, completely prevented it. CONCLUSIONS These results indicate that pERK is critical for acquisition, but not expression, of lithium-induced CPA and that its activation in the dorsal striatum, during expression, is not critical for retrieval of the aversive memory.
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Affiliation(s)
- Rosanna Longoni
- Department of Toxicology, University of Cagliari, Via Ospedale, 72, 09124, Cagliari, Italy
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Airavaara M, Pickens CL, Stern AL, Wihbey KA, Harvey BK, Bossert JM, Liu QR, Hoffer BJ, Shaham Y. Endogenous GDNF in ventral tegmental area and nucleus accumbens does not play a role in the incubation of heroin craving. Addict Biol 2011; 16:261-72. [PMID: 21182575 DOI: 10.1111/j.1369-1600.2010.00281.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) activity in ventral tegmental area (VTA) mediates the time-dependent increases in cue-induced cocaine-seeking after withdrawal (incubation of cocaine craving). Here, we studied the generality of these findings to incubation of heroin craving. Rats were trained to self-administer heroin for 10 days (6 hours/day; 0.075 mg/kg/infusion; infusions were paired with a tone-light cue) and tested for cue-induced heroin-seeking in extinction tests after 1, 11 or 30 withdrawal days. Cue-induced heroin seeking was higher after 11 or 30 days than after 1 day (incubation of heroin craving), and the time-dependent increases in extinction responding were associated with time-dependent changes in GDNF mRNA expression in VTA and nucleus accumbens. Additionally, acute accumbens (but not VTA) GDNF injections (12.5 µg/side) administered 1-3 hours after the last heroin self-administration training session enhanced the time-dependent increases in extinction responding after withdrawal. However, the time-dependent increases in extinction responding after withdrawal were not associated with changes in GDNF protein expression in VTA and accumbens. Additionally, interfering with endogenous GDNF function by chronic delivery of anti-GDNF monoclonal neutralizing antibodies (600 ng/side/day) into VTA or accumbens had no effect on the time-dependent increases in extinction responding. In summary, heroin self-administration and withdrawal regulate VTA and accumbens GDNF mRNA expression in a time-dependent manner, and exogenous GDNF administration into accumbens but not VTA potentiates cue-induced heroin seeking. However, based on the GDNF protein expression and the anti-GDNF monoclonal neutralizing antibodies manipulation data, we conclude that neither accumbens nor VTA endogenous GDNF mediates the incubation of heroin craving.
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Affiliation(s)
- Mikko Airavaara
- Intramural Research Program and National Institute on Drug Abuse, NIH, Baltimore, MD 21224, USA
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35
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Neugebauer NM, Henehan RM, Hales CA, Picciotto MR. Mice lacking the galanin gene show decreased sensitivity to nicotine conditioned place preference. Pharmacol Biochem Behav 2010; 98:87-93. [PMID: 21172385 DOI: 10.1016/j.pbb.2010.12.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 12/06/2010] [Accepted: 12/11/2010] [Indexed: 12/20/2022]
Abstract
Previous work has indicated that the neuropeptide galanin decreases sensitivity to the rewarding effects of morphine and cocaine, but increases alcohol drinking. The aim of the current study was to examine the role of galanin signaling in nicotine reward by testing the effects of nicotine in mice lacking galanin peptide (GAL-/-) as compared to wild-type (GAL+/+) controls. Using an unbiased, three-chamber conditioned place preference (CPP) paradigm the dose-response function for nicotine CPP was tested in GAL-/- and GAL+/+ mice. Since activation of extracellular signal-related kinase (ERK2) is involved in the rewarding effects of several classes of drugs of abuse, we then measured the level of ERK2 phosphorylation in the nucleus accumbens shell (NACsh) and core (NACco) of GAL-/- and GAL+/+ mice following re-exposure to the CPP chamber previously paired with nicotine as a marker of mesolimbic system activation. Finally, we examined whether acute nicotine administration affects ERK2 activity in GAL-/- and GAL+/+ mice. GAL-/- mice required a higher dose of nicotine to induce a significant CPP compared to GAL+/+ mice. In the conditioning groups showing significant expression of nicotine CPP, only GAL+/+ mice showed ERK2 activation in the NACsh. This suggests that the nicotine CPP observed in GAL+/+ mice resulted in differential recruitment of ERK signaling in the NACsh compared to GAL-/- mice. In addition, no activation of ERK2 was observed following acute nicotine administration in either genotype. These data, along with prior results, suggest that galanin alters sensitivity to drugs of abuse differentially, with morphine, cocaine and amphetamine place preference suppressed, and nicotine and alcohol preference increased, by galanin signaling.
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Affiliation(s)
- Nichole M Neugebauer
- Division of Molecular Psychiatry, Abraham Ribicoff Research Facilities, Connecticut Mental Health Center, Yale University School of Medicine, New Haven, CT 06508, United States
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Basolateral amygdala cdk5 activity mediates consolidation and reconsolidation of memories for cocaine cues. J Neurosci 2010; 30:10351-9. [PMID: 20685978 DOI: 10.1523/jneurosci.2112-10.2010] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Cocaine use and relapse involves learned associations between cocaine-associated environmental contexts and discrete stimuli and cocaine effects. Initially, these contextual and discrete cues undergo memory consolidation after being paired with cocaine exposure. During abstinence, cocaine cue memories can undergo memory reconsolidation after cue exposure without the drug. We used a conditioned place preference (CPP) procedure in rats to study the role of neuronal protein kinase cyclin-dependent kinase 5 (Cdk5) in consolidation and reconsolidation of cocaine cue memories. We found that the expression of cocaine CPP in drug-free tests 1 d after CPP training (four pairings of 10 mg/kg cocaine with one context and four pairings of saline with a different context) increased Cdk5 activity, and levels of the Cdk5 activator p35 in basolateral but not central amygdala. We also found that basolateral (but not central) amygdala injections of the Cdk5 inhibitor beta-butyrolactone (100 ng/side) immediately (but not 6 h) after cocaine-context pairings during training prevented subsequent cocaine CPP expression. After training, acute basolateral (but not central) amygdala beta-butyrolactone injections immediately before testing prevented the expression of cocaine CPP; this effect was also observed on a second test performed 1 d later, suggesting an effect on reconsolidation of cocaine cue memories. In support, basolateral beta-butyrolactone injections, given immediately (but not 6 h) after a single exposure to the cocaine-paired context, prevented cocaine CPP expression 1 and 14 d after the injections. Results indicate that basolateral amygdala Cdk5 activity is critical for consolidation and reconsolidation of the memories of cocaine-associated environmental cues.
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Spina L, Longoni R, Vinci S, Ibba F, Peana AT, Muggironi G, Spiga S, Acquas E. Role of dopamine D1 receptors and extracellular signal regulated kinase in the motivational properties of acetaldehyde as assessed by place preference conditioning. Alcohol Clin Exp Res 2010; 34:607-16. [PMID: 20102564 DOI: 10.1111/j.1530-0277.2009.01129.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND The role of dopamine D1 receptors and Extracellular signal Regulated Kinase (ERK) in the motivational properties of drugs can be studied by place-conditioning. Recent advances have shown that the motivational properties of ethanol, determined by place-conditioning, are mediated by its metabolic conversion into acetaldehyde. To date, the role of D1 receptors and ERK activation in acetaldehyde-elicited place preference has not been determined. The aim of this study was to assess the role of D1 receptors blockade and MEK inhibition in the acquisition of acetaldehyde-elicited conditioned place preference. METHODS Male Sprague-Dawley rats were subjected to repeated pairings with 1 compartment of the conditioning apparatus immediately following acetaldehyde (20 mg/kg i.g.) or ethanol (1 g/kg i.g.) administration. The D1 receptor antagonist, SCH 39166 (50 microg/kg s.c.), was administered 10 minutes before acetaldehyde or ethanol administration. In order to study the role of activated ERK in the acetaldehyde-elicited place preference, rats were administered the MEK inhibitor, PD98059 (1, 30, and 90 microg i.c.v.), 10 or 30 minutes before acetaldehyde. To verify the specificity of these effects, we also studied whether PD98059 pretreatment could affect morphine (1 mg/kg s.c.)-elicited place preference. RESULTS Both acetaldehyde and ethanol elicited significant place preferences and these were prevented by pretreatment with SCH 39166. In addition, pretreatment with PD98059, dose (30 and 90 but not 1 microg i.c.v.) and time (10 but not 30 minutes before) dependently, prevented the acquisition of acetaldehyde- and significantly reduced the acquisition of morphine-elicited conditioned place preference. CONCLUSIONS These results confirm that acetaldehyde and ethanol elicit conditioned place preference and demonstrate that D1 receptors are critically involved in these effects. Furthermore, the finding that PD98059 prevents the acquisition of acetaldehyde-elicited conditioned place preference highlights the importance of the D1 receptor-ERK pathway in its motivational effects.
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Affiliation(s)
- Liliana Spina
- Department of Toxicology, University of Cagliari, Cagliari, Italy
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Seip KM, Morrell JI. Transient inactivation of the ventral tegmental area selectively disrupts the expression of conditioned place preference for pup- but not cocaine-paired contexts. Behav Neurosci 2009; 123:1325-38. [PMID: 20001116 PMCID: PMC2828762 DOI: 10.1037/a0017666] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The ventral tegmental area (VTA) plays a critical role in motivated behavior. However, it remains unclear whether intact VTA function is necessary for motivated behavior to seek contexts repeatedly paired with natural stimuli and/or pharmacological stimuli. In the present study, conditioned place preference (CPP) was induced with highly salient natural or drug stimuli attributed with strong incentive-motivational value in each of 2 female models: Postpartum females were conditioned to associate one unique context in the CPP apparatus with young offspring (pups) and a second context with a neutral stimulus, and virgin females were conditioned to associate unique contexts with cocaine (5 mg/kg ip) and saline injections. Immediately before CPP testing, each female received a microinfusion of bupivacaine bilaterally into the VTA to transiently inactivate the region; subjects were also tested after saline microinfusion into the VTA. Postpartum females' preference for the pup-paired context was abolished by VTA inactivation but was restored to high control levels after saline microinfusion. In separate tests, VTA inactivation also reduced motivated pup licking and pup retrieval in postpartum females, suggesting that intact VTA function is required for the expression of both pup CPP and motivated pup-directed behaviors. Cocaine CPP remained unaffected by VTA inactivation. Locomotion was not affected by VTA microinfusions but was severely impaired by bupivacaine microinfusions into the substantia nigra. We concluded that the VTA is differentially involved in the expression of conditioned preference for contexts paired with pups, a salient natural stimulus, and contexts paired with cocaine.
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Affiliation(s)
- Katharine M Seip
- Center for Molecular & Behavioral Neuroscience, Rutgers-The State University of New Jersey, Newark, NJ 07102, USA.
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39
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Protein kinases A and C in post-mortem prefrontal cortex from persons with major depression and normal controls. Int J Neuropsychopharmacol 2009; 12:1223-32. [PMID: 19573263 PMCID: PMC3832297 DOI: 10.1017/s1461145709000285] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Major depression (MDD) is a common and potentially life-threatening condition. Widespread neurobiological abnormalities suggest abnormalities in fundamental cellular mechanisms as possible physiological mediators. Cyclic AMP-dependent protein kinase [also known as protein kinase A (PKA)] and protein kinase C (PKC) are important components of intracellular signal transduction cascades that are linked to G-coupled receptors. Previous research using both human peripheral and post-mortem brain tissue specimens suggests that a subset of depressed patients exhibit reduced PKA and PKC activity, which has been associated with reduced levels of specific protein isoforms. Prior research also suggests that specific clinical phenotypes, particularly melancholia and suicide, may be particularly associated with low activity. This study examined PKA and PKC protein levels in human post-mortem brain tissue samples from persons with MDD (n=20) and age- and sex-matched controls (n=20). Specific PKA subunits and PKC isoforms were assessed using Western blot analysis in post-mortem samples from Brodmann area 10, which has been implicated in reinforcement and reward mechanisms. The MDD sample exhibited significantly lower protein expression of PKA regulatory Ialpha (RIalpha), PKA catalytic alpha (Calpha) and Cbeta, PKCbeta1, and PKCepsilon relative to controls. The melancholic subgroup showed low PKA RIalpha and PKA Cbeta, while the portion of the MDD sample who died by suicide had low PKA RIalpha and PKA Calpha. These data continue to support the significance of abnormalities of these two key kinases, and suggest linkages between molecular endophenotypes and specific clinical phenotypes.
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Nair SG, Adams-Deutsch T, Epstein DH, Shaham Y. The neuropharmacology of relapse to food seeking: methodology, main findings, and comparison with relapse to drug seeking. Prog Neurobiol 2009; 89:18-45. [PMID: 19497349 PMCID: PMC2745723 DOI: 10.1016/j.pneurobio.2009.05.003] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2009] [Revised: 04/09/2009] [Accepted: 05/26/2009] [Indexed: 12/15/2022]
Abstract
Relapse to old, unhealthy eating habits is a major problem in human dietary treatments. The mechanisms underlying this relapse are unknown. Surprisingly, until recently this clinical problem has not been systematically studied in animal models. Here, we review results from recent studies in which a reinstatement model (commonly used to study relapse to abused drugs) was employed to characterize the effect of pharmacological agents on relapse to food seeking induced by either food priming (non-contingent exposure to small amounts of food), cues previously associated with food, or injections of the pharmacological stressor yohimbine. We also address methodological issues related to the use of the reinstatement model to study relapse to food seeking, similarities and differences in mechanisms underlying reinstatement of food seeking versus drug seeking, and the degree to which the reinstatement procedure provides a suitable model for studying relapse in humans. We conclude by discussing implications for medication development and future research. We offer three tentative conclusions: (1)The neuronal mechanisms of food-priming- and cue-induced reinstatement are likely different from those of reinstatement induced by the pharmacological stressor yohimbine. (2)The neuronal mechanisms of reinstatement of food seeking are possibly different from those of ongoing food-reinforced operant responding. (3)The neuronal mechanisms underlying reinstatement of food seeking overlap to some degree with those of reinstatement of drug seeking.
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Affiliation(s)
- Sunila G. Nair
- Behavioral Neuroscience Branch, NIDA/IRP, 251 Bayview Boulevard, Baltimore, MD, 21224
| | - Tristan Adams-Deutsch
- Behavioral Neuroscience Branch, NIDA/IRP, 251 Bayview Boulevard, Baltimore, MD, 21224
| | - David H. Epstein
- Clinical Pharmacology and Therapeutics Research Branch, NIDA/IRP, 251 Bayview Boulevard, Baltimore, MD, 21224
| | - Yavin Shaham
- Behavioral Neuroscience Branch, NIDA/IRP, 251 Bayview Boulevard, Baltimore, MD, 21224
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41
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Dopaminergic mechanism of reward-related incentive learning: focus on the dopamine D(3) receptor. Neurotox Res 2009; 14:57-70. [PMID: 18790725 DOI: 10.1007/bf03033575] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Dopamine D(3) receptors (Drd3) have been implicated in the control of responding by drug-related conditioned incentive stimuli. We review recent studies of the effects of Drd3 antagonists or partial agonists on the control of self-administration of intravenous (IV) cocaine, IV morphine and oral ethanol on reward-rich and lean schedules, in reinstatement tests, on second-order schedules and on the acquisition and expression of conditioned place preference (CPP) and conditioned motor activity. For comparison, related studies where conditioned stimuli are based on nutritional reward also are considered. When self-administration depends more heavily on conditioned cues for its maintenance, for example on second-order schedules or lean ratio schedules, Drd3 antagonists or partial agonists reduce responding. Although data are limited, similar effects may be seen for responding for cues based on drugs or nutritional rewards. Drd3 agents also block the ability of conditioned cues to reinstate responding for cocaine or food. Published results suggest that Drd3 plays a more important role in the expression than in the acquisition of a CPP or conditioned motor activity. The mechanism mediating the role of Drd3 in the control of responding by conditioned incentive stimuli remains unknown but it has been found that Drd3 receptors increase in number in the nucleus accumbens during conditioning. Perhaps Drd3 participates in the molecular mechanisms underlying the role of dopamine and of dopamine receptor subtypes in reward-related incentive learning.
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Kristiansen LV, Bannon MJ, Meador-Woodruff JH. Expression of transcripts for myelin related genes in postmortem brain from cocaine abusers. Neurochem Res 2009; 34:46-54. [PMID: 18357522 PMCID: PMC2615829 DOI: 10.1007/s11064-008-9655-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Accepted: 03/07/2008] [Indexed: 11/30/2022]
Abstract
Chronic abuse of cocaine is known to cause neuroadaptive changes in the nucleus accumbens (NAc) and ventral tegmental area (VTA). In addition, altered expression of the myelin-related genes MBP, MOBP, PLP1 as well as of MAL2 in NAc was recently reported by gene array analysis in brains from cocaine abusers. In the present study we used in situ hybridization to quantify transcript expression of these four genes, as well as for the myelin-related transcripts encoding quaking, EDG2, claudin-11, transferrin, CNP, and MAG in caudate, putamen, internal capsule, and NAc in postmortem brain from cocaine abusers and matched comparison subjects. Most transcripts were not different between these groups in these striatal regions, and contrary to previous reports, we did not detect any changes in the NAc. However, expression of the transcript encoding PLP1 was significantly decreased in ventral and dorsal regions of the caudate, putamen, and in the internal capsule. Additionally, expression of claudin-11 and transferrin was decreased in the caudate and internal capsule, respectively. PLP1 is expressed at very high levels in oligodendrocytes and is essential in maintaining stability of myelin sheets. Based on these findings, altered expression of PLP1 in most areas of the striatum suggests that widespread changes to the myelin structure could be associated with the adaptive changes following chronic cocaine abuse.
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Affiliation(s)
- Lars V Kristiansen
- Department of Psychiatry & Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL, USA.
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Acute and chronic dopamine receptor stimulation modulates AMPA receptor trafficking in nucleus accumbens neurons cocultured with prefrontal cortex neurons. J Neurosci 2008; 28:4216-30. [PMID: 18417701 DOI: 10.1523/jneurosci.0258-08.2008] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Postsynaptic interactions between dopamine (DA) and glutamate receptors in the nucleus accumbens (NAc) are critical for addiction. To determine the effect of acute and repeated DA receptor stimulation on AMPA receptor (AMPAR) synaptic targeting in medium spiny NAc neurons, we developed a model system consisting of rat NAc neurons cocultured with prefrontal cortex neurons from enhanced green fluorescent protein-expressing mice. Cortical neurons restore excitatory input onto NAc neurons but are distinguishable based on fluorescence. First, we showed that brief D1-like agonist exposure increased AMPAR insertion onto extrasynaptic regions of NAc neuronal processes through a mechanism requiring protein kinase A. This facilitated the Ca2+/calmodulin dependent protein kinase II (CaMKII)-dependent synaptic incorporation of AMPARs in response to subsequent NMDA receptor (NMDAR) stimulation. Through this mechanism, DA may promote reward- and drug-related plasticity in the NAc. Then, to model effects of repeated in vivo cocaine exposure, we treated cocultures with DA (1 microm, 30 min) on days 7, 9, and 11 in culture. On day 15, NAc neurons exhibited increased synaptic AMPAR levels. This was associated with CaMKII activation and was blocked by the CaMKII inhibitor KN-93 (N-[2-[N-(4-chlorocinnamyl)-N-methylaminomethyl]phenyl]-N-(2-hydroxyethyl)-4-methoxybenzenesulfonamide phosphate salt). Furthermore, D1-like agonist exposure on day 15 no longer increased AMPAR surface expression. This refractoriness was associated with decreased D1 receptor surface expression. NMDAR surface expression was not altered by acute or repeated DA receptor stimulation. These results suggest that (1) after repeated DA treatment, NAc neurons are more responsive to glutamate inputs but D(1)-like receptor regulation of plasticity is impaired, and (2) NAc/prefrontal cortex cocultures are useful for studying dopamine-induced neuroadaptations.
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Honsberger MJM, Leri F. Fos expression in mesocorticolimbic areas during heroin place conditioning. Neuroreport 2008; 19:63-7. [PMID: 18281894 DOI: 10.1097/wnr.0b013e3282f31d82] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We studied Fos immunoreactivity within targets of the mesocorticolimbic dopamine systems at different stages of acquisition of heroin place conditioning. Fos was quantified in groups of rats after one or four exposures to 0.3-mg/kg heroin only, or to the conditioning compartment only, or to both heroin and the conditioning compartment, or to neither stimuli. Increases in Fos were found primarily after the first exposure. Further, the medial prefrontal cortex was the only region displaying higher Fos expression in the group exposed to both heroin and conditioning compartment. It is concluded that the medial prefrontal cortex may be the neural site whereby neural representations of novel stimuli with motivational value are associated during associative learning.
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45
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Weiler JA, Bellebaum C, Daum I. Aging affects acquisition and reversal of reward-based associative learning. Learn Mem 2008; 15:190-7. [PMID: 18353994 DOI: 10.1101/lm.890408] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Reward-based associative learning is mediated by a distributed network of brain regions that are dependent on the dopaminergic system. Age-related changes in key regions of this system, the striatum and the prefrontal cortex, may adversely affect the ability to use reward information for the guidance of behavior. The present study investigated the effects of healthy aging on different components of reward learning, such as acquisition, reversal, effects of reward magnitude, and transfer of learning. A group of 30 young (mean age = 24.2 yr) and a group of 30 older subjects (mean age = 64.1 yr) completed two probabilistic reward-based stimulus association learning tasks. Older subjects showed poorer overall acquisition and impaired reversal learning, as well as deficits in transfer learning. When only those subjects who showed evidence of significant learning were considered, younger subjects showed equivalently fast learning irrespective of reward magnitude, while learning curves in older subjects were steeper for high compared to low reward magnitudes. Acquired equivalence learning, which requires generalization across stimuli and transfer of learned contingencies to new stimuli, was mildly impaired in older subjects.
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Affiliation(s)
- Julia A Weiler
- Institute of Cognitive Neuroscience, Department of Neuropsychology, Ruhr-University of Bochum, 44780 Bochum, Germany.
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46
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Opposing regulation of pair bond formation by cAMP signaling within the nucleus accumbens shell. J Neurosci 2008; 27:13352-6. [PMID: 18045929 DOI: 10.1523/jneurosci.3216-07.2007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The formation of monogamous pair bonds, by prairie voles, is facilitated by activation of dopamine (DA) D2-like, but not D1-like, receptors within the nucleus accumbens (NAcc) shell. Because DA exerts opposing regulation of cAMP production depending on the subtype of receptor activated, we tested the hypothesis that DA regulation of pair bond formation is mediated via the cAMP signaling cascade. Consistent with activation of D2-like receptors, decreasing cAMP signaling, by blocking cAMP binding sites on protein kinase A (PKA), facilitated partner preference formation. Conversely, increasing cAMP signaling, by preventing the activation of inhibitory G-proteins, activating stimulatory G-proteins, or stimulating PKA prevented the formation of mating-induced partner preferences. These manipulations were effective in the shell, but not the core, of the NAcc. Together, these data demonstrate opposing regulation over pair bond formation by cAMP signaling within the NAcc shell.
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47
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Zhai HF, Zhang ZY, Zhao M, Qiu Y, Ghitza UE, Lu L. Conditioned drug reward enhances subsequent spatial learning and memory in rats. Psychopharmacology (Berl) 2007; 195:193-201. [PMID: 17661018 DOI: 10.1007/s00213-007-0893-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2006] [Accepted: 07/05/2007] [Indexed: 11/27/2022]
Abstract
RATIONALE Chronic exposure to drugs of abuse alters neural processes that normally promote learning and memory. A context that is repeatedly paired with reinforcing drugs will acquire secondary reinforcing properties (conditioned reward). However, the effects of conditioned reward on spatial learning are unknown. OBJECTIVE Using the conditioned place preference procedure and Morris water maze task, we examined the role of conditioned reward or aversion in spatial learning. MATERIALS AND METHODS Groups of rats acquired morphine (10 mg/kg), cocaine (10 mg/kg), or oral sucrose (15%) conditioned place preference (CPP). Another group of morphine-dependent rats acquired conditioned place aversion (CPA) to a context paired with precipitated opiate withdrawal induced by naloxone injections (1 mg/kg). To examine the role of conditioned reward or aversion in spatial learning, rats were then exposed to the previously morphine-, cocaine-, sucrose- or naloxone-paired context for 10 min before training of spatial learning in the Morris water maze. RESULTS Exposure to the morphine- or cocaine-paired but not the sucrose- or the naloxone-paired context decreased the latency to find the platform in the Morris water maze test. CONCLUSIONS Our results provide the first evidence that conditioned drug reward promotes spatial learning. We speculate that this enhancement of spatial learning by the drug-paired context may promote contextual-cue-induced relapse to drug taking by facilitating exploratory drug-seeking behaviors.
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Affiliation(s)
- Hai-feng Zhai
- Department of Neuropharmacology, National Institute on Drug Dependence, Peking University, 38, Xue Yuan Road, HaiDian District, Beijing 100083, China
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48
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Phillmore LS. Discrimination: from behaviour to brain. Behav Processes 2007; 77:285-97. [PMID: 18096329 DOI: 10.1016/j.beproc.2007.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Revised: 11/11/2007] [Accepted: 11/12/2007] [Indexed: 12/12/2022]
Abstract
Discrimination is a skill needed by many organisms for survival: decisions about food, shelter, and mate selection all require the ability to distinguish among stimuli. This article reviews the how and why of discrimination and how researchers may exploit this natural skill in the laboratory to learn more about what features of stimuli animals use to discriminate. The paper then discusses the possible neurophysiological basis of discrimination and proposes a model, based on one of stimulus-association put forth by Beninger and Gerdjikov (2004) [Beninger, R.J., Gerdjikov, T.V., 2004. The role of signaling molecules in reward-related incentive learning. Neurotox. Res., 6, 91-104], to account for the role of dopamine in how an animal learns to discriminate rewarded from non-rewarded stimuli.
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49
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Porr B, Wörgötter F. Learning with "relevance": using a third factor to stabilize Hebbian learning. Neural Comput 2007; 19:2694-719. [PMID: 17716008 DOI: 10.1162/neco.2007.19.10.2694] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
It is a well-known fact that Hebbian learning is inherently unstable because of its self-amplifying terms: the more a synapse grows, the stronger the postsynaptic activity, and therefore the faster the synaptic growth. This unwanted weight growth is driven by the autocorrelation term of Hebbian learning where the same synapse drives its own growth. On the other hand, the cross-correlation term performs actual learning where different inputs are correlated with each other. Consequently, we would like to minimize the autocorrelation and maximize the cross-correlation. Here we show that we can achieve this with a third factor that switches on learning when the autocorrelation is minimal or zero and the cross-correlation is maximal. The biological counterpart of such a third factor is a neuromodulator that switches on learning at a certain moment in time. We show in a behavioral experiment that our three-factor learning clearly outperforms classical Hebbian learning.
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Affiliation(s)
- Bernd Porr
- Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow, GT12 8LT, Scotland.
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50
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Tzschentke TM. Measuring reward with the conditioned place preference (CPP) paradigm: update of the last decade. Addict Biol 2007; 12:227-462. [PMID: 17678505 DOI: 10.1111/j.1369-1600.2007.00070.x] [Citation(s) in RCA: 1006] [Impact Index Per Article: 59.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Conditioned place preference (CPP) continues to be one of the most popular models to study the motivational effects of drugs and non-drug treatments in experimental animals. This is obvious from a steady year-to-year increase in the number of publications reporting the use this model. Since the compilation of the preceding review in 1998, more than 1000 new studies using place conditioning have been published, and the aim of the present review is to provide an overview of these recent publications. There are a number of trends and developments that are obvious in the literature of the last decade. First, as more and more knockout and transgenic animals become available, place conditioning is increasingly used to assess the motivational effects of drugs or non-drug rewards in genetically modified animals. Second, there is a still small but growing literature on the use of place conditioning to study the motivational aspects of pain, a field of pre-clinical research that has so far received little attention, because of the lack of appropriate animal models. Third, place conditioning continues to be widely used to study tolerance and sensitization to the rewarding effects of drugs induced by pre-treatment regimens. Fourth, extinction/reinstatement procedures in place conditioning are becoming increasingly popular. This interesting approach is thought to model certain aspects of relapse to addictive behavior and has previously almost exclusively been studied in drug self-administration paradigms. It has now also become established in the place conditioning literature and provides an additional and technically easy approach to this important phenomenon. The enormous number of studies to be covered in this review prevented in-depth discussion of many methodological, pharmacological or neurobiological aspects; to a large extent, the presentation of data had to be limited to a short and condensed summary of the most relevant findings.
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Affiliation(s)
- Thomas M Tzschentke
- Grünenthal GmbH, Preclinical Research and Development, Department of Pharmacology, Aachen, Germany.
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