1
|
Neasta J, Darcq E, Jeanblanc J, Carnicella S, Ben Hamida S. GPCR and Alcohol-Related Behaviors in Genetically Modified Mice. Neurotherapeutics 2020; 17:17-42. [PMID: 31919661 PMCID: PMC7007453 DOI: 10.1007/s13311-019-00828-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
G protein-coupled receptors (GPCRs) constitute the largest class of cell surface signaling receptors and regulate major neurobiological processes. Accordingly, GPCRs represent primary targets for the treatment of brain disorders. Several human genetic polymorphisms affecting GPCRs have been associated to different components of alcohol use disorder (AUD). Moreover, GPCRs have been reported to contribute to several features of alcohol-related behaviors in animal models. Besides traditional pharmacological tools, genetic-based approaches mostly aimed at deleting GPCR genes provided substantial information on how key GPCRs drive alcohol-related behaviors. In this review, we summarize the alcohol phenotypes that ensue from genetic manipulation, in particular gene deletion, of key GPCRs in rodents. We focused on GPCRs that belong to fundamental neuronal systems that have been shown as potential targets for the development of AUD treatment. Data are reviewed with particular emphasis on alcohol reward, seeking, and consumption which are behaviors that capture essential aspects of AUD. Literature survey indicates that in most cases, there is still a gap in defining the intracellular transducers and the functional crosstalk of GPCRs as well as the neuronal populations in which their signaling regulates alcohol actions. Further, the implication of only a few orphan GPCRs has been so far investigated in animal models. Combining advanced pharmacological technologies with more specific genetically modified animals and behavioral preclinical models is likely necessary to deepen our understanding in how GPCR signaling contributes to AUD and for drug discovery.
Collapse
Affiliation(s)
- Jérémie Neasta
- Laboratoire de Pharmacologie, Faculté de Pharmacie, University of Montpellier, 34093, Montpellier, France
| | - Emmanuel Darcq
- Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 Boulevard LaSalle, Montreal, Quebec, H4H 1R3, Canada
| | - Jérôme Jeanblanc
- Research Group on Alcohol and Pharmacodependences-INSERM U1247, University of Picardie Jules Verne, 80025, Amiens, France
| | - Sebastien Carnicella
- INSERM U1216, Grenoble Institut des Neurosciences (GIN), University of Grenoble Alpes, 38000, Grenoble, France
| | - Sami Ben Hamida
- Douglas Hospital Research Center, Department of Psychiatry, McGill University, 6875 Boulevard LaSalle, Montreal, Quebec, H4H 1R3, Canada.
| |
Collapse
|
2
|
Ethanol-induced changes in synaptic amino acid neurotransmitter levels in the nucleus accumbens of differentially sensitized mice. Psychopharmacology (Berl) 2019; 236:3541-3556. [PMID: 31302721 DOI: 10.1007/s00213-019-05324-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 07/02/2019] [Indexed: 01/21/2023]
Abstract
RATIONALE Ethanol-induced behavioural sensitization (EBS) does not occur uniformly in mice exposed to the sensitization paradigm. This suggests innate differential responses to ethanol (EtOH) in the reward circuitry of individual animals. OBJECTIVES To better characterize the adaptive differences between low-sensitized (LS) and high-sensitized (HS) mice, we examined excitatory amino acid (EAA) and inhibitory amino acid (IAA) neurotransmitter levels in the nucleus accumbens (NAc) during EBS expression. METHODS Male DBA/2J mice received five ethanol (EtOH) (2.2 g/kg) or saline injections, and locomotor activity (LMA) was assessed during EBS induction. EtOH mice were classified as LS or HS on the basis of final LMA scores. Following an EtOH challenge (1.8 g/kg) 2 weeks later, LMA was re-evaluated and in vivo microdialysis samples were collected from the NAc. RESULTS Most differences in amino acid levels were observed within the first 20 min after EtOH challenge. LS mice exhibited similar glutamate levels compared with acutely treated (previously EtOH naïve) mice, and generally increased levels of the IAAs GABA, glycine, and taurine. By contrast, HS mice exhibited increased glutamate and attenuated levels of GABA, glycine, and taurine. CONCLUSION These data suggest that the profile of amino acid neurotransmitters in the NAc of LS and HS mice significantly differs. Elucidating these adaptive differences contributes to our understanding of factors that confer susceptibility/resilience to alcohol use disorder.
Collapse
|
3
|
Nona CN, Hendershot CS, Lê AD. Behavioural sensitization to alcohol: Bridging the gap between preclinical research and human models. Pharmacol Biochem Behav 2018; 173:15-26. [DOI: 10.1016/j.pbb.2018.08.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 07/31/2018] [Accepted: 08/07/2018] [Indexed: 12/28/2022]
|
4
|
Nona CN, Nobrega JN. A role for nucleus accumbens glutamate in the expression but not the induction of behavioural sensitization to ethanol. Behav Brain Res 2017; 336:269-281. [PMID: 28919158 DOI: 10.1016/j.bbr.2017.09.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 08/23/2017] [Accepted: 09/13/2017] [Indexed: 12/27/2022]
Abstract
Mechanisms underlying differential sensitivity to behavioural sensitization to ethanol (EtOH) remain poorly understood, although accumulating evidence suggests a role for glutamatergic processes in the ventral striatum. Efforts to address this issue can benefit from the well-documented fact that in any given cohort, some of the mice (High sensitized; HS) show robust sensitization, while others (Low sensitized; LS) show little, if any, sensitization. Here, we examined whether this variability might be differentially associated with nucleus accumbens (NAc) glutamate processes. Male DBA mice received 5 EtOH (2.2g/kg) or saline injections twice a week and were challenged with EtOH (1.8g/kg) 2 weeks after injection 5. When an EtOH challenge was administered 2 weeks following the induction of sensitization, HS, but not LS, mice showed a robust increase in glutamate levels (67%, P<0.01) as measured by in vivo microdialysis. In a separate cohort, the mGlu2/3 agonist LY354740 (10mg/kg), given prior to the EtOH challenge, abolished the expression of sensitization. To ascertain whether enhanced release could also be observed during the induction of sensitization, glutamate levels were measured after the 1st and 5th EtOH injection and were found to be unchanged in HS mice, although briefly elevated in LS mice at injection 5. To further assess possible glutamate involvement during the induction of sensitization, sensitizing EtOH injections were co-administered with NMDAR antagonists. At the doses used, MK-801 (0.25mg/kg) and CGS 19755 (10mg/kg) blocked the expression of sensitization, but did not significantly interfere with the development of EtOH sensitization. Within the limitations of the present design, the results suggest an important role for EtOH-induced glutamate release in the NAc when sensitization is well established, but not necessarily during the development of sensitization.
Collapse
Affiliation(s)
- Christina N Nona
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada; Behavioural Neurobiology Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada.
| | - José N Nobrega
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada; Behavioural Neurobiology Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, ON, Canada; Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada; Departments of Psychiatry and Psychology, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
5
|
Aranda GP, Hinojos SJ, Sabandal PR, Evans PD, Han KA. Behavioral Sensitization to the Disinhibition Effect of Ethanol Requires the Dopamine/Ecdysone Receptor in Drosophila. Front Syst Neurosci 2017; 11:56. [PMID: 28824387 PMCID: PMC5539124 DOI: 10.3389/fnsys.2017.00056] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 07/17/2017] [Indexed: 12/15/2022] Open
Abstract
Male flies under the influence of ethanol display disinhibited courtship, which is augmented with repeated ethanol exposures. We have previously shown that dopamine is important for this type of ethanol-induced behavioral sensitization but the underlying mechanism is unknown. Here we report that DopEcR, an insect G-protein coupled receptor that binds to dopamine and steroid hormone ecdysone, is a major receptor mediating courtship sensitization. Upon daily ethanol administration, dumb and damb mutant males defective in D1 (dDA1/DopR1) and D5 (DAMB/DopR2) dopamine receptors, respectively, showed normal courtship sensitization; however, the DopEcR-deficient der males exhibited greatly diminished sensitization. der mutant males nevertheless developed normal tolerance to the sedative effect of ethanol, indicating a selective function of DopEcR in chronic ethanol-associated behavioral plasticity. DopEcR plays a physiological role in behavioral sensitization since courtship sensitization in der males was reinstated when DopEcR expression was induced during adulthood but not during development. When examined for the DopEcR’s functional site, the der mutant’s sensitization phenotype was fully rescued by restored DopEcR expression in the mushroom body (MB) αβ and γ neurons. Consistently, we observed DopEcR immunoreactivity in the MB calyx and lobes in the wild-type Canton-S brain, which was barely detectable in the der brain. Behavioral sensitization to the locomotor-stimulant effect has been serving as a model for ethanol abuse and addiction. This is the first report elucidating the mechanism underlying behavioral sensitization to another stimulant effect of ethanol.
Collapse
Affiliation(s)
- Gissel P Aranda
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
| | - Samantha J Hinojos
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
| | - Paul R Sabandal
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
| | - Peter D Evans
- The Inositide Laboratory, The Babraham InstituteCambridge, United Kingdom
| | - Kyung-An Han
- Neuromodulation Disorders Cluster at Border Biomedical Research Center, Department of Biological Sciences, University of Texas at El PasoEl Paso, TX, United States
| |
Collapse
|
6
|
Effects of high-frequency stimulation of the nucleus accumbens on the development and expression of ethanol sensitization in mice. Behav Pharmacol 2015; 26:184-92. [DOI: 10.1097/fbp.0000000000000033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
7
|
Tran S, Gerlai R. Recent advances with a novel model organism: alcohol tolerance and sensitization in zebrafish (Danio rerio). Prog Neuropsychopharmacol Biol Psychiatry 2014; 55:87-93. [PMID: 24593943 PMCID: PMC4225077 DOI: 10.1016/j.pnpbp.2014.02.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 02/06/2014] [Accepted: 02/06/2014] [Indexed: 11/18/2022]
Abstract
Alcohol abuse and dependence are a rapidly growing problem with few treatment options available. The zebrafish has become a popular animal model for behavioral neuroscience. This species may be appropriate for investigating the effects of alcohol on the vertebrate brain. In the current review, we examine the literature by discussing how alcohol alters behavior in zebrafish and how it may affect biological correlates. We focus on two phenomena that are often examined in the context of alcohol-induced neuroplasticity. Alcohol tolerance (a progressive decrease in the effect of alcohol over time) is often observed following continuous (chronic) exposure to low concentrations of alcohol. Alcohol sensitization also called reverse tolerance (a progressive increase in the effect of alcohol over time) is often observed following repeated discrete exposures to higher concentrations of alcohol. These two phenomena may underlie the development and maintenance of alcohol addiction. The phenotypical characterization of these responses in zebrafish may be the first important steps in establishing this species as a tool for the analysis of the molecular and neurobiological mechanisms underlying human alcohol addiction.
Collapse
Affiliation(s)
- Steven Tran
- University of Toronto, Department of Cell and Systems Biology, Canada
| | - Robert Gerlai
- University of Toronto, Department of Cell and Systems Biology, Canada; University of Toronto at Mississauga, Department of Psychology, Canada.
| |
Collapse
|
8
|
Gomes I, Fujita W, Chandrakala MV, Devi LA. Disease-specific heteromerization of G-protein-coupled receptors that target drugs of abuse. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 117:207-65. [PMID: 23663971 DOI: 10.1016/b978-0-12-386931-9.00009-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Drugs of abuse such as morphine or marijuana exert their effects through the activation of G-protein-coupled receptors (GPCRs), the opioid and cannabinoid receptors, respectively. Moreover, interactions between either of these receptors have been shown to be involved in the rewarding effects of drugs of abuse. Recent advances in the field, using a variety of approaches, have demonstrated that many GPCRs, including opioid, cannabinoid, and dopamine receptors, can form associations between different receptor subtypes or with other GPCRs to form heteromeric complexes. The formation of these complexes, in turn, leads to the modulation of the properties of individual protomers. The development of tools that can selectively disrupt GPCR heteromers as well as monoclonal antibodies that can selectively block signaling by specific heteromer pairs has indicated that heteromers involving opioid, cannabinoid, or dopamine receptors may play a role in various disease states. In this review, we describe evidence for opioid, cannabinoid, and dopamine receptor heteromerization and the potential role of GPCR heteromers in pathophysiological conditions.
Collapse
Affiliation(s)
- Ivone Gomes
- Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York, USA
| | | | | | | |
Collapse
|
9
|
Bambico FR, Lacoste B, Hattan PR, Gobbi G. Father absence in the monogamous california mouse impairs social behavior and modifies dopamine and glutamate synapses in the medial prefrontal cortex. Cereb Cortex 2013; 25:1163-75. [PMID: 24304503 DOI: 10.1093/cercor/bht310] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The role of the father in psycho-affective development is indispensable. Yet, the neurobehavioral effects of paternal deprivation (PD) are poorly understood. Here, we examined the behavioral consequences of PD in the California mouse, a species displaying monogamous bonding and biparental care, and assessed its impact on dopamine (DA), serotonin (5-HT), and glutamate (GLU) transmission in the medial prefrontal cortex (mPFC). In adult males, deficits in social interaction were observed, when a father-deprived (PD) mouse was matched with a PD partner. In adult females, deficits were observed when matching a PD animal with a non-PD control, and when matching 2 PD animals. PD also increased aggression in females. Behavioral abnormalities in PD females were associated with a sensitized response to the locomotor-activating effect of amphetamine. Following immunocytochemical demonstration of DA, 5-HT, and GLU innervations in the mPFC, we employed in vivo electrophysiology and microiontophoresis, and found that PD attenuated the basal activity of low-spiking pyramidal neurons in females. PD decreased pyramidal responses to DA in females, while enhancing responses to NMDA in both sexes. We thus demonstrate that, during critical neurodevelopmental periods, PD leads to sex-dependent abnormalities in social and reward-related behaviors that are associated with disturbances in cortical DA and GLU neurotransmission.
Collapse
Affiliation(s)
- Francis R Bambico
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC H3A 1A1, Canada and Behavioral Neurobiology Laboratory, Center for Addiction and Mental Health, Toronto, ON M5T 1R8, Canada
| | - Baptiste Lacoste
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC H3A 1A1, Canada and
| | - Patrick R Hattan
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC H3A 1A1, Canada and
| | - Gabriella Gobbi
- Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University Health Center, McGill University, Montreal, QC H3A 1A1, Canada and
| |
Collapse
|
10
|
Nona CN, Li R, Nobrega JN. Altered NMDA receptor subunit gene expression in brains of mice showing high vs. low sensitization to ethanol. Behav Brain Res 2013; 260:58-66. [PMID: 24315834 DOI: 10.1016/j.bbr.2013.11.037] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 11/16/2013] [Accepted: 11/22/2013] [Indexed: 12/26/2022]
Abstract
Repeated administration of ethanol (EtOH) in mice leads to behavioural sensitization, a progressive increase in locomotor activity. Since not all mice sensitize equally to EtOH, the objective of the present study was to determine whether variability in this response is associated with altered subunit gene expression of the N-methyl-d-aspartate receptor (NMDAR), a primary target of EtOH. We examined NR1, NR2A, and NR2B expression throughout the brain during the development phase of EtOH sensitization, as well as after a 14 day withdrawal period. Male DBA/2J mice received 5-6 injections of EtOH (2.2g/kg, i.p.) or saline (SAL) and were categorized as high- (HS) or low-sensitized (LS) on the basis of locomotor activity scores after the final injection. NMDAR subunits were analyzed by in situ hybridization in brains removed either immediately following the final EtOH injection or 14 days thereafter. At the end of development phase, LS mice showed increased NR2A expression in several brain areas compared to saline controls. LS animals also had greater NR1 expression in the nucleus accumbens core (+11%, p=0.05) and shell (+14%, p=0.04) compared to HS mice, and increased NR2B expression in hippocampal CA1 (+20%, p=0.05) relative to saline-treated animals. High-sensitized mice showed increased NR2A expression in the bed nucleus of the stria terminalis when compared to controls (+54%, p=0.02). No differences in gene expression between the treatment groups were seen 14 days after the final injection. These findings suggest that region-specific NMDAR subunits may play an important role in the variability associated with the induction of EtOH sensitization. Low-sensitized mice may be more sensitive to the NMDAR inhibitory effects of EtOH, with the NR1 and NR2A subunits potentially playing a key role in the failure to sensitize upon repeated EtOH exposure.
Collapse
Affiliation(s)
- Christina N Nona
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada; Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Rui Li
- Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - José N Nobrega
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada; Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health, Toronto, ON, Canada; Department of Psychiatry, University of Toronto, Toronto, ON, Canada; Department of Psychology, University of Toronto, Toronto, ON, Canada.
| |
Collapse
|
11
|
Nona CN, Guirguis S, Nobrega JN. Susceptibility to ethanol sensitization is differentially associated with changes in pCREB, trkB and BDNF mRNA expression in the mouse brain. Behav Brain Res 2013; 242:25-33. [PMID: 23291223 DOI: 10.1016/j.bbr.2012.12.035] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Revised: 12/16/2012] [Accepted: 12/21/2012] [Indexed: 11/30/2022]
Abstract
Repeated exposure to ethanol in mice induces behavioural sensitization, a progressive increase in locomotor activity that is common to drugs of abuse. Not all mice however show sensitization to ethanol. The goal of the present study was to examine whether variability in the sensitization response to ethanol (EtOH) is differentially associated with regional brain changes in specific molecular markers associated with neuroplasticity, namely BDNF and its receptor trkB, and levels of phosphorylated cyclic AMP-regulated element-binding protein (pCREB), 14 days after withdrawal from chronic, intermittent EtOH exposure. Male DBA/2NCrl mice received 7 biweekly EtOH (2.2g/kg, i.p.) or saline (SAL) injections and were classified as Sensitized or Non-sensitized on the basis of final locomotor activity (LMA) scores. Brains were removed two weeks later for immunohistochemical and in situ hybridization analyses. Compared to SAL-treated and Non-sensitized mice, Sensitized animals showed a higher number of pCREB-immunoreactive cells in the nucleus accumbens shell (+68% and +50%, respectively) and in the bed nucleus of the stria terminalis (+61% and 46%, respectively), whereas SAL and Non-sensitized groups did not differ from each other. A different pattern was seen when BDNF and trkB mRNA levels were analyzed in the same groups. Non-sensitized mice displayed lower BDNF mRNA in several brain areas and significantly lower trkB levels throughout the brain when compared to either the Sensitized or to SAL groups, which did not differ from each other. These results indicate that sensitization to EtOH is differentially associated with increased pCREB levels in specific brain areas. The observed decrease in BDNF and trkB mRNA in the Non-sensitized group suggests the possibility that EtOH may have neurotoxic effects in a subpopulation of mice, which might in turn prevent the development of behavioural sensitization. The lack of a difference in BDNF and trkB mRNA expression between Sensitized and SAL mice suggests that EtOH sensitization may be mediated by mechanisms different from those mediating sensitization to other psychostimulants.
Collapse
Affiliation(s)
- Christina N Nona
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | | | | |
Collapse
|
12
|
Differential regulation of motor control and response to dopaminergic drugs by D1R and D2R neurons in distinct dorsal striatum subregions. EMBO J 2011; 31:640-53. [PMID: 22068054 DOI: 10.1038/emboj.2011.400] [Citation(s) in RCA: 155] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 10/12/2011] [Indexed: 12/17/2022] Open
Abstract
The dorsal striatum is critically involved in a variety of motor behaviours, including regulation of motor activity, motor skill learning and motor response to psychostimulant and neuroleptic drugs, but contribution of D(2)R-striatopallidal and D(1)R-striatonigral neurons in the dorsomedial (DMS, associative) and dorsolateral (DLS, sensorimotor) striatum to distinct functions remains elusive. To delineate cell type-specific motor functions of the DMS or the DLS, we selectively ablated D(2)R- and D(1)R-expressing striatal neurons with spatial resolution. We found that associative striatum exerts a population-selective control over locomotion and reactivity to novelty, striatopallidal and striatonigral neurons inhibiting and stimulating exploration, respectively. Further, DMS-striatopallidal neurons are involved only in early motor learning whereas gradual motor skill acquisition depends on striatonigral neurons in the sensorimotor striatum. Finally, associative striatum D(2)R neurons are required for the cataleptic effect of the typical neuroleptic drug haloperidol and for amphetamine motor response sensitization. Altogether, these data provide direct experimental evidence for cell-specific topographic functional organization of the dorsal striatum.
Collapse
|
13
|
The effects of pramipexole on prepulse inhibition and locomotor activity in C57BL/6J mice. Behav Pharmacol 2010; 21:135-43. [PMID: 20215963 DOI: 10.1097/fbp.0b013e328337be7e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Pramipexole (PRA) is a preferential D3R agonist that, in rats and humans, modifies prepulse inhibition (PPI) of the acoustic startle reflex, an operational measure of sensorimotor gating. The ability to use similar PPI measures across species, and the relative ease of genetic manipulations in mice, suggests that molecular studies of the D3R regulation of sensorimotor gating might be best pursued in mice. Here, we evaluate the effects of PRA on PPI and locomotion in C57BL/6J mice, the background strain for many gene knockout mouse models. Male C57BL/6J mice were tested for PPI and locomotor activity after injection of PRA. No significant effects of PRA on PPI were observed at any dose (0.1-10.0 mg/kg), but a significant reduction in startle magnitude was observed after 10 mg/kg PRA. In contrast, the D1/2 agonist, apomorphine (5 mg/kg) significantly reduced PPI in these mice. At doses of PRA that did not alter startle magnitude (0.3, 1, 3 mg/kg), significant decreases in the amount of locomotor and investigatory behavior were observed. Distinct from findings in rats and humans, it seems that either: (i) PRA does not activate D3Rs in C57BL/6J mice, or (ii) D3R agonists are not sufficient to alter PPI in this mouse strain.
Collapse
|
14
|
Sander SE, Raymond R, Nobrega JN, Richter A. Autoradiographic and pharmacological studies on the role of dopamine D3 receptors in genetically dystonic (dt(sz)) hamsters. Pharmacol Biochem Behav 2010; 96:136-40. [PMID: 20451545 DOI: 10.1016/j.pbb.2010.04.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 04/15/2010] [Accepted: 04/28/2010] [Indexed: 11/30/2022]
Abstract
Previous examinations demonstrated periodic increases in striatal extracellular dopamine levels during dystonic attacks and changes in dopamine D1 and D2 receptor binding in the dt(sz) mutant hamster, an animal model of paroxysmal non-kinesiogenic dyskinesia in which dystonic episodes can be induced by stress. Since dopamine D3 receptors are involved in the regulation of striatal dopamine release, D3 receptor function was investigated by autoradiographic and pharmacological examinations in mutant hamsters in the present study. [(125)I]7-[[(E)-3-iodoprop-2-enyl]-propylamino]-5,6,7,8-tetrahydronaphthalen-2-ol ([(125)I]7-OH-PIPAT) binding was not significantly altered in the striatum, n. accumbens, ventral pallidum or cerebellum in dt(sz) hamsters in comparison to non-dystonic control hamsters. In line with the unaltered D3 receptor binding, the preferential dopamine D3 versus D2 receptor antagonist U-99194 (5,6-dimethoxy-N,N-dipropyl-2,3-dihydro-1H-inden-2-amine hydrochloride) did not exert significant effects on the severity of dystonia in dt(sz) hamsters at doses of 10 to 40mg/kg which induced hyperlocomotion. These results suggest that periodic elevations of dopamine levels in these animals are not related to D3 receptor dysfunctions.
Collapse
Affiliation(s)
- Svenja E Sander
- Institute of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, 14195 Berlin, Germany
| | | | | | | |
Collapse
|
15
|
Sora I, Li B, Igari M, Hall FS, Ikeda K. Transgenic mice in the study of drug addiction and the effects of psychostimulant drugs. Ann N Y Acad Sci 2010; 1187:218-46. [PMID: 20201856 DOI: 10.1111/j.1749-6632.2009.05276.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The first transgenic models used to study addiction were based upon a priori assumptions about the importance of particular genes in addiction, including the main target molecules of morphine, amphetamine, and cocaine. This consequently emphasized the importance of monoamine transporters, opioid receptors, and monoamine receptors in addiction. Although the effects of opiates were largely eliminated by mu opioid receptor gene knockout, the case for psychostimulants was much more complex. Research using transgenic models supported the idea of a polygenic basis for psychostimulant effects and has associated particular genes with different behavioral consequences of psychostimulants. Phenotypic analysis of transgenic mice, especially gene knockout mice, has been instrumental in identifying the role of specific molecular targets of addictive drugs in their actions. In this article, we summarize studies that have provided insight into the polygenic determination of drug addiction phenotypes in ways that are not possible with other methods, emphasizing research into the effects of psychostimulant drugs in gene knockouts of the monoamine transporters and monoamine receptors.
Collapse
Affiliation(s)
- Ichiro Sora
- Department of Biological Psychiatry, Tohoku University Graduate School of Medicine, Sendai, Japan.
| | | | | | | | | |
Collapse
|
16
|
A functional role for the dopamine D3 receptor in the induction and expression of behavioural sensitization to ethanol in mice. Psychopharmacology (Berl) 2009; 207:47-56. [PMID: 19662386 DOI: 10.1007/s00213-009-1629-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Accepted: 07/21/2009] [Indexed: 10/20/2022]
Abstract
RATIONALE We previously reported that mice lacking dopamine D3 receptors (D3R) were resistant to behavioural sensitization to ethanol (EtOH). Since knockout mice have permanent receptor inactivation, we investigated how temporary pharmacological blockade and activation of D3Rs affected the induction or expression of EtOH sensitization. MATERIALS AND METHOD In induction studies, DBA/2 mice received 0, 10 or 75 mg/kg, subcutaneous (s.c.) of the D3R antagonist, U99194A ,before each of seven EtOH (2.2 g/kg, intraperitoneal) or saline injections. Locomotor activity (LMA) was assessed in activity chambers. In expression studies, mice received seven injections of EtOH or saline, followed 14 days later with U99194A or vehicle immediately before a test dose of EtOH (1.8 g/kg). In separate experiments, the effects of the D3R agonist PD128907 (0.01 mg/kg, s.c.) were similarly examined during and after EtOH sensitization. RESULTS Chronic co-administration of low-dose U99194A blocked the induction of EtOH sensitization, while acute U99194A had no effect in mice that were already sensitized. Chronic co-administration of PD128907 resulted in decreased LMA but this effect was also seen in saline-treated mice, suggesting a simple subtractive effect. In previously sensitized mice, acute PD128907 significantly attenuated the expression of EtOH sensitization, indicating an enhanced response to the drug. CONCLUSIONS Results suggest a modulatory role for the D3R in behavioural sensitization to EtOH, where D3R blockade is associated with induction and D3R stimulation is associated with expression of EtOH sensitization. A model is suggested to account for these complementary functions of the D3R at different stages of EtOH sensitization.
Collapse
|