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Xu S, Kang UG. Region-specific alterations in the expression and phosphorylation of NMDA receptor subunits in the rat prefrontal cortex and dorsal striatum accompanying behavioral sensitization induced by cocaine and ethanol. Pharmacol Biochem Behav 2024; 236:173711. [PMID: 38253241 DOI: 10.1016/j.pbb.2024.173711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/15/2024] [Accepted: 01/17/2024] [Indexed: 01/24/2024]
Abstract
Behavioral sensitization is defined as the enhanced behavioral response to drugs of abuse after repeated exposure, which can serve as a behavioral model of addiction. Our previous study demonstrated that behavioral cross-sensitization occurs between cocaine and ethanol, suggesting commonalities between these drugs. N-methyl-d-aspartate (NMDA) receptors play important roles in synaptic plasticity, learning, memory, and addiction-associated behaviors. However, little is known about whether NMDA receptor-mediated signaling regulation is a common feature following behavioral sensitizations induced by cocaine and ethanol. Thus, the present study examined the expression of phospho-S896-NR1, NR2A, and NR2B subunits in the prefrontal cortex and dorsal striatum following reciprocal cross-sensitization between cocaine and ethanol. We also examined the mRNA expression of the NR2A and NR2B subunits. In the ethanol-sensitized state, phosphorylation of NR1 and expression of NR2A and NR2B subunits were increased in both the prefrontal cortex and dorsal striatum. In the cocaine-sensitized state, phosphorylation of NR1 and expression of the NR2A and NR2B subunits were increased in the prefrontal cortex but not in the dorsal striatum. Corresponding changes in mRNA expression were observed in the ethanol-sensitized state but not in the cocaine-sensitized state. Acute treatment with either cocaine or ethanol had no effect on the phosphorylation and expression of NMDA receptor subunits in either the prefrontal cortex or dorsal striatum, regardless of the sensitization state. These results indicate a partially overlapping neural mechanism for cocaine and ethanol that may induce the development of behavioral sensitization.
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Affiliation(s)
- Shijie Xu
- Medical Research Center, Affiliated Cancer Hospital of Hainan Medical University, Haikou 570312, China; Institute of Human Behavioral Medicine, Medical Research Center, Seoul National University, Seoul 03080, Republic of Korea
| | - Ung Gu Kang
- Institute of Human Behavioral Medicine, Medical Research Center, Seoul National University, Seoul 03080, Republic of Korea; Department of Psychiatry and Behavioral Science, Seoul National University College of Medicine, Seoul 03080, Republic of Korea.
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Shahen-Zoabi S, Smoum R, Beiser T, Nemirovski A, Mechoulam R, Yaka R. N-Oleoyl Glycine and Its Derivatives Attenuate the Acquisition and Expression of Cocaine-Induced Behaviors. Cannabis Cannabinoid Res 2023; 8:812-823. [PMID: 35647907 DOI: 10.1089/can.2022.0005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Introduction: The endocannabinoid system (ECS) plays a key modulatory role during synaptic plasticity and homeostatic processes in the brain and plays an important role in the neurobiological processes underlying drug addiction. Impaired endocannabinoid (eCB) signaling contributes to dysregulated synaptic plasticity, increased stress responsivity, and craving that propel addiction. Therefore, we hypothesized that boosting the ECS by exogenous administration of selective eCBs will attenuate cocaine-induced behaviors. Materials and Methods: The behavioral paradigms included psychomotor sensitization (PS) and conditioned place preference (CPP). Liquid chromatography-mass spectrometry analysis was used for quantitative profiling of eCBs in mouse brain. Results: We first measured the levels of eCBs in different brain areas of the reward system following chronic cocaine treatment. We found that following daily administration of cocaine, the levels of N-oleoyl glycine (OlGly) were significantly elevated in the nucleus accumbens (NAc) in a region-specific manner. We next tested whether administration of OlGly will attenuate cocaine-induced behaviors. We found that administration of OlGly during withdrawal, but not during acquisition of PS, attenuated the expression of cocaine sensitization. In addition, the administration of OlGly during the acquisition of cocaine CPP, but not during withdrawal, attenuated the expression of cocaine-conditioned reward. To enhance the stability of OlGly and its duration of action, two methylated derivatives of OlGly were synthesized, the monomethylated OlGly (HU-595) and dimethylated OlGly (HU-596). We found that the effect of administration of HU-595 or HU-596 during cocaine conditioning did not differ from the OlGly-induced decrease in the expression of CPP. Conclusion: Our findings suggest that the ECS is involved in the common neurobiological mechanisms underlying the development and expression of cocaine reward and drug-seeking. Boosting the ECS exogenously has beneficial effects against cocaine-induced behaviors.
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Affiliation(s)
- Samah Shahen-Zoabi
- Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Reem Smoum
- Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Tehila Beiser
- Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Alina Nemirovski
- Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Raphael Mechoulam
- Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Rami Yaka
- Institute for Drug Research (IDR), School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
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3
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Li DC, Pitts EG, Dighe NM, Gourley SL. GluN2B inhibition confers resilience against long-term cocaine-induced neurocognitive sequelae. Neuropsychopharmacology 2023; 48:1108-1117. [PMID: 36056105 PMCID: PMC10209078 DOI: 10.1038/s41386-022-01437-8] [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: 03/31/2022] [Revised: 07/26/2022] [Accepted: 08/17/2022] [Indexed: 01/02/2023]
Abstract
Cocaine self-administration can disrupt the capacity of humans and rodents to flexibly modify familiar behavioral routines, even when they become maladaptive or unbeneficial. However, mechanistic factors, particularly those driving long-term behavioral changes, are still being determined. Here, we capitalized on individual differences in oral cocaine self-administration patterns in adolescent mice and revealed that the post-synaptic protein PSD-95 was reduced in the orbitofrontal cortex (OFC) of escalating, but not stable, responders, which corresponded with later deficits in flexible decision-making behavior. Meanwhile, NMDA receptor GluN2B subunit content was lower in the OFC of mice that were resilient to escalatory oral cocaine seeking. This discovery led us to next co-administer the GluN2B-selective antagonist ifenprodil with cocaine, blocking the later emergence of cocaine-induced decision-making abnormalities. GluN2B inhibition also prevented cocaine-induced dysregulation of neuronal structure and function in the OFC, preserving mature, mushroom-shaped dendritic spine densities on deep-layer pyramidal neurons, which were otherwise lower with cocaine, and safeguarding functional BLA→OFC connections necessary for action flexibility. We posit that cocaine potentiates GluN2B-dependent signaling, which triggers a series of durable adaptations that result in the dysregulation of post-synaptic neuronal structure in the OFC and disruption of BLA→OFC connections, ultimately weakening the capacity for flexible choice. And thus, inhibiting GluN2B-NMDARs promotes resilience to long-term cocaine-related sequelae.
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Affiliation(s)
- Dan C Li
- Medical Scientist Training Program, Emory University School of Medicine, Atlanta, GA, USA
- Department of Pediatrics, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Emory University, Atlanta, GA, USA
| | - Elizabeth G Pitts
- Department of Pediatrics, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Emory University, Atlanta, GA, USA
| | - Niharika M Dighe
- Department of Pediatrics, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Emory University, Atlanta, GA, USA
| | - Shannon L Gourley
- Department of Pediatrics, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA.
- Emory National Primate Research Center, Emory University, Atlanta, GA, USA.
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4
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Chiamulera C, Piva A, Abraham WC. Glutamate receptors and metaplasticity in addiction. Curr Opin Pharmacol 2020; 56:39-45. [PMID: 33128937 DOI: 10.1016/j.coph.2020.09.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/10/2020] [Accepted: 09/10/2020] [Indexed: 12/12/2022]
Abstract
Chronic drug use is a neuroadaptive disorder characterized by strong and persistent plasticity in the mesocorticolimbic reward system. Long-lasting effects of drugs of abuse rely on their ability to hijack glutamate receptor activity and long-term synaptic plasticity processes like long-term potentiation and depression. Importantly, metaplasticity-based modulation of synaptic plasticity contributes to durable neurotransmission changes in mesocorticolimbic pathways including the ventral tegmental area and the nucleus accumbens, causing 'maladaptive' drug memory and higher risk for drug-seeking relapse. On the other hand, drug-induced metaplasticity can make appetitive memories more malleable to modification, offering a potential target mechanism for intervention. Here we review the literature on the role of glutamate receptors in addiction-related metaplasticity phenomena.
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Affiliation(s)
- Cristiano Chiamulera
- Neuropsychopharmacology Lab, Section Pharmacology, Department Diagnostic & Public Health, University of Verona, Verona, Italy.
| | - Alessandro Piva
- Neuropsychopharmacology Lab, Section Pharmacology, Department Diagnostic & Public Health, University of Verona, Verona, Italy
| | - Wickliffe C Abraham
- Department of Psychology, Brain Health Research Centre, Brain Research New Zealand, University of Otago, Dunedin, New Zealand
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Leyrer-Jackson JM, Piña JA, McCallum J, Foster Olive M, Gipson CD. Direct administration of ifenprodil and citalopram into the nucleus accumbens inhibits cue-induced nicotine seeking and associated glutamatergic plasticity. Brain Struct Funct 2020; 225:1967-1978. [PMID: 32591928 DOI: 10.1007/s00429-020-02103-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 06/16/2020] [Indexed: 12/27/2022]
Abstract
Nicotine use disorder has been associated with glutamatergic alterations within the basal ganglia that might contribute to relapse. Specifically, initiation of cue-induced nicotine seeking produces rapid, transient synaptic potentiation (t-SP) in nucleus accumbens core (NAcore) medium spiny neurons (MSNs), defined as increases in spine head diameter and AMPA to NMDA current ratios (A/N). Ifenprodil, which inhibits nicotine reinstatement when administered systemically, antagonizes GluN2B-containing NMDA receptors, has affinity for serotonin receptors, and blocks serotonin transporters (SERT). The mechanisms underlying its therapeutic efficacy, however, remain unknown. Using pharmacological and genetic approaches, the current study examined the role of NAcore GluN2B receptors as well as SERT in mediating cue-induced nicotine seeking and associated MSN structure and physiology. Prior to reinstatement, rats received intra-NAcore injections of either ifenprodil, citalopram or artificial cerebral spinal fluid (15 min prior), or GluN2B or control siRNAs (3 consecutive days prior). Rats were sacrificed after a 15-min cue-induced reinstatement session for dendritic spine analysis, western blotting or whole-cell electrophysiology. Intra-NAcore ifenprodil blocked nicotine-seeking behavior and promoted a higher frequency of shorter spines on MSN dendrites. However, a decrease in membrane-bound GluN2B receptor expression did not prevent cue-induced nicotine seeking or associated MSN cell physiology. Interestingly, intra-NAcore citalopram, an SSRI, prevented cue-induced nicotine seeking. Together, these results indicate that the therapeutic effects of ifenprodil on cue-induced nicotine seeking may, in part, be due to its actions at SERT rather than GluN2B, which may be specific to nicotine-seeking as opposed to other drugs of abuse.
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Affiliation(s)
| | - Jose A Piña
- Department of Psychology, Arizona State University, Tempe, AZ, USA
| | - Joseph McCallum
- Department of Psychology, Arizona State University, Tempe, AZ, USA
| | - M Foster Olive
- Department of Psychology, Arizona State University, Tempe, AZ, USA
| | - Cassandra D Gipson
- Department of Family and Community Medicine, University of Kentucky, 741 S. Limestone, BBSRB Room 363, Lexington, KY, 40536, USA.
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6
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Smaga I, Sanak M, Filip M. Cocaine-induced Changes in the Expression of NMDA Receptor Subunits. Curr Neuropharmacol 2020; 17:1039-1055. [PMID: 31204625 PMCID: PMC7052821 DOI: 10.2174/1570159x17666190617101726] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 05/31/2019] [Accepted: 06/11/2019] [Indexed: 11/28/2022] Open
Abstract
Cocaine use disorder is manifested by repeated cycles of drug seeking and drug taking. Cocaine exposure causes synaptic transmission in the brain to exhibit persistent changes, which are poorly understood, while the pharmacotherapy of this disease has not been determined. Multiple potential mechanisms have been indicated to be involved in the etiology of co-caine use disorder. The glutamatergic system, especially N-methyl-D-aspartate (NMDA) receptors, may play a role in sever-al physiological processes (synaptic plasticity, learning and memory) and in the pathogenesis of cocaine use disorder. The composition of the NMDA receptor subunits changes after contingent and noncontingent cocaine administration and after drug abstinence in a region-specific and time-dependent manner, as well as depending on the different protocols used for co-caine administration. Changes in the expression of NMDA receptor subunits may underlie the transition from cocaine abuse to dependence, as well as the transition from cocaine dependence to cocaine withdrawal. In this paper, we summarize the cur-rent knowledge regarding neuroadaptations within NMDA receptor subunits and scaffolding proteins observed following voluntary and passive cocaine intake, as well as the effects of NMDA receptor antagonists on cocaine-induced behavioral changes during cocaine seeking and relapse.
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Affiliation(s)
- Irena Smaga
- Department of Internal Medicine, Jagiellonian University Medical College, Skawińska 8, PL 31-066 Kraków, Poland.,Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smętna 12, PL 31-343 Kraków, Poland
| | - Marek Sanak
- Department of Internal Medicine, Jagiellonian University Medical College, Skawińska 8, PL 31-066 Kraków, Poland
| | - Małgorzata Filip
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smętna 12, PL 31-343 Kraków, Poland
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Yates JR, Prior NA, Chitwood MR, Day HA, Heidel JR, Hopkins SE, Muncie BT, Paradella-Bradley TA, Sestito AP, Vecchiola AN, Wells EE. Effects of GluN2B-selective antagonists on delay and probability discounting in male rats: Modulation by delay/probability presentation order. Exp Clin Psychopharmacol 2018; 26:525-540. [PMID: 30035577 PMCID: PMC6283694 DOI: 10.1037/pha0000216] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The contribution of the GluN2B subunit of the NMDA receptor to impulsivity has recently been examined. Ro 63-1908, a highly selective antagonist for the GluN2B, decreases impulsive choice. Because the order in which delays are presented modulates drug effects in discounting procedures, one goal of the current study was to determine the effects of Ro 63-1908 in delay discounting procedures in which the delays to obtaining the large reinforcer either increase or decrease across the session. We also determined if Ro 63-1908 differentially alters risky choice in probability discounting procedures that use ascending/descending schedules. Male rats were trained in either delay (n = 24) or probability (n = 24) discounting in which the delay to/odds against reinforcement were presented in either ascending or descending order (n = 12 each schedule). Following training, rats received the GluN2B antagonists Ro 63-1908 (0-1.0 mg/kg) and CP-101,606 (0-3.0 mg/kg). In delay discounting, Ro 63-1908 (1.0 mg/kg), but not CP-101,606, decreased choice for the large reinforcer, but only when the delays decreased across the session. In probability discounting, Ro 63-1908 (0.3 mg/kg)/CP-101,606 (1.0 mg/kg) increased choice for the large reinforcer when the probability of obtaining this alternative decreased across the session, but Ro 63-1908 (1.0 mg/kg)/CP-101,606 (3.0 mg/kg) decreased choice when the probabilities increased. These results show that the GluN2B is a mediator of impulsive/risky choice, but the effects of GluN2B antagonists are dependent on the order in which delays/probabilities are presented. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
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8
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Guzman D, Carreira MB, Friedman AK, Adachi M, Neve RL, Monteggia LM, Han MH, Cowan CW, Self DW. Inactivation of NMDA Receptors in the Ventral Tegmental Area during Cocaine Self-Administration Prevents GluA1 Upregulation but with Paradoxical Increases in Cocaine-Seeking Behavior. J Neurosci 2018; 38:575-585. [PMID: 29196318 PMCID: PMC5777111 DOI: 10.1523/jneurosci.2828-16.2017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/09/2017] [Accepted: 11/17/2017] [Indexed: 01/20/2023] Open
Abstract
Cocaine self-administration increases expression of GluA1 subunits in ventral tegmental area (VTA) dopamine neurons, which subsequently enhance the motivation for cocaine. This increase in GluA1 may be dependent on concomitant NMDA receptor (NMDAR) activation during self-administration, similar to cocaine-induced long-term potentiation in the VTA. In this study, we used viral-mediated expression of a dominant-negative GluN1 subunit (HSV-dnGluN1) in VTA neurons to study the effect of transient NMDAR inactivation on the GluA1 increases induced by chronic cocaine self-administration in male rats. We found that dnGluN1 expression in the VTA limited to the 3 weeks of cocaine self-administration prevents the subsequent increase in tissue GluA1 levels when compared with control infusions of HSV-LacZ. Surprisingly, dnGluN1 expression led to an enhancement in the motivation to self-administer cocaine as measured using a progressive ratio reinforcement schedule and to enhanced cocaine seeking measured in extinction/reinstatement tests following an extended 3 week withdrawal period. Despite blocking tissue GluA1 increases in cocaine self-administering animals, the HSV-dnGluN1 treatment resulted in increased membrane levels of GluA1 and GluN2B, along with markedly higher locomotor responses to intra-VTA infusions of AMPA, suggesting a paradoxical increase in VTA AMPA receptor responsiveness. Together, these data suggest that NMDARs mediate cocaine-induced increases in VTA GluA1 expression, but such transient NMDAR inactivation also leads to compensatory scaling of synaptic AMPA receptors that enhance the motivational for cocaine.SIGNIFICANCE STATEMENT Dopamine neurons in the ventral tegmental area (VTA) are critical substrates of drug rewards. Animal models indicate that chronic cocaine use enhances excitatory glutamatergic input to these neurons, making them more susceptible to environmental stimuli that trigger drug craving and relapse. We previously found that self-administration of cocaine increases AMPA glutamate receptors in the VTA, and this effect enhances motivation for cocaine. Here we report that the mechanism for this upregulation involves NMDA receptor activity during cocaine use. While interference with NMDA receptor function blocks AMPA receptor upregulation, it also produces a paradoxical enhancement in membrane AMPA receptor subunits, AMPA responsiveness, and the motivation for cocaine. Thus, pharmacotherapy targeting NMDA receptors may inadvertently produce substantial adverse consequences for cocaine addiction.
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Affiliation(s)
- Daniel Guzman
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Maria B Carreira
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Allyson K Friedman
- Department of Pharmacological Sciences, Institute for Systems Biomedicine, and
| | - Megumi Adachi
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Rachael L Neve
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | - Lisa M Monteggia
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - Ming-Hu Han
- Department of Pharmacological Sciences, Institute for Systems Biomedicine, and
- Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, New York 10029, and
| | - Christopher W Cowan
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390
| | - David W Self
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390,
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Li MH, Underhill SM, Reed C, Phillips TJ, Amara SG, Ingram SL. Amphetamine and Methamphetamine Increase NMDAR-GluN2B Synaptic Currents in Midbrain Dopamine Neurons. Neuropsychopharmacology 2017; 42:1539-1547. [PMID: 27976681 PMCID: PMC5436114 DOI: 10.1038/npp.2016.278] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 11/29/2016] [Accepted: 12/11/2016] [Indexed: 02/07/2023]
Abstract
The psychostimulants amphetamine (AMPH) and methamphetamine (MA) are widely abused illicit drugs. Here we show that both psychostimulants acutely increase NMDA receptor (NMDAR)-mediated synaptic currents and decrease AMPA receptor (AMPAR)/NMDAR ratios in midbrain dopamine neurons. The potentiation depends on the transport of AMPH into the cell by the dopamine transporter. NMDAR-GluN2B receptor inhibitors, ifenprodil, RO 25-6981, and RO 04-5595, inhibit the potentiation without affecting basal-evoked NMDA currents, indicating that NMDAR-GluN2B receptors are activated by AMPH. A selective peptide inhibitor of AMPH-dependent trafficking of the neuronal excitatory amino acid transporter 3 (EAAT3) blocks potentiation, suggesting that EAAT3 internalization increases extracellular glutamate concentrations and activates GluN2B-containing NMDARs. Experiments with the use-dependent NMDAR blocker, MK-801, indicate that potentiated NMDARs reside on the plasma membrane and are not inserted de novo. In behavioral studies, GluN2B inhibitors reduce MA-mediated locomotor activity, without affecting basal activity. These results reveal an important interaction between dopamine and glutamatergic signaling in midbrain dopamine neurons in response to acute administration of psychostimulants.
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Affiliation(s)
- Ming-Hua Li
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, USA
| | - Suzanne M Underhill
- National Institute of Mental Health, National Institutes of Health, Laboratory of Molecular and Cellular Neurobiology, Bethesda, MD, USA
| | - Cheryl Reed
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, USA
| | - Tamara J Phillips
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, USA,VA Portland Health Care System, Portland, OR, USA
| | - Susan G Amara
- National Institute of Mental Health, National Institutes of Health, Laboratory of Molecular and Cellular Neurobiology, Bethesda, MD, USA
| | - Susan L Ingram
- Department of Neurological Surgery, Oregon Health & Science University, Portland, OR, USA,Department of Neurological Surgery, Oregon Health & Science University (OHSU), 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA, Tel: 503 494 1220, Fax: 503 494 2664, E-mail:
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10
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Cocaine-induced changes in NMDA receptor signaling. Mol Neurobiol 2014; 50:494-506. [PMID: 24445951 DOI: 10.1007/s12035-014-8636-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 01/02/2014] [Indexed: 01/27/2023]
Abstract
Addictive states are often thought to rely on lasting modification of signaling at relevant synapses. A long-standing theory posits that activity at N-methyl-D-aspartate receptors (NMDARs) is a critical component of long-term synaptic plasticity in many brain areas. Indeed, NMDAR signaling has been found to play a role in the etiology of addictive states, in particular, following cocaine exposure. However, no consensus is apparent with respect to the specific effects of cocaine exposure on NMDARs. Part of the difficulty lies in the fact that NMDARs interact extensively with multiple membrane proteins and intracellular signaling cascades. This allows for highly heterogeneous patterns of NMDAR regulation by cocaine in distinct brain regions and at distinct synapses. The picture is further complicated by findings that cocaine effects on NMDARs are sensitive to the behavioral history of cocaine exposure such as the mode of cocaine administration. This review provides a summary of evidence for cocaine-induced changes in NMDAR expression, cocaine-induced alterations in NMDAR function, and cocaine effects on NMDAR control of intracellular signaling cascades.
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11
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Fakira AK, Portugal GS, Carusillo B, Melyan Z, Morón JA. Increased small conductance calcium-activated potassium type 2 channel-mediated negative feedback on N-methyl-D-aspartate receptors impairs synaptic plasticity following context-dependent sensitization to morphine. Biol Psychiatry 2014; 75:105-14. [PMID: 23735878 PMCID: PMC3992971 DOI: 10.1016/j.biopsych.2013.04.026] [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: 11/28/2012] [Revised: 04/17/2013] [Accepted: 04/29/2013] [Indexed: 12/21/2022]
Abstract
BACKGROUND Hippocampal long-term potentiation (LTP) is impaired following repeated morphine administration paired with a novel context. This procedure produces locomotor sensitization that can be abolished by blocking calcium (Ca(2+))-permeable alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) in the hippocampus. However, the mechanisms underlying LTP impairment remain unclear. Here, we investigate the role of N-methyl-D-aspartate receptors (NMDARs), AMPARs, and small conductance Ca(2+)-activated potassium type 2 (SK2) channels in LTP induction after context-dependent sensitization to morphine. METHODS Mice were treated with saline or escalating doses of morphine (5, 8, 10, and 15 mg/kg) every 12 hours in a locomotor activity chamber and a challenge dose of 5 mg/kg morphine was given 1 week later. After the challenge, the hippocampi were removed to assay phosphatase 2A (PP2A) activity, NMDAR, and SK2 channel synaptic expression or to perform electrophysiological recordings. RESULTS Impaired hippocampal LTP, which accompanied morphine-induced context-dependent sensitization, could not be restored by blocking Ca(2+)-permeable AMPARs. Context-dependent sensitization to morphine altered hippocampal NMDAR subunit composition and enhanced the SK2 channel-mediated negative feedback on NMDAR. Increased PP2A activity observed following context-dependent sensitization suggests that the potentiated SK2 channel effect on NMDAR was mediated by increased SK2 sensitivity to Ca(2+). Finally, inhibition of SK2 channel or PP2A activity restored LTP. CONCLUSIONS Our studies demonstrate that the SK2 channel-NMDAR feedback loop plays a role in opiate-induced impairment of hippocampal plasticity and that the positive modulation of SK2 channels occurs via increases in PP2A activity. This provides further evidence that small conductance Ca(2+)-activated potassium channels play a role in drug-induced plasticity.
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Affiliation(s)
- Amanda K Fakira
- Department of Anesthesiology, College of Physicians and Surgeons, Columbia University Medical Center, New York, New York
| | - George S Portugal
- Department of Anesthesiology, College of Physicians and Surgeons, Columbia University Medical Center, New York, New York
| | - Brianna Carusillo
- Department of Anesthesiology, College of Physicians and Surgeons, Columbia University Medical Center, New York, New York
| | - Zare Melyan
- Department of Anesthesiology, College of Physicians and Surgeons, Columbia University Medical Center, New York, New York
| | - Jose A Morón
- Department of Anesthesiology, College of Physicians and Surgeons, Columbia University Medical Center, New York, New York.
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Zhao B, Zhu Y, Wang W, Cui HM, Wang YP, Lai JH. Analysis of variations in the glutamate receptor, N-methyl D-aspartate 2A (GRIN2A) gene reveals their relative importance as genetic susceptibility factors for heroin addiction. PLoS One 2013; 8:e70817. [PMID: 23940648 PMCID: PMC3733659 DOI: 10.1371/journal.pone.0070817] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 06/23/2013] [Indexed: 12/12/2022] Open
Abstract
The glutamate receptor, N-methyl D-aspartate 2A (GRIN2A) gene that encodes the 2A subunit of the N-methyl D-aspartate (NMDA) receptor was recently shown to be involved in the development of opiate addiction. Genetic polymorphisms in GRIN2A have a plausible role in modulating the risk of heroin addiction. An association of GRIN2A single-nucleotide polymorphisms (SNPs) with heroin addiction was found earlier in African Americans. To identify markers that contribute to the genetic susceptibility to heroin addiction, we examined the potential association between heroin addiction and forty polymorphisms of the GRIN2A gene using the MassARRAY system and GeneScan in this study. The frequency of the (GT)26 repeats (rs3219790) in the heroin addiction group was significantly higher than that in the control group (χ2 = 5.360, P = 0.021). The allele frequencies of three polymorphisms (rs1102972, rs1650420, and rs3104703 in intron 3) were strongly associated with heroin addiction (P<0.001, 0.0002, and <0.001, after Bonferroni correction). Three additional SNPs from the same intron (rs1071502, rs6497730, and rs1070487) had nominally significant P values for association (P<0.05), but did not pass the threshold value. Haplotype analysis revealed that the G-C-T-C-C-T-A (block 6) and T-T (block 10) haplotypes of the GRIN2A gene displayed a protective effect (P = <0.001 and 0.003). These findings point to a role for GRIN2A polymorphisms in heroin addiction among the Han Chinese from Shaanxi province, and may be informative for future genetic or neurobiological studies on heroin addiction.
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Affiliation(s)
- Bin Zhao
- College of Forensic Science, Xi’an Jiaotong University, Key Laboratory of Ministry of Public Health for Forensic Science, Xi’an, Shaanxi, PR China
| | - Yongsheng Zhu
- College of Forensic Science, Xi’an Jiaotong University, Key Laboratory of Ministry of Public Health for Forensic Science, Xi’an, Shaanxi, PR China
- Department of Medical Genetics and Cell Biology, Ningxia Medical University, Key Laboratory of Fertility Preservation and Maintenance, Ningxia Medical University, Ministry of Education, Ningxia, Yinchuan, PR China
| | - Wei Wang
- College of Forensic Science, Xi’an Jiaotong University, Key Laboratory of Ministry of Public Health for Forensic Science, Xi’an, Shaanxi, PR China
| | - Hai-min Cui
- College of Forensic Science, Xi’an Jiaotong University, Key Laboratory of Ministry of Public Health for Forensic Science, Xi’an, Shaanxi, PR China
| | - Yun-peng Wang
- College of Forensic Science, Xi’an Jiaotong University, Key Laboratory of Ministry of Public Health for Forensic Science, Xi’an, Shaanxi, PR China
| | - Jiang-hua Lai
- College of Forensic Science, Xi’an Jiaotong University, Key Laboratory of Ministry of Public Health for Forensic Science, Xi’an, Shaanxi, PR China
- Key Laboratory of Environment and Genes Related to Diseases, Xi’an Jiaotong University, Ministry of Education, Xi’an, Shaanxi, PR China
- * E-mail:
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Vélez-Hernández ME, Vázquez-Torres R, Velasquez-Martinez MC, Jiménez L, Báez F, Sacktor TC, Jiménez-Rivera CA. Inhibition of Protein kinase Mzeta (PKMζ) in the mesolimbic system alters cocaine sensitization in rats. JOURNAL OF DRUG AND ALCOHOL RESEARCH 2013; 2:235669. [PMID: 24729912 PMCID: PMC3980506 DOI: 10.4303/jdar/235669] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Chronic cocaine use produces long-lasting changes in reward circuits that may underlie the transition from casual to compulsive patterns of drug use. Although strong neuroadaptations within the mesocorticolimbic system are known to occur, the specific role of these drug-induced plasticities on sensitization remains to be elucidated. Here we investigate whether PKMζ, a protein involved in maintaining long-term potentiation (LTP), plays a role in these cocaine-induced changes in synaptic strengthening. We performed whole-cell voltage clamp recordings of putative ventral tegmental area (VTA) dopamine (DA) cells 24 hours after five days of 15 mg/kg i.p. cocaine or isovolumetric saline injections. We observed that superfusion of 5µM ZIP (PKMζ inhibitory peptide) decreased AMPA currents and AMPA/NMDA ratios only in cocaine sensitized rats. In vivo ZIP microinfusions (10 nmol) into the VTA after cocaine sensitization decreased locomotor activity on a subsequent cocaine challenge only if given ZIP is given before the withdrawal period. On the other hand, ZIP microinfusions into the nucleus accumbens (NAc) core after a seven days withdrawal period disrupt the expression of locomotor sensitization. The present data provide a potentially relevant region, and time-specific PKMζ-dependent brain mechanism that enables sensitization. Our results support the vision that addiction involves a pathological learning process. They imply that if this synaptic strengthening is reversed, changes in the behavioral response may also be overturned.
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Affiliation(s)
- María E. Vélez-Hernández
- Department of Physiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
| | - Rafael Vázquez-Torres
- Department of Physiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
| | | | - Lincoln Jiménez
- Section of Neurological Surgery, Department of Neurosurgery, Medical Sciences Campus, San Juan, Puerto Rico
| | - Frankie Báez
- Section of Neurological Surgery, Department of Neurosurgery, Medical Sciences Campus, San Juan, Puerto Rico
| | - Todd C. Sacktor
- Departments of Physiology, Pharmacology and Neurology, SUNY Downstate Medical Center, New York
| | - Carlos A. Jiménez-Rivera
- Department of Physiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico
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14
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Drug-evoked synaptic plasticity: beyond metaplasticity. Curr Opin Neurobiol 2013; 23:553-8. [PMID: 23571119 DOI: 10.1016/j.conb.2013.03.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 02/28/2013] [Accepted: 03/08/2013] [Indexed: 01/06/2023]
Abstract
Addictive drugs such as cocaine induce synaptic plasticity in the ventral tegmental area and its projection areas, which may represent the cellular correlate of an addiction trace. Cocaine induces changes in excitatory transmission primarily in the VTA, which persists for days after a single exposure. These initial alterations in synaptic transmission represent a metaplasticity that is permissive for late stages of remodeling throughout the mesocorticolimbic circuitry, specifically in the NAc. Specific synaptic and cellular changes in the NAc persist following prolonged exposure to cocaine, and this remodeling may contribute to altered behavior. By manipulating synaptic activity in the NAc, it may be possible to reverse pathological synaptic transmission and its associated abnormal behavior following exposure to addictive drugs.
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Madsen HB, Brown RM, Lawrence AJ. Neuroplasticity in addiction: cellular and transcriptional perspectives. Front Mol Neurosci 2012; 5:99. [PMID: 23162427 PMCID: PMC3495339 DOI: 10.3389/fnmol.2012.00099] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Accepted: 10/20/2012] [Indexed: 12/17/2022] Open
Abstract
Drug addiction is a chronic, relapsing brain disorder which consists of compulsive patterns of drug-seeking and taking that occurs at the expense of other activities. The transition from casual to compulsive drug use and the enduring propensity to relapse is thought to be underpinned by long-lasting neuroadaptations in specific brain circuitry, analogous to those that underlie long-term memory formation. Research spanning the last two decades has made great progress in identifying cellular and molecular mechanisms that contribute to drug-induced changes in plasticity and behavior. Alterations in synaptic transmission within the mesocorticolimbic and corticostriatal pathways, and changes in the transcriptional potential of cells by epigenetic mechanisms are two important means by which drugs of abuse can induce lasting changes in behavior. In this review we provide a summary of more recent research that has furthered our understanding of drug-induced neuroplastic changes both at the level of the synapse, and on a transcriptional level, and how these changes may relate to the human disease of addiction.
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Affiliation(s)
- Heather B Madsen
- Addiction Neuroscience Laboratory, Florey Institute of Neuroscience and Mental Health Parkville, VIC, Australia
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16
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Pharmacotherapeutics directed at deficiencies associated with cocaine dependence: focus on dopamine, norepinephrine and glutamate. Pharmacol Ther 2012; 134:260-77. [PMID: 22327234 DOI: 10.1016/j.pharmthera.2012.01.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 01/19/2012] [Indexed: 11/20/2022]
Abstract
Much effort has been devoted to research focused on pharmacotherapies for cocaine dependence yet there are no FDA-approved medications for this brain disease. Preclinical models have been essential to defining the central and peripheral effects produced by cocaine. Recent evidence suggests that cocaine exerts its reinforcing effects by acting on multiple neurotransmitter systems within mesocorticolimibic circuitry. Imaging studies in cocaine-dependent individuals have identified deficiencies in dopaminergic signaling primarily localized to corticolimbic areas. In addition to dysregulated striatal dopamine, norepinephrine and glutamate are also altered in cocaine dependence. In this review, we present these brain abnormalities as therapeutic targets for the treatment of cocaine dependence. We then survey promising medications that exert their therapeutic effects by presumably ameliorating these brain deficiencies. Correcting neurochemical deficits in cocaine-dependent individuals improves memory and impulse control, and reduces drug craving that may decrease cocaine use. We hypothesize that using medications aimed at reversing known neurochemical imbalances is likely to be more productive than current approaches. This view is also consistent with treatment paradigms used in neuropsychiatry and general medicine.
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17
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Michaeli A, Matzner H, Poltyrev T, Yaka R. Modifications of the input currents on VTA dopamine neurons following acute versus chronic cocaine exposure. Neuropharmacology 2011; 62:1834-40. [PMID: 22197515 DOI: 10.1016/j.neuropharm.2011.12.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 11/30/2011] [Accepted: 12/07/2011] [Indexed: 10/14/2022]
Abstract
Excitatory synapses on dopamine (DA) neurons in the ventral tegmental area (VTA) are modulated following exposure to various addictive drugs, including cocaine. Previously we have shown that cocaine affects GABA(A) receptor (GABA(A)R)-mediated neurotransmission in VTA DA neurons. This finding led us to reexamine the modulation of the excitatory synapse on these neurons in response to cocaine exposure, while the activity of GABA(A)R is uninterrupted. Using rat brain slices, evoked post synaptic currents (ePSC) were monitored and inhibitors of NMDA receptor (NMDAR) and AMPA receptor (AMPAR) were gradually added to inhibitors-free bath solution. Modifications in the efficacy of the excitatory synapses were evaluated by comparing AMPAR-mediated and NMDAR-mediated currents (AMPA/NMDA ratio). The lack of GABA(A)R inhibitors enabled us to examine parallel changes in the relation between GABA(A)R-mediated and NMDAR-mediated currents (GABA(A)/NMDA ratio). First, we found that AMPA/NMDA ratio measured under complete availability of GABA(A)R, is significantly higher than the ratio measured under GABA(A)R blockade. In addition, GABA(A)/NMDA ratio, but not AMPA/NMDA ratio, is augmented a few hours following in vitro acute cocaine exposure. When measured 24 h after in vivo single cocaine injection, no change in GABA(A)/NMDA ratio was observed, however, the AMPA/NMDA ratio was found to be significantly higher. Finally, a decrease in both ratios was detected in rats repeatedly injected with cocaine. Taken together, these results lead to a better understanding of the means by which cocaine modifies synaptic inputs on VTA DA neurons. The parallel changes in GABA(A)/NMDA ratio may suggest an interaction between inhibitory and excitatory neural systems.
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Affiliation(s)
- Avner Michaeli
- Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
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18
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Ness V, Arning L, Niesert HE, Stüttgen MC, Epplen JT, Beste C. Variations in the GRIN2B gene are associated with risky decision-making. Neuropharmacology 2011; 61:950-6. [PMID: 21749895 DOI: 10.1016/j.neuropharm.2011.06.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 06/21/2011] [Accepted: 06/23/2011] [Indexed: 10/18/2022]
Abstract
The dopaminergic system is known to modulate decision-making. As N-methyl-D-aspartate (NMDA) receptors strongly influence dopaminergic function, it is conceivable that the glutamatergic system is also involved in decision-making. We examined whether polymorphisms in the N-methyl-d-aspartate receptor 2B subunit gene (GRIN2B) influence decision-making using the Iowa Gambling Task (IGT). In total, 245 (n = 245, 127 female) healthy German students were included in the analysis. Two synonymous SNPs in exon 13, rs1806191 (H1178H) and rs1806201 (T888T) showed the strongest association with aspects of IGT performance. Females with a CC allele in rs1806201 made less use both of a win-stay strategy and demonstrated more exploratory behaviour during task execution. For rs1806191, we found a strong additive effect in usage of a win-stay strategy. This, partly sex-dependent, correlation of the win-stay/lose-shift behaviour with GRIN2B genotypes suggests that healthy individuals with certain GRIN2B variations respond differently to ambiguous conditions, possibly by altered perception of wins and losses. These findings underline the necessity to integrate the glutamatergic system when examining decision-making processes.
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Affiliation(s)
- Vanessa Ness
- Institute of Cognitive Neuroscience, Department of Biopsychology, Ruhr-University Bochum, Bochum, Germany.
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Steketee JD, Kalivas PW. Drug wanting: behavioral sensitization and relapse to drug-seeking behavior. Pharmacol Rev 2011; 63:348-65. [PMID: 21490129 DOI: 10.1124/pr.109.001933] [Citation(s) in RCA: 451] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Repeated exposure to drugs of abuse enhances the motor-stimulant response to these drugs, a phenomenon termed behavioral sensitization. Animals that are extinguished from self-administration training readily relapse to drug, conditioned cue, or stress priming. The involvement of sensitization in reinstated drug-seeking behavior remains controversial. This review describes sensitization and reinstated drug seeking as behavioral events, and the neural circuitry, neurochemistry, and neuropharmacology underlying both behavioral models will be described, compared, and contrasted. It seems that although sensitization and reinstatement involve overlapping circuitry and neurotransmitter and receptor systems, the role of sensitization in reinstatement remains ill-defined. Nevertheless, it is argued that sensitization remains a useful model for determining the neural basis of addiction, and an example is provided in which data from sensitization studies led to potential pharmacotherapies that have been tested in animal models of relapse and in human addicts.
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Affiliation(s)
- Jeffery D Steketee
- Department of Pharmacology, University of Tennessee Health Science Center, 874 Union Avenue, Memphis, TN 38163, USA.
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20
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Zellner MR, Ranaldi R. How conditioned stimuli acquire the ability to activate VTA dopamine cells: a proposed neurobiological component of reward-related learning. Neurosci Biobehav Rev 2009; 34:769-80. [PMID: 19914285 DOI: 10.1016/j.neubiorev.2009.11.011] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 11/09/2009] [Accepted: 11/10/2009] [Indexed: 02/04/2023]
Abstract
The ability to learn about conditioned stimuli (CS) associated with rewards is a crucial adaptive mechanism. Activity in the mesocorticolimbic dopamine (DA) system, as well as in the ventral tegmental area (VTA), is correlated with responding to and learning about CSs. The mechanism by which VTA neurons become activated by signals associated with conditioned stimuli is not fully understood. Our model suggests that NMDA receptor stimulation in the VTA allows originally weak glutamate signals carrying information about environmental stimuli, coincident with strong excitation correlated with primary rewards, to be strengthened and thereby acquire the ability to activate VTA neurons in themselves, producing approach. Furthermore, once synaptic strengthening occurs, the model suggests that NMDA receptor stimulation in VTA is not necessary for the expression of reward-related learning. In this review we survey evidence that VTA cells respond to cues associated with primary rewards, that this responding is acquired, and that the VTA possesses the attributes to function as a site of integration of signals of primary and conditioned stimuli.
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Affiliation(s)
- Margaret R Zellner
- Laboratory of Neurobiology & Behavior, The Rockefeller University, New York, NY, United States
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