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Wolter M, Lapointe T, Baidoo N, Mitchnick KA, Wideman C, Winters BD, Leri F. Double dissociation of perirhinal nicotinic acetylcholine receptors and dopamine D2 receptors in modulation of object memory consolidation by nicotine, cocaine and their conditioned stimuli. Eur Neuropsychopharmacol 2023; 72:50-59. [PMID: 37086715 DOI: 10.1016/j.euroneuro.2023.04.002] [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: 11/30/2022] [Revised: 03/27/2023] [Accepted: 04/03/2023] [Indexed: 04/24/2023]
Abstract
There are indications that drug conditioned stimuli (CS) may activate neurochemical systems of memory modulation that are activated by the drugs themselves. To directly test this hypothesis, a cholinergic nicotinic receptor antagonist (mecamylamine; MEC: 0, 10 or 30 µg/side) and a dopamine D2 receptor antagonist (l-741,626: 0, 0.63, 2.5 µg/side) were infused in the perirhinal cortex (PRh) to block modulation of object recognition memory consolidation induced by 0.4 mg/kg nicotine, 20 mg/kg cocaine, or their CSs. To establish these CSs, male Sprague-Dawley rats were confined for 2 h in a chamber, the CS+, after injections of 0.4 mg/kg nicotine, or 20 mg/kg cocaine, and in another chamber, the CS-, after injections of vehicle. This was repeated over 10 days (5 drug/CS+ and 5 vehicle/CS- pairings in total). It was found that the memory enhancing action of post-sample nicotine was blocked by intra-PRh infusions of both MEC doses, and 30 µg/side MEC also blocked the memory enhancing action of the nicotine CS. Interestingly, intra-PRh MEC did not block the memory enhancing effect of cocaine, nor that of the cocaine CS. In contrast, the memory enhancing action of post-sample cocaine administration was blocked by both l-741,626 doses, and 2.5 µg/side also blocked the effect of the cocaine CS, but not the memory effects of nicotine or of the nicotine CS. This functional double dissociation strongly indicates that drug CSs modulate memory consolidation by activating neural systems that are activated by the drugs themselves.
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Affiliation(s)
- Michael Wolter
- Department of Psychology & Neuroscience Specialization, University of Guelph, ON, N1G 2W1 Canada
| | - Thomas Lapointe
- Department of Psychology & Neuroscience Specialization, University of Guelph, ON, N1G 2W1 Canada
| | - Nana Baidoo
- Department of Psychology & Neuroscience Specialization, University of Guelph, ON, N1G 2W1 Canada
| | | | - Cassidy Wideman
- Department of Psychology & Neuroscience Specialization, University of Guelph, ON, N1G 2W1 Canada
| | - Boyer D Winters
- Department of Psychology & Neuroscience Specialization, University of Guelph, ON, N1G 2W1 Canada
| | - Francesco Leri
- Department of Psychology & Neuroscience Specialization, University of Guelph, ON, N1G 2W1 Canada.
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Wolter M, Huff AE, Baidoo N, Jardine KH, Pulles Z, Winters BD, Leri F. Modulation of object memory consolidation by heroin and heroin-conditioned stimuli: Role of opioid and noradrenergic systems. Eur Neuropsychopharmacol 2020; 33:146-157. [PMID: 32067860 DOI: 10.1016/j.euroneuro.2020.01.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/21/2019] [Accepted: 01/22/2020] [Indexed: 11/18/2022]
Abstract
There is recent evidence that cocaine, nicotine, and their conditioned stimuli have the ability to enhance memory consolidation. The present study compared the effects of post-training heroin and of a heroin contextual conditioned stimulus (CS+) on consolidation of object recognition memory and investigated the roles of opioid and beta-adrenergic receptors in heroin/CS+ memory modulation by co-administering the respective antagonists, naltrexone (NTX) and propranolol (PRO). Three experiments were performed in male Sprague-Dawley rats demonstrating that immediate, but not delayed, post-sample exposure to heroin (0.3, 1 mg/kg), or exposure (30 min) to a contextual CS+ paired with 1 mg/kg heroin (5 pairings, each 120 min), equally enhanced object memory. Importantly, while the memory enhancing effects of 1 mg/kg heroin and of the contextual CS+ were not altered by post-training co-administration of 3 mg/kg naltrexone, they were blocked by post-training co-administration of 10 mg/kg propranolol. Taken together, these data suggest that a context paired with heroin shares the memory enhancing effect of heroin itself and that these unconditioned and conditioned drug stimuli may modulate memory through the activation of beta-noradrenergic receptors.
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Affiliation(s)
- Michael Wolter
- Department of Psychology & Collaborative Neuroscience Program, University of Guelph, 50 Stone Road East, N1G 2W1 Guelph, ON, Canada
| | - Andrew E Huff
- Department of Psychology & Collaborative Neuroscience Program, University of Guelph, 50 Stone Road East, N1G 2W1 Guelph, ON, Canada
| | - Nana Baidoo
- Department of Psychology & Collaborative Neuroscience Program, University of Guelph, 50 Stone Road East, N1G 2W1 Guelph, ON, Canada
| | - Kristen H Jardine
- Department of Psychology & Collaborative Neuroscience Program, University of Guelph, 50 Stone Road East, N1G 2W1 Guelph, ON, Canada
| | - Zoey Pulles
- Department of Psychology & Collaborative Neuroscience Program, University of Guelph, 50 Stone Road East, N1G 2W1 Guelph, ON, Canada
| | - Boyer D Winters
- Department of Psychology & Collaborative Neuroscience Program, University of Guelph, 50 Stone Road East, N1G 2W1 Guelph, ON, Canada
| | - Francesco Leri
- Department of Psychology & Collaborative Neuroscience Program, University of Guelph, 50 Stone Road East, N1G 2W1 Guelph, ON, Canada.
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Wolter M, Huff E, Speigel T, Winters BD, Leri F. Cocaine, nicotine, and their conditioned contexts enhance consolidation of object memory in rats. ACTA ACUST UNITED AC 2019; 26:46-55. [PMID: 30651377 PMCID: PMC6340119 DOI: 10.1101/lm.048579.118] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/18/2018] [Indexed: 12/28/2022]
Abstract
To test the hypothesis that drugs of abuse and their conditioned stimuli (CSs) enhance memory consolidation, the effects of post-training exposure to cocaine and nicotine were compared to the effects of post-training exposure to contextual stimuli that were paired with the effects of these drugs. Using the object recognition (OR) task, it was first demonstrated that both 10 and 20 mg/kg cocaine, and 0.2 and 0.4 mg/kg nicotine, enhanced recognition memory when administered immediately after, but not 6 h after the sample phase. To establish the drug CSs, rats were confined for 2 h in a chamber (the CS+) after injections of 20 mg/kg cocaine, or 0.4 mg/kg nicotine, and in another chamber (the CS−) after injections of vehicle. This was repeated over 10 d (5 drug/CS+ and 5 vehicle/CS− pairings in total). At the end of this conditioning period, when tested in a drug-free state, rats displayed conditioned hyperactivity in the CS+ relative to the CS−. More important, immediate, but not delayed, post-sample exposure to the cocaine CS+, or nicotine CS+, enhanced OR memory. Therefore, this study reports for the first time that contextual stimuli paired with cocaine and nicotine, like the drugs themselves, have the ability to enhance memory consolidation.
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Affiliation(s)
- Michael Wolter
- Department of Psychology and Collaborative Program in Neuroscience, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Ethan Huff
- Department of Psychology and Collaborative Program in Neuroscience, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Talia Speigel
- Department of Psychology and Collaborative Program in Neuroscience, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Boyer D Winters
- Department of Psychology and Collaborative Program in Neuroscience, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Francesco Leri
- Department of Psychology and Collaborative Program in Neuroscience, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Differential modulatory effects of cocaine on marmoset monkey recognition memory. PROGRESS IN BRAIN RESEARCH 2017; 235:155-176. [PMID: 29054287 DOI: 10.1016/bs.pbr.2017.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Acute and repeated exposure to cocaine alters the cognitive performance of humans and animals. How each administration schedule affects the same memory task has yet to be properly established in nonhuman primates. Therefore, we assessed the performance of marmoset monkeys in a spontaneous object-location (SOL) recognition memory task after acute and repeated exposure to cocaine (COC; 5mg/kg, ip). Two identical neutral stimuli were explored on the 10-min sample trial, after which preferential exploration of the displaced vs the stationary object was analyzed on the 10-min test trial. For the acute treatment, cocaine was given immediately after the sample presentation, and spatial recognition was then tested after a 24-h interval. For the repeated exposure schedule, daily cocaine injections were given on 7 consecutive days. After a 7-day drug-free period, the SOL task was carried out with a 10-min intertrial interval. When given acutely postsample, COC improved the marmosets' recognition memory, whereas it had a detrimental effect after the repeated exposure. Thus, depending on the administration schedule, COC exerted opposing effects on the marmosets' ability to recognize spatial changes. This agrees with recent studies in rodents and the recognition impairment seen in human addicts. Further studies related to the effects of cocaine's acute×prior drug history on the same cognitive domain are warranted.
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Post-training cocaine administration facilitates habit learning and requires the infralimbic cortex and dorsolateral striatum. Neurobiol Learn Mem 2014; 118:105-12. [PMID: 25460040 DOI: 10.1016/j.nlm.2014.11.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 10/01/2014] [Accepted: 11/07/2014] [Indexed: 01/17/2023]
Abstract
Human drug addiction is a complex disorder, in which exogenous substances are able to recruit and maintain behaviors involved in drug taking. Many drugs that are addictive in humans are able to act on natural brain systems for learning and memory, and while many memory systems may be affected by addictive drugs, work with operant tasks has shown that addictive drugs (e.g. cocaine and alcohol) are particularly effective in recruiting habit learning systems, compared to natural rewards. It is currently unknown if the ability of addictive drugs to facilitate habit learning depends on a direct action on habit learning systems in the brain, versus the rewarding properties of drug administration. To differentiate between these options, rats were trained to perform two actions (lever pressing), each of which was rewarded with a different natural reward. After acquiring the behavior, rats received three training sessions which were followed by post-training injections of saline or cocaine (5 or 10mg/kg, i.p.). Using sensory-specific satiety, extinction tests revealed that lever pressing for actions which were paired with saline were sensitive to devaluation (typical of goal-directed behaviors) while actions which were paired with cocaine were not sensitive to devaluation (typical of habitual behaviors). Lesions of the infralimbic or dorsolateral striatum were able to block the action of post-training cocaine injections. These data indicate that, within individual rats, cocaine injections facilitate the transition of behavior to habitual control for actions that have been recently performed, without a general facilitation of habit learning, and that this action of cocaine requires brain areas that are critical for learning natural habits.
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Drugs of abuse as memory modulators: a study of cocaine in rats. Psychopharmacology (Berl) 2014; 231:2339-48. [PMID: 24337026 DOI: 10.1007/s00213-013-3390-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 11/29/2013] [Indexed: 01/22/2023]
Abstract
RATIONALE It has been proposed that drugs of abuse reinforce behavior partly, or wholly, because they facilitate learning by enhancing memory consolidation. Cocaine can clearly serve as a reinforcer, but its effect on learning has not been fully characterized. OBJECTIVES To explore the effects of different regimens of pre- and post-training cocaine administration on win-stay and object learning. METHODS Cocaine naïve and cocaine pre-exposed (30 mg/kg/day, × 5 days followed by 7 days drug-free) male Sprague-Dawley rats received cocaine (0, 1, 2.5, 7.5, or 20 mg/kg, i.p.) immediately following training on a win-stay task in a radial maze or following the sample phase of an object learning task. Win-stay performance was also assessed in tests of extinction and after a set shift. RESULTS Post-training cocaine did not improve accuracy on the win-stay task and produced performance deficits at 20 mg/kg. These deficits were attenuated by prior cocaine exposure. There was indirect evidence of facilitated learning in extinction and set shift tests, but the effective dosage was different (2.5 and 7.5 mg/kg, respectively). Post-training cocaine produced dose-dependent improvements in object learning. CONCLUSION Post-training cocaine administration can facilitate learning, but this effect is highly dependent on the dose and the type of task employed.
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Hołuj M, Bisaga A, Popik P. Conditioned rewarding effects of morphine and methadone in mice pre-exposed to cocaine. Pharmacol Rep 2013; 65:1176-84. [DOI: 10.1016/s1734-1140(13)71475-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/13/2013] [Indexed: 11/16/2022]
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Paris JJ, Reilley KJ, McLaughlin JP. Kappa Opioid Receptor-Mediated Disruption of Novel Object Recognition: Relevance for Psychostimulant Treatment. ACTA ACUST UNITED AC 2011; S4. [PMID: 22900234 DOI: 10.4172/2155-6105.s4-007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Kappa opioid receptor (KOR) agonists are potentially valuable as therapeutics for the treatment of psychostimulant reward as they suppress dopamine signaling in reward circuitry to repress drug seeking behavior. However, KOR agonists are also associated with sedation and cognitive dysfunction. The extent to which learning and memory disruption or hypolocomotion underlie KOR agonists' role in counteracting the rewarding effects of psychostimulants is of interest. C57BL/6J mice were pretreated with vehicle (saline, 0.9%), the KOR agonist (trans)-3,4-dichloro-N-methyl-N-[2-(1- pyrrolidinyl)-cyclohexyl] benzeneacetamide (U50,488), or the peripherally-restricted agonist D-Phe-D-Phe-D-lle-D-Arg- NH(2) (ffir-NH(2)), through central (i.c.v.) or peripheral (i.p.) routes of administration. Locomotor activity was assessed via activity monitoring chambers and rotorod. Cognitive performance was assessed in a novel object recognition task. Prolonged hypolocomotion was observed following administration of 1.0 and 10.0, but not 0.3 mg/kg U50,488. Central, but not peripheral, administration of ffir-NH(2) (a KOR agonist that does not cross the blood-brain barrier) also reduced motor behavior. Systemic pretreatment with the low dose of U50,488 (0.3 mg/kg, i.p.) significantly impaired performance in the novel object recognition task. Likewise, ffir-NH(2) significantly reduced novel object recognition after central (i.c.v.), but not peripheral (i.p.), administration. U50,488- and ffir-NH(2)-mediated deficits in novel object recognition were prevented by pretreatment with KOR antagonists. Cocaine-induced conditioned place preference was subsequently assessed and was reduced by pretreatment with U50,488 (0.3 mg/kg, i.p.). Together, these results suggest that the activation of centrally-located kappa opioid receptors may induce cognitive and mnemonic disruption independent of hypolocomotor effects which may contribute to the KOR-mediated suppression of psychostimulant reward.
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Affiliation(s)
- Jason J Paris
- Torrey Pines Institute for Molecular Studies, 11350 SW Village Parkway, Port St. Lucie, FL 34987, USA
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Perez MF, Gabach LA, Almiron RS, Carlini VP, De Barioglio SR, Ramirez OA. Different chronic cocaine administration protocols induce changes on dentate gyrus plasticity and hippocampal dependent behavior. Synapse 2010; 64:742-53. [PMID: 20698030 DOI: 10.1002/syn.20788] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hippocampus is a limbic structure that participates in learning and memory formation. Specifically the dentate gyrus has been described as a hippocampal subregion with high rates of plasticity and it is targeted by different psychoactive drugs modulating synaptic plasticity. Repeated cocaine administration induces sensitization to the locomotor effects and it is believed that sensitization involves the same mechanisms of drug seeking and relapse. Although, the mechanisms underlying sensitization is not fully understood. In this work we investigated the impact of repeated intraperitoneal administration of cocaine (15 or 20 mg/kg/day along 5 or 15 days respectively; and 15 mg/kg/day along 5 day followed by a challenge dose after three days of withdrawal) on the dentate gyrus synaptic plasticity, differentiating between sensitized and nonsensitized rats. Furthermore, we correlated changes on the hippocampal synaptic plasticity to memory retention. Our results revealed that the prevalence of cocaine sensitization (around 50%) was identical in all protocols used. The results found in the threshold to generate LTP were similar for all protocols used, being the threshold values cocaine-treated groups (sensitized and nonsensitized) significantly reduced compared to controls, observing the highest reduction in the sensitized group. Moreover, we observed a facilitated retention of recent memory formation only in sensitized animals the nonsensitized subjects remained at the control levels. In conclusion, sensitization to cocaine generates a high efficiency of hippocampal synaptic plasticity that may underlie the aberrant engagement of learning processes occurred during drug addiction.
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Affiliation(s)
- M F Perez
- IFEC, Conicet, Departamento de Farmacologia, Facultad de Ciencias Quimicas, Unc, Haya de la Torre Y Medina Allende, 5000, Cordoba, Argentina.
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Cobos EJ, Entrena JM, Nieto FR, Cendán CM, Del Pozo E. Pharmacology and therapeutic potential of sigma(1) receptor ligands. Curr Neuropharmacol 2010; 6:344-66. [PMID: 19587856 PMCID: PMC2701284 DOI: 10.2174/157015908787386113] [Citation(s) in RCA: 287] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 07/18/2008] [Accepted: 07/09/2008] [Indexed: 11/22/2022] Open
Abstract
Sigma (σ) receptors, initially described as a subtype of opioid receptors, are now considered unique receptors. Pharmacological studies have distinguished two types of σ receptors, termed σ1 and σ2. Of these two subtypes, the σ1 receptor has been cloned in humans and rodents, and its amino acid sequence shows no homology with other mammalian proteins. Several psychoactive drugs show high to moderate affinity for σ1 receptors, including the antipsychotic haloperidol, the antidepressant drugs fluvoxamine and sertraline, and the psychostimulants cocaine and methamphetamine; in addition, the anticonvulsant drug phenytoin allosterically modulates σ1 receptors. Certain neurosteroids are known to interact with σ1 receptors, and have been proposed to be their endogenous ligands. These receptors are located in the plasma membrane and in subcellular membranes, particularly in the endoplasmic reticulum, where they play a modulatory role in intracellular Ca2+ signaling. Sigma1 receptors also play a modulatory role in the activity of some ion channels and in several neurotransmitter systems, mainly in glutamatergic neurotransmission. In accordance with their widespread modulatory role, σ1 receptor ligands have been proposed to be useful in several therapeutic fields such as amnesic and cognitive deficits, depression and anxiety, schizophrenia, analgesia, and against some effects of drugs of abuse (such as cocaine and methamphetamine). In this review we provide an overview of the present knowledge of σ1 receptors, focussing on σ1 ligand neuropharmacology and the role of σ1 receptors in behavioral animal studies, which have contributed greatly to the potential therapeutic applications of σ1 ligands.
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Affiliation(s)
- E J Cobos
- Department of Pharmacology and Institute of Neuroscience, Faculty of Medicine, University of Granada, Granada, Spain
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Sticht M, Mitsubata J, Tucci M, Leri F. Reacquisition of heroin and cocaine place preference involves a memory consolidation process sensitive to systemic and intra-ventral tegmental area naloxone. Neurobiol Learn Mem 2009; 93:248-60. [PMID: 19857583 DOI: 10.1016/j.nlm.2009.10.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2009] [Revised: 09/29/2009] [Accepted: 10/20/2009] [Indexed: 02/08/2023]
Abstract
To investigate the effect of naloxone on a putative memory consolidation process underlying reacquisition of heroin and cocaine conditioned place preference, four studies were conducted in male Sprague-Dawley rats using a common procedure involving: place conditioning (0.3 or 1mg/kg heroin or 20mg/kg cocaine; x4 sessions), extinction (vehiclex4 sessions), and reconditioning (0 or 1mg/kg heroin or 20mg/kg cocaine; x1 session). Systemic naloxone injections (0, 1 and 3mg/kg) or bilateral intra-ventral tegmental area (VTA) naloxone methiodide infusions (2 nmol in 0.5 microl x side) were administered at different times following reconditioning. Post-reconditioning administration of naloxone dose-dependently blocked, attenuated and had no effect on reacquisition of heroin CPP when administered immediately, 1h and 6h after reconditioning, respectively. The highest dose of naloxone also blocked reacquisition of cocaine CPP, and did not produce a conditioned place aversion in heroin-naïve and heroin pre-treated animals. Post-reconditioning infusions in the VTA, but not in adjacent structures, blocked reacquisition of heroin CPP when administered immediately, but not 6h, after reconditioning. These data suggest that reacquisition of drug-cues associations involves a memory consolidation process sensitive to manipulations of the endogenous opioid system, and indicate that opioid receptors in the VTA may be critically involved in the re-emergence of drug seeking behavior.
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Affiliation(s)
- Martin Sticht
- Department of Psychology, University of Guelph, Guelph, Canada N1G 2W1
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Willuhn I, Steiner H. Skill-memory consolidation in the striatum: critical for late but not early long-term memory and stabilized by cocaine. Behav Brain Res 2008; 199:103-7. [PMID: 18687364 DOI: 10.1016/j.bbr.2008.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Revised: 07/09/2008] [Accepted: 07/10/2008] [Indexed: 10/21/2022]
Abstract
The sensorimotor striatum is important for procedural learning, including skill learning. Our previous findings indicate that this part of the striatum mediates the acquisition of a motor skill in a running-wheel task and that this skill learning is dependent on striatal D1 dopamine receptors. Here, we investigated whether the sensorimotor striatum is also involved in the consolidation of this skill memory and whether this consolidation is modified by the indirect dopamine receptor agonist cocaine. Rats were trained on a running wheel for 2 days (40 min/day) to learn a new motor skill, that is, the ability to control the movement of the wheel. Before each training session, the animals received an injection of vehicle or cocaine (25mg/kg, i.p.). Immediately following the training session, an intrastriatal infusion of 2% lidocaine (1 microl) or a sham infusion were administered. Wheel-skill performance was tested before and repeatedly after the training. Our results show that post-trial intrastriatal infusion of lidocaine disrupted late-stage long-term skill memory (post-training days 6-26), but spared early long-term memory (1 day after the training). Skill consolidation was more susceptible to such disruption in animals that practiced less during the training. Cocaine given pre-trial prevented this post-trial disruption of skill consolidation. These findings indicate that the sensorimotor striatum is critical for the consolidation of late but not early long-term skill memory. Furthermore, cocaine appeared to stabilize motor-memory formation by protecting consolidation processes after the training.
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Affiliation(s)
- Ingo Willuhn
- Department of Cellular and Molecular Pharmacology, Rosalind Franklin University of Medicine and Science/The Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064, USA
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Motor-skill learning in a novel running-wheel task is dependent on D1 dopamine receptors in the striatum. Neuroscience 2008; 153:249-58. [PMID: 18343588 DOI: 10.1016/j.neuroscience.2008.01.041] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Revised: 01/24/2008] [Accepted: 01/28/2008] [Indexed: 01/19/2023]
Abstract
Evidence indicates that dopamine receptors regulate processes of procedural learning in the sensorimotor striatum. Our previous studies revealed that the indirect dopamine receptor agonist cocaine alters motor-skill learning-associated gene regulation in the sensorimotor striatum. Cocaine-induced gene regulation in the striatum is principally mediated by D1 dopamine receptors. We investigated the effects of cocaine and striatal D1 receptor antagonism on motor-skill learning. Rats were trained on a running wheel (40-60 min, 2-5 days) to learn a new motor skill, that is, the ability to control the movement of the wheel. Immediately before each training session, the animals received an injection of vehicle or cocaine (25 mg/kg, i.p.), and/or the D1 receptor antagonist SCH-23390 (0, 3, 10 microg/kg, i.p., or 0, 0.3, 1 microg, intrastriatal via chronically implanted cannula). The animal's ability to control/balance the moving wheel (wheel skill) was tested before and repeatedly after the training. Normal wheel-skill memory lasted for at least 4 weeks. Cocaine administered before the training tended to attenuate skill learning. Systemic administration of SCH-23390 alone also impaired skill learning. However, cocaine given in conjunction with the lower SCH-23390 dose (3 microg/kg) reversed the inhibition of skill learning produced by the D1 receptor antagonist, enabling intact skill performance during the whole post-training period. In contrast, when cocaine was administered with the higher SCH-23390 dose (10 microg/kg), skill performance was normalized 1-6 days after the training, but these rats lost their improved wheel skill by day 18 after the training. Similar effects were produced by SCH-23390 (0.3-1 microg) infused into the striatum. Our results indicate that cocaine interferes with normal motor-skill learning, which seems to be dependent on optimal D1 receptor signaling. Furthermore, our findings demonstrate that D1 receptors in the striatum are critical for consolidation of long-term skill memory.
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Romieu P, Lucas M, Maurice T. Sigma1 receptor ligands and related neuroactive steroids interfere with the cocaine-induced state of memory. Neuropsychopharmacology 2006; 31:1431-43. [PMID: 16132061 DOI: 10.1038/sj.npp.1300885] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The present series of experiments examined the involvement of the sigma(1) receptor and related neuroactive steroids in the memory state induced by a very low dose of cocaine. Using a modified passive avoidance procedure in mice, we examined whether cocaine induces state-dependent (StD) learning. Animals trained and tested with saline or the same dose of cocaine (0.1 or 0.3 mg/kg) showed correct retention, measured using two independent parameters: the retention latency and a ratio between the retention latency and the last training latency. Animals trained with cocaine (0.1 mg/kg) and tested with saline or cocaine (0.03, 0.3 mg/kg), or trained with saline and tested with cocaine, showed altered retention parameters, demonstrating that StD occurred. Therefore, cocaine administered before training produced a chemical state used as an endogenous cue to insure optimal retention. Since sigma(1) receptor activation is an important event during the acquisition of cocaine reward, we tested several sigma(1) ligands and related neurosteroids. The sigma(1) agonist igmesine or antagonist BD1047 failed to produce StD, but modified the cocaine state. Among neuroactive steroids, pregnanolone and allopregnanolone, positive modulators of the gamma-aminobutyric acid type A (GABA(A)) receptor, produced StD. However, steroids also acting as sigma(1) agonists, dehydroepiandrosterone (3beta-hydroxy-5alpha-androsten-17-one (DHEA)), pregnenolone, or antagonist, progesterone, failed to induce StD but modified the cocaine state. Furthermore, optimal retention was observed with mice trained with (igmesine or DHEA)+cocaine and tested with a higher dose of cocaine, or with mice trained with (BD1047 or progesterone)+cocaine and tested with vehicle. This study demonstrated that: (i) low doses of cocaine induce a chemical state/memory trace sustaining StD; (ii) modulation of the sigma(1) receptor activation, although insufficient to provoke StD, modulates the cocaine state; (iii) neuroactive steroids exert a unique role in state-dependent vs state-independent learning, via GABA(A) or sigma(1) receptor modulation, and are able to affect the cocaine-induced mnesic trace at low brain concentrations.
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Affiliation(s)
- Pascal Romieu
- Behavioral Neuropharmacology Group, INSERM U. 336, Institut de Biologie, Montpellier, France
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Quirk PL, Richards RW, Avery DD. Subchronic cocaine produces training paradigm-dependent learning deficits in laboratory rats. Pharmacol Biochem Behav 2001; 68:545-53. [PMID: 11325411 DOI: 10.1016/s0091-3057(01)00462-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The effect of cocaine on spatial learning was investigated by exposing male Sprague-Dawley rats to 0, 20, or 40 mg/kg cocaine prior to and during training on a water maze task. Half the animals were pretrained on cued trials prior to hidden platform trials, while the remaining animals completed hidden platform trials immediately. Escape latencies for all animals improved with training, but pretrained animals located the hidden platform faster than untrained animals (P<.001). Pretraining also decreased the effect of cocaine. In pretrained animals, only the high dose of cocaine caused significant increases in escape latency (P<.001), while in the untrained group the lower dose of cocaine also caused a significant increase (P<.001). On working memory measures, cocaine affected both the pretrained (P<.01) and untrained (P<.001) groups. Dwell ratio measurements indicated unaffected reference memory in both pretrained (P<.001) and untrained (P<.001) animals, and no significant differences were detected among the treatment conditions in either group (P>.05). Thus, while cocaine did not abolish learning, the efficiency with which the task was learned was compromised. However, this effect was reduced by pretraining.
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Affiliation(s)
- P L Quirk
- Department of Psychology, Colorado State University, Fort Collins, CO 80523, USA.
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16
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Haapalinna A, Sirviö J, Lammintausta R. Facilitation of cognitive functions by a specific alpha2-adrenoceptor antagonist, atipamezole. Eur J Pharmacol 1998; 347:29-40. [PMID: 9650845 DOI: 10.1016/s0014-2999(98)00077-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The present experiments investigated the effects of a specific and potent alpha2-adrenoceptor antagonist, atipamezole (as a stimulator of the noradrenergic system) on cognitive performance in rats. Atipamezole enhanced the acquisition of a linear-arm maze test and also improved the choice accuracy of poorly performing rats in a delayed (20 min) three-choice maze test. Furthermore, atipamezole improved the achievement of a one-trial appetite-maze when injected immediately after teaching, thus having an effect on consolidation. Atipamezole clearly impaired the acquisition of the active avoidance test. The present results indicate that stimulation of noradrenergic system by atipamezole improves the performance of animals in tasks assessing relational learning and memory, possibly affecting attention, short-term memory and the speed of information processing. It has also an effect on a consolidation process unrelated to attentional or motivational mechanisms. In a stressful test. stimulation of noradrenaline release leads to impairment of performance.
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Affiliation(s)
- A Haapalinna
- Orion, Orion Pharma, Preclinical R&D, Turku, Finland.
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17
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Castellano C, Cabib S, Puglisi-Allegra S. Psychopharmacology of memory modulation: evidence for multiple interaction among neurotransmitters and hormones. Behav Brain Res 1996; 77:1-21. [PMID: 8762156 DOI: 10.1016/0166-4328(96)00200-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Experimental results are reviewed which indicate that memory storage can be altered by a number of post-training treatments that affect different hormones and neurotransmitters. Moreover, evidence was reported which suggests that the action of treatments effective on memory processes involves interactions among different systems, consistently with the complexity of brain systems. In the last decade, inbred strains have been exploited to investigate the role of neurotransmitter and hormone systems in learning and memory, leading to behavioural and neurochemical correlations based on strain differences that provide unique information on the biological systems underlying behaviour. Research carried out on the inbred strains of mice C57BL/6 (C57) and DBA/2 (DBA), demonstrates that the genetic makeup plays an important role in modulating response to drug administration. Thus, recent results have shown that in C57 mice, similarly to what occurs in outbred strains of mice or in rats, GABAergic agonists impair memory and antagonists improve it, whilst the opposite is evident in the DBA strain. By contrast, post-training administration of selective D1 or D2 agonists impairs and post-training administration of selective antagonists improves retention in DBA mice, whilst these agents have opposite effects in the C57 strain. Dose- and strain-dependent effects are evident also following post-training corticosterone as well as opioid agonists and antagonists administration. On the other side, these two strains react similarly to oxotremorine (improvement) and to atropine (impairment) administration, DBA mice being more responsive to the effects of both drugs than C57 mice. Data on the interactions between agents acting upon different neurotransmitter and/or hormonal systems in these strains indicate strain-dependent synergistic or antagonistic interactions among some of these systems, pointing to inbred strains of mice as an important methodological tool in the study of neural and hormonal factors involved in emotion and in its effects on cognition. In particular, these studies have been carried out on inbred strains of mice from which recombinant inbred (RI) strains are available that have recently been proposed as a choice experimental method in psychopharmacogenetics.
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Affiliation(s)
- C Castellano
- Istituto di Psicobiologia e Psicofarmacologia, CNR, Rome, Italy
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18
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Cestari V, Mele A, Oliverio A, Castellano C. Amygdala lesions block the effect of cocaine on memory in mice. Brain Res 1996; 713:286-9. [PMID: 8725002 DOI: 10.1016/0006-8993(95)01556-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Post-training cocaine intraperitoneal administration enhanced memory consolidation in unoperated and sham-lesioned mice tested in a one-trial inhibitory avoidance task. Bilateral electrolytical amygdala lesions blocked this effect. The results are interpreted in terms of involvement of neurotransmitter, and in particular dopaminergic, systems in the effects of cocaine on memory.
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Affiliation(s)
- V Cestari
- Dipartimento di Genetica e Biologia Molecolare, Università degli Studi di Roma La Sapienz, Italy
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19
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Sakamoto H, Fitzgerald RD. Learning versus performance effects of cocaine on discriminative heart rate conditioning in rats. Psychopharmacology (Berl) 1995; 120:162-8. [PMID: 7480548 DOI: 10.1007/bf02246189] [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] [Indexed: 01/25/2023]
Abstract
The study examined the effects of cocaine on learning and performance of a classically conditioned heart rate (HR) discrimination in rats involving two auditory conditioned stimuli (CSs). In the discrimination protocol, one CS (CS+) was paired with the shock unconditioned stimulus (US) on a consistent basis and the other CS (CS-) was always presented alone. Four groups received an IP injection of 1, 3, 10, or 30 mg/kg cocaine and a fifth group received saline. Shortly after the injections, all groups were given six CS-alone trials, followed by 24 randomly sequenced discrimination conditioning trials (12 CS+ and 12 CS-). Approximately 72 h later, all groups were given six test trials with each CS in the absence of cocaine to evaluate the presence or absence of discrimination learning. All cocaine groups showed impaired discrimination performance on the discrimination conditioning trials, reductions in early pretest CS-alone responses, and reductions in resting HR. However, on the non-drug test trials discrimination performance was normal in all cocaine groups. The results established that in spite of major changes in HR dynamics, learning of the HR discrimination was not affected by cocaine but that cocaine did interfere with the performance of the discrimination. Except for the highest 30 mg group, the performance decrement appeared to be related to a cocaine-produced reduction in the capacity to inhibit bradycardia responding to the safe CS-. It was suggested that this loss of inhibitory control may have been due to cocaine changes in a corticothalamic pathway that controls inhibition of bradycardia to a safe CS-.
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Affiliation(s)
- H Sakamoto
- Oregon Health Sciences University, Department of Medical Psychology, Portland 97201-3098, USA
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20
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Puglisi-Allegra S, Cestari V, Cabib S, Castellano C. Strain-dependent effects of post-training cocaine or nomifensine on memory storage involve both D1 and D2 dopamine receptors. Psychopharmacology (Berl) 1994; 115:157-62. [PMID: 7862889 DOI: 10.1007/bf02244766] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Post-training administration of cocaine (1-10 mg/kg) or nomifensine (1-10 mg/kg) dose-dependently improves retention of an inhibitory avoidance response in C57BL16 mice, while impairign it in the DBA/2 strain. The effects of retention performance induced by the psychostimulant and the dopamine (DA) reuptake blocker in C57BL/6 and DBA/2 mice appear to be due to an effect on memory consolidation. In fact, they were observed when drugs were given at short, but not long, periods of time after training, i.e. when the memory trace is susceptible to modulation. Moreover, these effects are not to be ascribed to an aversive or a rewarding or non-specific action of the drugs on retention performance, as the latencies during the retention test of those mice that had not received a footshock during the training were not affected by the post-training drug administration. The strain-dependent effects of an intermediate dose (5 mg/kg) of both cocaine and nomifensine were reversed by pretreatment with either selective D1 or D2 DA receptor antagonist SCH 23390 and (-)-sulpiride administered at per se non-effective doses (0.025 and 6 mg/kg, respectively), thus suggesting that D1 and D2 receptor types are similarly involved in modulating memory processes. These results show that the effects of cocaine on memory consolidation are related to to its dopaminergic action, since they are similar to those produced by nomifensine and, what is more important, are antagonized by pretreatment with DA receptor antagonists.(ABSTRACT TRUNCATED AT 250 WORDS)
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21
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Abstract
Long-term potentiation (LTP) is a form of synaptic plasticity that may underlie learning and memory. The experiments reported here demonstrate that cocaine blocks the induction of LTP at the excitatory synapses in the CA1 region of the hippocampus, but does not appear to do so by blocking NMDA receptors or channels. Once LTP had been established, however, cocaine had no effect on the potentiated response. Cocaine was also able to block LTP initiated by superfusing slices with 25 mM TEA. The ability to block LTP was shared by the local anesthetics lidocaine and procaine, but not by tetrodotoxin, suggesting that the blockade of sodium channels alone did not disrupt LTP. Biochemical experiments demonstrated that cocaine can inhibit phosphorylation of purified Synapsin I by Ca2+/calmodulin-dependent protein kinase II. This effect, presumably mediated by effects on calmodulin, is a previously unreported action of cocaine, and suggests that cocaine at high dose levels might disrupt types of learning that are mediated by an LTP-like mechanism.
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Affiliation(s)
- D A Smith
- Neuroscience Program, Oberlin College, OH 44074
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22
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Abstract
The recent escalation of cocaine abuse has increased awareness of the need to understand the behavioral effects of cocaine and the determinants of those effects. Cocaine alters both conditioned and unconditioned behavior, and has prominent reinforcing and subjective effects that are particularly relevant to its abuse. An increase in CNS dopamine neurotransmission, resulting from a competitive blockade of high-affinity dopamine uptake mediated by both D1 and D2 dopamine receptors, is a primary determinant of the behavioral effects of cocaine. Either tolerance or sensitization may develop with repeated administration of cocaine. Dependence also develops, although the behavioral changes associated with cocaine withdrawal are subtle. Although numerous CNS changes have been associated with repeated administration of cocaine, the neuropharmacological mechanisms that underlie the behavioral changes that occur with repeated administration remain to be firmly established. Bill Woolverton and Ken Johnson stress that continued collaboration between behavioral pharmacologists and neuroscientists is critical for a complete understanding of the effects of cocaine.
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Affiliation(s)
- W L Woolverton
- Department of Pharmacological and Physiological Sciences, University of Chicago, IL 60637
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23
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Abstract
We reported previously that posttraining cocaine injections enhance subsequent performance of an automated jump-up avoidance response and a trough avoidance response in rats. In the present study we examined the species generality of the cocaine enhancement by investigating the effects of posttraining cocaine injection on subsequent performance of a one-way active avoidance response in mice. Cocaine (30 mg/kg, IP) administered to mice immediately following completion of two escape-only trials on day 1 significantly enhanced avoidance response performance on day 2. Neither lidocaine nor cocaine methiodide, when administered in doses equimolar to the effective cocaine dose, altered performance on day 2. These data indicate that cocaine's enhancement of avoidance responding in mice probably is neither peripherally mediated nor attributable to its local anesthetic properties.
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Affiliation(s)
- S B Weinberger
- Department of Psychology, University of California, Berkeley 94720
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24
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Abstract
The effects of cocaine and d-amphetamine administration on the acquisition of an automated jump-up active avoidance task were examined in two separate experiments. On days 1 and 2, male Sprague-Dawley rats received one escape-only training trial, followed immediately by the intraperitoneal injection of cocaine, amphetamine, or saline. On day 3, subjects received eight escape/avoidance trials. The posttraining administration of cocaine (2.75 and 5.55 mg/kg) and amphetamine (0.3 and 1.0 mg/kg) on days 1 and 2 facilitated jump-up avoidance performance on day 3. Importantly, both cocaine and amphetamine enhanced learning and memory under experimental conditions that allowed for drug-free training and testing.
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Affiliation(s)
- P H Janak
- Department of Psychology, University of California, Berkeley 94720
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25
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Castellano C, Cestari V, Cabib S, Puglisi-Allegra S. Post-training dopamine receptor agonists and antagonists affect memory storage in mice irrespective of their selectivity for D1 or D2 receptors. BEHAVIORAL AND NEURAL BIOLOGY 1991; 56:283-91. [PMID: 1684703 DOI: 10.1016/0163-1047(91)90439-w] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Post-training administration of the selective D1 and D2 agonists SKF 38393 and LY 171555 dose-dependently facilitated retention of an inhibitory avoidance response in mice, while the selective D1 or D2 antagonists SCH 23390 and (-)sulpiride produced an impairment of retention. These effects are not to be ascribed to a nonspecific action of the drugs on retention performance, as the latencies during the retention test of those mice that had not received a footshock during the training were not increased by the post-training drug administration. The effects on retention performance induced by DA agonists and antagonists seem to be due to an effect on memory consolidation, since they have been observed when drugs were given at short, but not at long, periods of time after training. These results showing a similar role of D1 and D2 receptor types on memory storage appear not to be consistent with a body of neuropharmacological, neurophysiological, and behavioral evidence pointing to a different functional role of these types of DA receptors. This discrepancy is discussed in terms of possible involvement of different brain systems, peripheral systems, or possible second messenger processes activated by the two receptor types and leading to similar effects on memory processes.
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- Animals
- Benzazepines/pharmacology
- Brain/drug effects
- Brain/physiology
- Dopamine Agents/pharmacology
- Dose-Response Relationship, Drug
- Ergolines/pharmacology
- Male
- Mental Recall/drug effects
- Mental Recall/physiology
- Mice
- Mice, Inbred C57BL
- Quinpirole
- Receptors, Dopamine/drug effects
- Receptors, Dopamine/physiology
- Receptors, Dopamine D1
- Receptors, Dopamine D2
- Retention, Psychology/drug effects
- Retention, Psychology/physiology
- Sulpiride/pharmacology
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Affiliation(s)
- C Castellano
- Istituto di Psicobiologia e Psicofarmacologia CNR, Roma, Italy
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26
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Marshall-Goodell B, Gormezano I. Effects of cocaine on conditioning of the rabbit nictitating membrane response. Pharmacol Biochem Behav 1991; 39:503-7. [PMID: 1946591 DOI: 10.1016/0091-3057(91)90216-o] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Two experiments were conducted to determine cocaine's (0, 1, 3, and 6 mg/kg) effects on associative, nonassociative, and motor processes in classical conditioning of the rabbit's nictitating membrane response (NMR). In Experiment 1, acquisition training consisted of tone- and light-conditioned stimuli (CSs) each paired on separate trials with a shock unconditioned stimulus (UCS). Cocaine injected prior to each session significantly impaired acquisition of conditioned responses (CRs). In Experiment 2, rabbits received cocaine injections prior to each training session involving explicitly unpaired CS-alone and UCS-alone presentations. Cocaine had no significant effects upon: base rate of NMRs; frequency of NMRs during presentations of the CSs; and frequency, amplitude, and latency of the UCRs. Consequently, cocaine's impairment of CR acquisition could not be attributed to its effects upon the nonassociative processes of base rate, sensitization, and pseudoconditioning, nor upon the sensory processing of the UCS and/or motor functioning of the UCR. Rather, cocaine's effects upon CR acquisition were mediated by the drug's effect upon associative processes. It appears likely that the drug affected the ability of the CS to enter into the associative conditioning process.
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