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Yu M, Lin L, Xu K, Xu M, Ren J, Niu X, Gao X, Zhang M, Yang Z, Dang J, Tao Q, Han S, Wang W, Cheng J, Zhang Y. Changes in aspartate metabolism in the medial-prefrontal cortex of nicotine addicts based on J-edited magnetic resonance spectroscopy. Hum Brain Mapp 2023; 44:6429-6438. [PMID: 37909379 PMCID: PMC10681642 DOI: 10.1002/hbm.26519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 09/05/2023] [Accepted: 10/04/2023] [Indexed: 11/03/2023] Open
Abstract
This study aims to explore the changes of the aspartate (Asp) level in the medial-prefrontal cortex (mPFC) of subjects with nicotine addiction (nicotine addicts [NAs]) using the J-edited 1 H MR spectroscopy (MRS), which may provide a positive imaging evidence for intervention of NA. From March to August 2022, 45 males aged 40-60 years old were recruited from Henan Province, including 21 in NA and 24 in nonsmoker groups. All subjects underwent routine magnetic resonance imaging (MRI) and J-edited MRS scans on a 3.0 T MRI scanner. The Asp level in mPFC was quantified with reference to the total creatine (Asp/Cr) and water (Aspwater-corr , with correction of the brain tissue composition) signals, respectively. Two-tailed independent samples t-test was used to analyze the differences in levels of Asp and other coquantified metabolites (including total N-acetylaspartate [tNAA], total cholinine [tCho], total creatine [tCr], and myo-Inositol [mI]) between the two groups. Finally, the correlations of the Asp level with clinical characteristic assessment scales were performed using the Spearman criteria. Compared with the control group (n = 22), NAs (n = 18) had higher levels of Asp (Asp/Cr: p = .005; Aspwater-corr : p = .004) in the mPFC, and the level of Asp was positively correlated with the daily smoking amount (Asp/Cr: p < .001; Aspwater-corr : p = .004). No significant correlation was found between the level of Asp and the years of nicotine use, Fagerstrom Nicotine Dependence (FTND), Russell Reason for Smoking Questionnaire (RRSQ), or Barratt Impulsivity Scale (BIS-11) score. The elevated Asp level was observed in mPFC of NAs in contrast to nonsmokers, and the Asp level was positively correlated with the amount of daily smoking, which suggests that nicotine addiction may result in elevated Asp metabolism in the human brain.
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Affiliation(s)
- Miaomiao Yu
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Liangjie Lin
- Clinical and Technical SupportPhilips HealthcareBeijingChina
| | - Ke Xu
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Man Xu
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Jianxin Ren
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Xiaoyu Niu
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Xinyu Gao
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Mengzhe Zhang
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Zhengui Yang
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Jinghan Dang
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Qiuying Tao
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Shaoqiang Han
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Weijian Wang
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Jingliang Cheng
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
| | - Yong Zhang
- Department of Magnetic Resonance ImagingThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina
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Yunusoğlu O. Rewarding effect of ethanol-induced conditioned place preference in mice: Effect of the monoterpenoid linalool. Alcohol 2022; 98:55-63. [PMID: 34800613 DOI: 10.1016/j.alcohol.2021.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 11/06/2021] [Accepted: 11/12/2021] [Indexed: 11/01/2022]
Abstract
Alcohol addiction is a chronic relapsing disease that is progressive and has severe detrimental health outcomes. The use of natural products has become popular for the treatment of side effects of drugs and substance abuse. Linalool is a monoterpenoid that exhibits several effects on the central nervous system. Linalool was identified to have beneficial effects on different mechanisms that are relevant in drug addiction or substance use disorder. The primary aim of the present study was to evaluate the therapeutic effect of linalool on the rewarding properties of alcohol in mice. Conditioned place preference (CPP) was established by intraperitoneal (i.p.) injection of ethanol (2 g/kg) during an 8-day conditioning trial. The effects of acamprosate and linalool on the rewarding properties of ethanol were tested in mice who received linalool (12.5, 25, and 50 mg/kg, i.p.) and acamprosate (300 mg/kg, i.p.) 30 min before each ethanol injection. CPP was extinguished by repeated testing, throughout which conditioned mice were administered daily linalool. Mice were lastly examined for reinstatement provoked by i.p. administration of single low-dose ethanol (0.4 g/kg, i.p.). Treatment with linalool reduced the acquisition and reinstatement, and precipitated the extinction of ethanol-induced CPP in mice. Acquisition and reinstatement of alcohol-induced CPP were significantly reduced by acamprosate, which also precipitated extinction. Ethanol alone and the combination with linalool or acamprosate did not alter locomotor activity. The results of this study suggest that linalool may have pharmacological effects for the treatment of alcohol addiction. In addition, further investigation is required to fully explore the benefits and possible adverse effects of linalool on alcohol addiction.
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Yunusoğlu O. Linalool attenuates acquisition and reinstatement and accelerates the extinction of nicotine-induced conditioned place preference in male mice. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2021; 47:422-432. [PMID: 33852814 DOI: 10.1080/00952990.2021.1898627] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Background: Nicotine is the addictive agent in tobacco products. The monoterpene linalool is the main ingredient in the essential oils of various aromatic plants. It has previously been demonstrated that linalool has beneficial effects on some mechanisms that are important in drug addiction.Objectives: The goal of the current study was to investigate the effect of linalool on nicotine-induced conditioned place preference (CPP) in male mice.Methods: CPP was induced by administering intraperitoneal (i.p.) injection of nicotine (0.5 mg/kg) during the conditioning phase. The effects of nicotinic acetylcholine receptor partial agonist varenicline and linalool on the rewarding characteristics of nicotine were tested in mice with administration of linalool (12.5, 25, and 50 mg/kg, i.p.), varenicline (2 mg/kg, i.p.) or saline 30 minutes before nicotine injection. CPP was extinguished by repeated testing, during which conditioned mice were administered varenicline and linalool every day. One day after the last extinction trial, mice that received linalool, varenicline or saline 30 minutes before a priming injection of nicotine (0.1 mg/kg, i.p.) were immediately tested for reinstatement of CPP.Results: Linalool attenuated nicotine acquisition (50 mg/kg, p < .01) and reinstatement (25 and 50 mg/kg, respectively p < .05, p < .01) and accelerated the extinction of nicotine-induced CPP (50 mg/kg, p < .05). Linalool exhibited similar effects on the reference drug varenicline in the CPP phases.Conclusion: These results suggest that linalool may be helpful as an adjuvant for the treatment of nicotine use disorder.
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Affiliation(s)
- Oruç Yunusoğlu
- Department of Pharmacology, Faculty of Medicine, Van Yuzuncu Yil University, Van, Turkey
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Dos Reis Izolan L, da Silva DM, Oliveira HBL, de Oliveira Salomon JL, Peruzzi CP, Garcia SC, Dallegrave E, Zanotto C, Elisabetsky E, Gonçalves CA, Arbo MD, Konrath EL, Leal MB. Sintocalmy, a Passiflora incarnata Based Herbal, Attenuates Morphine Withdrawal in Mice. Neurochem Res 2021; 46:1092-1100. [PMID: 33544325 DOI: 10.1007/s11064-021-03237-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 12/19/2020] [Accepted: 01/06/2021] [Indexed: 11/29/2022]
Abstract
Chronic opioid use changes brain chemistry in areas related to reward processes, memory, decision-making, and addiction. Both neurons and astrocytes are affected, ultimately leading to dependence. Passiflora incarnata L. (Passifloraceae) is the basis of frequently used herbals to manage anxiety and insomnia, with proven central nervous system depressant effects. Anti-addiction properties of P. incarnata have been reported. The aim of this study was to investigate the effect of a commercial extract of Passiflora incarnata (Sintocalmy®, Aché Laboratory) in the naloxone-induced jumping mice model of morphine withdrawal. In addition, glial fibrillary acidic protein (GFAP) and S100 calcium-binding protein B (S100B) levels were assessed in the frontal cortex and hippocampus, and DNA damage was verified on blood cells. In order to improve solubilization a Sintocalmy methanol extract (SME) was used. SME is mainly composed by flavonoids isovitexin and vitexin. The effects of SME 50, 100 and 200 mg/kg (i.p.) were evaluated in the naloxone-induced withdrawal syndrome in mice. SME 50 and SME 100 mg/kg decreased naloxone-induced jumping in morphine-dependent mice without reducing locomotor activity. No alterations were found in GFAP levels, however SME 50 mg/kg prevented the S100B increase in the frontal cortex and DNA damage. This study shows anti-addiction effects for a commercial standardized extract of P. incarnata and suggests the relevance of proper clinical assessment.
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Affiliation(s)
- Lucas Dos Reis Izolan
- Programa de Pós-Graduação em Ciências Biológicas - Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Douglas Marques da Silva
- Programa de Pós-Graduação em Ciências Biológicas - Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Laboratório de Farmacologia e Toxicologia de Produtos Naturais, Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Helena Beatriz Larrosa Oliveira
- Laboratório de Farmacologia e Toxicologia de Produtos Naturais, Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Janaína Lucas de Oliveira Salomon
- Laboratório de Farmacologia e Toxicologia de Produtos Naturais, Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Caroline Portela Peruzzi
- Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Solange C Garcia
- Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Eliane Dallegrave
- Departamento de Farmacociências, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Caroline Zanotto
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-anexo, Porto Alegre, Rio Grande do Sul, 90035-003, Brazil
| | - Elaine Elisabetsky
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-anexo, Porto Alegre, Rio Grande do Sul, 90035-003, Brazil
| | - Carlos Alberto Gonçalves
- Programa de Pós-Graduação em Ciências Biológicas - Bioquímica, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-anexo, Porto Alegre, Rio Grande do Sul, 90035-003, Brazil
| | - Marcelo Dutra Arbo
- Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Eduardo Luis Konrath
- Programa de Pós-Graduação em Ciências Farmacêuticas, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Mirna Bainy Leal
- Programa de Pós-Graduação em Ciências Biológicas - Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil. .,Laboratório de Farmacologia e Toxicologia de Produtos Naturais, Departamento de Farmacologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
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Silva AR, Dinis-Oliveira RJ. Pharmacokinetics and pharmacodynamics of dextromethorphan: clinical and forensic aspects. Drug Metab Rev 2020; 52:258-282. [DOI: 10.1080/03602532.2020.1758712] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Ana Rita Silva
- Department of Public Health and Forensic Sciences, and Medical Education, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Ricardo Jorge Dinis-Oliveira
- Department of Public Health and Forensic Sciences, and Medical Education, Faculty of Medicine, University of Porto, Porto, Portugal
- Department of Sciences, IINFACTS – Institute of Research and Advanced Training in Health Sciences and Technologies, University Institute of Health Sciences (IUCS), CESPU, CRL, Gandra, Portugal
- Department of Biological Sciences, Faculty of Pharmacy, Laboratory of Toxicology, UCIBIO, REQUIMTE, University of Porto, Porto, Portugal
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6
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Daily memantine treatment blunts hedonic response to sucrose in rats. Psychopharmacology (Berl) 2020; 237:103-114. [PMID: 31414153 DOI: 10.1007/s00213-019-05348-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 08/09/2019] [Indexed: 02/07/2023]
Abstract
RATIONALE Preclinical and clinical studies suggest the potential use of memantine in the treatment of binge eating disorder. The aim of this study was to further investigate the mechanisms by which memantine influences the motivational aspects of ingestion through the analysis of licking microstructure. To interpret treatment effects in relation to drug action at specific functionally relevant times, we compared the effect of two different administration schedules. METHODS Memantine was administered daily for a week, either 1 h before or immediately after a 30-min daily session. The effects on the microstructure of licking for a 10% sucrose solution in rats were examined in the course of treatment and for 15 days after treatment discontinuation. RESULTS Treatment before testing reduced ingestion due to reduced burst size and increased latency in the first session. However, a progressive increase in burst number across sessions led to a full recovery of ingestion levels by the end of treatment. Daily post-session administration induced a dramatic decrease of activation of licking behaviour, indicated by reduced burst number, accompanied to reduced burst size. A slow recovery of ingestion took place after treatment discontinuation. CONCLUSION These results suggest a reduced hedonic/reward evaluation response, an effect likely due to NMDA receptor blockade occurring during the testing time and support the hypothesis that memantine interferes with the hedonic/non-homeostatic mechanisms regulating food intake and food-seeking. The effect of post-session administration might be explained by the development of conditioned taste aversion.
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Rodger J. Understanding the Healing Potential of Ibogaine through a Comparative and Interpretive Phenomenology of the Visionary Experience. ANTHROPOLOGY OF CONSCIOUSNESS 2018. [DOI: 10.1111/anoc.12088] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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8
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Jergova S, Gordon CE, Gajavelli S, Sagen J. Experimental Gene Therapy with Serine-Histogranin and Endomorphin 1 for the Treatment of Chronic Neuropathic Pain. Front Mol Neurosci 2017; 10:406. [PMID: 29276474 PMCID: PMC5727090 DOI: 10.3389/fnmol.2017.00406] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 11/22/2017] [Indexed: 01/10/2023] Open
Abstract
The insufficient pain relief provided by current pharmacotherapy for chronic neuropathic pain is a serious medical problem. The enhanced glutamate signaling via NMDA receptors appears to be one of the key events in the development of chronic pain. Although effective, clinical use of systemic NMDA antagonists is limited by adverse effects such as hallucinations and motor dysfunction. Opioids are also potent analgesics but their chronic use is accompanied by tolerance and risk of addiction. However, combination of NMDA antagonists and opioids seems to provide a stable pain relieve at subthreshold doses of both substances, eliminating development of side effects. Our previous research showed that combined delivery of NMDA antagonist Serine histrogranin (SHG) and endomorphin1 (EM1) leads to attenuation of acute and chronic pain. The aim of this study was to design and evaluate an analgesic potency of the gene construct encoding SHG and EM1. Constructs with 1SHG copy in combination with EM1, 1SHG/EM1, and 6SHG/EM1 were intraspinally injected to animals with peripheral nerve injury-induced pain (chronic constriction injury, CCI) or spinal cord injury induced pain (clip compression model, SCI) and tactile and cold allodynia were evaluated. AAV2/8 particles were used for gene delivery. The results demonstrated 6SHG/EM1 as the most efficient for alleviation of pain-related behavior. The effect was observed up to 8 weeks in SCI animals, suggesting the lack of tolerance of possible synergistic effect between SHG and EM1. Intrathecal injection of SHG antibody or naloxone attenuated the analgesic effect in treated animals. Biochemical and histochemical evaluation confirmed the presence of both peptides in the spinal tissue. The results of this study showed that the injection of AAV vectors encoding combined SHG/EM constructs can provide long term attenuation of pain without overt adverse side effects. This approach may provide better treatment options for patients suffering from chronic pain.
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Affiliation(s)
- Stanislava Jergova
- The Miami Project, Miller School of Medicine, University of Miami, Miami, FL, United States
| | - Catherine E Gordon
- The Miami Project, Miller School of Medicine, University of Miami, Miami, FL, United States
| | - Shyam Gajavelli
- The Miami Project, Miller School of Medicine, University of Miami, Miami, FL, United States
| | - Jacqueline Sagen
- The Miami Project, Miller School of Medicine, University of Miami, Miami, FL, United States
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Beard E, Shahab L, Cummings DM, Michie S, West R. New Pharmacological Agents to Aid Smoking Cessation and Tobacco Harm Reduction: What Has Been Investigated, and What Is in the Pipeline? CNS Drugs 2016; 30:951-83. [PMID: 27421270 DOI: 10.1007/s40263-016-0362-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A wide range of support is available to help smokers to quit and to aid attempts at harm reduction, including three first-line smoking cessation medications: nicotine replacement therapy, varenicline and bupropion. Despite the efficacy of these, there is a continual need to diversify the range of medications so that the needs of tobacco users are met. This paper compares the first-line smoking cessation medications with (1) two variants of these existing products: new galenic formulations of varenicline and novel nicotine delivery devices; and (2) 24 alternative products: cytisine (novel outside Central and Eastern Europe), nortriptyline, other tricyclic antidepressants, electronic cigarettes, clonidine (an anxiolytic), other anxiolytics (e.g. buspirone), selective serotonin reuptake inhibitors, supplements (e.g. St John's wort), silver acetate, Nicobrevin, modafinil, venlafaxine, monoamine oxidase inhibitors (MAOIs), opioid antagonists, nicotinic acetylcholine receptor (nAChR) antagonists, glucose tablets, selective cannabinoid type 1 receptor antagonists, nicotine vaccines, drugs that affect gamma-aminobutyric acid (GABA) transmission, drugs that affect N-methyl-D-aspartate (NMDA) receptors, dopamine agonists (e.g. levodopa), pioglitazone (Actos; OMS405), noradrenaline reuptake inhibitors and the weight management drug lorcaserin. Six 'ESCUSE' criteria-relative efficacy, relative safety, relative cost, relative use (overall impact of effective medication use), relative scope (ability to serve new groups of patients) and relative ease of use-are used. Many of these products are in the early stages of clinical trials; however, cytisine looks most promising in having established efficacy and safety with low cost. Electronic cigarettes have become very popular, appear to be efficacious and are safer than smoking, but issues of continued dependence and possible harms need to be considered.
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Affiliation(s)
- Emma Beard
- Department of Epidemiology and Public Health, Cancer Research UK Health Behaviour Research Centre, University College London, London, WC1E 6BP, UK.
- Department of Clinical, Educational and Health Psychology, University College London, London, WC1E 6BP, UK.
| | - Lion Shahab
- Department of Epidemiology and Public Health, Cancer Research UK Health Behaviour Research Centre, University College London, London, WC1E 6BP, UK
| | - Damian M Cummings
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, WC1E 6BT, UK
| | - Susan Michie
- Department of Clinical, Educational and Health Psychology, University College London, London, WC1E 6BP, UK
| | - Robert West
- Department of Epidemiology and Public Health, Cancer Research UK Health Behaviour Research Centre, University College London, London, WC1E 6BP, UK
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Abdollahi H, Ghaemi-Jandabi M, Azizi H, Semnanian S. The role of orexin type-1 receptors in the development of morphine tolerance in locus coeruleus neurons: An electrophysiological perspective. Brain Res 2016; 1646:91-97. [DOI: 10.1016/j.brainres.2016.05.043] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 05/18/2016] [Accepted: 05/24/2016] [Indexed: 11/29/2022]
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Roberts-Wolfe DJ, Kalivas PW. Glutamate Transporter GLT-1 as a Therapeutic Target for Substance Use Disorders. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2016; 14:745-56. [PMID: 26022265 DOI: 10.2174/1871527314666150529144655] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Accepted: 05/18/2015] [Indexed: 12/13/2022]
Abstract
The development of new treatments for substance use disorders requires identification of targetable molecular mechanisms. Pathology in glutamatergic neurotransmission system in brain reward circuitry has been implicated in relapse to multiple classes of drugs. Glutamate transporter 1 (GLT-1) crucially regulates glutamatergic signaling by removing excess glutamate from the extrasynaptic space. The purpose of this review is to highlight the effects of addictive drug use on GLT-1 and glutamate uptake, and using GLT-1 as a target in addiction pharmacotherapy. Cocaine, opioids, ethanol, nicotine, amphetamines, and cannabinoids each affect GLT-1 expression and glutamate uptake, and restoring GLT-1 expression with N-acetylcysteine or ceftriaxone shows promise in correcting pre-clinical and clinical manifestations of drug addiction.
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Affiliation(s)
- Douglas J Roberts-Wolfe
- Department of Neuroscience, Medical University of So Carolina, 173 Ashley Ave, BSB403, Charleston, SC 29425, USA.
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12
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A Nonrewarding NMDA Receptor Antagonist Impairs the Acquisition, Consolidation, and Expression of Morphine Conditioned Place Preference in Mice. Mol Neurobiol 2016; 54:710-721. [PMID: 26768427 DOI: 10.1007/s12035-015-9678-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 12/23/2015] [Indexed: 02/03/2023]
Abstract
N-methyl-D-aspartate (NMDA) receptor antagonists block morphine-induced conditioned place preference (CPP). Although polyamines are endogenous modulators of the NMDA receptor, it is not known whether polyaminergic agents induce CPP or modulate morphine-induced CPP. Here, we examined whether polyamine ligands modify morphine CPP acquisition, consolidation, and expression. Adult male albino Swiss mice received saline (0.9 % NaCl, intraperitoneally (i.p.)) or morphine (5 mg/kg, i.p.) and were respectively confined to a black or a white compartment for 30 min for four consecutive days for CPP induction. The effect of arcaine (3 mg/kg, i.p.) or spermidine (30 mg/kg, i.p.), respectively, an antagonist and an agonist of the polyamine-binding site at the NMDA receptor, on the acquisition, consolidation, and expression of morphine CPP was studied. In those experiments designed to investigate whether spermidine prevented or reversed the effect of arcaine, spermidine (30 mg/kg, i.p.) was administered 15 min before or 15 min after arcaine, respectively. Arcaine and spermidine did not induce CPP or aversion per se. Arcaine (3 mg/kg, i.p.) impaired the acquisition, consolidation, and expression of morphine CPP. Spermidine prevented the impairing effect of arcaine on the acquisition of morphine CPP but not the impairing effect of arcaine on consolidation or expression of morphine CPP. These results suggest that arcaine may impair morphine CPP acquisition by modulating the polyamine-binding site at the NMDA receptor. However, the arcaine-induced impairment of consolidation and expression of morphine CPP seems to involve other mechanisms.
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The potential utility of some legal highs in CNS disorders. Prog Neuropsychopharmacol Biol Psychiatry 2016; 64:267-74. [PMID: 26232510 DOI: 10.1016/j.pnpbp.2015.07.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 07/24/2015] [Accepted: 07/26/2015] [Indexed: 12/21/2022]
Abstract
Over the last decade there has been an explosion of new drugs of abuse, so called legal highs or novel psychoactive substances (NPS). Many of these abused drugs have unknown pharmacology, but their biological effects can be anticipated from their molecular structure and possibly also from online user reports. When considered with the findings that some prescription medications are increasingly abused and that some abused drugs have been tested clinically one could argue that there has been a blurring of the line between drugs of abuse and clinically used drugs. In this review we examine these legal highs/NPS and consider whether, based on their known or predicted pharmacology, some might have the potential to be clinically useful in CNS disorders.
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Siahposht-Khachaki A, Fatahi Z, Haghparast A. Reduction of the Morphine Maintenance by Blockade of the NMDA Receptors during Extinction Period in Conditioned Place Preference Paradigm of Rats. Basic Clin Neurosci 2016; 7:341-350. [PMID: 27872695 PMCID: PMC5102563 DOI: 10.15412/j.bcn.03070407] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Introduction: Activation of N-methyl-d-aspartate (NMDA) glutamate receptors in the nucleus
accumbens is a component of drug-induced reward mechanism. In addition, NMDA
receptors play a major role in brain reward system and activation of these
receptors can change firing pattern of dopamine neurons. Blockade of glutamatergic
neurotransmission reduces the expression of conditioned place preference (CPP)
induced by morphine. Therefore, in this study, by using an NMDA receptor
antagonist, DL-2-Amino-5-phosphonopentanoic acid sodium salt (AP5), the role of
NMDA receptors on the maintenance and reinstatement of morphine-CPP was
investigated. Methods: Forty-three adult male albino Wistar rats were used in this study. After
subcutaneous administration of effective dose of morphine (5 mg/kg) during CPP
paradigm, the animals received intracerebroventricular doses of AP5(1, 5, and 25
mM/5μL saline) during extinction period (free morphine stage).
Conditioning score was recorded during extinction period and reinstatement phase.
Besides, another group of the animals received a single dose administration of
AP5(5 mM) just before the administration of ineffective dose of morphine (1 mg/kg)
in reinstatement phase. Results: The results revealed that two doses of this antagonist (5 and 25 mM) significantly
shortened the extinction period of morphine-CPP but did not reduce reinstatement
induced by priming dose of morphine. Moreover, the single dose administration of
AP5(5 mM) just before prime-morphine injection decreased reinstatement of
morphine-CPP. Conclusion: These findings indicate that blockade of NMDA receptors during extinction period
reduces maintenance but not reinstatement of morphine. In addition, blocking these
receptors in reinstatement phase decreases reinstatement to extinguished
morphine.
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Affiliation(s)
- Ali Siahposht-Khachaki
- Department of Physiology and Pharmacology, School of Medicine, Ramsar International Branch, Mazandaran University of Medical Sciences, Sari, Iran
| | - Zahra Fatahi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Abbas Haghparast
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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15
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Pringle G, McDonald MP, Gabriel KI. Patterns and Perceptions of Dextromethorphan Use in Adult Members of an Online Dextromethorphan Community. J Psychoactive Drugs 2015; 47:267-75. [PMID: 26266886 DOI: 10.1080/02791072.2015.1071448] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Dextromethorphan (DXM) is a widely available antitussive that has, at elevated dose levels, euphoric and dissociative effects. This article presents the reported patterns and preferences of DXM use, and perceptions of DXM use among adult members of an online DXM community. Analyses were conducted of quantitative and qualitative responses from nine female and 43 male individuals, aged 18-63 years old. All respondents reported illegal and DXM drug use, beginning, on average, at 15.7 and 17.1 years of age, respectively. The majority of respondents first heard about DXM online or from a friend, preferred to use DXM alone, ingested substances concurrently with DXM to modify its effects, had not been to an emergency room or arrested because of their DXM use, and used DXM for its dissociative and mind-altering effects. DXM was perceived as safe and in no need of further regulation with only 14% of respondents mentioning DXM's addictive qualities. Findings from this sample of adult DXM users reveal a sophisticated subculture in which users report using DXM specifically to induce changes to their mental state and use a variety of substances to modify or enhance DXM's effects.
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Affiliation(s)
- George Pringle
- a Department of Psychology , Central Washington University , Ellensburg , WA
| | - Michael P McDonald
- a Department of Psychology , Central Washington University , Ellensburg , WA
| | - Kara I Gabriel
- a Department of Psychology , Central Washington University , Ellensburg , WA
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16
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Lee SY, Chen SL, Chang YH, Chu CH, Chen SH, Chen PS, Huang SY, Tzeng NS, Wang LJ, Lee IH, Wang TY, Chen KC, Yang YK, Hong JS, Lu RB. A placebo-controlled trial of dextromethorphan as an adjunct in opioid-dependent patients undergoing methadone maintenance treatment. Int J Neuropsychopharmacol 2015; 18:pyv008. [PMID: 25716777 PMCID: PMC4540107 DOI: 10.1093/ijnp/pyv008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 01/16/2015] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Low-dose dextromethorphan (DM) might have anti-inflammatory and neurotrophic effects mechanistically remote from an NMDA receptor. In a randomized, double-blind, controlled 12 week study, we investigated whether add-on dextromethorphan reduced cytokine levels and benefitted opioid-dependent patients undergoing methadone maintenance therapy (MMT). METHODS Patients were randomly assigned to a group: DM60 (60mg/day dextromethorphan; n = 65), DM120 (120mg/day dextromethorphan; n = 65), or placebo (n = 66). Primary outcomes were the methadone dose required, plasma morphine level, and retention in treatment. Plasma tumor necrosis factor (TNF)-α, C-reactive protein, interleukin (IL)-6, IL-8, transforming growth factor-β1, and brain-derived neurotrophic factor (BDNF) levels were examined during weeks 0, 1, 4, 8, and 12. Multiple linear regressions with generalized estimating equation methods were used to examine the therapeutic effect. RESULTS After 12 weeks, the DM60 group had significantly longer treatment retention and lower plasma morphine levels than did the placebo group. Plasma TNF-α was significantly decreased in the DM60 group compared to the placebo group. However, changes in plasma cytokine levels, BDNF levels, and the methadone dose required in the three groups were not significantly different. CONCLUSIONS We provide evidence-decreased concomitant heroin use-of low-dose add-on DM's efficacy for treating opioid-dependent patients undergoing MMT.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Ru-Band Lu
- Department of Psychiatry, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan (Dr S-Y Lee); Department of Psychiatry, National Cheng Kung University, Tainan, Taiwan (Drs S-Y Lee, P Chen, I Lee, T-Y Wang, K Chen, Yang, and Lu); Department of Neurology, School of medicine, Kaohsiung Medical University, Kaohsiung, Taiwan (Dr S-L Chen); Institute of Allied Health Sciences, National Cheng Kung University, Tainan, Taiwan (Drs Chang and Lu); Laboratory of Neurobiology, NIH/NIEHS, Research Triangle Park, NC (Drs Chu and S-H Chen); Department of Psychiatry, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (Drs Huang and Tzeng); Department of Child and Adolescent Psychiatry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan (Drs L-J Wang, T-Y Wang, and Hong); Institute of Behavioral Medicine, College of Medicine and Hospital, National Cheng Kung University, Tainan, Taiwan (Dr Lu); Addiction Research Center, National Cheng Kung University, Tainan, Taiwan (Dr Lu); Center for Neuropsychiatric Research, National Health Research Institutes, Miaoli, Taiwan (Dr Lu).
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17
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A double-blind, placebo-controlled trial of dextromethorphan combined with clonidine in the treatment of heroin withdrawal. J Clin Psychopharmacol 2014; 34:508-12. [PMID: 24875077 DOI: 10.1097/jcp.0000000000000144] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Dextromethorphan has been reported to ameliorate opioid withdrawal symptoms in both animal and human subjects. In the present study, we investigated the efficacy of dextromethorphan as an add-on medication in heroin detoxification treatment in a double-blind, placebo-controlled design. Sixty-five heroin-dependent patients (male, 63; female, 2) participated in this inpatient detoxification trial after giving informed consent. Clonidine 0.075 mg 4 times a day was given as an antiwithdrawal medication at baseline. Each patient was then randomly assigned to treatment with either dextromethorphan 60 mg or placebo 4 times a day as additional medication. Flurazepam 30 mg was given before bedtime for insomnia. Other medications that were allowed included loperamide for diarrhea and lorazepam for agitation. Participants were monitored using the Objective Opioid Withdrawal Scale 3 times a day as the primary outcome to compare drug efficacy between groups. Generalized estimating equation model analysis revealed that the Objective Opioid Withdrawal Scale had no group difference between dextromethorphan and placebo group overall (P = 0.29), whereas a significant difference between groups was found during day 3 to day 6 (P = 0.04) by post hoc analysis. There was no difference in the Clinical Global Impression Scale, patient's impression of treatment, and use of ancillary medications between groups. No severe adverse effects were noticed. We suggest that dextromethorphan has some beneficial effect in attenuating the severity of opioid withdrawal symptoms and can be used as an adjunction medication in the treatment of opioid withdrawal, whereas the exact efficacy needs further investigation.
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18
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Lack of efficacy of dextromethorphan in managing alcohol withdrawal: a preliminary report of a randomized, double-blind, placebo-controlled trial. J Clin Psychopharmacol 2014; 34:149-52. [PMID: 24346753 DOI: 10.1097/jcp.0000000000000052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Alcohol withdrawal syndrome is associated with increased central N-methyl-D-aspartate (NMDA) glutamate transmission. Medications that reduce glutamate release or block NMDA overactivation have shown efficacy for treating alcohol withdrawal syndrome. Dextromethorphan (DXM), a widely used antitussive drug, is a low-affinity, noncompetitive NMDA antagonist with potential neuroprotective properties. This study, using a randomized, double-blind, placebo-controlled study design, examined the benefit of DXM in the management of acute alcohol withdrawal. Alcohol-dependent patients admitted for detoxification treatment and experiencing moderate alcohol withdrawal, as measured by a score greater than 10 on the revised Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar), were randomly assigned to receive either DXM 360 mg/d or an identical placebo for 7 days in a double-blind manner. All subjects received a concurrent dose of lorazepam 2 mg along with the initial administration of DXM or placebo and were given additional lorazepam (1 mg) as a rescue medication according to the symptom-triggered detoxification protocol. Outcome measures consisted of the mean total dose of lorazepam received, the sequential scores on the CIWA-Ar, and craving assessed by the Obsessive-Compulsive Drinking Scale. Forty subjects completed the study, 18 in the DXM group and 22 in the placebo group. We found that compared with placebo, DXM use was not associated with lower lorazepam doses to control alcohol withdrawal symptoms. The progression in CIWA-Ar and Obsessive-Compulsive Drinking Scale scores was also comparable between the 2 groups. Our preliminary results do not support the efficacy of high-dose DXM in reducing the need of benzodiazepines to treat withdrawal symptoms in alcohol-dependent patients.
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19
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Kalueff AV, Stewart AM, Gerlai R. Zebrafish as an emerging model for studying complex brain disorders. Trends Pharmacol Sci 2014; 35:63-75. [PMID: 24412421 DOI: 10.1016/j.tips.2013.12.002] [Citation(s) in RCA: 705] [Impact Index Per Article: 70.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 12/06/2013] [Accepted: 12/09/2013] [Indexed: 12/27/2022]
Abstract
The zebrafish (Danio rerio) is rapidly becoming a popular model organism in pharmacogenetics and neuropharmacology. Both larval and adult zebrafish are currently used to increase our understanding of brain function, dysfunction, and their genetic and pharmacological modulation. Here we review the developing utility of zebrafish in the analysis of complex brain disorders (including, e.g., depression, autism, psychoses, drug abuse, and cognitive deficits), also covering zebrafish applications towards the goal of modeling major human neuropsychiatric and drug-induced syndromes. We argue that zebrafish models of complex brain disorders and drug-induced conditions are a rapidly emerging critical field in translational neuroscience and pharmacology research.
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Affiliation(s)
- Allan V Kalueff
- ZENEREI Institute and the International Zebrafish Neuroscience Research Consortium (ZNRC), 309 Palmer Court, Slidell, LA 70458, USA.
| | - Adam Michael Stewart
- ZENEREI Institute and the International Zebrafish Neuroscience Research Consortium (ZNRC), 309 Palmer Court, Slidell, LA 70458, USA; Department of Neuroscience, University of Pittsburgh, A210 Langley Hall, Pittsburgh, PA 15260, USA
| | - Robert Gerlai
- Department of Psychology, University of Toronto at Mississauga, 3359 Mississauga Road North, Mississauga, Ontario L5L 1C6, Canada
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20
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Rath JM, Villanti AC, Abrams DB, Vallone DM. Patterns of tobacco use and dual use in US young adults: the missing link between youth prevention and adult cessation. JOURNAL OF ENVIRONMENTAL AND PUBLIC HEALTH 2012; 2012:679134. [PMID: 22666279 PMCID: PMC3361253 DOI: 10.1155/2012/679134] [Citation(s) in RCA: 188] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Accepted: 01/20/2012] [Indexed: 11/17/2022]
Abstract
Few studies address the developmental transition from youth tobacco use uptake to regular adulthood use, especially for noncigarette tobacco products. The current study uses online panel data from the Legacy Young Adult Cohort Study to describe the prevalence of cigarette, other tobacco product, and dual use in a nationally representative sample of young adults aged 18-34 (N = 4,201). Of the 23% of young adults who were current tobacco users, 30% reported dual use. Ever use, first product used, and current use were highest for cigarettes, cigars, little cigars, and hookah. Thirty-two percent of ever tobacco users reported tobacco product initiation after the age of 18 and 39% of regular users reported progressing to regular use during young adulthood. This study highlights the need for improved monitoring of polytobacco use across the life course and developing tailored efforts for young adults to prevent progression and further reduce overall population prevalence.
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Affiliation(s)
- Jessica M Rath
- Department of Research and Evaluation, Legacy, Washington, DC 20036, USA.
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21
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Hwang BY, Kim ES, Kim CH, Kwon JY, Kim HK. Gender differences in paclitaxel-induced neuropathic pain behavior and analgesic response in rats. Korean J Anesthesiol 2012; 62:66-72. [PMID: 22323957 PMCID: PMC3272532 DOI: 10.4097/kjae.2012.62.1.66] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Revised: 08/25/2011] [Accepted: 08/26/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Females show greater sensitivity than males to several modalities of experimental pain. However, the gender differences in paclitaxel-induced neuropathic pain have not been studied. The current study examined the gender differences in neuropathic pain behavior and the effect of analgesics in a paclitaxel-induced neuropathic pain model in rats. METHODS Neuropathic pain was induced by intraperitoneal injection of paclitaxel (2 mg/kg) on 4 alternate days in Sprague-Dawley rats of both genders. Mechanical allodynia was measured using a von Frey filament. The gender differences in analgesic responses were determined after administration of morphine (2 or 5 mg/kg), ketamine (2 or 5 mg/kg), or combined morphine (2 mg/kg) and ketamine (2 mg/kg). RESULTS Paclitaxel induced mechanical allodynia, which began to manifest on day 4, peaked within 10 days, and plateaued for at least 2 months after the first paclitaxel injection. No gender difference in the manifestation of mechanical allodynia was observed. A 2 mg/kg dose of ketamine increased the mechanical threshold only in males. The 5 mg/kg dose of ketamine significantly increased the mechanical threshold in both genders. Morphine (2 and 5 mg/kg) dose-dependently increased the mechanical thresholds in both genders. The 2 mg/kg dose of ketamine enhanced the antinociceptive effect of 2 mg/kg morphine only in females. CONCLUSIONS No gender difference in paclitaxel-induced neuropathic pain or analgesic response to ketamine or morphine was observed in Sprague-Dawley rats. Low dose ketamine enhanced the analgesic effect of morphine on paclitaxel-induced mechanical allodynia but only in female rats.
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Affiliation(s)
- Boo-Young Hwang
- Department of Anesthesia and Pain Medicine, Pusan National University School of Medicine, Busan, Korea
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22
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Bisaga A, Sullivan MA, Cheng WY, Carpenter KM, Mariani JJ, Levin FR, Raby WN, Nunes EV. A placebo controlled trial of memantine as an adjunct to oral naltrexone for opioid dependence. Drug Alcohol Depend 2011; 119:e23-9. [PMID: 21715107 PMCID: PMC3199033 DOI: 10.1016/j.drugalcdep.2011.05.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 05/13/2011] [Accepted: 05/17/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND Preclinical findings suggest that the inhibition of NMDA glutamatergic neurotransmission may have beneficial effects in the treatment of opioid dependence. AIMS We hypothesized that memantine, a low-potency, uncompetitive NMDA receptor antagonist, would be safe and effective when used as an adjunct to oral naltrexone in the treatment of opioid dependence, particularly in preventing relapse to opiate use in detoxified individuals. METHODS Opioid-dependent participants (N=112) were enrolled. Following detoxification all participants were inducted onto oral naltrexone and were randomized to receive memantine 15 mg bid (N=27), memantine 30 mg bid (N=27) or placebo (N=27) for 12-weeks in combination with naltrexone 50mg/day and individual relapse-prevention therapy. The primary outcome was the retention in treatment since treatment dropout is most commonly associated with relapse to opiate use. RESULTS Twenty-six percent of participants withdrew from treatment prior to starting naltrexone. Of those that were randomized 35% completed 4 weeks only, and 24% completed all 12 weeks of treatment. There was no significant difference in treatment retention or heroin use, opiate withdrawal symptoms and craving between the groups treated with memantine vs. placebo. CONCLUSION Thus, the efficacy of memantine 30 or 60 mg/day as an adjunct to oral naltrexone for the treatment of opiate dependence was not supported.
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Affiliation(s)
- Adam Bisaga
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA.
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23
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Du X, Elberger AJ, Matthews DB, Hamre KM. Heterozygous deletion of NR1 subunit of the NMDA receptor alters ethanol-related behaviors and regional expression of NR2 subunits in the brain. Neurotoxicol Teratol 2011; 34:177-86. [PMID: 21945132 DOI: 10.1016/j.ntt.2011.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Revised: 09/02/2011] [Accepted: 09/06/2011] [Indexed: 02/07/2023]
Abstract
NMDA receptors have been hypothesized to play a role in various aspects of ethanol-related phenotypes, notably in ethanol withdrawal. However, the role of each of the specific subunits remains unclear. To address this issue, mice that are heterozygous for the NR1 deletion, and thus have a reduction in functional NMDA receptors, were examined for ethanol consumption and acute ethanol withdrawal. Additionally, mice were examined for the level of vocalization following footshock, and behavior in an elevated plus maze, to determine their responses to stress. In these behavioral tests, NR1 heterozygous mice were shown to consume significantly higher levels of ethanol in the two bottle-choice test showing a possible role for this receptor in ethanol consumption. Analysis of acute withdrawal found that the heterozygous mice exhibit lower levels of handling-induced convulsions consistent with a role in ethanol sensitivity or withdrawal. In contrast, no effects on stress-related phenotypes were detected. Levels of NR2A-NR2D subunits of the NMDA receptor in specific brain regions were compared between NR1+/- mice and wild-type controls to assess whether the behavioral responses were specific to the diminution in NR1 expression or whether these changes could be due to secondary changes in expression of other NMDA subunits. Real-time quantitative PCR, Western blot and immunohistochemistry were used to examine expression levels in the hippocampus, neocortex, striatum and cerebellum. For the majority of the subunits, no differences were found between the wild-type and heterozygous mice in any of the brain regions. However, the NR2B subunit exhibited differences in expression of RNA in the hippocampus and protein levels in multiple brain regions, between wild-type and NR1+/- mice. These results show that NR1 plays a role, through mechanisms as yet unknown, in the expression of NR2 subunits in a region and subtype specific manner. This provides evidence of the effects of altered levels of NR1 expression on ethanol withdrawal and consumption, and suggests that concomitant changes in the levels of NR2B may contribute to that effect.
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Affiliation(s)
- Xiaoping Du
- Department of Anatomy and Neurobiology, University of Tennessee, Health Science Center, 855 Monroe Avenue, Memphis, TN 38163, USA
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24
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He Y, Wu FX, Miao XR, Xu XW, Sun YM, Chen CY, Yu WF. Suppression of acute morphine withdrawal syndrome by adenovirus-mediated β-endorphin in rats. Brain Res 2011; 1422:13-9. [PMID: 21983207 DOI: 10.1016/j.brainres.2011.07.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 07/15/2011] [Accepted: 07/31/2011] [Indexed: 10/17/2022]
Abstract
BACKGROUND Endogenous β-endorphin (β-EP) in the central nervous system (CNS) is decreased upon opioid addiction. The current study examined whether exogenous β-EP, delivered using an adenoviral vector into the CNS could attenuate morphine withdrawal syndrome in rats. METHODS The model of opioid-dependent rats was set up by receiving subcutaneous injection of morphine using an escalating regimen for 6days (5, 10, 20, 40, 50, 60mg/kg, three times/day). The adenovirus mediated β-EP gene was constructed based on our previous work. The ilea of opioid-dependent rats were isolated and treated with the supernatant of Ad-NEP. The basic and naloxone-induced (4μm/l) contractions of dependent ilea were recorded. The Ad-NEP was injected into the left lateral ventricle of the addition rats. The expression of the β-EP gene was verified by radioimmunoassay of the cerebrospinal fluid (CSF) and immunocytochemistry for β-EP. Withdrawal syndrome was evaluated after intraperitoneal injection of naloxone. RESULTS The contractions of dependent ilea were attenuated with supernatant containing β-EP expressed by Ad-NEP. Injection of the Ad-NEP resulted in significant increases in β-EP level in the CSF and β-EP-positive neurons. Rats receiving adenovirus carrying the β-EP gene had significantly less severe withdrawal symptoms upon naloxone challenge. CONCLUSIONS Exogenous β-EP mediated by adenovirus could attenuate withdrawal syndrome in morphine-dependent rats.
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Affiliation(s)
- Yan He
- Department of Anesthesiology, Eastern Hepatobiliary Surgery Hospital, the Second Military Medical University, Shanghai, 200438, People's Republic of China
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25
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Thoma R, Mullins P, Ruhl D, Monnig M, Yeo RA, Caprihan A, Bogenschutz M, Lysne P, Tonigan S, Kalyanam R, Gasparovic C. Perturbation of the glutamate-glutamine system in alcohol dependence and remission. Neuropsychopharmacology 2011; 36:1359-65. [PMID: 21389979 PMCID: PMC3096805 DOI: 10.1038/npp.2011.20] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
As acute ethanol exposure inhibits N-methyl-D-aspartate glutamate (Glu) receptors, sudden withdrawal from chronic alcohol use may lead to an increased activation of these receptors with excitotoxic effects. In the longer term, brain levels of Glu and its metabolites, such as glutamine (Gln), are likely to be chronically altered by alcohol, possibly providing a measure of overall abnormal Glu-Gln cycling. However, few studies have assessed concentrations of these metabolites in clinical populations of individuals with alcohol use disorders. Glu and Gln levels were compared in groups of 17 healthy controls and in 13 participants with alcohol dependence. Within the alcohol-dependent group, seven participants had current alcohol use disorder (AUD), and six had AUD in remission for at least 1 year (AUD-R). Neurometabolite concentrations were measured with proton magnetic resonance spectroscopy ((1)H-MRS) in a predominantly gray matter voxel that included the bilateral anterior cingulate gyri. Tissue segmentation provided an assessment of the proportion of gray matter in the (1)H-MRS voxel. The Drinker Inventory of Consequences (DrInC) and Form-90 were administered to all participants to quantify alcohol consequences and use. Glu level was lower and Gln level was higher in the AUD and AUD-R groups relative to the control group; creatine, choline, myo-inositol, and total N-acetyl groups, primarily N-acetylaspartate did not differ across groups. These results were not confounded by age, sex, or proportion of gray matter in the (1)H-MRS voxel. Neurometabolite concentrations did not differ between AUD and AUD-R groups. Subsequent regressions in the combined clinical group, treating voxel gray matter proportion as a covariate, revealed that total score on the DrInC was positively correlated with Gln but negatively correlated with both Glu and gray matter proportion. Regression analyses, including DrInC scores and smoking variables, identified a marginal independent effect of smoking on Gln. The current findings of higher Gln and lower Glu in the combined AUD and AUD-R groups might indicate a perturbation of the Glu-Gln cycle in alcohol use disorders. The absence of differences in mean Glu and Gln between the AUD and AUD-R groups suggests that altered Glu-Gln metabolism may either predate the onset of abuse or persist during prolonged abstinence.
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Affiliation(s)
| | - Paul Mullins
- Mind Research Network, Albuquerque, NM, USA,Bangor Imaging Center, School of Psychology, Bangor University, Gwynedd, UK
| | - David Ruhl
- Mind Research Network, Albuquerque, NM, USA
| | - Mollie Monnig
- Mind Research Network, Albuquerque, NM, USA,Department of Psychology, University of New Mexico, Albuquerque, NM, USA
| | - Ronald A Yeo
- Department of Psychology, University of New Mexico, Albuquerque, NM, USA
| | | | - Michael Bogenschutz
- Department of Psychiatry, Center for Neuropsychological Services, University of New Mexico, Albuquerque, NM, USA
| | - Per Lysne
- Mind Research Network, Albuquerque, NM, USA,Department of Psychology, University of New Mexico, Albuquerque, NM, USA
| | - Scott Tonigan
- Center on Alcoholism, Substance Abuse, and Addictions (CASAA), Albuquerque, NM, USA
| | | | - Charles Gasparovic
- Mind Research Network, Albuquerque, NM, USA,Department of Psychology, University of New Mexico, Albuquerque, NM, USA
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Mattioli L, Perfumi M. Effects of a Rhodiola rosea L. extract on acquisition and expression of morphine tolerance and dependence in mice. J Psychopharmacol 2011; 25:411-20. [PMID: 20142299 DOI: 10.1177/0269881109359096] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This study investigated the effect of Rhodiola rosea L. extract on acquisition and expression of morphine tolerance and dependence in mice. Therefore animals were injected with repeated administration of morphine (10 mg/kg, subcutaneous) twice daily for five or six days, in order to make them tolerant or dependent. Rhodiola rosea L. extract (0, 10, 15 and 20 mg/kg) was administered by the intragastric route 60 min prior to each morphine injection (for acquisition) or prior the last injection of morphine or naloxone on test day (for tolerance or dependence expression, respectively). Morphine tolerance was evaluated by testing its analgesic effect in the tail flick test at the 1st and 5th days. Morphine dependence was evaluated by counting the number of withdrawal signs (jumping, rearing, forepaw tremor, teeth chatter) after naloxone injection (5 mg/kg; intraperitoneal) on the test day (day 6). Results showed that Rhodiola rosea L. extract significantly reduced the expression of morphine tolerance, while it was ineffective in modulating its acquisition. Conversely, Rhodiola rosea L. extract significantly and dose-dependently attenuated both development and expression of morphine dependence after chronic or acute administration. These data suggest that Rhodiola rosea L. may have human therapeutic potential for treatment of opioid addiction.
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Affiliation(s)
- Laura Mattioli
- Department of Experimental Medicine and Public Health, University of Camerino, via Madonna delle Carceri, 62032 Camerino, Italy
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27
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Popik P, Kos T, Zhang Y, Bisaga A. Memantine reduces consumption of highly palatable food in a rat model of binge eating. Amino Acids 2011; 40:477-85. [PMID: 20571841 PMCID: PMC3020289 DOI: 10.1007/s00726-010-0659-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2009] [Accepted: 06/11/2010] [Indexed: 01/03/2023]
Abstract
Excessive consumption of highly palatable food has been linked to the development of eating disorders and obesity, and can be modeled in non-food-deprived rats by offering them a limited (2-h daily) access to an optional dietary fat. Since the glutamatergic system has recently emerged as a viable target for binge-eating medication development, we compared the effects of subchronic treatment with glutamatergic receptor antagonists to the effects of a reference appetite-suppressing agent sibutramine on highly palatable food (lard) and normal chow intake. In three separate experiments, the consumption of a standard laboratory chow and lard were measured during 12 days of medication treatment and for 6 days afterwards. Generalized estimating equations analysis demonstrated that sibutramine (7.5 mg/kg, p.o.) significantly decreased lard consumption, with a concurrent increase in chow consumption. Sibutramine effects disappeared after treatment discontinuation. The NMDA receptor antagonist memantine (5 mg/kg, i.p.) significantly decreased lard consumption and increased chow consumption, comparable to effects of sibutramine; however, memantine's effects persisted after treatment discontinuation. The effects of the mGluR5 antagonist MTEP (7.5 mg/kg, i.p.) on food consumption were in the same direction as seen with memantine, but the observed differences were not significant. In an additional control experiment, sibutramine and memantine reduced unlimited (24 h) chow intake during the treatment phase. Present results provide evidence that glutamatergic neurotransmission might be involved in the regulation of excessive consumption of highly palatable foods, and suggest that NMDA receptor may be an attractive target for developing obesity and disordered eating pharmacotherapies.
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Affiliation(s)
- Piotr Popik
- Behavioral Neuroscience, Institute of Pharmacology Polish Academy of Sciences, 12 Smetna Street, 31-343, Krakow, Poland.
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Biological and psychological interventions: trends in substance use disorders intervention research. Addict Behav 2010; 35:1083-8. [PMID: 20729001 DOI: 10.1016/j.addbeh.2010.07.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 07/16/2010] [Indexed: 10/19/2022]
Abstract
Substance use disorders (SUDs) cause serious medical, financial, and social problems for individuals and society. Thus, understanding the large body of research exploring biological and psychological intervention trends is important to researchers and clinicians. Historically, psychological interventions have dominated the literature, in spite of modest outcome data. Recently, a refocus on biological intervention research has led to results suggested as efficacious in treatment of SUDs with promising clinical potential. The current review indicates that there seems to be some incongruence between this growing body of physiological research and psychological clinical research and practice. The current review explores these trends and argues for more solid integration of biological and psychological research and treatment strategies for SUDs, as well as heightened efforts toward translation of research into practice.
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Nagy J, Kolok S, Boros A, Dezso P. Role of altered structure and function of NMDA receptors in development of alcohol dependence. Curr Neuropharmacol 2010; 3:281-97. [PMID: 18369402 DOI: 10.2174/157015905774322499] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2005] [Accepted: 07/18/2005] [Indexed: 11/22/2022] Open
Abstract
Long-term alcohol exposure gives rise to development of physical dependence on alcohol in consequence of changes in certain neurotransmitter functions. Accumulating evidence suggests that the glutamatergic neurotransmitter system, especially the N-methyl-D-aspartate (NMDA) type of glutamate receptors is a particularly important site of ethanol's action, since ethanol is a potent inhibitor of the NMDA receptors (NMDARs) and prolonged ethanol exposition leads to a compensatory "upregulation" of NMDAR mediated functions supposedly contributing to the occurrence of ethanol tolerance, dependence as well as the acute and delayed signs of ethanol withdrawal.Recently, expression of different types of NMDAR subunits was found altered after long-term ethanol exposure. Especially, the expression of the NR2B and certain splice variant forms of the NR1 subunits were increased in primary neuronal cultures treated intermittently with ethanol. Since NMDA ion channels with such an altered subunit composition have increased permeability for calcium ions, increased agonist sensitivity, and relatively slow closing kinetics, the abovementioned alterations may underlie the enhanced NMDAR activation observed after long-term ethanol exposure. In accordance with these changes, the inhibitory potential of NR2B subunit-selective NMDAR antagonists is also increased, demonstrating excellent potency against alcohol withdrawal-induced in vitro cytotoxicity. Although in vivo data are few with these compounds, according to the effectiveness of the classic NMDAR antagonists in attenuation, not only the physical symptoms, but also some affective and motivational components of alcohol withdrawal, novel NR2B subunit selective NMDAR antagonists may offer a preferable alternative in the pharmacotherapy of alcohol dependence.
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Affiliation(s)
- József Nagy
- Gedeon Richter Ltd., Pharmacological and Drug Safety Research, Budapest 10. P.O.Box 27, H-1475, Hungary.
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Zawertailo LA, Tyndale RF, Busto U, Sellers EM. Effect of metabolic blockade on the psychoactive effects of dextromethorphan. Hum Psychopharmacol 2010; 25:71-9. [PMID: 20041473 DOI: 10.1002/hup.1086] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE Variation in the activity of cytochrome P450 2D6 (CYP2D6) affects the pharmacokinetics and effectiveness of dextromethorphan (DM), because it controls the production of dextrorphan, an active metabolite, with higher affinity for the NMDA receptor than the parent compound. This study examined whether pharmacological inhibition of CYP2D6 activity with quinidine would mimic the genetic mutation and thus also alter the psychoactive effects of DM. METHODS In a single-blind, within-subjects study, eight healthy volunteers (all homozygous for the wild type allele for CYP2D6) received placebo and varying doses of DM, both with and without quinidine pre-treatment. Pharmacokinetic and pharmacodynamic measures were assessed at baseline and every hour post-drug for 6 h. RESULTS Compared to the no quinidine condition, quinidine pre-treatment decreased the area under the dose-response curve on subjective measures of positively reinforcing effects (e.g., euphoria, p < 0.04; drug liking, p < 0.05), and was significantly greater for measures of dysphoria (e.g., unpleasantness, p < 0.02). These changes corresponded to increased DM and decreased dextrorphan plasma concentrations. CONCLUSIONS Compared to DM alone, quinidine pre-treatment inhibited DM metabolism and changed its subjective effects, demonstrating that the psychoactive properties of DM are a function of drug metabolism. These results demonstrate the relationship between CYP2D6 activity, plasma drug levels, and psychoactive drug effects, and have implications for both the abuse liability and therapeutic utility of DM.
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Affiliation(s)
- Laurie A Zawertailo
- Centre for Addiction and Mental Health, Nicotine Dependence Clinic, Toronto, Ontario, Canada.
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31
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Kaufman MJ, Prescot AP, Ongur D, Evins AE, Barros TL, Medeiros CL, Covell J, Wang L, Fava M, Renshaw PF. Oral glycine administration increases brain glycine/creatine ratios in men: a proton magnetic resonance spectroscopy study. Psychiatry Res 2009; 173:143-9. [PMID: 19556112 PMCID: PMC2713375 DOI: 10.1016/j.pscychresns.2009.03.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2008] [Revised: 03/05/2009] [Accepted: 03/10/2009] [Indexed: 11/30/2022]
Abstract
Oral high-dose glycine administration has been used as an adjuvant treatment for schizophrenia to enhance glutamate neurotransmission and mitigate glutamate system hypofunction thought to contribute to the disorder. Prior studies in schizophrenia subjects documented clinical improvements after 2 weeks of oral glycine administration, suggesting that brain glycine levels are sufficiently elevated to evoke a clinical response within that time frame. However, no human study has reported on brain glycine changes induced by its administration. We utilized a noninvasive proton magnetic resonance spectroscopy ((1)H-MRS) technique termed echo time-averaged (TEAV) (1)H-MRS, which permits noninvasive quantification of brain glycine in vivo, to determine whether 2 weeks of oral glycine administration (peak dose of 0.8 g/kg/day) increased brain glycine/creatine (Gly/Cr) ratios in 11 healthy adult men. In scans obtained 17 h after the last glycine dose, brain (Gly/Cr) ratios were significantly increased. The data indicate that it is possible to measure brain glycine changes with proton spectroscopy. Developing a more comprehensive understanding of human brain glycine dynamics may lead to optimized use of glycine site agonists and glycine transporter inhibitors to treat schizophrenia, and possibly to treat other disorders associated with glutamate system dysfunction.
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Affiliation(s)
- Marc J. Kaufman
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478,Address Correspondence to: Marc J. Kaufman, Ph.D., Brain Imaging Center, McLean Hospital, 115 Mill St., Belmont, MA 02478 USA, 617-855-3469 (office), 617-855-2770 (FAX),
| | - Andrew P. Prescot
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Dost Ongur
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | | | - Tanya L. Barros
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Carissa L. Medeiros
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Julie Covell
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
| | - Liqun Wang
- Translational Medicine and Genetics, GlaxoSmithKline, Greenford, United Kingdom
| | | | - Perry F. Renshaw
- Brain Imaging Center, McLean Hospital, Harvard Medical School, Belmont, MA 02478
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Twede VD, Teichert RW, Walker CS, Gruszczyński P, Kaźmierkiewicz R, Bulaj G, Olivera BM. Conantokin-Br from Conus brettinghami and selectivity determinants for the NR2D subunit of the NMDA receptor. Biochemistry 2009; 48:4063-73. [PMID: 19309162 DOI: 10.1021/bi802259a] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Conantokins are venom peptides from marine cone snails that are NMDA receptor antagonists. Here, we report the characterization of a 24 AA conantokin from Conus brettinghami Coomans , H. E. , Moolenbeek , R. G. and Wils , E. ( 1982 ) Basteria 46 ( 1/4 ), 3 - 67 , conantokin-Br (con-Br), the first conantokin that does not have the conserved glutamate residue at position 2. Molecular modeling studies suggest that con-Br has a helical structure between residues 2-13. In contrast to other characterized conantokins, con-Br has a high potency for NMDA receptors with NR2D subunits. To identify determinants for NR2D potency, we synthesized chimeras of con-Br and conantokin-R (con-R); the latter has a approximately 30-fold lower potency for the NR2D subtype. The characterization of two reciprocal chimeras (con-Br/R and con-R/Br), comprising the first 9-10 N-terminal AAs of each conantokin followed by the corresponding C-terminal AAs of the other conantokin demonstrates that determinants for NR2D selectivity are at the N-terminal region. Additional analogues comprising 1-3 amino acid substitutions from each peptide into the homologous region of the other led to the identification of a key determinant; a Tyr residue in position 5 increases potency for NR2D, while Val at this locus causes a decrease. The systematic definition of key determinants in the conantokin peptides for NMDA receptor subtype selectivity is an essential component in the development of conantokin peptides that are highly selective for each specific NMDA receptor subtype.
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Affiliation(s)
- Vernon D Twede
- Department of Biology, University of Utah, Salt Lake City, Utah 84112, USA.
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Zdanys K, Tampi RR. A systematic review of off-label uses of memantine for psychiatric disorders. Prog Neuropsychopharmacol Biol Psychiatry 2008; 32:1362-74. [PMID: 18262702 DOI: 10.1016/j.pnpbp.2008.01.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Revised: 12/30/2007] [Accepted: 01/09/2008] [Indexed: 12/26/2022]
Abstract
Recent data points to glutamatergic dysfunction in mood disorders, anxiety disorders, obsessive-compulsive disorder, and schizophrenia. Memantine, a drug approved by the FDA for the treatment of moderate to severe Alzheimer's disease that acts at the N-methyl-d-aspartate receptor, has been used off-label for various psychiatric disorders. Although promising, the available data for the use of memantine in these disorders is limited. Given this data, the routine use of memantine for depression, schizophrenia, obsessive-compulsive disorder, substance abuse, pervasive developmental disorders, bipolar disorder, and binge eating disorder cannot be recommended at this time.
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Affiliation(s)
- Kristina Zdanys
- Yale University School of Medicine, Department of Psychiatry, LV-121 Yale New Haven Psychiatric Hospital, 184 Liberty Street, New Haven, CT 06519, United States.
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Akerele E, Bisaga A, Sullivan MA, Garawi F, Comer SD, Thomas AA, Nunes EV, Kleber HD. Dextromethorphan and quinidine combination for heroin detoxification. Am J Addict 2008; 17:176-80. [PMID: 18463993 DOI: 10.1080/10550490802019543] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Dextromethorphan (DM) is a low-affinity, non-competitive NMDA receptor antagonist that has shown promise in preclinical and preliminary clinical studies for the reduction of opioid withdrawal symptoms, but when used at higher doses, it is associated with deleterious side effects attributed to its metabolite, dextrorphan. A clinical trial was therefore conducted to test the withdrawal-suppressant effect of a combination of dextromethorphan with quinidine (DM/Q). Quinidine inhibits the metabolism of dextromethorphan, reducing dextrorphan levels. Opioid-dependent patients were admitted to an inpatient unit, stabilized for three days on morphine (25 mg, sc, every six hours), and randomly assigned on day 2 to DM/Q (30 mg/30 mg, twice a day) (n = 22) or matching placebo (n = 9) prior to the discontinuation of morphine on day 4. Withdrawal symptoms, measured with the Modified Himmelsbach Opioid Withdrawal Scale (MHOWS), increased significantly on days 4 and 5 (Z = 3.70, p = .0002), and by day 6, 90% of the sample (28/31) had dropped out of the study. There were no differences between treatment groups on either outcome measure. The combination of dextromethorphan and quinidine appears ineffective as a primary treatment for opioid withdrawal. Future studies should examine dextromethorphan as an adjunct to other anti-withdrawal medications and focus more on the relationship between dextrorphan levels and withdrawal suppression.
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Affiliation(s)
- Evaristo Akerele
- Department of Psychiatry, Columbia University College of Physicians & Surgeons, New York, New York, USA
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Ko SW, Wu LJ, Shum F, Quan J, Zhuo M. Cingulate NMDA NR2B receptors contribute to morphine-induced analgesic tolerance. Mol Brain 2008; 1:2. [PMID: 18803856 PMCID: PMC2546399 DOI: 10.1186/1756-6606-1-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Accepted: 06/17/2008] [Indexed: 11/10/2022] Open
Abstract
Morphine is widely used to treat chronic pain, however its utility is hindered by the development of tolerance to its analgesic effects. While N-methyl-D-aspartate (NMDA) receptors are known to play roles in morphine tolerance and dependence, less is known about the roles of individual NMDA receptor subtypes. In this study, Ro 256981, an antagonist of the NMDA receptor subunit NR2B, was used to reduce the expression of analgesic tolerance to morphine. The mechanisms altered with chronic drug use share similarities with those underlying the establishment of long-tem potentiation (LTP) and behavioral memory. Since NMDA NR2B receptors in the anterior cingulate cortex (ACC) play roles in the establishment of LTP and fear memory, we explored their role in changes that occur in this region after chronic morphine. Both systemic and intra-ACC inhibition of NR2B in morphine-tolerant animals inhibited the expression of analgesic tolerance. Electrophysiological recordings revealed a significant increase in the NR2B component of NMDA receptor mediated excitatory postsynaptic currents (EPSCs), at both synaptic and extra-synaptic sites. However, there was no change in alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor mediated EPSCs. This study suggests that selective inhibition of NMDA NR2B receptors may prove useful in combating the development of analgesic tolerance to morphine and proposes a novel role for the ACC in opioid tolerance and morphine induced changes in synaptic plasticity.
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Affiliation(s)
- Shanelle W Ko
- Department of Physiology, University of Toronto, University of Toronto Centre for the Study of Pain, Canada.
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Bisaga A, Kos T, Wójcikowski J, Daniel WA, Popik P. Brain levels of dextromethorphan and the intensity of opioid withdrawal in mice. Drug Alcohol Depend 2008; 95:147-51. [PMID: 18328640 DOI: 10.1016/j.drugalcdep.2008.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Accepted: 01/04/2008] [Indexed: 01/11/2023]
Abstract
Consistent with their antagonistic actions at N-methyl-D-aspartate type glutamate receptors, dextromethorphan (DXM) and its metabolite, dextrorphan (DXT) decrease the intensity of opioid withdrawal syndrome. Since quinidine (QND) affects CYP2D6-mediated metabolism and P-glycoprotein governed transport, we sought to determine whether co-treatment with QND would affect brain levels of DXM and DXT as well as the effect of these compounds on opioid withdrawal syndrome in mice. We found that DXM dose dependently inhibited the intensity of opioid withdrawal syndrome and that there was a tendency for a further decrease when QND was co-administered with DXM. Administration of 30 mg/kg of DXM resulted in higher brain levels of DXM and DXT than administration of 10 mg/kg of DXM, but much lower DXT levels than that produced by 30 mg/kg of DXT. Co-treatment with QND resulted in higher brain levels of DXM (but not DXT) suggesting that QND produces an increase in the brain availability of DXM. In summary, brain levels of DXM were inversely correlated with the intensity of opioid withdrawal syndrome. QND induced increased brain levels of DXM tend to attenuate the intensity of opioid withdrawal syndrome. We suggest that it is DXM, rather than DXT, that is responsible for the attenuating effect on the intensity of opioid withdrawal syndrome, and that the beneficial action of QND on the effect of DXM should be more pronounced in humans.
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Affiliation(s)
- Adam Bisaga
- Division on Substance Abuse, Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY, USA
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Jain R, Mukherjee K, Balhara YPS. The role of NMDA receptor antagonists in nicotine tolerance, sensitization, and physical dependence: a preclinical review. Yonsei Med J 2008; 49:175-88. [PMID: 18452252 PMCID: PMC2615322 DOI: 10.3349/ymj.2008.49.2.175] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2007] [Accepted: 05/30/2007] [Indexed: 12/04/2022] Open
Abstract
Nicotine, the primary psychoactive component of tobacco products, produces diverse neurophysiological, motivational, and behavioral effects through several brain regions and neurochemical pathways. Various neurotransmitter systems have been explored to understand the mechanisms behind nicotine tolerance, dependence, and withdrawal. Recent evidence suggests that glutamate neurotransmission has an important role in this phenomenon. The aim of the present review is to discuss preclinical findings concerning the role of N-methyl-D-aspartate (NMDA) receptor neurotransmission in mediating the behavioral effects of nicotine, tolerance, sensitization, dependence, and withdrawal. Based on preclinical findings, it is hypothesized that NMDA receptors mediate the common adaptive processes that are involved in the development, maintenance, and expression of nicotine addiction. Modulation of glutamatergic neurotransmission with NMDA receptor antagonists may prove to be useful in alleviating the symptoms of nicotine abstinence and facilitate tobacco-smoking cessation.
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Affiliation(s)
- Raka Jain
- National Drug Dependence Treatment Centre and Department of Psychiatry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, Pin 110029, India.
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Effects of the NMDA receptor antagonist memantine on the expression and development of acute opiate dependence as assessed by withdrawal-potentiated startle and hyperalgesia. Psychopharmacology (Berl) 2008; 196:649-60. [PMID: 18026718 DOI: 10.1007/s00213-007-0998-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Accepted: 10/25/2007] [Indexed: 12/24/2022]
Abstract
RATIONALE While the N-methyl-D: -aspartate (NMDA) glutamate receptor has been strongly implicated in chronic opiate dependence, relatively few studies have examined the effects of NMDA receptor antagonists on withdrawal from acute opiate exposure. OBJECTIVES The current study examined the effects of memantine, a well-tolerated NMDA receptor antagonist, on acute opiate dependence as assessed by elevations in rodent startle responding (i.e., "withdrawal-potentiated startle") and increased pain sensitivity (i.e., hyperalgesia). RESULTS Administration of memantine either attenuated (5 mg/kg) or blocked (10 mg/kg) the expression of withdrawal-potentiated startle during naloxone (2.5 mg/kg)-precipitated withdrawal from a single dose of morphine sulfate (10 mg/kg). Pre-treatment with the NMDA receptor antagonist also inhibited the exacerbation of withdrawal-potentiated startle across repeated acute opiate exposures. Memantine blocked the expression of acute dependence, but was less effective in inhibiting its escalation, when hyperalgesia was used as a measure of withdrawal. These doses of memantine did not affect startle responding or nociception in otherwise drug-free animals. Data from additional control groups indicated that the effects of memantine on the expression of withdrawal were not influenced by nonspecific interactions between the NMDA antagonist and either morphine or naloxone. CONCLUSIONS These findings suggest that the NMDA receptor may play a key role in the earliest stages of opiate dependence and provide further evidence that memantine may be useful for the treatment of opiate withdrawal.
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Mendez IA, Trujillo KA. NMDA receptor antagonists inhibit opiate antinociceptive tolerance and locomotor sensitization in rats. Psychopharmacology (Berl) 2008; 196:497-509. [PMID: 17994223 DOI: 10.1007/s00213-007-0984-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2007] [Accepted: 10/12/2007] [Indexed: 10/22/2022]
Abstract
RATIONALE N-Methyl-D: -aspartate (NMDA) receptors have an important role in different forms of behavioral and neural plasticity. Evidence suggests that these receptors may also be involved in plasticity arising from long-term treatment with different drugs of abuse, including tolerance, sensitization, and physical dependence. There is abundant evidence demonstrating that NMDA receptors are involved in tolerance to opiate-induced antinociception; however, the role of these receptors in sensitization to the locomotor effects of opiates is more controversial. OBJECTIVE The ability of NMDA receptor antagonists to modify the development of sensitization to the locomotor stimulant effect of three different opiates was examined. In selected studies, the ability of the antagonists to modify tolerance to the antinociceptive effects of the opiates was also examined. MATERIALS AND METHODS Adult male Sprague-Dawley rats were used to assess the effects of NMDA receptor antagonists (MK-801, memantine or LY235959) on tolerance and sensitization to three opiates: morphine, methadone, or buprenorphine. It was predicted that low, selective doses of the antagonists would inhibit the development of opiate tolerance and sensitization. RESULTS Consistent with our predictions, the noncompetitive NMDA receptor antagonists MK-801 and memantine and the competitive NMDA receptor antagonist LY235959 inhibited the development of sensitization to the locomotor stimulant effect of morphine. Additionally, MK-801 inhibited the development of tolerance and sensitization to methadone and buprenorphine in a similar manner. CONCLUSIONS The results, together with previous research, suggest that NMDA receptors are broadly involved in opiate-induced plasticity, including the development of opiate tolerance and sensitization.
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Affiliation(s)
- Ian A Mendez
- Department of Psychology, Texas A & M University, College Station, TX 77843, USA.
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Trevisan L, Petrakis IL, Pittman B, Gueorguieva R, D’Souza DC, Perry E, Limoncelli D, Krystal JH. Absence of Significant Interactive Effects of High-Dose d-Cycloserine and Ethanol in Healthy Human Subjects: Preliminary Insights Into Ethanol Actions at the GlycineB Site of NMDA Glutamate Receptors. Alcohol Clin Exp Res 2007; 32:36-42. [DOI: 10.1111/j.1530-0277.2007.00543.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Sheng Z, Dai Q, Prorok M, Castellino FJ. Subtype-selective antagonism of N-methyl-D-aspartate receptor ion channels by synthetic conantokin peptides. Neuropharmacology 2007; 53:145-56. [PMID: 17588620 PMCID: PMC3965200 DOI: 10.1016/j.neuropharm.2007.04.016] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 03/28/2007] [Accepted: 04/25/2007] [Indexed: 01/29/2023]
Abstract
Conantokin-G (con-G), conantokin-T (con-T), a truncated conantokin-R (con-R[1-17]), that functions the same as wild-type con-R, and variant sequences of con-T, were chemically synthesized and employed to investigate their selectivities as antagonists of glutamate/glycine-evoked ion currents in human embryonic kidney-293 cells expressing various combinations of NMDA receptor (NMDAR) subunits (NR), viz., NR1a/2A, NR1a/2B, NR1b/2A and NR1b/2B. Con-G did not substantially affect ion flow into NR1a,b/NR2A-transfected cells, but potently inhibited cells expressing NR1a,b/NR2B, showing high NR2B selectivity. Con-T and con-R served as non-selective antagonists of all of four NMDAR subunit combinations. C-terminal truncation variants of the 21-residue con-T were synthesized and examined in this regard. While NMDAR ion channel antagonist activity, and the ability to adopt the Ca(2+)-induced alpha-helical conformation, diminished as a function of shortening the COOH-terminus of con-T, NMDAR subtype selectivity was enhanced in the con-T[1-11], con-T[1-9], and con-T[1-8] variants toward NR2A, NR1b, and NR1b/2A, respectively. Receptor subtype selectivity was also obtained with Met-8 sequence variants of con-T. Con-T[M8A] and con-T[M8Q] displayed selectivity with NR2B-containing subunits, while con-T[M8E] showed enhanced activity toward NR1b-containing NMDAR subtypes. Of those studied, the most highly selective variant was con-T[M8I], which showed maximal NMDAR ion channel antagonism activity toward the NR1a/2A subtype. These studies demonstrate that it is possible to engineer NMDAR subtype antagonist specificity into con-T. Since the subunit composition of the NMDAR varies temporally and spatially in developing brain and in various disease states, conantokins with high subtype selectivities are potentially valuable drugs that may be used at specific stages of disease and in selected regions of the brain.
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Affiliation(s)
- Zhenyu Sheng
- W.M. Keck Center for Transgene Research, 230 Raclin-Carmichael Hall, University of Notre Dame, Notre Dame, IN 46556, USA
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Evans SM, Levin FR, Brooks DJ, Garawi F. A pilot double-blind treatment trial of memantine for alcohol dependence. Alcohol Clin Exp Res 2007; 31:775-82. [PMID: 17378918 DOI: 10.1111/j.1530-0277.2007.00360.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND There is growing evidence that N-methyl-d-aspartate (NMDA) receptor antagonists may have potential for the treatment of alcohol disorders. Memantine is a selective noncompetitive NMDA receptor antagonist that has been shown to decrease alcohol craving in moderate drinkers. This 16-week double-blind outpatient pilot clinical trial determined if memantine was more effective than placebo at reducing alcohol use in actively drinking alcohol-dependent patients. METHODS Forty-four treatment-seeking alcohol-dependent individuals were enrolled, with 34 patients stratified to either the memantine group (n=19; maximum dose of 40 mg/d) or the placebo (PBO; n=15) group. The primary outcome measures were related to alcohol use (average drinks per day, average drinks per drinking day, percentage of heavy drinking days, and percentage of days abstinent) based on the timeline follow-back (TLFB). Secondary outcome measures included the Obsessive Compulsive Drinking Scale, Clinical Global Impression ratings, and gamma-glutamyltransferase (GGT), a biomarker of recent alcohol use. To enhance retention, patients received voucher incentives for clinic attendance. RESULTS Of those randomized, approximately 80% (27) completed the entire 16-week trial. Longitudinal analysis of drinks per day and drinks per drinking day showed a significant reduction in alcohol use, but no difference between the 2 groups. Further, the percentage of heavy drinking days indicated that both groups showed a significant decrease in drinking behavior, but there was significant treatment effect in favor of the PBO group. Similarly, for the percentage of days abstinent, the PBO group achieved a significantly greater percentage of days abstinent at a faster rate than the memantine group. Lastly, the memantine group reported a greater number of side effects compared with the PBO group, such that 26% of patients had their drug dose decreased or discontinued due to memantine-related side effects. CONCLUSIONS The results of this double-blind placebo-controlled pilot trial do not support the use of memantine for the treatment of actively drinking alcohol-dependent patients. However, voucher incentives did facilitate retention.
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Affiliation(s)
- Suzette M Evans
- New York State Psychiatric Institute, New York, New York 10032, USA.
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Rezayof A, Golhasani-Keshtan F, Haeri-Rohani A, Zarrindast MR. Morphine-induced place preference: Involvement of the central amygdala NMDA receptors. Brain Res 2007; 1133:34-41. [PMID: 17184750 DOI: 10.1016/j.brainres.2006.11.049] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Revised: 11/05/2006] [Accepted: 11/16/2006] [Indexed: 11/21/2022]
Abstract
In the present study, the effects of bilateral injections of N-methyl-d-aspartate (NMDA) receptor agonist and/or antagonist into the central amygdala (CeA) on the acquisition and expression of morphine-induced conditioned place preference (CPP) were investigated in male Wistar rats. Animals that received 3 daily subcutaneous (s.c.) injections of morphine (1-9 mg/kg) or saline (1.0 ml/kg) indicated a significant preference for compartment paired with morphine in a dose dependent manner. Intra-CeA administration of the NMDA (0.01, 0.1 or 1 microg/rat) with an ineffective dose of morphine (1 mg/kg, s.c.) elicited a significant CPP. Administration of the non-competitive NMDA receptor antagonist, MK-801 (0.1, 0.3 or 0.5 microg/rat), into the central amygdala dose-dependently inhibited the morphine (6 mg/kg, s.c.)-induced place preference. Furthermore, intra-CeA administration of MK-801 (0.25, 0.5 or 1 microg/rat) reduced the response induced by NMDA (1 microg/rat, intra-CeA) plus morphine (1 mg/kg, s.c.). Neither NMDA nor MK-801 alone produce a significant place preference or place aversion. Moreover, intra-CeA injection of NMDA but not MK-801 before testing significantly increased the expression of morphine (6 mg/kg, s.c.)-induced place preference. NMDA or MK-801 injections into the CeA had no effects on locomotor activity on the testing sessions. These results suggest that the NMDA receptor mechanisms in the central amygdala may be involved in the acquisition and expression of morphine-induced place preference.
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Affiliation(s)
- Ameneh Rezayof
- School of Biology, University College of Science, University of Tehran, P. O. Box 14155-6455, Tehran, Iran.
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Biegon A, Gibbs A, Alvarado M, Ono M, Taylor S. In vitro and in vivo characterization of [3H]CNS-5161—A use-dependent ligand for theN-methyl-d-aspartate receptor in rat brain. Synapse 2007; 61:577-86. [PMID: 17455246 DOI: 10.1002/syn.20400] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Glutamate is the major excitatory neurotransmitter in the brain. Glutamate activation of the N-methyl-D-aspartate (NMDA) receptor subtype is thought to mediate important physiological and pathological processes, including memory formation and excitotoxicity. The goal of the present work was to characterize and validate a candidate agent for noninvasive positron emission tomography (PET) imaging of this receptor. [(3)H]-labeled N-[3-(3)H]-methyl-3-(thiomethylphenyl)cyanamide (CNS-5161) was incubated with rat brain homogenates at increasing concentrations, temperatures, and times to establish the binding kinetics and affinity of the ligand in vitro. Nonspecific binding was measured with 100 microM MK-801. The compound was also injected i.v. in rats pretreated with saline, NMDA, MK801, or a combination, and organ and brain regional uptake was assessed at various times after injection by autoradiography or dissection. Blood and brain samples were assayed for metabolites by high-performance liquid chromatography. CNS-5161 binds brain membranes with high affinity (K(d) < 4 nM) and fast association and dissociation kinetics. Specific binding increased in the presence of glutamate and glycine. Intravenous administration in control rats resulted in a heterogeneous brain distribution with hippocampus and cortex > thalamus > striatum > cerebellum, and a cortex/cerebellum ratio of 1.4. Pretreatment with NMDA increased the hippocampus-to-cerebellum ratio to 1.6-1.9 while MK801 abolished this increase, resulting in ratios close to 1. Thus, CNS-5161 binds preferentially to the activated state of the NMDA receptor channel in vitro and in vivo. The high affinity and fast kinetics make it compatible with PET imaging of a carbon-11 labeled CNS-5161.
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Affiliation(s)
- Anat Biegon
- Medical Department, Brookhaven National Laboratory, Upton, New York, USA.
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Ma YY, Guo CY, Yu P, Lee DYW, Han JS, Cui CL. The role of NR2B containing NMDA receptor in place preference conditioned with morphine and natural reinforcers in rats. Exp Neurol 2006; 200:343-55. [PMID: 16631172 DOI: 10.1016/j.expneurol.2006.02.117] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Revised: 01/23/2006] [Accepted: 02/16/2006] [Indexed: 10/24/2022]
Abstract
It has been reported that N-methyl-D-aspartate (NMDA) receptor is implicated in drug addiction and antagonists of the NMDA receptor complex can inhibit the development and expression of conditioned place preference (CPP) induced by several addictive drugs, implying that this class of compounds might be considered as candidate for the treatment of substance abuse. To explore this possibility, it is important to evaluate whether the inhibitory effect of NMDA receptor antagonists would be confined to behaviors produced by drugs of abuse only, but not by natural reinforcers. According to the quantitative changes of NMDA receptor subunits, including NR1, NR2A, and NR2B, induced by diverse types of reinforcers, we chose NR2B subunit as the target of research. Experimental results showed that (1) an augmented expression of NR2B subunit was revealed by Western blotting in the nucleus accumbens (NAc) and the hippocampus in rats with CPP induced by morphine, but not by natural rewards such as food, novel environment and social interaction. (2) Ifenprodil, an antagonist highly selective for NR2B subunit of the NMDA receptor, produced a dose-dependent reduction in CPP induced by morphine and novel environment, but not that by food consumption and social interaction. Taking together, these findings suggested that NR2B containing NMDA receptor may be more involved with morphine reward rather than natural rewards, and that antagonism of NR2B may have a potential for the treatment of morphine abuse.
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Affiliation(s)
- Yao-Ying Ma
- Neuroscience Research Institute and Department of Neurobiology, Peking University Health Science Center, Key Laboratory of Neuroscience, The Ministry of Education and Ministry of Public Health, 38 Xueyuan Road, Beijing 100083, PR China
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Prescot AP, de B Frederick B, Wang L, Brown J, Jensen JE, Kaufman MJ, Renshaw PF. In vivo detection of brain glycine with echo-time-averaged (1)H magnetic resonance spectroscopy at 4.0 T. Magn Reson Med 2006; 55:681-6. [PMID: 16453318 DOI: 10.1002/mrm.20807] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) method is described that enables the in vivo measurement of endogenous brain glycine (Gly) levels in human subjects. At 4.0 T, TE-averaging (1)H-MRS dramatically attenuates the overlapping myo-inositol (mI) resonances at 3.52 ppm, permitting a more reliable measure of the Gly singlet peak. This methodology initially is described and tested in phantoms. The phantom data infers that the 3.55-ppm peak predominantly is Gly with a smaller contribution from mI. The composite resonance thus is differentiated from pure Gly and mI and is labeled Gly*. The mI contribution was calculated as <2% of the total Gly* signal for a 1:1 mI/Gly mixture. The technique subsequently was used to acquire TE-averaged (1)H-MRS data from the occipital cortex of healthy control subjects. The resultant spectra closely resembled experimental phantom data. LC-model analysis provided a means for quantifying TE-averaged (1)H-MRS spectra and a mean test-retest variability measure of 15% was established for brain Gly* levels in studies of six healthy subjects.
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Affiliation(s)
- Andrew P Prescot
- Brain Imaging Center, McLean Hospital, Belmont, Massachusetts 02478, USA.
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Newman JL, Beardsley PM. Effects of memantine, haloperidol, and cocaine on primary and conditioned reinforcement associated with cocaine in rhesus monkeys. Psychopharmacology (Berl) 2006; 185:142-9. [PMID: 16425059 DOI: 10.1007/s00213-005-0282-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2005] [Accepted: 11/27/2005] [Indexed: 10/25/2022]
Abstract
RATIONALE The N-methyl-D-aspartate (NMDA) receptor has been implicated in mediating the reinforcing effects of abused drugs. Some reports indicate the uncompetitive NMDA antagonist, memantine, modulates the conditioned and unconditioned effects of stimulants in rats. OBJECTIVE The objective of this study was to evaluate the effects of memantine on the primary and conditioned reinforcing effects of cocaine in the rhesus monkey. METHODS Rhesus monkeys were trained to press levers reinforced with either cocaine-associated stimuli (brief stimuli, BS) or 30-microg/kg cocaine infusion during daily, 75-min experimental sessions in which the reinforcers were independently available in separate components according to identical progressive ratio (PR) schedules. Memantine (0.3-10 mg/kg), and as comparators, haloperidol (0.001-0.1 mg/kg) and cocaine (0.01-1 mg/kg), were administered 5 min before experimental sessions. RESULTS Memantine (0.3-3 mg/kg) produced decreases in responding maintained by BS presentations at some doses which failed to affect cocaine self-administration when measured during equivalent periods early in the experimental session. Memantine (3 mg/kg) increased cocaine self-administration, however, later in the session. A low dose of haloperidol (0.001 mg/kg) increased the number of BS presentations, whereas higher doses decreased their number. Cocaine self-administration was not significantly affected by haloperidol until a behaviorally suppressant dose (0.1 mg/kg) was administered. Pretreatment with high doses of cocaine (0.3 and 1 mg/kg) decreased responding maintained by both reinforcers. CONCLUSION These results suggest that while memantine may attenuate the conditioned reinforcing effects of cocaine-associated stimuli, it may also occasion increase levels of cocaine self-administration. These findings support the hypothesis that the NMDA receptor can play a role in modulating the conditioned and primary reinforcing effects of cocaine.
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Affiliation(s)
- Jennifer L Newman
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, P.O. Box 980613, Richmond, VA 23298, USA
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Yonghui L, Xigeng Z, Yunjing B, Xiaoyan Y, Nan S. Opposite effects of MK-801 on the expression of food and morphine-induced conditioned place preference in rats. J Psychopharmacol 2006; 20:40-6. [PMID: 16174676 DOI: 10.1177/0269881105057250] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Behavioural studies have provided strong evidence for common substrates in the rewards of natural and addictive substances, but it is still unclear whether there is a common glutamatergic NMDA receptor mechanism involved in the processing of reward for both. The present study was designed to investigate the effects of MK-801 (0.1mg/kg) on the expression of place preference conditioned with food and morphine (5.0mg/kg) in rats. The data indicates that MK-801 potentiates the expression of food-induced conditioned place preference (CPP) but retards that of morphine CPP. It also demonstrates that the opposite effects of MK-801 on food and morphine CPP expression were caused neither by hyperactivity nor by the impairment of memory retrieval. These results suggest that MK-801 enhances food craving and inhibits morphine craving in rats, and that the roles of glutamatergic NMDA receptor mechanisms in the reward processing of natural reinforcers and addictive drugs may be dissociable.
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Affiliation(s)
- Li Yonghui
- Institute of Psychology, Chinese Academy of Sciences; Laboratory of Mental Health, Chinese Academy of Sciences, P.R. China.
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Abstract
Protection of abstinent individuals from relapse is the main goal of drug dependence treatment. Relapse is frequently precipitated by exposure to small doses of the drug of abuse or exposure to the environment that was previously associated with the drug. Mice exposed to morphine (10 mg/kg) in a unique test-box environment display a conditioned place preference for this environment. Such preference can be extinguished by subsequent pairing of physiological saline administration with the same environment. Once extinguished, the original place preference can be reinstated after a priming dose (1-2.5 mg/kg) of morphine is given. However, mice treated with 7.5 (but not 3.75) mg/kg of memantine (the glutamate/NMDA receptor antagonist) during the extinction phase were insensitive to morphine's ability to reinstate the place preference 2 days after extinction conditionings. Effect of memantine was also observed when priming dose of morphine was given 21 days after extinction conditionings. In contrast, morphine's ability to reinstate conditioned response was not affected by treatment with 10 mg/kg of chlordiazepoxide, 0.5 mg/kg of LSD-25, or 1 mg/kg of morphine given during extinction conditionings. A separate experiment demonstrated that memantine (7.5 mg/kg) treatment did not affect learning. We show for the first time that memantine treatment during extinction conditionings may abolish the ability of drug-related cues to evoke reinstatement, suggesting that this NMDA receptor antagonist can be useful in preventing relapse in opioid dependent individuals.
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Affiliation(s)
- Piotr Popik
- Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland.
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