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Le Roux M, Möller M, Harvey BH. Prolonged efavirenz exposure reduces peripheral oxytocin and vasopressin comparable to known drugs of addiction in male Sprague Dawley rats. IBRO Neurosci Rep 2021; 11:56-63. [PMID: 34939063 PMCID: PMC8664698 DOI: 10.1016/j.ibneur.2021.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 03/03/2021] [Accepted: 06/22/2021] [Indexed: 11/27/2022] Open
Abstract
Introduction Several drugs of abuse (DOA) are capable of modulating neurohypophysial hormones, such as oxytocin (OT) and vasopressin (VP), potentially resulting in the development of psychological abnormalities, such as cognitive dysfunction, psychoses, and affective disorders. Efavirenz (EFV), widely used in Africa and globally to treat HIV, induces diverse neuropsychiatric side effects while its abuse has become a global concern. The actions of EFV may involve neurohypophysial system (NS) disruption like that of known DOA. This study investigated whether sub-chronic EFV exposure, at a previously-determined rewarding dose, alters peripheral OT and VP levels versus that of a control, ∆9-tetrahydrocannabinol (∆9-THC), methamphetamine (MA) and cocaine. Materials and methods To simulate the conditions under which reward-driven behavior had previously been established for EFV, male Sprague Dawley rats (n = 16/exposure) received intraperitoneal vehicle (control) or drug administration across an alternating sixteen-day dosing protocol. Control administration (saline/olive oil; 0.2 ml) occurred on odd-numbered and drug administration (EFV: 5 mg/kg, ∆9-THC: 0.75 mg/kg, MA: 1 mg/kg, or cocaine: 20 mg/kg) on even-numbered days followed by euthanasia, trunk blood collection and plasma extraction for neuropeptide assay. Effect of drug exposure on peripheral OT and VP levels was assessed versus controls and quantified using specific ELISA kits. Statistical significance was determined by Kruskal-Wallis ANOVA, with p < 0.05. Ethics approval: NWU-00291-17-A5. Results Delta-9-THC reduced OT and VP plasma levels (p < 0.0001, p = 0.0141; respectively), cocaine reduced plasma OT (p = 0.0023), while MA reduced plasma VP levels (p = 0.0001), all versus control. EFV reduced OT and VP plasma levels (p < 0.0001; OT and VP) versus control, and similar to ∆9-THC. Conclusion EFV markedly affects the NS in significantly reducing both plasma OT and VP equivalent to DOA. Importantly, EFV has distinct effects on peripheral OT and VP levels when assessed within the context of drug dependence. The data highlights a possible new mechanism underlying previously documented EFV-induced effects in rats, and whereby EFV may induce neuropsychiatric adverse effects clinically; also providing a deeper understanding of the suggested abuse-potential of EFV.
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Key Words
- 5-HT, 5-hydroxytryptamine (serotonin)
- ADH, antidiuretic hormone
- AEA, N-arachidonoylethanolamine (anandamide)
- ANOVA, one-way analysis of variance
- ARRIVE, animal research: reporting of in vivo experiments (guidelines)
- ARV, antiretroviral
- Ach, acetylcholine
- CB, cannabinoid
- CNS, central nervous system
- CPP, conditioned place preference
- Cocaine
- DA, dopamine
- DAT, dopamine transporter
- DOA‘s, drug(s) of abuse
- ECS, endocannabinoid system
- EFV, efavirenz
- ELISA, enzyme-linked immunosorbent assay
- Efavirenz
- GABA, gamma-aminobutyric acid
- Glu, glutamate
- HIV, human immunodeficiency virus
- HNS, hypothalamic neurohypophysial system
- HPA, hypothalamic-pituitary-adrenal (axis)
- IP, intraperitoneal
- IV, intravenous
- M, muscarinic
- MA, methamphetamine
- MAO, monoamine oxidase
- Methamphetamine
- NAc, nucleus accumbens
- NE, norepinephrine
- NO, nitric oxide
- NPAE, neuropsychiatric adverse effect
- OT, oxytocin
- OTR, oxytocin receptor
- Oxytocin
- PND, postnatal day
- PVN, paraventricular nucleus
- SC, subcutaneous
- SD, Sprague Dawley (rat)
- SEM, standard error of the mean
- SERT, serotonin transporter
- SON, supraoptic nucleus
- VMAT, vesicular monoamine transporter
- VP, vasopressin
- VPR, vasopressin receptor
- Vasopressin
- cART, combined antiretroviral therapy
- ∆9-THC, delta-9-tetrahydrocannabinol
- ∆9-tetrahydrocannabinol
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Affiliation(s)
- Mandi Le Roux
- Division of Pharmacology, School of Pharmacy, North-West University, Potchefstroom, South Africa.,Centre of Excellence for Pharmaceutical Sciences (PharmaCenTM), School of Pharmacy, North-West University, Potchefstroom, South Africa
| | - Marisa Möller
- Division of Pharmacology, School of Pharmacy, North-West University, Potchefstroom, South Africa.,Centre of Excellence for Pharmaceutical Sciences (PharmaCenTM), School of Pharmacy, North-West University, Potchefstroom, South Africa
| | - Brian H Harvey
- Division of Pharmacology, School of Pharmacy, North-West University, Potchefstroom, South Africa.,Centre of Excellence for Pharmaceutical Sciences (PharmaCenTM), School of Pharmacy, North-West University, Potchefstroom, South Africa
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Tapias-Espinosa C, Cañete T, Sampedro-Viana D, Brudek T, Kaihøj A, Oliveras I, Tobeña A, Aznar S, Fernández-Teruel A. Oxytocin attenuates schizophrenia-like reduced sensorimotor gating in outbred and inbred rats in line with strain differences in CD38 gene expression. Physiol Behav 2021; 240:113547. [PMID: 34364851 DOI: 10.1016/j.physbeh.2021.113547] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 07/06/2021] [Accepted: 08/01/2021] [Indexed: 11/30/2022]
Abstract
Prepulse inhibition (PPI) of the startle response is a measure of sensorimotor gating that is impaired in many clinical conditions, including schizophrenia. The inbred Roman high-avoidance (RHA) rats, compared to their low-avoidance (RLA) counterparts, show distinct schizophrenia-like phenotypes, such as spontaneous deficits in PPI accompanied by decreased medial prefrontal cortex (mPFC) activity and volume. Schizophrenia-like deficits are usually attenuated by antipsychotic drugs, but these drugs often produce severe side effects. In order to reduce these side effects, the neuropeptide oxytocin has been proposed as an alternative natural antipsychotic for schizophrenia. Here, we examined the effects of peripheral oxytocin administration (saline, 0.04, and 0.2 mg/kg) on PPI in the RHA vs. RLA rats, as well as in the outbred heterogeneous stock (HS) rats. Our results showed that oxytocin increased PPI in the HS rats and attenuated PPI deficits in the RHA rats, but it did not significantly affect PPI in the RLAs. To explore whether these divergent effects were associated with differences in oxytocinergic mechanisms, we analyzed gene expression of the oxytocin receptor (OXTR) and the regulator of oxytocin release (CD38) in the mPFC of the Roman rats. Consistent with the differential oxytocin effects on PPI (RHA > RLA), constitutive CD38 expression was reduced in the RHA rats compared to the RLAs, while oxytocin administration increased OXTR expression in both strains. Overall, the present work reveals that oxytocin administration shows antipsychotic-like effects on PPI in outbred and inbred rats, and it suggests that these effects may be related to basal differences in oxytocin-mediated mechanisms in the mPFC.
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Affiliation(s)
- Carles Tapias-Espinosa
- Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, Barcelona, Spain.
| | - Toni Cañete
- Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Daniel Sampedro-Viana
- Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Tomasz Brudek
- Research Laboratory for Stereology and Neuroscience, Bispebjerg-Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark; Copenhagen Center for Translational Research, Bispebjerg-Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Anna Kaihøj
- Research Laboratory for Stereology and Neuroscience, Bispebjerg-Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark; Copenhagen Center for Translational Research, Bispebjerg-Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark
| | - Ignasi Oliveras
- Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Adolf Tobeña
- Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Susana Aznar
- Research Laboratory for Stereology and Neuroscience, Bispebjerg-Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark; Copenhagen Center for Translational Research, Bispebjerg-Frederiksberg Hospital, University Hospital of Copenhagen, Copenhagen, Denmark.
| | - Alberto Fernández-Teruel
- Department of Psychiatry & Forensic Medicine, Institute of Neurosciences, Universitat Autònoma de Barcelona, Barcelona, Spain.
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Sundar M, Patel D, Young Z, Leong KC. Oxytocin and Addiction: Potential Glutamatergic Mechanisms. Int J Mol Sci 2021; 22:ijms22052405. [PMID: 33673694 PMCID: PMC7957657 DOI: 10.3390/ijms22052405] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/25/2021] [Accepted: 02/25/2021] [Indexed: 11/16/2022] Open
Abstract
Recently, oxytocin (OXT) has been investigated for its potential therapeutic role in addiction. OXT has been found to diminish various drug-seeking and drug-induced behaviors. Although its behavioral effects are well-established, there is not much consensus on how this neuropeptide exerts its effects. Previous research has given thought to how dopamine (DA) may be involved in oxytocinergic mechanisms, but there has not been as strong of a focus on the role that glutamate (Glu) has. The glutamatergic system is critical for the processing of rewards and the disruption of glutamatergic projections produces the behaviors seen in drug addicts. We introduce the idea that OXT has direct effects on Glu transmission within the reward processing pathway. Thus, OXT may reduce addictive behaviors by restoring abnormal drug-induced changes in the glutamatergic system and in its interactions with other neurotransmitters. This review offers insight into the mechanisms through which a potentially viable therapeutic target, OXT, could be used to reduce addiction-related behaviors.
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Uskur T, Şenöz AÖ, Çevreli B, Barlas A, Uzbay T. Propofol but not dexmedetomidine produce locomotor sensitization via nitric oxide in rats. Psychopharmacology (Berl) 2021; 238:569-577. [PMID: 33169201 DOI: 10.1007/s00213-020-05707-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/04/2020] [Indexed: 11/24/2022]
Abstract
RATIONALE The abused potential of some anesthetics has been debated. Measurement of locomotor sensitization is a better way to detect the neurobehavioral plasticity of addiction. OBJECTIVES The present study aims to explore whether propofol and dexmedetomidine are capable of inducing locomotor sensitization. METHODS Male Wistar rats (250-300 g) were the subjects (n = 8 for each group). Propofol (20 and 40 mg/kg) and dexmedetomidine (2.5-20 μg/kg) or saline were injected to rats intraperitoneally (IP), and their locomotor activities were recorded for 15 min. Consequently, L-NAME (30 and 60 mg/kg)-a nitric oxide (NO) inhibitory agent-was injected to rats 30 min before propofol (40 mg/kg) or saline injections, and the locomotor activity was recorded. The process was carried out for 13 days, with 7 sessions applied every other day. RESULTS Dexmedetomidine did not produce any significant locomotor sensitization. While propofol (20 mg/kg) produced a significant locomotor sensitization in the last treatment session (day 13), at the higher dose, it prompted a significant locomotor sensitization from the 3rd treatment session. L-NAME blocked propofol-induced locomotor hyperactivity and sensitization significantly without producing any noteworthy changes on the locomotor activity during the testing period of 13 days when administered alone. CONCLUSIONS Our results suggest that propofol but not dexmedetomidine produced a significant locomotor sensitization via central nitrergic system. Dexmedetomidine may have a lesser psychostimulant type addictive potential than propofol. Sensitization development by propofol implies that this drug might be effective on the neuroadaptive processes associated with a stimulant type of dependence.
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Affiliation(s)
- Tuğçe Uskur
- Faculty of Medicine, Department of Medical Pharmacology, Beykent University, Istanbul, Turkey
| | - Ayşe Özçetin Şenöz
- Neuropsychopharmacology Application and Research Center (NPFUAM), Üsküdar University, Istanbul, Turkey
| | - Burcu Çevreli
- Neuropsychopharmacology Application and Research Center (NPFUAM), Üsküdar University, Istanbul, Turkey
| | - Aydın Barlas
- School of Medicine, Department of Pharmacology, Altınbaş University, İstanbul, Turkey
| | - Tayfun Uzbay
- Neuropsychopharmacology Application and Research Center (NPFUAM), Üsküdar University, Istanbul, Turkey.
- Faculty of Medicine, Department of Medical Pharmacology, Üsküdar University, İstanbul, Turkey.
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Tsuji T, Inatani M, Tsuji C, Cheranov SM, Kadonosono K. Oxytocin induced epithelium-mesenchimal transition through Rho-ROCK pathway in ARPE-19 cells, a human retinal pigmental cell line. Tissue Cell 2020; 64:101328. [PMID: 32473703 DOI: 10.1016/j.tice.2019.101328] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 12/30/2019] [Accepted: 12/30/2019] [Indexed: 12/12/2022]
Abstract
Previous reports suggest that oxytocin receptors (OXTRs) are expressed in the retinal pigment epithelium in primates. Oxytocinergic signaling activates the Rho-ROCK pathway, which reorganizes the actin cytoskeleton and alters other cellular biophysical characteristics. Such changes could be involved in the epithelial-mesenchymal transition and development of proliferative vitreous retinopathy. Here, we investigated whether oxytocin (OXT) binding to OXTRs in the retinal pigment epithelium can induce Rho-ROCK-mediated cellular activity. We performed four different assays of Rho-ROCK signaling in a human retinal pigment epithelium cell line (ARPE-19) such as induction of actin fibers, wound healing, cell growth, and collagen gel contraction. The assays were performed with or without OXT (100 nM) exposure, as well as with exposure to ripasudil, a specific ROCK inhibitor. The actin stress fiber formation, a phenotype mediated by activated Rho GTPase, was induced by OXT. OXT also accelerated wound closure 19 h after administration, increased cell growth 24 h afterwards, and induced stronger collagen gel contractions. All four cellular responses were inhibited with the addition of 50 μM ripasudil. Taken together, OXT-mediated activation of Rho-ROCK signal transduction could play a role in regulating epithelial-mesenchymal transition in the retinal pigment epithelium, and increase the possibility of subsequent proliferative vitreous retinopathy after vitrectomy.
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Affiliation(s)
- Takahiro Tsuji
- Department of Ophthalmology, Faculty of Medical Sciences, Fukui University, 23-3 Shimoaizuki, Matsuoka, Eiheiji, Yoshida, Fukui, 910-1193, Japan; Department of Ophthalmology & Micro-technology, Yokohama City University, Medical School, Yokohama City University, Medical School, 4-57 Urafune-cho Minami-ku, Yokohama City, 232-0024, Japan.
| | - Masaru Inatani
- Department of Ophthalmology, Faculty of Medical Sciences, Fukui University, 23-3 Shimoaizuki, Matsuoka, Eiheiji, Yoshida, Fukui, 910-1193, Japan
| | - Chiharu Tsuji
- Department of Basic Research on Social Recognition and Memory, Research Center for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Stanislav M Cheranov
- Department of Basic Research on Social Recognition and Memory, Research Center for Child Mental Development, Kanazawa University, Kanazawa, 920-8640, Japan
| | - Kazuaki Kadonosono
- Department of Ophthalmology & Micro-technology, Yokohama City University, Medical School, Yokohama City University, Medical School, 4-57 Urafune-cho Minami-ku, Yokohama City, 232-0024, Japan
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6
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Lee MR, Rohn MC, Zanettini C, Coggiano MA, Leggio L, Tanda G. Effect of systemically administered oxytocin on dose response for methylphenidate self-administration and mesolimbic dopamine levels. Ann N Y Acad Sci 2019; 1455:173-184. [PMID: 31074517 PMCID: PMC10014164 DOI: 10.1111/nyas.14101] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 03/01/2019] [Accepted: 03/27/2019] [Indexed: 11/29/2022]
Abstract
The neuropeptide oxytocin (OT) alters behaviors related to the administration of drugs of abuse, including stimulants. OT also plays a key role in social bonding, which involves an interaction between OT and dopamine (DA) in the nucleus accumbens (NAc). The nature of the interaction between OT and DA in the striatum in the context of psychostimulants is unclear. We investigated the effect of OT, delivered intraperitoneally, on the methylphenidate (MP) dose-response function for self-administration in rats. Food was used as a control condition. In a microdialysis study, we measured the effect of intraperitoneal OT on MP-stimulated striatal DA levels. Systemic OT pretreatment caused a downward shift in the MP dose-response function for self-administration, while having no effect on motor activity. OT also caused a reduction in food self-administration, although a significantly higher dose of OT was required for this effect compared with that required for a reduction of MP self-administration. Systemic OT pretreatment caused a potentiation of MP-stimulated DA levels in the NAc shell but not in the core. The significance of these findings is discussed, including the potential of OT as a therapeutic agent for addictive disorders.
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Affiliation(s)
- Mary R. Lee
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Basic Research and National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Bethesda, MD
| | - Matthew C.H. Rohn
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Basic Research and National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Bethesda, MD
| | - Claudio Zanettini
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
| | - Mark A. Coggiano
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
| | - Lorenzo Leggio
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacology, National Institute on Alcohol Abuse and Alcoholism Division of Intramural Clinical and Basic Research and National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Bethesda, MD
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
- Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University, Providence, RI
| | - Gianluigi Tanda
- Medications Development Program, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse Intramural Research Program, National Institutes of Health, Baltimore, MD
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Zhang TY, Shahrokh D, Hellstrom IC, Wen X, Diorio J, Breuillaud L, Caldji C, Meaney MJ. Brain-Derived Neurotrophic Factor in the Nucleus Accumbens Mediates Individual Differences in Behavioral Responses to a Natural, Social Reward. Mol Neurobiol 2019; 57:290-301. [PMID: 31327126 DOI: 10.1007/s12035-019-01699-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 07/09/2019] [Indexed: 01/17/2023]
Abstract
BDNF-oxytocin interactions in the brain are implicated in mammalian maternal behavior. We found that BDNF gene expression is increased in the hippocampus of rat mothers that show increased pup licking/grooming (high LG mothers) compared to low LG mothers. High LG mothers also showed increased BDNF protein levels in the nucleus accumbens (nAcc). Immunoneutralization of BDNF in the nAcc eliminated the differences in pup LG between high and low LG mothers. Oxytocin antagonist in the ventral hippocampus significantly decreased the frequency of maternal LG behavior. Oxytocin antagonist significantly prevented the oxytocin-induced BDNF gene expression in primary hippocampal cell cultures. We suggest that oxytocin-induced regulation of BDNF in the nAcc provides a neuroendocrine basis for both individual differences in maternal behavior and resilience to the stress of reproduction in female mammals.
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Affiliation(s)
- Tie-Yuan Zhang
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada. .,Sackler Program for Epigenetics & Psychobiology at McGill University, Montreal, Quebec, H4H1R3, Canada. .,Ludmer Centre for Neuroinformatics and Mental health, McGill University, Montreal, Quebec, H4H1R3, Canada.
| | - Dara Shahrokh
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada
| | - Ian C Hellstrom
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada
| | - Xianglan Wen
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada.,Sackler Program for Epigenetics & Psychobiology at McGill University, Montreal, Quebec, H4H1R3, Canada
| | - Josie Diorio
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada.,Sackler Program for Epigenetics & Psychobiology at McGill University, Montreal, Quebec, H4H1R3, Canada
| | - Lionel Breuillaud
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada
| | - Christian Caldji
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada
| | - Michael J Meaney
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, Quebec, H4H1R3, Canada. .,Sackler Program for Epigenetics & Psychobiology at McGill University, Montreal, Quebec, H4H1R3, Canada. .,Ludmer Centre for Neuroinformatics and Mental health, McGill University, Montreal, Quebec, H4H1R3, Canada. .,Singapore Institute for Clinical Sciences, Singapore, 117609, Singapore.
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Abstract
The neuropeptide Oxytocin (ΟΤ) is involved as a neurohormone, a neurotransmitter, or a neuromodulator in an extensive range of central and peripheral effects, complex emotional and social human behaviors, memory and learning processes. It is implicated in homeostatic, neuroadaptive processes associated with stress responses and substance use via interactions with the hypothalamic-pituitary-adrenal (HPA) axis and the dopamine mesolimbic reward stress system. This chapter reviews the preclinical and clinical literature on the complicated relationships between endogenous and exogenous opioids and ΟΤ systems and attempts to highlight key findings to date on the effectiveness of intranasal OT administration to treat opioid use disorders. OΤ seems to attenuate, even inhibit, the development of opioid use disorders in preclinical models but is still under clinical research as a promising pharmacological agent in the treatment of opioid use related behaviors. Evidence suggests a role for OT as an adjunctive or stand-alone treatment of behavioral, cognitive and emotional deficits associated with substance use, which may be responsible for seeking behavior and relapse. The mechanisms by which oxytocin acts to reverse the neural substrates of these deficits, partially due to substance induced alterations of the endogenous OT system, and thus modify the behavioral response to substance use are discussed. Other clinically relevant issues are also discussed.
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Chiamulera C, Padovani L, Corsi M. Drug discovery for the treatment of substance use disorders: novel targets, repurposing, and the need for new paradigms. Curr Opin Pharmacol 2017; 35:120-124. [PMID: 28874314 DOI: 10.1016/j.coph.2017.08.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/24/2017] [Accepted: 08/21/2017] [Indexed: 01/13/2023]
Abstract
Drug addiction treatment medications available nowadays are limited in both efficacy and number. The increased understanding of drug addiction circuitries leads the scientific community to look for better molecules and targets for detoxification and relapse prevention. This review focus on known targets (e.g., metabotropic glutamate receptor 5 and GABAB receptor) and on novel potential treatment acting on oxytocin system, which interacts with diverse neurotransmitters, has proved successful in both preclinical and clinical studies on ethanol, cocaine and methamphetamine. A crucial issue is the identification of new investigational paradigms, which may help to predict treatment efficacy and improve effectiveness.
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Affiliation(s)
- Cristiano Chiamulera
- Neuropsychopharmacology Lab, Sezione Farmacologia, Università di Verona, Policlinico GB Rossi, P.le Scuro 10, 37134 Verona, Italy.
| | - Laura Padovani
- Neuropsychopharmacology Lab, Sezione Farmacologia, Università di Verona, Policlinico GB Rossi, P.le Scuro 10, 37134 Verona, Italy
| | - Mauro Corsi
- Center of Drug Discovery & Development, Aptuit s.r.l., via Fleming 4, 37135 Verona, Italy
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Nikolaou K, Kapoukranidou D, Ndungu S, Floros G, Kovatsi L. Severity of Withdrawal Symptoms, Plasma Oxytocin Levels, and Treatment Outcome in Heroin Users Undergoing Acute Withdrawal. J Psychoactive Drugs 2017; 49:233-241. [PMID: 28443705 DOI: 10.1080/02791072.2017.1312644] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Pre-clinical studies show that, following chronic opioid exposure, oxytocin neurons exhibit over-excitation upon withdrawal, causing an increase in oxytocin brain and plasma levels. Relevant clinical data on humans are scarce. This study investigates the opioid withdrawal stress effect on oxytocin plasma levels in humans. We evaluated 57 male chronic heroin users in a residential detoxification program. We determined plasma oxytocin levels by ELISA and measured the stress effects of withdrawal using the COWS scale for opioid withdrawal, the VAS scale for craving, and the Hamilton scales for anxiety and depression on the second day of admission. Out of the 57 patients enrolled in the study, 27 completed the 21-day program, while the remaining 30 dropped out prior to completion. Plasma oxytocin levels were significantly higher in those individuals who dropped out than in those who completed the program. Participants who dropped out at some stage scored higher in the COWS, VAS-Craving, and Hamilton-anxiety scales, indicating a higher stress and explaining the higher oxytocin levels. In addition, plasma oxytocin levels correlated positively with the scores achieved in the COWS and Hamilton-anxiety scales. Higher withdrawal stress levels are associated with higher plasma oxytocin levels and early treatment discharge.
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Affiliation(s)
- Kakia Nikolaou
- a Consultant Psychiatrist, Head of the Addictions Department IANOS , Papanikolaou General Hospital of Thessaloniki-Psychiatric Hospital of Thessaloniki , Thessaloniki , Greece
| | - Dorothea Kapoukranidou
- b Associate Professor, Department of Physiology, School of Medicine , Aristotle University of Thessaloniki , Thessaloniki , Greece
| | - Samuel Ndungu
- c Emeritus Professor, Laboratory of Forensic Medicine and Toxicology, School of Medicine , Aristotle University of Thessaloniki , Thessaloniki , Greece
| | - Georgios Floros
- d Scientific Associate, Second Department of Psychiatry, School of Medicine , Aristotle University of Thessaloniki , Thessaloniki , Greece
| | - Leda Kovatsi
- e Assistant Professor, Laboratory of Forensic Medicine and Toxicology, School of Medicine , Aristotle University of Thessaloniki , Thessaloniki , Greece
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Fang QQ, Wang JL, Tai FD. Effects of cocaine on aggression and associated central ERα and oxytocin expression in ovariectomized and intact mandarin voles. THE EUROPEAN ZOOLOGICAL JOURNAL 2017. [DOI: 10.1080/11250003.2017.1281354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Q. Q. Fang
- College of Life Sciences, Shaanxi Normal University, Xi’an, China
- College of Biological Sciences and Engineering, Beifang University of Nationalities, Yinchuan, China
| | - J. L. Wang
- College of Biological Sciences and Engineering, Beifang University of Nationalities, Yinchuan, China
| | - F. D. Tai
- College of Life Sciences, Shaanxi Normal University, Xi’an, China
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Wang J, Liu C, Ma Y. Parents induced- conditioned place preference and the neuronal expression of oxytocin and tyrosine hydroxylase in preweanling female pups. Behav Brain Res 2016; 317:528-535. [PMID: 27746207 DOI: 10.1016/j.bbr.2016.10.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 10/04/2016] [Accepted: 10/11/2016] [Indexed: 12/12/2022]
Abstract
Parents-offspring bonding is critical for development of offspring in mammals. While it is known that pups stimuli provide rewarding effects on their parents, few studies have assessed whether parental stimuli serve as a reinforcing agent to their pups, and what the neural mechanisms underlying this reward process may be. In addition to maternal care, male ICR mice display pairmate-dependent parental behavior. Using the conditioned place preference (CPP) paradigm, we examined the effects of maternal and paternal conditioning on the postnatal day 17-21 female ICR mice pups, and compared the expression of oxytocin (OT)- and tyrosine hydroxylase (TH)- immunoreactive (IR) neurons. We found that the pups established dam- or sire- induced CPP when using mother conditioning (MC) or father conditioning (FC) alone. However, the pups failed to show any preference when using mother versus father conditioning (MFC). Compared to the control group, the MC and MFC groups displayed more OT-IR neurons in the supraoptic nucleus and more TH-IR neurons in the ventral tegmental area (VTA). The FC group showed more TH-IR neurons in the VTA compared to the control group, but there were no significant differences in OT-IR neurons. These findings indicate that female ICR mice pups may establish mother- or father- induced CPP. The underpinnings of preference for parents are associated with the activity of VTA dopaminergic neurons, and the preference of pups for mother in particular appears to be associated with OT levels.
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Affiliation(s)
- Jianli Wang
- College of Biological Sciences and Engineering, Beifang University of Nationalities, Yinchuan 750021, China.
| | - Chaobao Liu
- College of Biological Sciences and Engineering, Beifang University of Nationalities, Yinchuan 750021, China
| | - Yongping Ma
- College of Biological Sciences and Engineering, Beifang University of Nationalities, Yinchuan 750021, China
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13
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Liu C, Wang J, Zhan B, Cheng G. Neuronal activity and the expression of hypothalamic oxytocin and vasopressin in social versus cocaine conditioning. Behav Brain Res 2016; 310:84-92. [DOI: 10.1016/j.bbr.2016.05.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Revised: 05/01/2016] [Accepted: 05/03/2016] [Indexed: 12/19/2022]
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Zanos P, Georgiou P, Metaxas A, Kitchen I, Winsky-Sommerer R, Bailey A. Region-specific up-regulation of oxytocin receptor binding in the brain of mice following chronic nicotine administration. Neurosci Lett 2015; 600:33-7. [PMID: 26037668 DOI: 10.1016/j.neulet.2015.05.054] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/18/2015] [Accepted: 05/24/2015] [Indexed: 12/25/2022]
Abstract
Nicotine addiction is considered to be the main preventable cause of death worldwide. While growing evidence indicates that the neurohypophysial peptide oxytocin can modulate the addictive properties of several abused drugs, the regulation of the oxytocinergic system following nicotine administration has so far received little attention. Here, we examined the effects of long-term nicotine or saline administration on the central oxytocinergic system using [(125)I]OVTA autoradiographic binding in mouse brain. Male, 7-week old C57BL6J mice were treated with either nicotine (7.8 mg/kg daily; rate of 0.5 μl per hour) or saline for a period of 14-days via osmotic minipumps. Chronic nicotine administration induced a marked region-specific upregulation of the oxytocin receptor binding in the amygdala, a brain region involved in stress and emotional regulation. These results provide direct evidence for nicotine-induced neuroadaptations in the oxytocinergic system, which may be involved in the modulation of nicotine-seeking as well as emotional consequence of chronic drug use.
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Affiliation(s)
- Panos Zanos
- Sleep, Chronobiology & Addiction Group, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH Surrey, UK
| | - Polymnia Georgiou
- Sleep, Chronobiology & Addiction Group, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH Surrey, UK
| | - Athanasios Metaxas
- Sleep, Chronobiology & Addiction Group, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH Surrey, UK
| | - Ian Kitchen
- Sleep, Chronobiology & Addiction Group, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH Surrey, UK
| | - Raphaelle Winsky-Sommerer
- Sleep, Chronobiology & Addiction Group, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH Surrey, UK
| | - Alexis Bailey
- Sleep, Chronobiology & Addiction Group, School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH Surrey, UK.
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Peripherally administered oxytocin modulates latent inhibition in a manner consistent with antipsychotic drugs. Behav Brain Res 2014; 278:424-8. [PMID: 25447298 DOI: 10.1016/j.bbr.2014.10.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 10/14/2014] [Accepted: 10/21/2014] [Indexed: 12/26/2022]
Abstract
BACKGROUND Peripherally administered oxytocin (OT) has produced antipsychotic drug (APD)-like effects in animal tests that are predictive of APD efficacy. However, these effects have mainly been demonstrated using animal models of schizophrenia-like deficits in prepulse inhibition (PPI) of the startle reflex. Another schizophrenia-relevant abnormality that is the basis of a predictive animal test for APD efficacy is deficient latent inhibition (LI). LI is the normal suppression of a classically conditioned response when the subject is pre-exposed to the conditioned stimulus (CS) before it is paired with the unconditioned stimulus (UCS). Conditioned taste aversion (CTA), the normal avoidance of ingesting a food or liquid by animals when its taste is associated with an aversive experience, was used to test whether OT facilitates LI consistent with APDs. METHODS Brown Norway rats, known to naturally display attenuated LI, were aversively conditioned on two consecutive exposures to flavored drinking water (0.1% saccharin) by pairing it with malaise-inducing lithium chloride injections. Concurrent with conditioning, rats received subcutaneous OT (0.02, 0.1, 0.5mg/kg) or saline. Some rats were pre-exposed to the flavored water prior to its aversive conditioning (pre-exposed) while others were not (non pre-exposed). Two days after aversive conditioning the amount of flavored water consumed during a 20-min session was recorded. RESULTS As expected, LI, defined as greater consumption by pre-exposed vs. non pre-exposed rats was only weakly exhibited in Brown Norway rats and OT enhanced LI by reducing CTA in pre-exposed rats in a dose-dependent manner, with the 0.02 mg/kg dose producing the strongest effect. CONCLUSIONS The facilitation of LI by OT is consistent with the effects produced by APDs and provides further support for the notion that OT has therapeutic potential for schizophrenia.
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Yuen KW, Garner JP, Carson DS, Keller J, Lembke A, Hyde SA, Kenna HA, Tennakoon L, Schatzberg AF, Parker KJ. Plasma oxytocin concentrations are lower in depressed vs. healthy control women and are independent of cortisol. J Psychiatr Res 2014; 51:30-6. [PMID: 24405552 PMCID: PMC6714974 DOI: 10.1016/j.jpsychires.2013.12.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 12/05/2013] [Accepted: 12/17/2013] [Indexed: 01/01/2023]
Abstract
The neuropeptide oxytocin (OT) promotes social behavior and attenuates stress responsivity in mammals. Recent clinical evidence suggests OT concentrations may be dysregulated in major depression. This study extends previous research by testing whether: 1) OT concentrations vary systematically in depressive disorders with and without hypercortisolemia, 2) gender differences in OT concentrations are observed in depressed vs. healthy control participants, and 3) OT concentrations are predictive of clinical phenotypes. Plasma OT concentrations of psychotic major depressive (PMD; n = 14: 10 female, 4 male), non-psychotic major depressive (NPMD; n = 17: 12 female, 5 male), and non-depressed, healthy control (n = 19: 11 female, 8 male) participants were assayed at 2000, 2400, 0400, and 0800 h. Plasma cortisol concentrations were quantified at 2300 h, and clinical phenotypes were determined. As expected, PMD participants, compared to NPMD and healthy control participants, showed higher plasma cortisol concentrations. Although both depressed groups showed similar OT concentrations, a significant interaction effect between group and gender was observed. Specifically, depressed females exhibited lower mean OT concentrations than depressed males. Further, depressed vs. healthy control female participants exhibited lower mean OT concentrations, whereas depressed vs. healthy control male participants showed a trend in the opposite direction. OT concentrations were also predictive of desirability, drug dependence, and compulsivity scores as measured by the Million Clinical Multiaxial Inventory-III. All findings were independent of cortisol. These data suggest that OT signaling may provide a mechanism by which to better understand female-biased risk to develop depressive disorders and that plasma OT concentrations may be a useful biomarker of certain clinical phenotypes.
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Affiliation(s)
- Kaeli W. Yuen
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 1201 Welch Rd. MSLS Room P104, Stanford, CA 94305-5485, USA
| | - Joseph P. Garner
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 1201 Welch Rd. MSLS Room P104, Stanford, CA 94305-5485, USA,Department of Comparative Medicine, School of Medicine, Stanford University, 287 Campus Dr., Stanford, CA 94305-5410, USA
| | - Dean S. Carson
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 1201 Welch Rd. MSLS Room P104, Stanford, CA 94305-5485, USA
| | - Jennifer Keller
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 401 Quarry Rd., Stanford, CA 94305-5719, USA
| | - Anna Lembke
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 1201 Welch Rd. MSLS Room P104, Stanford, CA 94305-5485, USA
| | - Shellie A. Hyde
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 1201 Welch Rd. MSLS Room P104, Stanford, CA 94305-5485, USA
| | - Heather A. Kenna
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 401 Quarry Rd., Stanford, CA 94305-5719, USA
| | - Lakshika Tennakoon
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 401 Quarry Rd., Stanford, CA 94305-5719, USA
| | - Alan F. Schatzberg
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 401 Quarry Rd., Stanford, CA 94305-5719, USA
| | - Karen J. Parker
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Stanford University, 1201 Welch Rd. MSLS Room P104, Stanford, CA 94305-5485, USA,Corresponding author. Tel.: +1 650 736 9863; fax: +1 (650) 498 7761. (K.J. Parker)
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17
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Wang J, Tai F, Lai X. Cocaine withdrawal influences paternal behavior and associated central expression of vasopressin, oxytocin and tyrosine hydroxylase in mandarin voles. Neuropeptides 2014; 48:29-35. [PMID: 24238615 DOI: 10.1016/j.npep.2013.10.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Revised: 10/02/2013] [Accepted: 10/20/2013] [Indexed: 11/24/2022]
Abstract
Although the disruptive effects of cocaine on the maternal care are well known, little is known about paternal care in the context of cocaine abuse. Vasopressin (AVP), oxytocin (OT) and dopamine (DA) have been found to regulate paternal behavior and are also involved in cocaine abuse. Mandarin voles (Microtus mandarinus) are socially monogamous and display high levels of paternal care. Here, we investigated whether paternal behavior and associated central levels of AVP, OT and DA were altered following 24 h of withdrawal from 4 day administration of 20 mg/kg/day cocaine. Our data shows that vole fathers did not experience altered levels of locomotion during an open field test. However, compared to controls, cocaine attenuated licking/grooming and contact behavior and shortened the latency to crouching, contact and pup retrieval. Last, fewer AVP and OT immunoreactive neurons in the paraventricular nucleus and more tyrosine hydroxylase immunoreactive neurons in the ventral tegmental area were observed in cocaine-treated fathers. These results indicate that cocaine withdrawal disturbs the expression of partial paternal behavior by altering central levels of AVP, OT and DA.
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Affiliation(s)
- Jianli Wang
- College of Biology Sciences and Engineering, Beifang University of Nationalities, Yinchuan, Ningxia 750021, China.
| | - Fadao Tai
- College of Life Sciences, Shaanxi Normal University, Xian, Shaanxi 710062, China
| | - Xiangjun Lai
- College of Biology Sciences and Engineering, Beifang University of Nationalities, Yinchuan, Ningxia 750021, China; College of Life Sciences, Shaanxi Normal University, Xian, Shaanxi 710062, China
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18
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Greydanus DE, Hawver EK, Greydanus MM, Merrick J. Marijuana: current concepts(†). Front Public Health 2013; 1:42. [PMID: 24350211 PMCID: PMC3859982 DOI: 10.3389/fpubh.2013.00042] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 09/23/2013] [Indexed: 12/12/2022] Open
Abstract
Marijuana (cannabis) remains a controversial drug in the twenty-first century. This paper considers current research on use of Cannabis sativa and its constituents such as the cannabinoids. Topics reviewed include prevalence of cannabis (pot) use, other drugs consumed with pot, the endocannabinoid system, use of medicinal marijuana, medical adverse effects of cannabis, and psychiatric adverse effects of cannabis use. Treatment of cannabis withdrawal and dependence is difficult and remains mainly based on psychological therapy; current research on pharmacologic management of problems related to cannabis consumption is also considered. The potential role of specific cannabinoids for medical benefit will be revealed as the twenty-first century matures. However, potential dangerous adverse effects from smoking marijuana are well known and should be clearly taught to a public that is often confused by a media-driven, though false message and promise of benign pot consumption.
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Affiliation(s)
- Donald E Greydanus
- Department of Pediatric and Adolescent Medicine, Western Michigan University School of Medicine , Kalamazoo, MI , USA
| | - Elizabeth K Hawver
- Department of Pediatric and Adolescent Medicine, Western Michigan University School of Medicine , Kalamazoo, MI , USA
| | - Megan M Greydanus
- Department of Pediatric and Adolescent Medicine, Western Michigan University School of Medicine , Kalamazoo, MI , USA
| | - Joav Merrick
- National Institute of Child Health and Human Development , Jerusalem , Israel ; Health Services, Division for Intellectual and Developmental Disabilities, Ministry of Social Affairs and Social Services , Jerusalem , Israel ; Division of Pediatrics, Hadassah Hebrew University Medical Center, Mt. Scopus Campus , Jerusalem , Israel ; Kentucky Children's Hospital, University of Kentucky College of Medicine , Lexington, KY , USA
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19
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Buisman-Pijlman FTA, Sumracki NM, Gordon JJ, Hull PR, Carter CS, Tops M. Individual differences underlying susceptibility to addiction: Role for the endogenous oxytocin system. Pharmacol Biochem Behav 2013; 119:22-38. [PMID: 24056025 DOI: 10.1016/j.pbb.2013.09.005] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 08/12/2013] [Accepted: 09/10/2013] [Indexed: 11/29/2022]
Abstract
Recent research shows that the effects of oxytocin are more diverse than initially thought and that in some cases oxytocin can directly influence the response to drugs and alcohol. Large individual differences in basal oxytocin levels and reactivity of the oxytocin system exist. This paper will review the literature to explore how individual differences in the oxytocin system arise and examine the hypothesis that this may mediate some of the individual differences in susceptibility to addiction and relapse. Differences in the oxytocin system can be based on individual factors, e.g. genetic variation especially in the oxytocin receptor, age or gender, or be the result of early environmental influences such as social experiences, stress or trauma. The paper addresses the factors that cause individual differences in the oxytocin system and the environmental factors that have been identified to induce long-term changes in the developing oxytocin system during different life phases. Individual differences in the oxytocin system can influence effects of drugs and alcohol directly or indirectly. The oxytocin system has bidirectional interactions with the stress-axis, autonomic nervous system, neurotransmitter systems (e.g. dopamine, serotonin and GABA/glutamate) and the immune system. These systems are all important, even vital, in different phases of addiction. It is suggested that early life adversity can change the development of the oxytocin system and the way it modulates other systems. This in turn could minimise the negative feedback loops that would normally exist. Individuals may show only minor differences in behaviour and function unless subsequent stressors or drug use challenges the system. It is postulated that at that time individual differences in oxytocin levels, reactivity of the system or interactions with other systems can influence general resilience, drug effects and the susceptibility to develop problematic drug and alcohol use.
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Affiliation(s)
| | - Nicole M Sumracki
- Discipline of Pharmacology, The University of Adelaide, Adelaide, SA 5005, Australia.
| | - Jake J Gordon
- Discipline of Pharmacology, The University of Adelaide, Adelaide, SA 5005, Australia.
| | - Philip R Hull
- Discipline of Pharmacology, The University of Adelaide, Adelaide, SA 5005, Australia.
| | - C Sue Carter
- Department of Psychiatry, University of North Carolina, Chapel Hill 27599, USA.
| | - Mattie Tops
- Department of Clinical Psychology, VU University Amsterdam, van der Boechorststraat 1, NL-1081 BT Amsterdam, The Netherlands.
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20
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Williams SK, Johns JM. Prenatal and gestational cocaine exposure: Effects on the oxytocin system and social behavior with implications for addiction. Pharmacol Biochem Behav 2013; 119:10-21. [PMID: 23880214 DOI: 10.1016/j.pbb.2013.07.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 07/02/2013] [Accepted: 07/08/2013] [Indexed: 12/01/2022]
Abstract
Drug abuse during pregnancy is a major public health concern, with negative consequences throughout development. Prenatal cocaine exposure (PCE) in rats produces social behavior deficits with corresponding changes in neuroendocrine and monoaminergic signaling. The relevance of parental care in social behavior maturity cannot be ignored, and gestational exposure to cocaine severely disrupts parental care, thus impacting the early environment of the offspring. Oxytocin (Oxt) is critical in regulating social behaviors and central levels are disrupted following acute and chronic cocaine (CC) treatment in postpartum rat dams, coincident with deficits in maternal care. We will discuss studies aimed to determine the relative contribution of PCE and CC-induced deficits in maternal care to social behaviors and Oxt signaling across development. PCE results in decreased social (including parental) behaviors in adolescence and adulthood. PCE is also associated with increased aggression in adults. Rearing by CC-exposed mothers synergistically increases the behavioral effects of PCE. Rearing by CC-exposed mothers, but not PCE, disrupts Oxt levels and mRNA in regions relevant to social behavior, but does not affect receptors in postpartum adult offspring. Preliminary work indicates that PCE/CC rearing has dynamic effects on Oxt levels and receptors in neonatal rat pups, suggesting very early regulation of Oxt signaling. This work highlights how the interactive role of Oxt signaling and behavioral context throughout development can be derailed by drug abuse during pregnancy. The relevance of disrupted Oxt to intergenerational transmission of addiction is briefly discussed.
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Affiliation(s)
- S K Williams
- Section on Neural Gene Expression, National Institute of Mental Health, Bethesda, MD, United States.
| | - J M Johns
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Department of Psychology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States; Curriculum of Neurobiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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21
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Nonsocial functions of hypothalamic oxytocin. ISRN NEUROSCIENCE 2013; 2013:179272. [PMID: 24967304 PMCID: PMC4045544 DOI: 10.1155/2013/179272] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 04/23/2013] [Indexed: 01/06/2023]
Abstract
Oxytocin (OXT) is a hypothalamic neuropeptide composed of nine amino acids. The functions of OXT cover a variety of social and nonsocial activity/behaviors. Therapeutic effects of OXT on aberrant social behaviors are attracting more attention, such as social memory, attachment, sexual behavior, maternal behavior, aggression, pair bonding, and trust. The nonsocial behaviors/functions of brain OXT have also received renewed attention, which covers brain development, reproduction, sex, endocrine, immune regulation, learning and memory, pain perception, energy balance, and almost all the functions of peripheral organ systems. Coordinating with brain OXT, locally produced OXT also involves the central and peripheral actions of OXT. Disorders in OXT secretion and functions can cause a series of aberrant social behaviors, such as depression, autism, and schizophrenia as well as disturbance of nonsocial behaviors/functions, such as anorexia, obesity, lactation failure, osteoporosis, diabetes, and carcinogenesis. As more and more OXT functions are identified, it is essential to provide a general view of OXT functions in order to explore the therapeutic potentials of OXT. In this review, we will focus on roles of hypothalamic OXT on central and peripheral nonsocial functions.
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22
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Zanos P, Wright SR, Georgiou P, Yoo JH, Ledent C, Hourani SM, Kitchen I, Winsky-Sommerer R, Bailey A. Chronic methamphetamine treatment induces oxytocin receptor up-regulation in the amygdala and hypothalamus via an adenosine A2A receptor-independent mechanism. Pharmacol Biochem Behav 2013; 119:72-9. [PMID: 23680573 DOI: 10.1016/j.pbb.2013.05.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 04/30/2013] [Accepted: 05/03/2013] [Indexed: 12/12/2022]
Abstract
There is mounting evidence that the neuropeptide oxytocin is a possible candidate for the treatment of drug addiction. Oxytocin was shown to reduce methamphetamine self-administration, conditioned place-preference, hyperactivity and reinstatement in rodents, highlighting its potential for the management of methamphetamine addiction. Thus, we hypothesised that the central endogenous oxytocinergic system is dysregulated following chronic methamphetamine administration. We tested this hypothesis by examining the effect of chronic methamphetamine administration on oxytocin receptor density in mice brains with the use of quantitative receptor autoradiographic binding. Saline (4ml/kg/day, i.p.) or methamphetamine (1mg/kg/day, i.p.) was administered daily for 10 days to male, CD1 mice. Quantitative autoradiographic mapping of oxytocin receptors was carried out with the use of [(125)I]-vasotocin in brain sections of these animals. Chronic methamphetamine administration induced a region specific upregulation of oxytocin receptor density in the amygdala and hypothalamus, but not in the nucleus accumbens and caudate putamen. As there is evidence suggesting an involvement of central adenosine A2A receptors on central endogenous oxytocinergic function, we investigated whether these methamphetamine-induced oxytocinergic neuroadaptations are mediated via an A2A receptor-dependent mechanism. To test this hypothesis, autoradiographic oxytocin receptor binding was carried out in brain sections of male CD1 mice lacking A2A receptors which were chronically treated with methamphetamine (1mg/kg/day, i.p. for 10 days) or saline. Similar to wild-type animals, chronic methamphetamine administration induced a region-specific upregulation of oxytocin receptor binding in the amygdala and hypothalamus of A2A receptor knockout mice and no genotype effect was observed. These results indicate that chronic methamphetamine use can induce profound neuroadaptations of the oxytocinergic receptor system in brain regions associated with stress, emotionality and social bonding and that these neuroadaptations are independent on the presence of A2A receptors. These results may at least partly explain some of the behavioural consequences of chronic methamphetamine use.
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Affiliation(s)
- Panos Zanos
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK
| | - Sherie R Wright
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK
| | - Polymnia Georgiou
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK
| | - Ji Hoon Yoo
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK
| | - Catherine Ledent
- Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire, Université Libre de Bruxelles, B-1070, Belgium
| | - Susanna M Hourani
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK
| | - Ian Kitchen
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK
| | - Raphaelle Winsky-Sommerer
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK
| | - Alexis Bailey
- Sleep, Chronobiology & Addiction Group, Department of Biochemistry & Physiology, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, Surrey, UK.
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Rehme M, Hillemacher T, Heberlein A. Comment on “Intranasal Oxytocin Blocks Alcohol Withdrawal in Human Subjects” by Pedersen and Colleagues (). Alcohol Clin Exp Res 2013; 37:720-1. [DOI: 10.1111/acer.12147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 02/18/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Marie Rehme
- Center for Addiction Research (CARe) (MR, TH, AH); Department of Psychiatry, Social Psychiatry; Hannover Medical School; Hannover; Germany
| | - Thomas Hillemacher
- Center for Addiction Research (CARe) (MR, TH, AH); Department of Psychiatry, Social Psychiatry; Hannover Medical School; Hannover; Germany
| | - Annemarie Heberlein
- Center for Addiction Research (CARe) (MR, TH, AH); Department of Psychiatry, Social Psychiatry; Hannover Medical School; Hannover; Germany
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24
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Carson DS, Guastella AJ, Taylor ER, McGregor IS. A brief history of oxytocin and its role in modulating psychostimulant effects. J Psychopharmacol 2013; 27:231-47. [PMID: 23348754 DOI: 10.1177/0269881112473788] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Over the past century, the polypeptide oxytocin has played an important role in medicine with major highlights including the identification of its involvement in parturition and the milk let-down reflex. Oxytocin is now implicated in an extensive range of psychological phenomena including reward and memory processes and has been investigated as a treatment for several psychiatric disorders including addiction, anxiety, autism, and schizophrenia. In this review, we first provide an historical overview of oxytocin and describe key aspects of its physiological activity. We then outline some pharmacological limitations in this field of research before highlighting the role of oxytocin in a wide range of behavioral and neuronal processes. Finally, we review evidence for a modulatory role of oxytocin with regard to psychostimulant effects. Key findings suggest that oxytocin attenuates a broad number of cocaine and methamphetamine induced behaviors and associated neuronal activity in rodents. Evidence also outlines a role for oxytocin in the prosocial effects of 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy) in both rodents and humans. Clinical trials should now investigate the effectiveness of oxytocin as a novel intervention for psychostimulant addiction and should aim to determine its specific role in the therapeutic properties of MDMA that are currently being investigated.
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Affiliation(s)
- Dean S Carson
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 1201 Welch Rd, MSLS, Mail Code 5485, Stanford, CA 94305, USA.
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Paternal deprivation alters play-fighting, serum corticosterone and the expression of hypothalamic vasopressin and oxytocin in juvenile male mandarin voles. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2012; 198:787-96. [DOI: 10.1007/s00359-012-0748-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 08/07/2012] [Accepted: 08/07/2012] [Indexed: 01/25/2023]
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Qi J, Han WY, Yang JY, Wang LH, Dong YX, Wang F, Song M, Wu CF. Oxytocin regulates changes of extracellular glutamate and GABA levels induced by methamphetamine in the mouse brain. Addict Biol 2012; 17:758-69. [PMID: 22507692 DOI: 10.1111/j.1369-1600.2012.00439.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Oxytocin (OT), a neurohypophyseal neuropeptide, affects adaptive processes of the central nervous system. In the present study, we investigated the effects of OT on extracellular levels of glutamate (Glu) and γ-aminobutyric acid (GABA) induced by methamphetamine (MAP) in the medial prefrontal cortex (mPFC) and dorsal hippocampus (DHC) of freely moving mice, using in vivo microdialysis coupled to high-performance liquid chromatography and fluorescence detection. The results showed that OT had no effect on basal Glu levels, but attenuated MAP-induced Glu increase in the mPFC and decrease in the DHC. OT increased the basal levels of extracellular GABA in mPFC and DHC of mice, and inhibited the MAP-induced GABA decrease in DHC. Western blot results indicated that OT significantly inhibited the increased glutamatergic receptor (NR1 subunit) levels in the PFC after acute MAP administration, whereas OT further enhanced the elevated levels of glutamatergic transporter (GLT1) induced by MAP in the hippocampus of mice. Atosiban, a selective inhibitor of OT receptor, antagonized the effects of OT. The results provided the first neurochemical evidence that OT, which exerted its action via its receptor, decreased Glu release induced by MAP, and attenuated the changes in glutamatergic neurotransmission partially via regulation of NR1 and GLT1 expression. OT-induced extracellular GABA increase also suggests that OT acts potentially as an inhibitory neuromodulator in mPFC and DHC of mice.
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Affiliation(s)
- Jia Qi
- Department of Pharmacology, Shenyang Pharmaceutical University, China
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Dere E, Pause BM, Pietrowsky R. Emotion and episodic memory in neuropsychiatric disorders. Behav Brain Res 2010; 215:162-71. [DOI: 10.1016/j.bbr.2010.03.017] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Accepted: 03/05/2010] [Indexed: 11/25/2022]
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Dopamine and oxytocin interactions underlying behaviors: potential contributions to behavioral disorders. CNS Neurosci Ther 2010; 16:e92-123. [PMID: 20557568 DOI: 10.1111/j.1755-5949.2010.00154.x] [Citation(s) in RCA: 233] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Dopamine is an important neuromodulator that exerts widespread effects on the central nervous system (CNS) function. Disruption in dopaminergic neurotransmission can have profound effects on mood and behavior and as such is known to be implicated in various neuropsychiatric behavioral disorders including autism and depression. The subsequent effects on other neurocircuitries due to dysregulated dopamine function have yet to be fully explored. Due to the marked social deficits observed in psychiatric patients, the neuropeptide, oxytocin is emerging as one particular neural substrate that may be influenced by the altered dopamine levels subserving neuropathologic-related behavioral diseases. Oxytocin has a substantial role in social attachment, affiliation and sexual behavior. More recently, it has emerged that disturbances in peripheral and central oxytocin levels have been detected in some patients with dopamine-dependent disorders. Thus, oxytocin is proposed to be a key neural substrate that interacts with central dopamine systems. In addition to psychosocial improvement, oxytocin has recently been implicated in mediating mesolimbic dopamine pathways during drug addiction and withdrawal. This bi-directional role of dopamine has also been implicated during some components of sexual behavior. This review will discuss evidence for the existence dopamine/oxytocin positive interaction in social behavioral paradigms and associated disorders such as sexual dysfunction, autism, addiction, anorexia/bulimia, and depression. Preliminary findings suggest that whilst further rigorous testing has to be conducted to establish a dopamine/oxytocin link in human disorders, animal models seem to indicate the existence of broad and integrated brain circuits where dopamine and oxytocin interactions at least in part mediate socio-affiliative behaviors. A profound disruption to these pathways is likely to underpin associated behavioral disorders. Central oxytocin pathways may serve as a potential therapeutic target to improve mood and socio-affiliative behaviors in patients with profound social deficits and/or drug addiction.
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Yang JY, Qi J, Han WY, Wang F, Wu CF. Inhibitory role of oxytocin in psychostimulant-induced psychological dependence and its effects on dopaminergic and glutaminergic transmission. Acta Pharmacol Sin 2010; 31:1071-4. [PMID: 20729875 DOI: 10.1038/aps.2010.140] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Psychostimulants are frequently abused as a result of their stimulatory effects on several neurotransmitter systems within the central nervous system. Both dopaminergic and glutaminergic neurotransmissions have been closely associated with psychostimulant dependence. In addition to its classical endocrine function in the periphery, oxytocin, an important neurohypophyseal neuropeptide in the central nervous system, has a wide range of behavioral effects, including regulating drug abuse. The present paper reviews the progress of research into the role of oxytocin in reducing psychostimulant-induced psychological dependence and the mechanisms by which oxytocin mediates its effects.
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The role of mesocorticolimbic dopamine in regulating interactions between drugs of abuse and social behavior. Neurosci Biobehav Rev 2010; 35:498-515. [PMID: 20600286 DOI: 10.1016/j.neubiorev.2010.06.004] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 06/08/2010] [Accepted: 06/11/2010] [Indexed: 01/07/2023]
Abstract
The use of addictive drugs can have profound short- and long-term consequences on social behaviors. Similarly, social experiences and the presence or absence of social attachments during early development and throughout life can greatly influence drug intake and the susceptibility to drug abuse. The following review details this reciprocal interaction, focusing on common drugs of abuse (e.g., psychostimulants, opiates, alcohol and nicotine) and social behaviors (e.g., maternal, sexual, play, aggressive and bonding behaviors). The neural mechanisms underlying this interaction are discussed, with a particular emphasis on the involvement of the mesocorticolimbic dopamine system.
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Shahrokh DK, Zhang TY, Diorio J, Gratton A, Meaney MJ. Oxytocin-dopamine interactions mediate variations in maternal behavior in the rat. Endocrinology 2010; 151:2276-86. [PMID: 20228171 PMCID: PMC2869254 DOI: 10.1210/en.2009-1271] [Citation(s) in RCA: 265] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Variations in maternal behavior among lactating rats associate with differences in estrogen-oxytocin interactions in the medial preoptic area (mPOA) and in dopamine levels in the nucleus accumbens (nAcc). Thus, stable, individual differences in pup licking/grooming (LG) are abolished by oxytocin receptor blockade or treatments that eliminate differences in the nAcc dopamine signal. We provide novel evidence for a direct effect of oxytocin at the level of the ventral tegmental area (VTA) in the regulation of nAcc dopamine levels. Mothers that exhibit consistently increased pup LG (i.e. high LG mothers) by comparison with low LG mothers show increased oxytocin expression in the mPOA and the paraventricular nucleus of the hypothalamus and increased projections of oxytocin-positive cells from both mPOA and paraventricular nucleus of the hypothalamus to the VTA. Direct infusion of oxytocin into the VTA increased the dopamine signal in the nAcc. Finally, high compared with low LG mothers show greater increases in dopamine signal in the nAcc during bouts of pup LG, and this difference is abolished with infusions of an oxytocin receptor antagonist directly into the VTA. These studies reveal a direct effect of oxytocin on dopamine release within the mesocorticolimbic dopamine system and are consistent with previous reports of oxytocin-dopamine interactions in the establishment and maintenance of social bonds.
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Affiliation(s)
- Dara K Shahrokh
- Sackler Program for Epigenetics and Psychobiology at McGill University, Douglas Mental Health University Institute, McGill University, Montréal, Canada
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Anacker AMJ, Ryabinin AE. Biological contribution to social influences on alcohol drinking: evidence from animal models. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2010; 7:473-93. [PMID: 20616986 PMCID: PMC2872279 DOI: 10.3390/ijerph7020473] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Accepted: 02/08/2010] [Indexed: 11/27/2022]
Abstract
Social factors have a tremendous influence on instances of heavy drinking and in turn impact public health. However, it is extremely difficult to assess whether this influence is only a cultural phenomenon or has biological underpinnings. Research in non-human primates demonstrates that the way individuals are brought up during early development affects their future predisposition for heavy drinking, and research in rats demonstrates that social isolation, crowding or low social ranking can lead to increased alcohol intake, while social defeat can decrease drinking. Neurotransmitter mechanisms contributing to these effects (i.e., serotonin, GABA, dopamine) have begun to be elucidated. However, these studies do not exclude the possibility that social effects on drinking occur through generalized stress responses to negative social environments. Alcohol intake can also be elevated in positive social situations, for example, in rats following an interaction with an intoxicated peer. Recent studies have also begun to adapt a new rodent species, the prairie vole, to study the role of social environment in alcohol drinking. Prairie voles demonstrate a high degree of social affiliation between individuals, and many of the neurochemical mechanisms involved in regulation of these social behaviors (for example, dopamine, central vasopressin and the corticotropin releasing factor system) are also known to be involved in regulation of alcohol intake. Naltrexone, an opioid receptor antagonist approved as a pharmacotherapy for alcoholic patients, has recently been shown to decrease both partner preference and alcohol preference in voles. These findings strongly suggest that mechanisms by which social factors influence drinking have biological roots, and can be studied using rapidly developing new animal models.
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Affiliation(s)
- Allison M J Anacker
- Department of Behavioral Neuroscience, Oregon Health & Science University, 3181 SW Sam Jackson Pk Rd L470, Portland, OR 97239, USA.
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Williams SK, Cox ET, McMurray MS, Fay EE, Jarrett TM, Walker CH, Overstreet DH, Johns JM. Simultaneous prenatal ethanol and nicotine exposure affect ethanol consumption, ethanol preference and oxytocin receptor binding in adolescent and adult rats. Neurotoxicol Teratol 2009; 31:291-302. [PMID: 19539752 PMCID: PMC2743885 DOI: 10.1016/j.ntt.2009.06.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 05/21/2009] [Accepted: 06/09/2009] [Indexed: 11/20/2022]
Abstract
Ethanol consumption and smoking during pregnancy are common, despite the known adverse effects on the fetus. The teratogenicity of each drug independently is well established; however, the effects of concurrent exposure to ethanol and nicotine in preclinical models remain unclear. This study examined the impact of simultaneous prenatal exposure to both ethanol and nicotine on offspring ethanol preference behaviors and oxytocin system dynamics. Rat dams were given liquid diet (17% ethanol derived calories (EDC)) on gestational day (GD) 5 and 35% EDC from GD 6-20 and concurrently an osmotic minipump delivered nicotine (3-6mg/kg/day) from GD 4-postpartum day 10. Offspring were tested for ethanol preference during adolescence (postnatal day (PND) 30-43) and again at adulthood (PND 60-73), followed by assays for oxytocin mRNA expression and receptor binding in relevant brain regions. Prenatal exposure decreased ethanol preference in males during adolescence, and decreased consumption and preference in females during adulthood compared to controls. Oxytocin receptor binding in the nucleus accumbens and hippocampus was increased in adult prenatally exposed males only. Prenatal exposure to these drugs sex-specifically decreased ethanol preference behavior in offspring unlike reports for either drug separately. The possible role of oxytocin in reduction of ethanol consumption behavior is highlighted.
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Affiliation(s)
- Sarah K Williams
- Curriculum in Neurobiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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34
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Roth-Deri I, Green-Sadan T, Yadid G. Beta-endorphin and drug-induced reward and reinforcement. Prog Neurobiol 2008; 86:1-21. [PMID: 18602444 DOI: 10.1016/j.pneurobio.2008.06.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Accepted: 06/11/2008] [Indexed: 01/13/2023]
Abstract
Although drugs of abuse have different acute mechanisms of action, their brain pathways of reward exhibit common functional effects upon both acute and chronic administration. Long known for its analgesic effect, the opioid beta-endorphin is now shown to induce euphoria, and to have rewarding and reinforcing properties. In this review, we will summarize the present neurobiological and behavioral evidences that support involvement of beta-endorphin in drug-induced reward and reinforcement. Currently, evidence supports a prominent role for beta-endorphin in the reward pathways of cocaine and alcohol. The existing information indicating the importance of beta-endorphin neurotransmission in mediating the reward pathways of nicotine and THC, is thus far circumstantial. The studies described herein employed diverse techniques, such as biochemical measurements of beta-endorphin in various brain sites and plasma, and behavioral measurements, conducted following elimination (via administration of anti-beta-endorphin antibodies or using mutant mice) or augmentation (by intracerebral administration) of beta-endorphin. We suggest that the reward pathways for different addictive drugs converge to a common pathway in which beta-endorphin is a modulating element. Beta-endorphin is involved also with distress. However, reviewing the data collected so far implies a discrete role, beyond that of a stress response, for beta-endorphin in mediating the substance of abuse reward pathway. This may occur via interacting with the mesolimbic dopaminergic system and also by its interesting effects on learning and memory. The functional meaning of beta-endorphin in the process of drug-seeking behavior is discussed.
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Affiliation(s)
- Ilana Roth-Deri
- Neuropharmacology Section, The Mina and Everard Goodman Faculty of Life Sciences and The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel
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35
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López Patiño MA, Yu L, Yamamoto BK, Zhdanova IV. Gender differences in zebrafish responses to cocaine withdrawal. Physiol Behav 2008; 95:36-47. [PMID: 18499199 DOI: 10.1016/j.physbeh.2008.03.021] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Revised: 03/26/2008] [Accepted: 03/26/2008] [Indexed: 11/24/2022]
Abstract
The acute responses to cocaine and its withdrawal contribute to cocaine dependence and potentiate relapse, with gender being one of the genetic factors affecting the outcome. Here we report that in both male and female zebrafish (Danio rerio, AB strain), an initial low-dose cocaine treatment (1.5 muM, immersion) does not acutely change their behavior. The cocaine withdrawal, however, is associated with an anxiety-like state that develops earlier in female zebrafish but is more robust and persistent in males, and can be acutely attenuated by cocaine administration. This is not a result of gender differences in the expression of anxiety-like state, since behavioral responses to an anxiogenic drug, FG-7142, are similar in male and female zebrafish. The basal brain dopamine (DA) levels and the expression of dopamine transporter mRNA (zDAT) show no significant sexual dimorphism. Acute cocaine exposure does not significantly change DA or zDAT. Withdrawal from repeated cocaine administration results in an overall reduction in zDAT, as well as an increase in DA levels. Neither treatment leads to significant gender differences in brain DA or zDAT. The common and gender-specific effects of cocaine on zebrafish, a well-characterized model of vertebrate development and genetics, should help in understanding the mechanisms involved in the anxiety associated with cocaine withdrawal and provide new opportunities in search for therapeutic solutions.
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Affiliation(s)
- Marcos A López Patiño
- Department of Anatomy and Neurobiology, Boston University School of Medicine, 715 Albany St. R-913 Boston, MA 02118, USA
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36
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Qi J, Yang JY, Song M, Li Y, Wang F, Wu CF. Inhibition by oxytocin of methamphetamine-induced hyperactivity related to dopamine turnover in the mesolimbic region in mice. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2007; 376:441-8. [PMID: 18092152 DOI: 10.1007/s00210-007-0245-8] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Accepted: 12/05/2007] [Indexed: 10/22/2022]
Abstract
Accumulated data have shown the neuroactive properties of oxytocin (OT), a neurohypophyseal neuropeptide, and its capability of reducing the abuse potential of drugs. The present study investigated the effect of OT on methamphetamine (MAP)-induced hyperactivity in mice and its possible mechanism of action. Locomotor activity was measured after administered with MAP using an infrared sensor. High-performance liquid chromatography with electrochemical detection (HPLC-ECD) was used to detect the content of monoamines and their metabolites in the striatum and accumbens and prefrontal cortex in mice after the behavioral test. OT (0.1, 0.5, and 2.5 microg/mouse, i.c.v.) had no effect on locomotor activity in naïve mice, but inhibited, in a dose-dependent manner, the hyperactivity induced by acute administration of MAP. Atosiban (Ato) (2.0 microg/mouse, i.c.v.), the selective inhibitor of OT receptor, attenuated the inhibitory effect of OT on MAP. A marked reduction of the ratios of 3, 4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) to dopamine (DA) was observed in the striatum and accumbens of mice after acute administration of MAP. OT (2.5 microg, i.c.v.) significantly inhibited the reduction of DOPAC/DA and HVA/DA ratios. However, Ato decreased the ratio of DOPAC/DA significantly in mice compared with OT (2.5 microg) in combination with MAP. There was no significant change in serotonin (5-HT) metabolism in mice after a single administration of MAP. These results suggested that OT inhibited the MAP-induced hyperactivity by altering the DA turnover in the mesolimbic region of mice.
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Affiliation(s)
- Jia Qi
- Department of Pharmacology, Shenyang Pharmaceutical University, 110016, Shenyang, People's Republic of China
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37
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López-Patiño MA, Yu L, Cabral H, Zhdanova IV. Anxiogenic effects of cocaine withdrawal in zebrafish. Physiol Behav 2007; 93:160-71. [PMID: 17889042 DOI: 10.1016/j.physbeh.2007.08.013] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2007] [Revised: 06/30/2007] [Accepted: 08/20/2007] [Indexed: 11/19/2022]
Abstract
Continued usage of cocaine is determined by genetic, conditioned and homeostatic factors, while it is reinforced by drug-induced reward and the emotionally negative state of drug withdrawal, which includes anxiety. The molecular mechanisms of these long-term behavioral and physiological alterations have yet to be fully elucidated. Here we demonstrate that in zebrafish, a wide range of non-anesthetic cocaine doses, 0.015-15 muM, does not result in acute alterations in locomotor activity, in spite of the high brain cocaine levels induced (7-120 pg/microg protein). Conversely, cocaine withdrawal causes hyperactivity associated with stereotypy. The behavioral hyperactivity is progressively increased during the initial period of withdrawal (24-72 h) and is maintained for at least 5 days. Such effect of cocaine withdrawal is aggravated by environmental stimulation and attenuated in the home environment. Administration of cocaine (1.5 microM) or a non-sedative dose of diazepam (5 microM, immersion) acutely counteracts withdrawal-associated hyperactivity and stereotypy in zebrafish, with the magnitude of these effects positively correlating with the degree of prior increase in basal activity. Administration of an anxiogenic benzodiazepine inverse agonist, FG-7142, results in zebrafish behavior similar to that observed during cocaine withdrawal. Together, the results suggest that cocaine withdrawal produces long-lasting behavioral effects in zebrafish which are consistent with an anxiety-like state. Thus, zebrafish, a powerful model for the study of vertebrate genetics, could provide insights into the molecular mechanisms of drug withdrawal.
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Affiliation(s)
- Marcos A López-Patiño
- Department of Anatomy and Neurobiology, School of Medicine, Boston University, 715 Albany Street, Boston, MA 02118, USA
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Szyf M, Weaver ICG, Champagne FA, Diorio J, Meaney MJ. Maternal programming of steroid receptor expression and phenotype through DNA methylation in the rat. Front Neuroendocrinol 2005; 26:139-62. [PMID: 16303171 DOI: 10.1016/j.yfrne.2005.10.002] [Citation(s) in RCA: 236] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 10/19/2005] [Accepted: 10/19/2005] [Indexed: 12/26/2022]
Abstract
Increased levels of pup licking/grooming and arched-back nursing by rat mothers over the first week of life alter the epigenome at a glucocorticoid receptor gene promoter in the hippocampus of the offspring. Differences in the DNA methylation pattern between the offspring of High and Low licking/grooming--arched-back mothers emerge over the first week of life, are reversed with cross-fostering, persist into adulthood and are associated with altered histone acetylation and transcription factor (NGFI-A) binding to the glucocorticoid receptor promoter. Central infusion of the adult offspring with the histone deacetylase inhibitor trichostatin A removes the previously defined epigenomic group differences in histone acetylation, DNA methylation, NGFI-A binding, glucocorticoid receptor expression, and hypothalamic-pituitary-adrenal responses to stress, thus suggesting a causal relation between the epigenomic state, glucocorticoid receptor expression and the effects of maternal care on stress responses in the offspring. These findings demonstrate that an epigenomic state of a gene can be established through a behavioral mode of programming and that in spite of the inherent stability of this epigenomic mark, it is dynamic and potentially reversible.
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Affiliation(s)
- Moshe Szyf
- McGill Program for the Study of Behavior, Genes and Environment, McGill University, Montreal, Canada
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Champagne FA, Chretien P, Stevenson CW, Zhang TY, Gratton A, Meaney MJ. Variations in nucleus accumbens dopamine associated with individual differences in maternal behavior in the rat. J Neurosci 2004; 24:4113-23. [PMID: 15115806 PMCID: PMC6729285 DOI: 10.1523/jneurosci.5322-03.2004] [Citation(s) in RCA: 287] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2003] [Revised: 03/12/2004] [Accepted: 03/12/2004] [Indexed: 11/21/2022] Open
Abstract
Lactating rats exhibit stable individual differences in pup licking/grooming. We used in vivo voltammetry to monitor changes in extracellular dopamine (DA) in the nucleus accumbens (n. Acc) shell of lactating rats interacting with pups and found that (1) the DA signal increased significantly with pup licking/grooming; (2) the onset of such increases preceded pup licking/grooming; and (3) the magnitude and duration of the increase in the DA signal were significantly correlated with the duration of the licking/grooming bout. In females characterized on the basis of behavioral observations as high-licking/grooming mothers, the magnitude of the increase in the DA signal associated with licking/grooming was significantly greater than in low-licking/grooming dams. Dopamine transporter binding in the n. Acc was increased in low-compared with high-licking/grooming mothers. Injection of the selective DA uptake inhibitor GBR 12909 [1-(2-(Bis-(4-fluorophenyl)methoxy)ethyl)-4-(3 phenypropyl)piperazine dihydrochloride] (5 mg/kg, s.c.) increased the DA signal in the n. Acc and pup licking/grooming in low-licking/grooming mothers to levels comparable with those observed in high-licking/grooming dams. Receptor autoradiographic studies showed elevated levels of D1 and D3 receptors in the n. Acc shell region in high-licking/grooming dams. These results suggest that high- and low-licking/grooming dams differ in mesolimbic dopaminergic activity associated with mother-pup interactions. Such differences may serve as neural substrates for individual differences in the motivational component of maternal behavior.
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Affiliation(s)
- Frances A Champagne
- Developmental Neuroendocrinology Laboratory, Douglas Hospital Research Centre, McGill University, Montreal, Quebec H4H 1R3, Canada
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Liu Y, Wang ZX. Nucleus accumbens oxytocin and dopamine interact to regulate pair bond formation in female prairie voles. Neuroscience 2004; 121:537-44. [PMID: 14568015 DOI: 10.1016/s0306-4522(03)00555-4] [Citation(s) in RCA: 340] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Although oxytocin (OT) and dopamine (DA) have been implicated in pair bond formation in monogamous prairie voles (Microtus ochrogaster), the nature of potential interactions between these two neurochemical systems and the brain circuits important for such interactions in the regulation of pair bonding have not been explored. Here, we demonstrated that access to both OT and DA D2-type receptors is necessary for pair bond formation, as blockade of either type of receptor prevented partner preferences induced by OT or a D2-type agonist. We also demonstrated that the nucleus accumbens (NAcc) is a brain area important for such OT-DA interactions. In NAcc, blockade of OT receptors prevented partner preferences induced by a D2-type agonist whereas blockade of D2-type, but not D1-type, DA receptors blocked OT-induced partner preferences. Together, our data suggest that concurrent activation of OT and DA D2-type receptors in NAcc is essential for pair bond formation in female prairie voles.
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Affiliation(s)
- Y Liu
- Department of Psychology and Program in Neuroscience, Florida State University, Tallahassee 32306, USA
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Bujdosó E, Jászberényi M, Farkas J, Tóth G, Wollemann M, Telegdy G. Behavioral and neuroendocrine actions of the Met-enkephalin-related peptide MERF. Horm Behav 2003; 43:302-11. [PMID: 12694640 DOI: 10.1016/s0018-506x(03)00004-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The effects and the mediation of the action of the proenkephalin derivative Met(5)-enkephalin-Arg(6)-Phe(7) (MERF) on the hypothalamo-pituitary-adrenal (HPA) system and open-field behavior were investigated in mice. Intracerebroventricular injection of the heptapeptide increased square crossing, rearing, and plasma corticosterone level. To characterize the receptors involved in these neuroendocrine processes, animals were pretreated either with the nonselective opioid antagonist naloxone or the kappa-antagonist nor-binaltorphimine (nor-BNI). Both antagonists dose-dependently attenuated the HPA activation elicited by MERF. Naloxone also blocked the behavioral responses, but nor-binaltorphimine did not elicit a significant inhibition. The dopamine antagonist haloperidol and a corticotropin-releasing hormone (CRH) antagonist were also preadministered to shed light on the transmission of the actions of MERF. Both the motor responses and the HPA activation were diminished by the preadministration of the CRH antagonist, while haloperidol attenuated only square crossing and rearing. To investigate the direct effect of MERF on the dopaminergic system, dopamine release of striatal slices was measured in a superfusion system. Neither the basal nor the electric impulse-evoked dopamine release was modified by MERF. The results suggest that opioid-mediation predominate in the neuroendocrine actions of MERF, and the effect of the heptapeptide on the HPA system seems to be mediated by kappa-receptors. In the behavioral responses evoked by MERF, both CRH release and the action of the dopaminergic neurons of the subcortical motor system might be involved. MERF also appears to activate the paraventricular CRH neurons, but dopaminergic transmission does not seem to play a significant role in its hypothalamic action.
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Affiliation(s)
- E Bujdosó
- Department of Pathophysiology, University of Szeged, Neurohumoral Research Group, Hungarian Academy of Sciences, Szeged, Hungary
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Abstract
All social relationships are dependent on an organism's ability to remember conspecifics. Social memory may be a unique form of memory, critical for reproduction, territorial defense, and the establishment of dominance hierarchies in a natural context. In the laboratory, social memory can be assessed reliably by measuring the reduction in investigation of a familiar partner relative to novel conspecifics. The neurohypophyseal neuropeptides oxytocin and vasopressin have been shown to influence a number of forms of social behavior, including affiliation, aggression, and reproduction. This article reviews vasopressin and oxytocin effects on social cognition, particularly the acquisition and retention of social recognition in rats and mice. Studies in rats have demonstrated that vasopressin in specific neural pathways, such as the lateral septum, is necessary for social recognition. As vasopressin facilitates recall when given after an initial encounter, the peptide appears important for the consolidation not the acquisition of a social memory. Although oxytocin has complex effects on social memory in rats, mice with a null mutation of the oxytocin gene are completely socially amnestic without other cognitive deficits evident. As oxytocin given centrally before but not after the initial encounter restores social recognition in these mutant mice, the neuropeptide appears critical for the acquisition rather than the consolidation phase of memory. Oxytocin's effects on social memory are mediated via a discrete cell population in the medial amygdala. These findings support the hypothesis that vasopressin and oxytocin are essential for social memory, although they appear to influence different cognitive processes and may modulate different neural systems. (c) Elsevier Science.
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Affiliation(s)
- Jennifer N Ferguson
- Center for Behavioral Neuroscience, Emory University, Atlanta, Georgia 30322, USA
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43
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Prevention of cannabinoid withdrawal syndrome by lithium: involvement of oxytocinergic neuronal activation. J Neurosci 2002. [PMID: 11739594 DOI: 10.1523/jneurosci.21-24-09867.2001] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cannabis (i.e., marijuana and cannabinoids) is the most commonly used illicit drug in developed countries, and the lifetime prevalence of marijuana dependence is the highest of all illicit drugs in the United States. To provide clues for finding effective pharmacological treatment for cannabis-dependent patients, we examined the effects and possible mechanism of lithium administration on the cannabinoid withdrawal syndrome in rats. A systemic injection of the mood stabilizer lithium, at serum levels that were clinically relevant, prevented the cannabinoid withdrawal syndrome. The effects of lithium were accompanied by expression of the cellular activation marker Fos proteins within most oxytocin-immunoreactive neurons and a significant increase in oxytocin mRNA expression in the hypothalamic paraventricular and supraoptic nuclei. Lithium also produced a significant elevation of oxytocin levels in the peripheral blood. We suggest that the effects of lithium against the cannabinoid withdrawal syndrome are mediated by oxytocinergic neuronal activation and subsequent release and action of oxytocin within the CNS. In support of our hypothesis, we found that the effects of lithium against the cannabinoid withdrawal syndrome were antagonized by systemic preapplication of an oxytocin antagonist and mimicked by systemic or intracerebroventricular injection of oxytocin. These results demonstrate that oxytocinergic neuronal activation plays a critical role in the action of lithium against the cannabinoid withdrawal syndrome in rats, thus providing a potentially novel strategy for the treatment of cannabis dependence in humans.
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Brenz Verca MS, Widmer DA, Wagner GC, Dreyer J. Cocaine-induced expression of the tetraspanin CD81 and its relation to hypothalamic function. Mol Cell Neurosci 2001; 17:303-16. [PMID: 11178868 DOI: 10.1006/mcne.2000.0942] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
CD81, a tetraspanin transmembrane protein involved in cell adhesion, was found by differential display to be upregulated in the nucleus accumbens of rat brain following acute cocaine treatment (four injections of 30 mg/kg every 2 h followed by 24 h withdrawal). Cocaine-induced expression of CD81 in adult rat brain was confirmed by quantitative real-time RT-PCR. Its expression in neurons and its function in the brain are unknown. In situ hybridization shows a neuron-specific expression pattern in brain regions functionally related to the regulation of cardiovascular function and fluid homeostasis. CD81 displays codistribution to galanin and, to a lesser extent, to vasopressin. These findings add to data that suggest a connection between the brain reward pathway and the centers regulating endocrine and autonomic functions, in relation to neurochemical, behavioral, and somatic consequences of drug abuse.
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Affiliation(s)
- M S Brenz Verca
- Institute of Biochemistry, University of Fribourg, Fribourg, CH-1700, Switzerland
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