1
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Ollmann T, Lénárd L, Péczely L, Berta B, Kertes E, Zagorácz O, Hormay E, László K, Szabó Á, Gálosi R, Karádi Z, Kállai V. Effect of D1- and D2-like Dopamine Receptor Antagonists on the Rewarding and Anxiolytic Effects of Neurotensin in the Ventral Pallidum. Biomedicines 2022; 10:biomedicines10092104. [PMID: 36140205 PMCID: PMC9495457 DOI: 10.3390/biomedicines10092104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/24/2022] [Accepted: 08/25/2022] [Indexed: 12/04/2022] Open
Abstract
Background: Neurotensin (NT) acts as a neurotransmitter and neuromodulator in the central nervous system. It was shown previously that NT in the ventral pallidum (VP) has rewarding and anxiolytic effects. NT exerts its effect in interaction with dopamine (DA) receptors in numerous brain areas; however, this has not yet been investigated in the VP. The aim of this study was to examine whether the inhibition of D1-like and D2-like DA receptors of the VP can modify the above mentioned effects of NT. Methods: Microinjection cannulas were implanted by means of stereotaxic operations into the VP of male Wistar rats. The rewarding effect of NT was examined by means of a conditioned place preference test. Anxiety was investigated with an elevated plus maze test. To investigate the possible interaction, D1-like DA receptor antagonist SCH23390 or D2-like DA receptor antagonist sulpiride were microinjected prior to NT. All of the drugs were also injected independently to analyze their effects alone. Results: In the present experiments, both the rewarding and anxiolytic effects of NT in the VP were prevented by both D1-like and D2-like DA receptor antagonists. Administered on their own, the antagonists did not influence reward and anxiety. Conclusion: Our present results show that the activity of the D1-like and D2-like DA receptors of the VP is a necessary requirement for both the rewarding and anxiolytic effects of NT.
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Affiliation(s)
- Tamás Ollmann
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
- Correspondence: ; Tel.: +36-72-536000 (ext. 31095)
| | - László Lénárd
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
- Molecular Neuroendocrinology and Neurophysiology Research Group, Szentágothai Center, University of Pécs, H-7624 Pécs, Hungary
| | - László Péczely
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Beáta Berta
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Erika Kertes
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Olga Zagorácz
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Edina Hormay
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Kristóf László
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Ádám Szabó
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Rita Gálosi
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
| | - Zoltán Karádi
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
- Molecular Neuroendocrinology and Neurophysiology Research Group, Szentágothai Center, University of Pécs, H-7624 Pécs, Hungary
| | - Veronika Kállai
- Institute of Physiology, Medical School, University of Pécs, H-7624 Pécs, Hungary
- Centre for Neuroscience, University of Pécs, H-7624 Pécs, Hungary
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2
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Peczely L, Ollmann T, Laszlo K, Lenard L, Grace AA. The D2-like Dopamine Receptor Agonist Quinpirole Microinjected Into the Ventral Pallidum Dose-Dependently Inhibits the VTA and Induces Place Aversion. Int J Neuropsychopharmacol 2022; 25:590-599. [PMID: 35348731 PMCID: PMC9352176 DOI: 10.1093/ijnp/pyac024] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/01/2022] [Accepted: 03/25/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The ventral pallidum (VP) is a dopaminoceptive forebrain structure regulating the ventral tegmental area (VTA) dopaminergic population activity. We have recently demonstrated that in the VP, the D2-like dopamine (DA) receptor agonist quinpirole dose dependently facilitates memory consolidation in inhibitory avoidance and spatial learning. According to our hypothesis, quinpirole microinjected into the VP can modulate the VTA DAergic activity and influence motivation and learning processes of rats. METHODS Quinpirole was microinjected at 3 different doses into the VP of male rats, and controls received vehicle. Single unit recordings were employed to assess VTA DAergic activity. To investigate the possible reinforcing or aversive effect of quinpirole in the VP, the conditioned place preference paradigm was used. RESULTS Our results showed that intra-VP quinpirole microinjection regulates VTA DAergic neurons according to an inverted U-shaped dose-response curve. The largest dose of quinpirole decreased the population activity and strongly reduced burst activity of the DAergic neurons in the first hour after its application. In contrast, the 2 smaller doses increased DA population activity, but their effect started with a delay 1 hour after their microinjection. The CPP experiments revealed that the largest dose of quinpirole in the VP induced place aversion in the rats. Furthermore, the largest dose of quinpirole induced an acute locomotor activity reduction, while the medium dose led to a long-duration increase in locomotion. CONCLUSIONS In summary, quinpirole dose dependently regulates VTA DAergic activity as well as the motivation and motor behavior of the rats at the level of the VP.
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Affiliation(s)
- Laszlo Peczely
- Correspondence: Laszlo Peczely, MD, PhD, Institute of Physiology, Faculty of Medicine, University of Pécs, PO Box 99, H-7602 Pécs, Hungary, Szigeti str. 12 ()
| | - Tamas Ollmann
- Learning in Biological and Artificial Systems Research Group, Institute of Physiology, Pittsburgh, PA, USA,Neuropeptides, Cognition, Animal Models of Neuropsychiatric Disorders Research Group, Institute of Physiology, Pecs, Hungary,Medical School, University of Pecs, Pecs, Hungary,Centre for Neuroscience, Pecs, Hungary,University of Pecs, Pecs, Hungary
| | - Kristof Laszlo
- Neuropeptides, Cognition, Animal Models of Neuropsychiatric Disorders Research Group, Institute of Physiology, Pecs, Hungary,Medical School, University of Pecs, Pecs, Hungary,Centre for Neuroscience, Pecs, Hungary,University of Pecs, Pecs, Hungary
| | - Laszlo Lenard
- Learning in Biological and Artificial Systems Research Group, Institute of Physiology, Pittsburgh, PA, USA,Molecular Neuroendocrinology and Neurophysiology Research Group, Szentagothai Research Centre, Pecs, Hungary
| | - Anthony A Grace
- Departments of Neuroscience, Psychiatry and Psychology, University of Pittsburgh, Pittsburgh, PA, USA
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3
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Schank JR. Neurokinin receptors in drug and alcohol addiction. Brain Res 2020; 1734:146729. [PMID: 32067964 DOI: 10.1016/j.brainres.2020.146729] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 02/03/2020] [Accepted: 02/13/2020] [Indexed: 10/25/2022]
Abstract
The neurokinins are a class of peptide signaling molecules that mediate a range of central and peripheral functions including pain processing, gastrointestinal function, stress responses, and anxiety. Recent data have linked these neuropeptides with drug-related behaviors. Specifically, substance P (SP) and neurokinin B (NKB), have been shown to influence responses to alcohol, cocaine, and/or opiate drugs. SP and NKB preferentially bind to the neurokinin-1 receptor (NK1R) and neurokinin-3 receptor (NK3R), respectively, but do have some affinity for all classes of neurokinin receptor at high concentrations. NK1R activity has been shown to influence reward and reinforcement for opiate drugs, stimulatory and neurochemical responses to cocaine, and escalated and stress-induced alcohol seeking. In reinstatement models of relapse-like behavior, NK1R antagonism attenuates stress-induced reinstatement for all classes of drugs tested to date. The NK3R also influences alcohol intake and behavioral/neurochemical responses to cocaine, but less research has been performed in regard to this particular receptor in preclinical models of addiction. Clinically, agents targeting these receptors have shown some promise, but have produced mixed results. Here, the preclinical findings for the NK1R and NK3R are reviewed, and discussion is provided to interpret clinical findings. Additionally, important factors to consider in regards to future clinical work are suggested.
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Affiliation(s)
- Jesse R Schank
- University of Georgia, Department of Physiology and Pharmacology, 501 DW Brooks Drive, Athens, GA 30602, USA.
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4
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Fazari B, Ilieva Decheva C, González García V, Abdel-Hafiz L, Nikolaus S, Hollenberg CP, Huston JP, de Souza Silva MA, Mattern C. Intranasal pregnenolone increases acetylcholine in frontal cortex, hippocampus, and amygdala-Preferentially in the hemisphere ipsilateral to the injected nostril. J Neurochem 2019; 153:189-202. [PMID: 31755558 DOI: 10.1111/jnc.14923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 11/27/2022]
Abstract
This study determined the effects of intranasal pregnenolone (IN-PREG) on acetylcholine (ACh) levels in selected areas of the rat brain, using in vivo microdialysis. Previous studies showed that PREG rapidly reaches the rodent brain after intranasal administration and that direct infusion of PREG and PREG-S into the basal forebrain modulates ACh release in frontal cortex, amygdala, and hippocampus. In the present study, we investigated the effects of IN-PREG on the cholinergic system in the rat brain. In the first experiment, IN-PREG (5.6 and 11.2 mg/ml) or vehicle was applied bilaterally, and we hypothesized that IN-PREG would increase ACh levels in amygdala, hippocampus, and frontal cortex, relative to baseline and vehicle. Dialysate was collected for 100 min, based on pilot data of duration of effect. Bilateral IN-PREG (5.6 and 11.2 mg/ml) increased frontal cortex and hippocampal ACh relative to both baseline and vehicle. Moreover, 11.2 mg/ml PREG increased ACh in the amygdala relative to baseline, the lower dose, and vehicle. Therefore, in the second experiment, IN-PREG (11.2 mg/ml) was applied only into one nostril, with vehicle applied into the other nostril, in order to determine whether ACh is predominantly increased in the ipsilateral relative to the contralateral amygdala. Unilateral application of IN-PREG increased ACh in the ipsilateral amygdala, whereas no effect was observed on the contralateral side, suggesting that PREG was transported from the nostrils to the brain via the olfactory epithelial pathway, but not by circulation. The present data provide additional information on IN-PREG action in the cholinergic system of frontal cortex, amygdala, and hippocampus. This may be relevant for therapeutic IN application of PREG in neurogenerative and neuropsychiatric disorders.
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Affiliation(s)
- Benedetta Fazari
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Cvetana Ilieva Decheva
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Victoria González García
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Laila Abdel-Hafiz
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.,Institute of Anatomy II, Medical Faculty, Heinrich Heine Universität, Düsseldorf, Germany
| | - Susanne Nikolaus
- Clinic of Nuclear Medicine, University Hospital Düsseldorf, Düsseldorf, Germany
| | - Cornelis P Hollenberg
- Institute of Microbiology, Heinrich Heine Universität Düsseldorf, Düsseldorf, Germany
| | - Joseph P Huston
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Maria A de Souza Silva
- Center for Behavioral Neuroscience, Institute of Experimental Psychology, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Claudia Mattern
- M et P Pharma AG, Emetten, Switzerland.,Oceanographic Center, Nova Southeastern University, Fort Lauderdale, FL, USA
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5
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The role of intraamygdaloid neurotensin and dopamine interaction in conditioned place preference. Behav Brain Res 2018; 344:85-90. [DOI: 10.1016/j.bbr.2018.01.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 01/18/2018] [Accepted: 01/19/2018] [Indexed: 01/21/2023]
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6
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Lénárd L, László K, Kertes E, Ollmann T, Péczely L, Kovács A, Kállai V, Zagorácz O, Gálosi R, Karádi Z. Substance P and neurotensin in the limbic system: Their roles in reinforcement and memory consolidation. Neurosci Biobehav Rev 2018; 85:1-20. [DOI: 10.1016/j.neubiorev.2017.09.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 08/24/2017] [Accepted: 09/02/2017] [Indexed: 12/18/2022]
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7
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Ubaldi M, Cannella N, Ciccocioppo R. Emerging targets for addiction neuropharmacology: From mechanisms to therapeutics. PROGRESS IN BRAIN RESEARCH 2015; 224:251-84. [PMID: 26822362 DOI: 10.1016/bs.pbr.2015.07.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Drug abuse represents a considerable burden of disease and has enormous economic impacts on societies. Over the years, few medications have been developed for clinical use. Their utilization is endowed with several limitations, including partial efficacy or significant side effects. On the other hand, the successful advancement of these compounds provides an important proof of concept for the feasibility of drug development programs in addiction. In recent years, a wealth of information has been generated on the psychological mechanisms, genetic or epigenetic predisposing factors, and neurobiological adaptations induced by drug consumption that interact with each other to contribute to disease progression. It is now clear that addiction develops through phases, from initial recreational use to excessive consumption and compulsive drug seeking, with a shift from positive to negative reinforcement driving motivated behaviors. A greater understanding of these mechanisms has opened new vistas in drug development programs. Researchers' attention has been shifted from investigation of classical targets associated with reward to biological substrates responsible for negative reinforcement, impulse loss of control, and maladaptive mechanisms resulting from protracted drug use. From this research, several new biological targets for the development of innovative therapies have started to emerge. This chapter offers an overview of targets currently under scrutiny for the development of new medications for addiction. This work is not exhaustive but rather it provides a few examples of how this research has advanced in recent years by virtue of studies carried out in our laboratory.
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Affiliation(s)
- Massimo Ubaldi
- School of Pharmacy, Pharmacology Unit, University of Camerino, Camerino, Italy
| | - Nazzareno Cannella
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
| | - Roberto Ciccocioppo
- School of Pharmacy, Pharmacology Unit, University of Camerino, Camerino, Italy.
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8
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Sandweiss AJ, Vanderah TW. The pharmacology of neurokinin receptors in addiction: prospects for therapy. Subst Abuse Rehabil 2015; 6:93-102. [PMID: 26379454 PMCID: PMC4567173 DOI: 10.2147/sar.s70350] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Addiction is a chronic disorder in which consumption of a substance or a habitual behavior becomes compulsive and often recurrent, despite adverse consequences. Substance p (SP) is an undecapeptide and was the first neuropeptide of the neurokinin family to be discovered. The subsequent decades of research after its discovery implicated SP and its neurokinin relatives as neurotransmitters involved in the modulation of the reward pathway. Here, we review the neurokinin literature, giving a brief historical perspective of neurokinin pharmacology, localization in various brain regions involved in addictive behaviors, and the functional aspects of neurokinin pharmacology in relation to reward in preclinical models of addiction that have shaped the rational drug design of neurokinin antagonists that could translate into human research. Finally, we will cover the clinical investigations using neurokinin antagonists and discuss their potential as a therapy for drug abuse.
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Affiliation(s)
- Alexander J Sandweiss
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Todd W Vanderah
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ, USA
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9
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Dopamine in the nucleus accumbens core, but not shell, increases during signaled food reward and decreases during delayed extinction. Neurobiol Learn Mem 2015; 123:125-39. [DOI: 10.1016/j.nlm.2015.06.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 05/29/2015] [Accepted: 06/01/2015] [Indexed: 11/18/2022]
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10
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Martinez RC, Hamani C, de Carvalho MC, de Oliveira AR, Alho E, Navarro J, dos Santos Ghilardi MG, Bor-Seng-Shu E, Heinsen H, Otoch JP, Brandão ML, Barbosa ER, Teixeira MJ, Fonoff ET. Intraoperative dopamine release during globus pallidus internus stimulation in Parkinson's disease. Mov Disord 2013; 28:2027-32. [DOI: 10.1002/mds.25691] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 08/15/2013] [Accepted: 08/22/2013] [Indexed: 12/24/2022] Open
Affiliation(s)
- Raquel C.R. Martinez
- Laboratory of Neuromodulation and Experimental Pain; Hospital Sirio-Libanes São Paulo Brazil
- University of São Paulo and Institute of Neuroscience and Behavior (INeC); Campus USP Ribeirao Preto Brazil
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
- Department of Surgery, Discipline of Surgical Technique; School of Medicine, University of São Paulo; LIM 26 HC-FMUSP São Paulo Brazil
| | - Clement Hamani
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
| | | | - Amanda Ribeiro de Oliveira
- University of São Paulo and Institute of Neuroscience and Behavior (INeC); Campus USP Ribeirao Preto Brazil
| | - Eduardo Alho
- Labor für Morphologische Hirnforschung (Laboratory for Morphological Brain Research); Julius-Maximilians Universität Würzburg; Würzburg Germany
| | - Jessie Navarro
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
| | - Maria Gabriela dos Santos Ghilardi
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
| | - Edson Bor-Seng-Shu
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
| | - Helmut Heinsen
- Labor für Morphologische Hirnforschung (Laboratory for Morphological Brain Research); Julius-Maximilians Universität Würzburg; Würzburg Germany
| | - José Pinhata Otoch
- Department of Surgery, Discipline of Surgical Technique; School of Medicine, University of São Paulo; LIM 26 HC-FMUSP São Paulo Brazil
| | - Marcus Lira Brandão
- University of São Paulo and Institute of Neuroscience and Behavior (INeC); Campus USP Ribeirao Preto Brazil
| | - Egberto Reis Barbosa
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
| | - Manoel Jacobsen Teixeira
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
- Department of Surgery, Discipline of Surgical Technique; School of Medicine, University of São Paulo; LIM 26 HC-FMUSP São Paulo Brazil
| | - Erich Talamoni Fonoff
- Department of Neurology, Division of Functional Neurosurgery; Institute of Psychiatry; University of São Paulo School of Medicine; São Paulo Brazil
- Department of Surgery, Discipline of Surgical Technique; School of Medicine, University of São Paulo; LIM 26 HC-FMUSP São Paulo Brazil
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11
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Schank JR, Ryabinin AE, Giardino WJ, Ciccocioppo R, Heilig M. Stress-related neuropeptides and addictive behaviors: beyond the usual suspects. Neuron 2012; 76:192-208. [PMID: 23040815 PMCID: PMC3495179 DOI: 10.1016/j.neuron.2012.09.026] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Addictive disorders are chronic, relapsing conditions that cause extensive disease burden. Genetic factors partly account for susceptibility to addiction, but environmental factors such as stressful experiences and prolonged exposure of the brain to addictive drugs promote its development. Progression to addiction involves neuroadaptations within neurocircuitry that mediates stress responses and is influenced by several peptidergic neuromodulators. While corticotrophin releasing factor is the prototypic member of this class, recent work has identified several additional stress-related neuropeptides that play an important role in regulation of drug intake and relapse, including the urocortins, nociceptin, substance P, and neuropeptide S. Here, we review this emerging literature, discussing to what extent the properties of these neuromodulators are shared or distinct and considering their potential as drug targets.
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Affiliation(s)
- Jesse R. Schank
- Laboratory of Clinical and Translational Studies, National Inst. on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892
| | - Andrey E. Ryabinin
- Dept. of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239-3098
| | - William J. Giardino
- Dept. of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR 97239-3098
| | - Roberto Ciccocioppo
- Dept. of Experimental Medicine and Public Health, Camerino University, Italy
| | - Markus Heilig
- Laboratory of Clinical and Translational Studies, National Inst. on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892
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12
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Potentiation of brain stimulation reward by morphine: effects of neurokinin-1 receptor antagonism. Psychopharmacology (Berl) 2012; 220:215-24. [PMID: 21909635 PMCID: PMC3484369 DOI: 10.1007/s00213-011-2469-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 08/23/2011] [Indexed: 10/17/2022]
Abstract
RATIONALE The abuse potential of opioids may be due to their reinforcing and rewarding effects, which may be attenuated by neurokinin-1 receptor (NK1R) antagonists. OBJECTIVE This study was conducted to measure the effects of opioid and NK1R blockade on the potentiation of brain stimulation reward (BSR) by morphine using the intracranial self-stimulation method. METHODS Adult male C57BL/6J mice (n = 15) were implanted with unipolar stimulating electrodes in the lateral hypothalamus and trained to respond for varying frequencies of rewarding electrical stimulation. The BSR threshold (θ(0)) and maximum response rate (MAX) were determined before and after intraperitoneal administration of saline, morphine (1.0-17.0 mg/kg), or the NK1R antagonists L-733,060 (1.0-17.0 mg/kg) and L-703,606 (1.0-17.0 mg/kg). In morphine antagonism experiments, naltrexone (0.1-1.0 mg/kg) or 10.0 mg/kg L-733,060 or L-703,606 was administered 15 min before morphine (1.0-10.0 mg/kg) or saline. RESULTS Morphine dose-dependently decreased θ(0) (maximum effect = 62% of baseline) and altered MAX when compared to saline. L-703,606 and L-733,060 altered θ(0); 10.0 mg/kg L-733,060 and L-703,606, which did not affect θ(0) or MAX, attenuated the effects of 3.0 and 10.0 mg/kg morphine, and 1.0 and 0.3 mg/kg naltrexone blocked the effects of 10.0 mg/kg morphine. Naltrexone given before saline did not affect θ(0) or MAX. CONCLUSIONS The decrease in θ(0) by morphine reflects its rewarding effects, which were attenuated by NK1R and opioid receptor blockade. These results demonstrate the importance of substance P signaling during limbic reward system activation by opioids.
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13
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Karrenbauer B, Müller C, Ho Y, Spanagel R, Huston J, Schwarting R, Pawlak C. Time-dependent in-vivo effects of interleukin-2 on neurotransmitters in various cortices: Relationships with depressive-related and anxiety-like behaviour. J Neuroimmunol 2011; 237:23-32. [DOI: 10.1016/j.jneuroim.2011.05.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 04/27/2011] [Accepted: 05/24/2011] [Indexed: 01/18/2023]
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14
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Kertes E, László K, Berta B, Lénárd L. Positive reinforcing effects of substance P in the rat globus pallidus revealed by conditioned place preference. Behav Brain Res 2010; 215:152-5. [DOI: 10.1016/j.bbr.2010.06.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Accepted: 06/21/2010] [Indexed: 11/26/2022]
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15
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Facilitation of 5-HT1A-mediated neurotransmission in dorsal periaqueductal grey matter accounts for the panicolytic-like effect of chronic fluoxetine. Int J Neuropsychopharmacol 2010; 13:1079-88. [PMID: 19941697 DOI: 10.1017/s146114570999099x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chronic administration of antidepressants such as fluoxetine and imipramine increases the responsiveness of 5-HT(1A) receptors in dorsal periaqueductal grey matter (DPAG), a midbrain area consistently implicated in the pathogenesis of panic disorder. This effect has been related to the clinically relevant anti-panic action of these drugs. In this study we determined whether long-term administration of fluoxetine also affects 5-HT efflux in DPAG. As a comparison, the effect of chronic treatment with the anxiolytic 5-HT(1A) receptor agonist buspirone on DPAG 5-HT levels was assessed. We also investigated whether the inhibitory effect of chronic fluoxetine on escape behaviour in the rat elevated T-maze, considered as a panicolytic-like effect, is counteracted by intra-DPAG injection of the 5-HT(1A) receptor antagonist WAY 100635. Male Wistar rats were treated (1 or 21 d, i.p.) with fluoxetine, buspirone or vehicle, once daily. After treatment, 5-HT in DPAG was measured by in-vivo microdialysis coupled to HPLC. In another study, rats treated (21 d, i.p.) with either fluoxetine or vehicle also received intra-DPAG injection of WAY 100635 or saline 10 min before being tested in the elevated T-maze. Chronic, but not acute, administration of fluoxetine significantly raised extracellular levels of 5-HT in DPAG. Long-term treatment with buspirone was ineffective. In the elevated T-maze, intra-DPAG injection of WAY 100635 fully blocked the anti-escape effect of chronic administration of fluoxetine. Therefore, chronic fluoxetine facilitates 5-HT(1A)-mediated neurotransmission within DPAG and this effect accounts for the panicolytic-like effect of this antidepressant in the elevated T-maze.
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Kertes E, László K, Berta B, Lénárd L. Positive reinforcing effects of substance P in the rat central nucleus of amygdala. Behav Brain Res 2009; 205:307-10. [DOI: 10.1016/j.bbr.2009.06.028] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 06/15/2009] [Accepted: 06/17/2009] [Indexed: 10/20/2022]
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17
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Extracellular serotonin level in the basolateral nucleus of the amygdala and dorsal periaqueductal gray under unconditioned and conditioned fear states: An in vivo microdialysis study. Brain Res 2009; 1294:106-15. [DOI: 10.1016/j.brainres.2009.07.074] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 07/21/2009] [Accepted: 07/22/2009] [Indexed: 11/20/2022]
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18
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de Souza Silva MA, Mattern C, Topic B, Buddenberg TE, Huston JP. Dopaminergic and serotonergic activity in neostriatum and nucleus accumbens enhanced by intranasal administration of testosterone. Eur Neuropsychopharmacol 2009; 19:53-63. [PMID: 18818056 DOI: 10.1016/j.euroneuro.2008.08.003] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 08/01/2008] [Accepted: 08/12/2008] [Indexed: 12/01/2022]
Abstract
Testosterone was administered intranasally in anesthetized male rats, and its effects on the activity of dopaminergic and serotonergic neurons in the neostriatum and nucleus accumbens were assessed by means of microdialysis and HPLC. The treatment (0.5, 1.0 or 2.0 mg/kg of testosterone or vehicle, 10 microl volume) was applied in both nostrils, half (5 microl) into each. Subcutaneous injections of testosterone (2.0, 4.0 or 8.0 mg/kg) or vehicle were tested in other subjects. Samples were collected for 5 h. In the neostriatum, an increase of dopamine occurred after 2.0 mg/kg. Serotonin levels increased after 1.0 mg/kg dose. In the nucleus accumbens, dopamine and serotonin increased after 1.0 mg/kg and 2.0 mg/kg doses. Subcutaneous administration of 8.0 mg/kg testosterone increased dopamine and serotonin in the neostriatum only. We conclude that intranasal administration of testosterone is a more efficacious way for targeting the brain than the subcutaneous route, and may be considered as a means to activate central dopaminergic and serotonergic systems.
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Affiliation(s)
- M A de Souza Silva
- Institute of Physiological Psychology and Center for Biological and Medical Research, University of Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany.
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Silva MADS, Jocham G, Barros M, Tomaz C, Müller CP. Neurokinin3 receptor modulation of the behavioral and neurochemical effects of cocaine in rats and monkeys. Rev Neurosci 2008; 19:101-11. [PMID: 18751518 DOI: 10.1515/revneuro.2008.19.2-3.101] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Neurokinin3 (NK3) receptors and their endogenous ligands (e.g. the neuropeptide substance P and its C-terminal fragment) have been implicated in psychomotor activity and reinforcement mechanisms. We review here recent findings on the involvement of NK3 receptors in the behavioral and neurochemical effects of cocaine. Although NK3 receptors can modulate dopamine (DA) activity in the brain, recent results suggest that this modulation does not occur during spontaneous behavioral activity. However, NK3 receptors play a role in the regulation of cocaine-induced DA responses in the nucleus accumbens core and shell subregions. NK3 receptor agonism as well as antagonism potentiate cocaine's effects on nucleus accumbens DA subregions specifically, and modulate the acute behavioral effects of cocaine in rats and non-human primates (Callithrix penicillata). However, conditioned place preference studies in rats have, so far, failed to provide evidence for an involvement of NK3 receptors in the reinforcing effects of cocaine.
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Budilin SY, Midzyanovskaya IS, Shchegolevskii NV, Ioffe ME, Bazyan AS. Asymmetry in dopamine levels in the nucleus accumbens and motor preference in rats. ACTA ACUST UNITED AC 2008; 38:991-4. [DOI: 10.1007/s11055-008-9082-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2007] [Accepted: 06/18/2007] [Indexed: 11/25/2022]
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21
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de Souza Silva MA, Topic B, Huston JP, Mattern C. Intranasal administration of progesterone increases dopaminergic activity in amygdala and neostriatum of male rats. Neuroscience 2008; 157:196-203. [PMID: 18824215 DOI: 10.1016/j.neuroscience.2008.09.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 09/02/2008] [Accepted: 09/03/2008] [Indexed: 11/29/2022]
Abstract
We evaluated the effects of intranasal administration of progesterone (PROG) on the activity of dopaminergic neurons in the brain of anesthetized rats by means of microdialysis. Male Wistar rats were implanted with guide cannulae in the basolateral amygdala and neostriatum. Three to 5 days later, they were anesthetized with urethane, and dialysis probes were inserted. After a stabilization period of 2 h, four 30-min samples were collected. Thereafter, the treatment (0.5, 1.0 or 2.0 mg/kg of PROG dissolved in a viscous castor oil mixture, or vehicle) was applied into the nose in a volume of 10 microl (5 microl in each nostril). In other animals, an s.c. injection of PROG (1.0, 2.0 or 4.0 mg/kg) or vehicle was given. Samples of both application ways were collected at 30-min interval for 4 h after the treatment and immediately analyzed with high performance liquid chromatography and electrochemical detection. Intranasal administration of 2 mg/kg of PROG led to an immediate (within 30 min after the treatment) significant increase in the basolateral amygdala dopamine levels. In the neostriatum, the 2 mg/kg dose led to a delayed significant increase in dopamine. S.c. administration of 4 mg/kg of PROG was followed by a delayed significant increase in dopamine, both, in the basolateral amygdala and neostriatum, but smaller in magnitude in comparison to the intranasal treatment. This is the first study to demonstrate dopamine-enhancing effects of PROG, not only in the neostriatum, but also in the basolateral amygdala. Our results indicate that the intranasal route of administration of PROG is a more efficacious way for targeting the brain than the s.c. route.
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Affiliation(s)
- M A de Souza Silva
- Institute of Physiological Psychology and Center for Biological and Medical Research, University of Düsseldorf, Universitätsstr. 1, D-40225 Düsseldorf, Germany.
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22
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Carvalho MC, Masson S, Brandão ML, de Souza Silva MA. Anxiolytic-like effects of substance P administration into the dorsal, but not ventral, hippocampus and its influence on serotonin. Peptides 2008; 29:1191-200. [PMID: 18490080 DOI: 10.1016/j.peptides.2008.02.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 02/18/2008] [Accepted: 02/20/2008] [Indexed: 10/22/2022]
Abstract
Substance P (SP) is known to be involved in processes related to learning and memory, fear, anxiety and stress. SP and NK1 receptors are localized in the hippocampus, a brain structure involved in learning and memory as well as emotional processes. As there is evidence for differential functions of the ventral (VH) and dorsal (DH) hippocampus in a variety of behaviors, we here evaluated the effects of injections of SP into the VH and DH in rats submitted to the elevated plus-maze (EPM) and open field (OF) tests. The results obtained showed that infusions of 100 and 1000 ng of SP into the DH, but not VH, increased open arm activity in the EPM and in the central zone of the OF, indicative of anxiolytic-like action. These effects were observed in the absence of significant changes in general motor activity. In an additional experiment to examine whether these effects of SP are mediated by local serotoninergic mechanisms, extracellular concentrations of this monoamine were assessed by use of in vivo microdialysis. Infusions of SP into the DH did not influence the extracellular concentration of serotonin. These data indicate that neurokinins in the DH, but not VH, are involved in mechanisms associated with anxiety and that the mediation of SP in anxiety-related behaviors is independent of local serotonergic mechanisms.
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Affiliation(s)
- M C Carvalho
- Instituto de Neurociências e Comportamento (INeC), Campus USP, 14040-901 Ribeirão Preto, SP, Brazil
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Pum ME, Huston JP, De Souza Silva MA, Müller CP. Visual sensory-motor gating by serotonin activation in the medial prefrontal and occipital, but not in the rhinal, cortices in rats. Neuroscience 2008; 153:361-72. [PMID: 18378406 DOI: 10.1016/j.neuroscience.2008.02.029] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Revised: 02/11/2008] [Accepted: 02/20/2008] [Indexed: 11/26/2022]
Abstract
A behavioral reaction to sensory stimulation is a basic mechanism which is pivotal to many complex behavioral responses. In previous studies we found that visual stimulation induces a selective serotonergic and dopaminergic activation in the occipital (OccC), but not temporal (TempC) cortex in freely moving rats. In a behavioral study in rats we demonstrate now that visual stimulation (0, 8, 22, 82, 155 or 440 lux) activates behavioral activity in an intensity-dependent manner. Behavior activating visual stimulation with 82 lux, but not 22 lux or 82 dB white noise, increased extracellular serotonin (5-HT), but not dopamine (DA), in the medial prefrontal cortex (mPFC) in freely moving animals measured by in vivo microdialysis. There was no effect on 5-HT or DA in the entorhinal and perirhinal cortex. Visual stimulation with 82 lux increased extracellular 5-HT in the mPFC and OccC also in anesthetized animals, but had no effect in the TempC. Auditory stimulation reduced 5-HT in the TempC, but had no effect in the mPFC or OccC. Neither visual nor auditory stimulation had a significant effect on DA in all three cortical areas. We conclude that visual stimulation induces behavioral activation by increasing 5-HT activity in the mPFC and OccC.
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Affiliation(s)
- M E Pum
- Institute of Physiological Psychology and Center for Biological and Medical Research, University of Düsseldorf, Universitätsstrasse 1, Düsseldorf, Germany
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Karakuyu D, Herold C, Güntürkün O, Diekamp B. Differential increase of extracellular dopamine and serotonin in the ‘prefrontal cortex’ and striatum of pigeons during working memory. Eur J Neurosci 2007; 26:2293-302. [PMID: 17908172 DOI: 10.1111/j.1460-9568.2007.05840.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Monoamines, such as dopamine (DA) and serotonin (5-HT), play a central role in the modulation of cognitive processes at the forebrain level. Experimental and clinical studies based on dopaminergic pathology, depletion or medication indicate that DA, in particular, is involved in working memory (WM). However, it is unclear whether DA is indeed related to WM, whether its function is specific to the prefrontal cortex (PFC), and whether other modulators, such as 5-HT, might have similar functions. Therefore, the aims of this study were threefold. First, we analysed whether increased prefrontal DA release is related to WM in general or only to its short-term memory component. Second, we examined whether the DA release during cognitive tasks is specific to prefrontal areas or also occurs in the striatum. Third, we analysed whether prefrontal or striatal 5-HT release accompanies working and short-term memory. We approached these questions by using in vivo microdialysis to analyse the extracellular DA and 5-HT release in the pigeons' 'PFC' and striatum during matching-to-sample tasks with or without a delay. Here, we show that DA has no unitary function but is differentially released during working as well as short-term memory in the pigeons' 'prefrontal' cortex. Striatal DA shows an increased efflux only during WM that involves a delay component. WM is also accompanied by a 'prefrontal' but not a striatal release of 5-HT, whose efflux pattern is thus partly different to that of DA. Our findings thus show a triple dissociation between transmitters, structures and tasks within the avian 'prefronto'-striatal system.
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Affiliation(s)
- Dilek Karakuyu
- Biopsychologie, Fakultät für Psychologie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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Pum M, Carey RJ, Huston JP, Müller CP. Dissociating effects of cocaine and d-amphetamine on dopamine and serotonin in the perirhinal, entorhinal, and prefrontal cortex of freely moving rats. Psychopharmacology (Berl) 2007; 193:375-90. [PMID: 17468969 DOI: 10.1007/s00213-007-0791-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Accepted: 04/03/2007] [Indexed: 02/06/2023]
Abstract
RATIONALE Neuroimaging studies with humans showed widespread activation of the cortex in response to psychostimulant drugs. However, the neurochemical nature of these brain activities is not characterized. OBJECTIVE The aim of the present study was to investigate the effects of cocaine and d-amphetamine on dopamine (DA) and serotonin (5-HT) in cortical areas of the hippocampal network in comparison to the prefrontal cortex (PFC). MATERIALS AND METHODS We conducted in vivo microdialysis experiments in behaving rats measuring DA and 5-HT in the perirhinal cortex (PRC), entorhinal cortex (EC), and PFC, after application of cocaine (0, 5, 10, 20 mg/kg; i.p.) or d-amphetamine (0, 0.5, 1.0, 2.5 mg/kg; i.p.). RESULTS Cocaine and d-amphetamine dose-dependently increased DA and 5-HT levels in the PRC, EC, and PFC. A predominant DA response to d-amphetamine was only found in the PFC, but not in the PRC and EC. Cocaine increased DA and 5-HT to an equal extent in the PFC and PRC but induced a predominant 5-HT response in the EC. When comparing the neurochemical responses between the drugs at an equal level of behavioral activation, cocaine was more potent than d-amphetamine in increasing 5-HT in the PFC, while no differences were found in the PRC or EC or in the DA responses in all three cortical areas. CONCLUSIONS We conclude that cocaine and d-amphetamine increase DA and 5-HT levels in PRC and EC largely to the same extent as in the PFC.
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Affiliation(s)
- M Pum
- Institute of Physiological Psychology and Center for Biological and Medical Research, University of Düsseldorf, Düsseldorf, Germany
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26
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Jocham G, Lauber AC, Müller CP, Huston JP, de Souza Silva MA. Neurokinin 3 receptor activation potentiates the psychomotor and nucleus accumbens dopamine response to cocaine, but not its place conditioning effects. Eur J Neurosci 2007; 25:2457-72. [PMID: 17445241 DOI: 10.1111/j.1460-9568.2007.05491.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Neurokinin(3) receptors (NK(3)-Rs) have been implicated in psychomotor activity and reinforcement mechanisms. Recently, we showed that NK(3)-R antagonism blocked the psychostimulant properties of cocaine both in rats and in primates. Here, using in vivo microdialysis in the nucleus accumbens (NAc) of freely moving rats, we investigated the effect of the NK(3)-R agonist senktide (0.2 and 0.4 mg/kg s.c.) on the cocaine-evoked increase in dopamine. Cocaine (10 mg/kg i.p.) increased dopamine levels to 404 and 480% of baseline in the core and shell of the NAc, respectively. Pretreatment with senktide at a dose of 0.2 mg/kg potentiated this effect to 666 (core) and 869% (shell) of baseline, without having any effect on dopamine when given alone. Behavioural measurements revealed that 0.2 mg/kg senktide also potentiated the cocaine-induced increase in horizontal and vertical activity. Senktide alone induced a short-lasting increase in activity that was not accompanied by any alterations of the neurochemical parameters. In conditioned place preference (CPP) experiments, senktide pretreatment did not alter CPP induced by cocaine (5 and 10 mg/kg i.p.), and had no effect when given alone. Likewise, cocaine-conditioned locomotor activity was not affected by the NK(3)-R agonist. However, as in the microdialysis studies, cocaine-induced (5 and 10 mg/kg i.p.) hyperactivity was potentiated by senktide, and there was evidence for a facilitation of sensitization to the hyperlocomotor effects of cocaine by senktide. These data provide evidence that NK(3)-Rs are involved in the control of the hyperlocomotor and NAc DA response to cocaine, but not in cocaine-induced CPP.
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Affiliation(s)
- Gerhard Jocham
- Institute of Physiological Psychology and Center for Biological and Medical Research, University of Düsseldorf, Universitätsstr. 1, D-40225, Düsseldorf, Germany
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Müller CP, Huston JP. Dopamine activity in the occipital and temporal cortices of rats: dissociating effects of sensory but not pharmacological stimulation. Synapse 2007; 61:254-8. [PMID: 17230551 DOI: 10.1002/syn.20366] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Little is known about the functional role of DA in other cortical areas than in the prefrontal cortex. Here we demonstrate that visual stimulation increases DA activity as measured by in vivo microdialysis in the occipital, but not in the temporal cortex of freely moving rats. Auditory stimulation neither acutely affected DA in the occipital nor in the temporal cortex. A pharmacological challenge with cocaine (0, 5, 10, 20 mg/kg; i.p.) increased DA levels in both areas dose-dependently. These data suggest that DA might play a role in visual processing selectively in the occipital cortex. Furthermore, the results indicate that DA in both regions may contribute to cocaine's behavioral effects.
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Affiliation(s)
- Christian P Müller
- Institute of Physiological Psychology and Center for Biological and Medical Research, University of Düsseldorf, Düsseldorf, Germany.
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Ota K, Kitazono T, Ooboshi H, Kamouchi M, Katafuchi T, Aou S, Yamashita Y, Ibayashi S, Iida M. Role of substantia innominata in cerebral blood flow autoregulation. Brain Res 2007; 1135:146-53. [PMID: 17196949 DOI: 10.1016/j.brainres.2006.12.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 11/27/2006] [Accepted: 12/07/2006] [Indexed: 11/25/2022]
Abstract
Ascending projections from the substantia innominata (SI) may have an important role in the regulation of cerebral blood flow (CBF). However, several reports have suggested that unilateral lesion of the SI does not affect CBF autoregulation. On the other hand, it is also reported that several cortical and subcortical functions may be regulated not only by ipsilateral SI, but also by contralateral SI. Thus, the objective of this study is to test the hypothesis that bilateral lesions of the SI affect CBF autoregulation. Experiments were performed on anesthetized male Sprague-Dawley rats. Ibotenic acid or physiological saline was microinjected into bilateral SI. Rats were classified into four groups as follows: bilateral SI lesion rats (ibotenic acid was injected bilaterally), left or right SI lesion rats (ibotenic acid was injected into the unilateral SI and saline into the contralateral SI), and control rats (saline was injected bilaterally). Ten days after injection, CBF in the left frontal cortex was measured by laser-Doppler flowmetry during stepwise controlled hemorrhagic hypotension. In bilateral SI lesion rats, CBF was started to decrease significantly at 80 mm Hg (p<0.01). In the other three groups, CBF was well maintained until 50 mm Hg. Changes in CBF through stepwise hypotension in bilateral SI lesion rats were significantly different from the other groups (p<0.01). These results suggest that bilateral SI regulates cortical vasodilator mechanisms during hemorrhagic hypotension. Under unilateral SI lesion, some compensatory effects from the contralateral SI may maintain CBF autoregulation.
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Affiliation(s)
- Kazuki Ota
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
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Jocham G, Lezoch K, Müller CP, Kart-Teke E, Huston JP, de Souza Silva MA. Neurokinin receptor antagonism attenuates cocaine's behavioural activating effects yet potentiates its dopamine-enhancing action in the nucleus accumbens core. Eur J Neurosci 2007; 24:1721-32. [PMID: 17004936 DOI: 10.1111/j.1460-9568.2006.05041.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Several lines of evidence indicate a role for neurokinin3 receptors (NK3-Rs) in behavioural activation and mechanisms governing reinforcement processes. In this study we investigated the effect of pretreatment with the NK3-R antagonist, SR142801, (0.2 and 2.0 mg/kg) on the cocaine-induced (10.0 mg/kg i.p.) increase in extracellular dopaminergic activity in the nucleus accumbens (NAc). In vivo microdialysis in the NAc of freely moving rats showed that cocaine increased concentrations of dopamine (DA) to approximately 350% in the core and approximately 450% in the shell. Pre-treatment with SR142801 significantly potentiated this effect in the core (to approximately 550%), whereas this effect was not found in the shell. We also investigated the effects of NK3-Rs antagonism on cocaine-induced hyperactivity and conditioned place preference. SR142801 blocked the hyperactivity, but neither the conditioned place preference nor the conditioned locomotor activity induced by cocaine, although there was a slight tendency towards a reduced place preference. When given alone, SR142801 had no effects on behaviour or extracellular dopamine concentrations in any of the structures investigated. These data provide evidence for a contribution of NK3-Rs in the acute behavioural and neurochemical effects of cocaine, involving dopaminergic activity in the core of the nucleus accumbens.
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Affiliation(s)
- Gerhard Jocham
- Institute of Physiological Psychology and Center for Biological and Medical Research, University of Düsseldorf, Universitätsstr.1, D-40225, Düsseldorf, Germany.
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Müller CP, De Souza Silva MA, Huston JP. Double dissociating effects of sensory stimulation and cocaine on serotonin activity in the occipital and temporal cortices. Neuropharmacology 2006; 52:854-62. [PMID: 17116310 DOI: 10.1016/j.neuropharm.2006.10.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 09/26/2006] [Accepted: 10/09/2006] [Indexed: 11/18/2022]
Abstract
Visual cues that become associated with the consumption of psychostimulant drugs energize craving and the intake of the drug by mechanisms of which little is known. In two experiments using in vivo microdialysis in freely moving rats we compared the effects of visual and auditory stimulation with that of cocaine (0, 5, 10, 20mg/kg; i.p.) on the extracellular serotonin (5-HT) activity in the occipital and temporal cortices in relation to behavior. Visual stimulation increased 5-HT in the occipital, but not temporal cortex, parallel to an increase in locomotion. Auditory stimulation decreased 5-HT in the auditory, but not occipital cortex, thus, showing a double dissociated 5-HT response. These data suggest that a locally restricted 5-HT response to sensory stimulation may gate behavioral activity sense-modality selectively. Cocaine affected 5-HT in the occipital cortex and behavioral activity in the same direction as visual stimulation, but in an amplified and prolonged way. In the temporal cortex cocaine also caused an increase in 5-HT. The findings demonstrate common effects of visual stimulation and cocaine on 5-HT activity in the occipital cortex in relation to locomotor activity. The results suggest that concepts of how neutral visual cues become powerful energizers of addiction-related behaviors should be expanded to incorporate not only an acute enhancement of reward processing mechanisms, but, in parallel, also an amplified processing of visual stimuli in the occipital cortex.
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Affiliation(s)
- Christian P Müller
- Institute of Physiological Psychology I, Centre for Biological and Medical Research, University of Düsseldorf, Universitätsstrasse 1, 40225 Düsseldorf, Germany.
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31
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Zarrindast MR, Moghimi M, Rostami P, Rezayof A. Histaminergic receptors of medial septum and conditioned place preference: D1 dopamine receptor mechanism. Brain Res 2006; 1109:108-16. [PMID: 16828718 DOI: 10.1016/j.brainres.2006.06.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2005] [Revised: 06/06/2006] [Accepted: 06/12/2006] [Indexed: 10/24/2022]
Abstract
In the present study, the effects of intra-medial septum injections of histamine and/or the histamine H1 or H2 receptor antagonists on the acquisition of conditioned place preference (CPP) in male Wistar rats have been investigated. Our data showed that the conditioning treatments with intra-medial septum injection of different doses of histamine (0.5-15 microg/rat) induced a significant CPP for the drug-associated place. Using a 3-day schedule of conditioning, it was found that the histamine H1 receptor antagonist, pyrilamine (10 and 15 microg/rat, intra-medial septum) also induced a significant place preference. In addition, pyrilamine inhibited the histamine (7.5 microg/rat)-induced place preference. Intra-medial septum administration of the histamine H2 receptor antagonist, ranitidine (5-15 microg/rat) alone or in combination with histamine did not produce a significant place preference or place aversion. On the other hand, intra-medial septum administration of the dopamine D1 receptor antagonist, SCH 233390 (0.5, 0.75 and 1 microg/rat) inhibited the histamine (7.5 microg/rat) or pyrilamine (15 microg/rat)-induced place preference in a dose-dependent manner, but no effect was observed for the dopamine D2 receptor antagonist, sulpiride on the histamine or pyrilamine response. The administration of histamine (2.5-15 microg/rat) or pyrilamine (10 and 15 microg/rat) during acquisition increased locomotor activity of the animals on the testing days. The results suggest that histaminergic receptors of the medial septum may be involved in CPP and thus it is postulated that dopamine D1 receptors may play an important role in this effect.
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Affiliation(s)
- Mohammad-Reza Zarrindast
- Department of Pharmacology and Iranian National Center for Addiction Studies, School of Medicine, Tehran University of Medical Sciences, PO Box 13145-784, Tehran, Iran.
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Placenza FM, Fletcher PJ, Vaccarino FJ, Erb S. Effects of central neurokinin-1 receptor antagonism on cocaine- and opiate-induced locomotor activity and self-administration behaviour in rats. Pharmacol Biochem Behav 2006; 84:94-101. [PMID: 16757018 DOI: 10.1016/j.pbb.2006.04.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2005] [Revised: 04/04/2006] [Accepted: 04/11/2006] [Indexed: 11/28/2022]
Abstract
The neuropeptide substance P (SP) and its preferred receptor, the neurokinin-1 (NK-1) receptor, have been implicated in some of the reward-related behavioural effects of abused drugs, including psychostimulants and opiates. The first objective of the present series of experiments was to assess the role of the NK-1 receptor in two reward-related behavioural effects of cocaine: locomotor activity and self-administration. In tests for locomotor activity, rats were given intracerebroventricular (ICV) infusions of the selective NK-1 receptor antagonist, GR82334 (0, 10, 50 pmol), prior to systemic injections of cocaine. In self-administration experiments, rats were trained to self-administer cocaine on a fixed-ratio 5 (FR5) schedule of reinforcement. Following acquisition of stable responding, animals were pretreated with GR82334 (0, 2, 10, 50 pmol; ICV) prior to subsequent self-administration sessions. Based on evidence suggesting a potentially selective role for NK-1 receptors in opiate reward, we also examined the effects of GR82334 on morphine-induced locomotor activity and heroin self-administration. Results showed that GR82334 had no effect on cocaine-induced locomotor activity or cocaine self-administration, but attenuated morphine-induced locomotor activity and increased heroin self-administration. These findings suggest that endogenous activity at NK-1 receptors may play a specific role in opiate-induced, but not cocaine-induced, locomotor activation and reinforcement.
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Affiliation(s)
- Franca M Placenza
- Department of Psychology, University of Toronto, 100 St. George Street, Toronto, Ontario, Canada M5S 3G3.
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Placenza FM, Vaccarino FJ, Fletcher PJ, Erb S. Activation of central neurokinin-1 receptors induces reinstatement of cocaine-seeking behavior. Neurosci Lett 2005; 390:42-7. [PMID: 16125318 DOI: 10.1016/j.neulet.2005.07.050] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 07/22/2005] [Accepted: 07/29/2005] [Indexed: 11/16/2022]
Abstract
A number of neurochemical systems have been implicated in mediating relapse to drug-seeking behavior. Substance P (SP) is a neuropeptide that interacts with some of these systems, suggesting a possible role for SP and its preferred receptor, the neurokinin-1 (NK-1) receptor, in the mediation of relapse. In this study, we examined whether selective activation of NK-1 receptors induces reinstatement of cocaine-seeking behavior, and whether endogenous activity at these receptors is involved in mediating cocaine-induced reinstatement. For each experiment, rats were trained to self-administer cocaine for 8--10 days, and following a period of extinction, tests for reinstatement were given. To examine the effects of NK-1 receptor activation on reinstatement of cocaine-seeking behavior, animals received an intracerebroventricular (ICV) infusion of the selective NK-1 receptor agonist, [Sar(9)Met(O(2))(11)]-SP (0, 1, 3 microg), immediately prior to the test session. To examine the role of endogenous NK-1 receptor activity on cocaine-induced reinstatement, rats were pretreated with ICV infusions of the selective NK-1 receptor antagonists, RP 67580 (0, 0.1, 0.5, 2.5 nmol) or GR 82334 (0, 2, 10, 50 pmol), prior to systemic priming injections of cocaine (10mg/kg or 20mg/kg; i.p.). The results showed that [Sar(9)Met(O(2))(11)]-SP induced reinstatement of cocaine-seeking behavior, but that RP 67580 and GR 82334 had no effect on cocaine-induced reinstatement. These findings suggest that while activation of NK-1 receptors is capable of inducing reinstatement of cocaine-seeking behavior, endogenous activity at these receptors is not involved in mediating the priming effects of cocaine on reinstatement of drug-seeking behavior.
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Affiliation(s)
- Franca M Placenza
- Department of Psychology, University of Toronto, Toronto, Ont., Canada M5S 3G3
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Tsitolovsky LE. Protection from neuronal damage evoked by a motivational excitation is a driving force of intentional actions. ACTA ACUST UNITED AC 2005; 49:566-94. [PMID: 16269320 DOI: 10.1016/j.brainresrev.2005.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2004] [Revised: 12/16/2004] [Accepted: 02/25/2005] [Indexed: 01/13/2023]
Abstract
Motivation may be understood as an organism's subjective attitude to its current physiological state, which somehow modulates generation of actions until the organism attains an optimal state. How does this subjective attitude arise and how does it modulate generation of actions? Diverse lines of evidence suggest that elemental motivational states (hunger, thirst, fear, drug-dependence, etc.) arise as the result of metabolic disturbances and are related to transient injury, while rewards (food, water, avoidance, drugs, etc.) are associated with the recovery of specific neurons. Just as motivation and the very life of an organism depend on homeostasis, i.e., maintenance of optimum performance, so a neuron's behavior depends on neuronal (i.e., ion) homeostasis. During motivational excitation, the conventional properties of a neuron, such as maintenance of membrane potential and spike generation, are disturbed. Instrumental actions may originate as a consequence of the compensational recovery of neuronal excitability after the excitotoxic damage induced by a motivation. When the extent of neuronal actions is proportional to a metabolic disturbance, the neuron theoretically may choose a beneficial behavior even, if at each instant, it acts by chance. Homeostasis supposedly may be directed to anticipating compensation of the factors that lead to a disturbance of the homeostasis and, as a result, participates in the plasticity of motivational behavior. Following this line of thought, I suggest that voluntary actions arise from the interaction between endogenous compensational mechanisms and excitotoxic damage of specific neurons, and thus anticipate the exogenous compensation evoked by a reward.
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Affiliation(s)
- Lev E Tsitolovsky
- Department of Life Science, Bar-Ilan University, Ramat-Gan 52900, Israel.
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Macedo CE, Martinez RCR, de Souza Silva MA, Brandão ML. Increases in extracellular levels of 5-HT and dopamine in the basolateral, but not in the central, nucleus of amygdala induced by aversive stimulation of the inferior colliculus. Eur J Neurosci 2005; 21:1131-8. [PMID: 15787718 DOI: 10.1111/j.1460-9568.2005.03939.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Consistent evidence has shown that dopamine release in the prefrontal cortex is increased by electrical stimulation of the inferior colliculus (IC) as unconditioned stimulus. Recent reports have also demonstrated that inactivation of the basolateral nucleus of the amygdala (BLA) with muscimol enhances the behavioural consequences of the aversive stimulation of the IC and reduces the dopamine release in the prefrontal cortex. Moreover, neurotoxic lesions of the BLA enhance whereas those of the central nucleus of the amygdala (CeA) reduce the aversiveness of the electrical stimulation of the IC. Based on these findings the present study examined the effects of the electrical stimulation of the IC on the extracellular levels of serotonin and dopamine in the BLA and CeA. To this end, rats implanted with a stimulation electrode in the IC also bore a microdialysis probe in the BLA or CeA for determination of the release of dopamine and serotonin. IC electrical stimulation at the freezing and escape thresholds increased the levels of serotonin ( approximately 70%) and dopamine ( approximately 60%) in the BLA related to the basal values. Similarly, the metabolites DOPAC and 5-HIAA increased in a parallel fashion in BLA. No significant changes could be detected in these biogenic amines and metabolites in CeA following IC aversive stimulation. These findings point to a differential role of serotonergic and dopaminergic mechanisms of the BLA and CeA in the setting up of adaptive responses to fear states generated at the inferior colliculus level.
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Affiliation(s)
- Carlos Eduardo Macedo
- Laboratório de Psicobiologia, Faculdade Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo (USP) 14040-901, Ribeirão Preto, SP Brazil
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Nikolaev SV, Lebedev AA, Bychkov ER, Oblyapin AV, Dambinova SA, Shabanov PD. The effects of substance P after central administration on the activity of the mesolimbic system of the rat brain as studied by microdialysis. ACTA ACUST UNITED AC 2005; 34:743-6. [PMID: 15526431 DOI: 10.1023/b:neab.0000036016.65208.27] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
In vivo microdialysis was used to study the effects of substance P on dopamine, dihydroxyphenylacetic acid, and homovanillic acid levels in the nucleus accumbens in rats. Each animal received sequential injections of physiological saline, 0.1 microg of substance P, and 1 microg of substance P into the lateral ventricle over three days. Dialysates showed increases in dopamine levels in response to neuropeptide, by 41% for the 0.1 microg dose and 71% for the 1 microg dose. The dynamics of these changes also depended on the concentration of the agent. Administration of 1 microg of substance P gave a peak dopamine level at 50 min; the neurotransmitter level remained significantly elevated 75 min after dosage with substance P. The dopamine level was increased only at 75 min when the 0.1 microg dose of neuropeptide was used. Changes in metabolite levels were also dose-dependent. After the 1 microg dose, the dihydroxyphenylacetic acid level increased by 28%, while the 0.1 microg dose produced no significant change in the level of this metabolite. The homovanillic acid level did not respond to administration of substance P at either dose. These data support the suggestion that the influence of substance P on the internal compensation system is to a significant extent mediated by dopaminergic mechanisms and provides a possible explanation for the effects of the neuropeptide seen in a conditioned place preference reflex.
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Affiliation(s)
- S V Nikolaev
- Institute of the Human Brain, Russian Academy of Sciences, 12a Academician Pavlov Street, 197376 St. Petersburg, Russia
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Müller CP, Thönnessen H, De Souza Silva MA, Fink H, Bert B, Carey RJ, Huston JP. Nucleus accumbens serotonin1A receptors control cocaine-induced hyperactivity but not local serotonin increase: an in vivo microdialysis study. Neuropharmacology 2004; 47:205-15. [PMID: 15223299 DOI: 10.1016/j.neuropharm.2004.03.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2003] [Revised: 03/18/2004] [Accepted: 03/29/2004] [Indexed: 10/26/2022]
Abstract
The nucleus accumbens (Nac) is an important structure for cocaine-induced hyperactivity and receives a dense serotonergic (5-HT) innervation. Previous studies showed that a systemic activation of 5-HT(1A) receptors potentiates cocaine-induced hyperlocomotion, but attenuates the cocaine-induced 5-HT increase in the Nac. In order to address the role of Nac 5-HT(1A) receptors in the control of cocaine-induced and spontaneous behavioural activity and local 5-HT release, we used in vivo microdialysis in freely moving rats. The 5-HT(1A)-receptor agonist, 8-OH-DPAT (0, 1 and 10 microM), was applied locally into the Nac by reverse dialysis followed by a cocaine (10 mg/kg) or saline i.p. injection. The Nac 5-HT(1A)-receptor activation potentiated cocaine-induced hyperlocomotion, but attenuated rearing behaviour dose-dependently. Parallel to that, the cocaine-induced increase in Nac 5-HT dialysate level was unaffected, as were the decreases in 5-HIAA and DOPAC dialysate levels after cocaine. In saline treated rats, the local application of 8-OH-DPAT into the Nac affected neither spontaneous behavioural activity nor 5-HT, 5-HIAA or DOPAC dialysate levels in the Nac. These data suggest that Nac 5-HT(1A) receptors exert a bi-directional control of cocaine-induced hyperactivity, while not affecting spontaneous behaviour. Furthermore, accumbal 5-HT(1A) receptors do not appear to be directly involved in the acute effects of cocaine on 5-HT, 5-HIAA or DOPAC levels in the Nac.
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Affiliation(s)
- C P Müller
- Institute of Physiological Psychology I, Center for Biological and Medical Research, University of Düsseldorf, Universitätsstr. 1, 40225 Duesseldorf, Germany
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Nikolaev SV, Bychkov ER, Lebedev AA, Dambinova SA. Mechanisms of the influences of the central administration of substance P on ethanol consumption in chronically alcoholic rats. ACTA ACUST UNITED AC 2004; 33:905-9. [PMID: 14969430 DOI: 10.1023/a:1025905023554] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The effects of central administration of substance P (SP) on alcohol consumption and dopamine metabolism in the projections of the mesocorticolimbic and nigrostriatal systems of the brain were studied in chronically alcoholic rats. Rats received 15% ethanol solution for 6 months without choice. Intraventricular administration of SP (1 microg/rat) decreased consumption of 10% ethanol solution by 41% compared with controls in an alcohol free choice test lasting one day. After chronic alcoholism, there was a decrease in the ratio of dihydroxyphenylacetic acid (DOPA) and homovanillic acid (HVA) to dopamine in the nucleus accumbens and striatum in rats subjected to alcoholism, as compared with intact controls. Chronically alcoholic rats treated with SP showed increases in DOPA, HVA, and the DOPA:dopamine and HVA:dopamine ratios in the nucleus accumbens as compared with animals given physiological saline, by 17%, 23%, 9% and 19% respectively. The only increases in the striatum were in the absolute levels of DOPA and HVA, by 28% and 29%, while the ratios of these metabolites to dopamine remained unchanged. Thus, central administration of SP decreased the voluntary consumption of ethanol in the ethanol free choice test and enhanced dopamine metabolism in structures of the mesolimbic and nigrostriatal systems in chronically alcoholic rats.
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Affiliation(s)
- S V Nikolaev
- Institute of the Human Brain, Russian Academy of Sciences, 12a Academician Pavlov Street, 197376 St. Petersburg, Russia
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Müller CP, Thönnessen H, Barros M, Tomaz C, Carey RJ, Huston JP. Hippocampus 5-HT1A-receptors attenuate cocaine-induced hyperlocomotion and the increase in hippocampal but not nucleus accumbens 5-HT. Hippocampus 2004; 14:710-21. [PMID: 15318330 DOI: 10.1002/hipo.10209] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cocaine induces an increase in hippocampal and nucleus accumbens (Nac) serotonin (5-HT) concentration parallel to locomotor activation. Both effects can be modulated by systemic 5-HT(1A)-receptor agonism/antagonism. Given the contribution of the hippocampus to spontaneous behavioral activity, these observations suggest a role for hippocampal 5-HT as well in the modulation of cocaine effects on behavior. To determine the role of hippocampal 5-HT(1A)-receptors in cocaine effects on behavior and hippocampal 5-HT release, we used in vivo microdialysis in freely moving rats. The 5-HT(1A)-receptor agonist, 8-OH-DPAT (0, 0.1, 1 and 10 microM), was applied locally into the hippocampus by reversed dialysis followed by a cocaine (10 mg/kg) or saline i.p. injection. The hippocampal 5-HT(1A)-receptor activation attenuated cocaine-induced hyperlocomotion and rearing behavior dose-dependently. Parallel to that, the cocaine-induced 5-HT increase was attenuated dose-dependently in the hippocampus but was left unaffected in the Nac. The intra-hippocampal application of 8-OH-DPAT affected neither behavioral activity nor 5-HT concentration in the hippocampus and in the Nac. In accord with these findings, hippocampal 5-HT(1A)-receptors may not be directly involved in the regulation of spontaneous behavior or basal 5-HT concentration in the hippocampus and Nac. However, the results indicate an inhibitory role of hippocampal 5-HT(1A)-receptors in cocaine-induced hyperactivity and in the 5-HT increase evoked by cocaine in the hippocampus but not in the Nac.
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Affiliation(s)
- Christian P Müller
- Institute of Physiological Psychology I and Center for Biological and Medical Research, University of Düsseldorf, Düsseldorf, Germany
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40
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Neurokinin-1 receptor-expressing neurons in the amygdala modulate morphine reward and anxiety behaviors in the mouse. J Neurosci 2003. [PMID: 12967989 DOI: 10.1523/jneurosci.23-23-08271.2003] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mice lacking the neurokinin-1 (NK1) receptor, the preferred receptor for the neuropeptide substance P (SP), do not show many of the behaviors associated with morphine reward. To identify the areas of the brain that might contribute to this effect, we assessed the behavioral effects of ablation of neurons expressing the NK1 receptor in specific regions of the mouse brain using the neurotoxin substance P-saporin. In a preliminary investigation, bilateral ablation of these neurons from the amygdala, but not the nucleus accumbens and dorsomedial caudate putamen, brought about reductions in morphine reward behavior. Subsequently, the effect of ablation of these neurons in the amygdala on anxiety behavior was assessed using the elevated plus maze (EPM), before conditioned place preference (CPP), and locomotor responses to morphine were measured. Loss of NK1 receptor-expressing neurons in the amygdala caused an increase in anxiety-like behavior on the EPM. It also brought about a reduction in morphine CPP scores and the stimulant effect of acute morphine administration relative to saline controls, without affecting CPP to cocaine. NK1 receptor-expressing neurons in the mouse amygdala therefore modulate morphine reward behaviors. These observations mirror those observed in NK1 receptor knock-out (NK1-/-) mice and suggest that the amygdala is an important area for the effects of SP and the NK1 receptor in the motivational properties of opiates, as well as the control of behaviors related to anxiety.
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Müller CP, Carey RJ, Salloum JB, Huston JP. Serotonin1A-receptor agonism attenuates the cocaine-induced increase in serotonin levels in the hippocampus and nucleus accumbens but potentiates hyperlocomotion: an in vivo microdialysis study. Neuropharmacology 2003; 44:592-603. [PMID: 12668045 DOI: 10.1016/s0028-3908(03)00046-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The hippocampus and the nucleus accumbens (Nac) are important structures for the modulation of spontaneous locomotor activity. Both structures receive a serotonergic (5-HT) innervation. We have previously reported that the 5-HT(1A)-receptor antagonist WAY 100635 blocked cocaine-induced hyperactivity, while potentiating cocaine-induced 5-HT increases in the hippocampus and the Nac. In order to further investigate the relationship between extracellular 5-HT concentration and cocaine-induced behaviour, we used in vivo microdialysis to measure the effects of the 5-HT(1A)-receptor agonist 8-OH-DPAT on cocaine-induced changes in the extracellular 5-HT concentration in the hippocampus and the Nac and on behavioural activity. Following a pilot pretest in which we determined the lowest effective dose of 8-OH-DPAT for potentiating cocaine-induced hyperlocomotion, four groups of rats were given one of the following drug treatments: 8-OH-DPAT (0.2 mg/kg) and cocaine (10 mg/kg), saline and cocaine (10 mg/kg), 8-OH-DPAT (0.2 mg/kg) and saline, or saline and saline. The injections were administered i.p. and spaced 30 min apart. We found that the 5-HT(1A)-receptor agonist 8-OH-DPAT attenuated the cocaine-induced increases in 5-HT in the hippocampus and the Nac, but potentiated cocaine-induced hyperlocomotion. 5-HT metabolite measurements revealed a complex role for the 5-HT(1A)-receptor in the broad spectrum of cocaine's neurochemical effects. Altogether, these observations support an important role of the 5-HT(1A)-receptor in the hippocampus and Nac in the modulation of cocaine stimulant effects.
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Affiliation(s)
- C P Müller
- Institute of Physiological Psychology I, Center for Biological and Medical Research, University of Düsseldorf, Universitätsstr. 1, Germany
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42
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Bellemère G, Morain P, Vaudry H, Jégou S. Effect of S 17092, a novel prolyl endopeptidase inhibitor, on substance P and alpha-melanocyte-stimulating hormone breakdown in the rat brain. J Neurochem 2003; 84:919-29. [PMID: 12603817 DOI: 10.1046/j.1471-4159.2003.01536.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In the present study, we have investigated the effects of a novel prolyl endopeptidase (EC 3.4.21.26, PEP) inhibitor, compound S 17092, on substance P (SP) and alpha-melanocyte-stimulating hormone (alpha-MSH) metabolism in the rat brain. In vitro experiments revealed that S 17092 inhibits in a dose-dependent manner PEP activity in rat cortical extracts (IC50 = 8.3 nm). In addition, S 17092 totally abolished the degradation of SP and alpha-MSH induced by bacterial PEP. In vivo, a significant decrease in PEP activity was observed in the medulla oblongata after a single oral administration of S 17092 at doses of 10 and 30 mg/kg (-78% and -82%, respectively) and after chronic oral treatment with S 17092 at doses of 10 and 30 mg/kg per day (-75% and -88%, respectively). Concurrently, a single administration of S 17092 (30 mg/kg) caused a significant increase in SP- and alpha-MSH-like immunoreactivity (LI) in the frontal cortex (+41% and +122%, respectively) and hypothalamus (+84% and +49%, respectively). In contrast, chronic treatment with S 17092 did not significantly modify SP- and alpha-MSH-LI in the frontal cortex and hypothalamus. Collectively, the present results show that S 17092 elevates SP and alpha-MSH concentrations in the rat brain by inhibiting PEP activity. These data suggest that the effect of S 17092 on memory impairment can be accounted for, at least in part, by inhibition of catabolism of promnesic neuropeptides such as SP and alpha-MSH.
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Affiliation(s)
- Gaëlle Bellemère
- European Institute for Peptide Research (IFRMP23), Laboratory of Cellular and Molecular Neuroendocrinology, INSERM U 413, CNRS, University of Rouen, 76821 Mont-Saint-Aignan, France
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Lénárd L, Kertes E. Influence of passive avoidance learning by substance P in the basolateral amygdala. ACTA BIOLOGICA HUNGARICA 2002; 53:95-104. [PMID: 12064784 DOI: 10.1556/abiol.53.2002.1-2.11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neuropeptide substance P (SP) has reinforcing and memory facilitating effects after its peripheral or central application. Rats self-inject SP into the ventromedial caudate-putamen and SP microinjections into the basal forebrain induce place preference with a simultaneous increase of dopamine level. In the amygdaloid body SP positive neurones and terminals have been identified. The aim of the present study was to examine the possible reinforcing effects of SP in the basolateral amygdala (ABL). CFY male rats were conditioned in two-compartment passive avoidance paradigm and place preference was examined in two-compartment-box and in circular open field. Animals were microinjected bilaterally with 10 ng SP, 100 ng SP or vehicle solution (0.4 microl/side) into the ABL. Results showed that post-shock infusion of 10 ng SP significantly enhanced passive avoidance learning while 100 ng SP was ineffective. In two-compartment-box and in circular open field place preference did not develop after SP treatments, however. Our data are the first to demonstrate that SP in the ABL is involved in learning and memory processes related to aversive situations. Results that SP microinjections were not followed by rewarding-reinforcing consequences in place preference paradigms indicate that the local SP network in the ABL is not involved in neuronal circuitry responsible for addictive behaviour.
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Affiliation(s)
- L Lénárd
- Neurophysiology Research Group of the Hungarian Academy of Sciences at Institute of Physiology, Pécs University Medical School.
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Müller CP, De Souza Silva MA, DePalma G, Tomaz C, Carey RJ, Huston JP. The selective serotonin(1A)-receptor antagonist WAY 100635 blocks behavioral stimulating effects of cocaine but not ventral striatal dopamine increase. Behav Brain Res 2002; 134:337-46. [PMID: 12191821 DOI: 10.1016/s0166-4328(02)00042-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An increase in the extracellular dopamine (DA) concentration is generally accepted as an important neurochemical mediator of the behavioral effects of cocaine. Cocaine induced increases in serotonergic (5-HT) activity also appears to be involved in these effects. Here we describe the effects of the 5-HT(1A)-receptor antagonist WAY 100635 on the behavioral and neurochemical effects of cocaine. In-vivo microdialysis was used in behaving rats to measure extracellular concentration of DA in the nucleus accumbens (Nac). Four groups of animals received one of the following drug combinations: WAY 100635 (0.4 mg/kg) and cocaine (10 mg/kg), saline and cocaine (10 mg/kg), WAY 100635 (0.4 mg/kg) and saline, or saline and saline. The injections were administered i.p. and spaced 20 min apart. The pretreatment with WAY 100635 significantly attenuated the locomotor stimulant effects of cocaine without altering the DA overflow in the Nac. WAY 100635 itself did not modify locomotion or the extracellular DA concentration in the Nac. These results indicate that (1) the 5-HT(1A)-receptor is an important component in the mediation of cocaine locomotor stimulant effects, and (2) an increase in the extracellular DA concentration in the Nac might be a necessary but is not a sufficient condition for the locomotor stimulant effects of cocaine.
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Affiliation(s)
- Christian P Müller
- Institute of Physiological Psychology I and Center for Biological and Medical Research, University of Düsseldorf, Universitätsstr 1, 40225 Düsseldorf, Germany
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Müller CP, Carey RJ, De Souza Silva MA, Jocham G, Huston JP. Cocaine increases serotonergic activity in the hippocampus and nucleus accumbens in vivo: 5-HT1a-receptor antagonism blocks behavioral but potentiates serotonergic activation. Synapse 2002; 45:67-77. [PMID: 12112399 DOI: 10.1002/syn.10083] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The hippocampus is an important mediator of learning and reinforcement, but its role in cocaine effects has received little attention. Neuronal activity in the hippocampus and the nucleus accumbens (Nac) depend on serotonergic (5-HT) transmission. Here we describe for the first time a cocaine-induced increase in 5-HT concentration in the hippocampus and the Nac parallel to behavioral activation. In addition, pretreatment with the 5-HT(1A)-receptor antagonist WAY 100635 blocked the behavioral activation after cocaine while potentiating the 5-HT increase in the hippocampus and the Nac. In vivo microdialysis was used in behaving rats to measure extracellular concentration of 5-HT in the hippocampus and the Nac. Four groups of animals received one of the following drug combinations: WAY 100635 (0.4 mg/kg) and cocaine (10 mg/kg), saline and cocaine (10 mg/kg), WAY 100635 (0.4 mg/kg) and saline, or saline and saline. The injections were administered i.p. and spaced 30 min apart. It was found that 1.) cocaine, at a dose that activates behavior, increases 5-HT levels in the hippocampus and in the Nac, and 2.) 5-HT(1A)-receptor antagonism can cause a dissociation of the hippocampal and Nac 5-HT activity from behavioral activation after cocaine. These results are discussed within the framework of the hippocampal-accumbens projection and its contribution to behavioral activity. They suggest that the hippocampus may have a role in mediating the behavioral and neurochemical effects of cocaine.
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Affiliation(s)
- Christian P Müller
- Institute of Physiological Psychology I and Center for Biological and Medical Research, University of Düsseldorf, 40225 Düsseldorf, Germany.
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46
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Bast T, Diekamp B, Thiel C, Schwarting RKW, Güntürkün O. Functional aspects of dopamine metabolism in the putative prefrontal cortex analogue and striatum of pigeons (Columba livia). J Comp Neurol 2002; 446:58-67. [PMID: 11920720 DOI: 10.1002/cne.10187] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Dopamine (DA) in mammalian associative structures, such as the prefrontal cortex (PFC), plays a prominent role in learning and memory processes, and its homeostasis differs from that of DA in the striatum, a sensorimotor region. The neostriatum caudolaterale (NCL) of birds resembles the mammalian PFC according to connectional, electrophysiological, and behavioral data. In the present study, DA regulation in the associative NCL and the striatal lobus parolfactorius (LPO) of pigeons was compared to uncover possible differences corresponding to those between mammalian PFC and striatum. Extracellular levels of DA and its metabolites (homovanillic acid [HVA], dihydroxyphenylacetic acid [DOPAC]) and the serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) were investigated by in vivo microdialysis of urethane-anesthetized pigeons under basal conditions and after systemic administration of D-amphetamine. DA was reliably determined only in LPO dialysates, and DA metabolite levels were significantly higher in LPO than in NCL. The HVA/DOPAC ratio, indicating extracellular lifetime of DA, was more than twice as high in NCL than in LPO dialysates. After amphetamine, DA increased in LPO while still being undetectable in NCL, and DA metabolites decreased in both regions. 5-HIAA slightly decreased in NCL dialysates. Amphetamine effects were delayed in NCL compared with the striatum. In conclusion, effects of amphetamine on the pigeon's ascending monoamine systems resemble those found in mammals, suggesting similar regulatory properties. The neurochemical differences between NCL and LPO parallel those between associative regions, such as PFC and dorsal striatum in mammals. They may reflect weaker regulation of extracellular DA, favoring DAergic volume transmission, in associative than striatal forebrain regions.
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Affiliation(s)
- Tobias Bast
- Biopsychologie, Fakultät für Psychologie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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Galosi R, Lenard L, Knoche A, Haas H, Huston JP, Schwarting RK. Dopaminergic effects of histamine administration in the nucleus accumbens and the impact of H1-receptor blockade. Neuropharmacology 2001; 40:624-33. [PMID: 11249972 DOI: 10.1016/s0028-3908(00)00181-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The mesolimbic dopamine system is thought to play a critical role in reward-related processes. A number of studies have shown that lesion or inhibition of histaminergic neurons acting through H1 receptors can potentiate the effects of drug-induced reward (e.g., psychostimulants and opioids) and can enhance the reinforcing effects of electrical stimulation of the brain. Since dopamine transmission in the nucleus accumbens is thought to provide a crucial link in these histaminergic actions, we examined the effects of local histamine application (0.1, 1.0 and 10.0 micromol/l) on dopamine and its metabolites in the nucleus accumbens of anesthetized rats by means of unilateral reverse dialysis. To study the influence of H1 receptors, we also applied the H1-receptor antagonist pyrilamine (10.0 and 20.0 mg/kg, intraperitoneally) 20 min before histamine administration (1 mmol/l). Finally, pyrilamine (0.1, 1.0 and 10.0 micromol/l) was locally administered into the nucleus accumbens. The data show that histamine can enhance extracellular dopamine levels in the nucleus accumbens in a dose-dependent way. This increase was partially antagonized by prior peripheral administration of 10 mg/kg, and was completely blocked by 20 mg/kg, of pyrilamine. Finally, intra-accumbens administration of pyrilamine locally decreased dopamine and increased dihydroxyphenylacetic acid and homovanillic acid levels. These data are discussed with respect to the possible interactions between dopaminergic and histaminergic mechanisms in the mesolimbic system and their relation to mechanisms of reinforcement.
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Affiliation(s)
- R Galosi
- Institute of Physiology and Neurophysiology Research Group of Hungarian Academy of Sciences, Pecs University Medical School, Pecs, Hungary
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De Souza Silva MA, Hasenöhrl RU, Tomaz C, Schwarting RK, Huston JP. Differential modulation of frontal cortex acetylcholine by injection of substance P into the nucleus basalis magnocellularis region in the freely-moving vs. the anesthetized preparation. Synapse 2000; 38:243-53. [PMID: 11020227 DOI: 10.1002/1098-2396(20001201)38:3<243::aid-syn3>3.0.co;2-g] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In vivo microdialysis was used to assess the effects of unilateral substance P (SP) injection into the nucleus basalis magnocellularis on extracellular levels of acetylcholine (ACh) in the frontal cortex, either in freely moving or urethane-anesthetized rats. The results show that the neurochemical effects of SP are critically dependent on the choice of the experimental preparation: In the freely-moving rat, the injection procedure led to behavioral and concurrent bilateral cholinergic activation in the frontal cortex. This cholinergic activation was ipsilaterally reduced by intrabasalis injection of SP (1 ng), indicating that the peptide exerted an inhibitory influence on the neurochemical effect exerted by handling, intracranial needle insertion, and vehicle injection. In the anesthetized preparation, SP had a biphasic dose-dependent action on cortical ACh: a short-lasting ipsilateral increase immediately after injection (especially with 1 ng), and a delayed bilateral increase after more than 2 h (10, 100 ng). The procedure of inserting the injection needle moderately increased cortical ACh levels. Methodologically, these data are discussed with respect to the importance of using anesthetized vs. freely moving rats and the effects of intraparenchymal injections.
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Affiliation(s)
- M A De Souza Silva
- Institute of Physiological Psychology I, University of Düsseldorf, Düsseldorf, Germany
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49
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Abstract
The present article reviews the studies so far published on the psychopharmacological effects mediated by tachykinin NK-3 receptors in laboratory animals. Central administration of NK-3 receptor agonists has been reported to attenuate alcohol intake in alcohol-preferring rats and to evoke conditioned place preference. These findings suggest that NK-3 receptors may affect reward processes to drugs of abuse. Anxiolytic-like and antidepressant-like effects have been previously reported for NK-1 receptor antagonists, and anxiolytic-like effects for NK-2 receptor antagonists. More recently, it has been shown that NK-3 receptor agonists have anxiolytic-like and antidepressant-like effects in mice and rats, while an NK-3 receptor antagonist was reported to be anxiogenic in mice. These findings indicate that different TK receptor subtypes may be involved in anxiolytic-like and antidepressant-like effects in laboratory animals and raise interest for the possible role of NK-3 receptors in the control of anxiety and depression in man.
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Affiliation(s)
- M Massi
- Department of Pharmacological Sciences and Experimental Medicine, University of Camerino, 62032, Camerino, Italy.
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Hasenöhrl RU, Souza-Silva MA, Nikolaus S, Tomaz C, Brandao ML, Schwarting RK, Huston JP. Substance P and its role in neural mechanisms governing learning, anxiety and functional recovery. Neuropeptides 2000; 34:272-80. [PMID: 11049731 DOI: 10.1054/npep.2000.0824] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The neurokinin Substance P (SP) is widely distributed in the central nervous system and has been extensively studied in various functional aspects. This review focuses on the behavioral relevance of SP. Here we show that SP can have memory-promoting, reinforcing and anxiolytic-like effects when administered systemically or into the nucleus basalis of the ventral pallidum. These effects seem to be mediated via the SP-preferring NK(1)receptor and differentially related to N- versus C-terminal fragments of the undecapeptide. Secondly, SP injection into the ventral pallidum can lead to increases of acetylcholine in frontal cortex and dopamine in nucleus accumbens, suggesting that the hypermnestic, positively reinforcing and anxiolytic effects observed upon basal forebrain injection of SP are mediated by activation of the nucleus accumbens-ventral pallidum circuitry. Furthermore, SP and certain SP-fragments may not only be considered to have beneficial behavioral effects in normal animals, but can also prevent lesion-induced functional deficits and improve the speed of recovery. This indicates that SP agonists might also have a neuroprotective capacity in parallel with recovery-promoting actions.
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Affiliation(s)
- R U Hasenöhrl
- Institute of Physiological Psychology & Center for Biological and Medical Research, University of Düsseldorf, Düsseldorf, Germany
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