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Levine AS, Jewett DC, Kotz CM, Olszewski PK. Behavioral plasticity: Role of neuropeptides in shaping feeding responses. Appetite 2022; 174:106031. [PMID: 35395362 DOI: 10.1016/j.appet.2022.106031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 03/12/2022] [Accepted: 03/29/2022] [Indexed: 11/28/2022]
Abstract
Behavioral plasticity refers to changes occurring due to external influences on an organism, including adaptation, learning, memory and enduring influences from early life experience. There are 2 types of behavioral plasticity: "developmental", which refers to gene/environment interactions affecting a phenotype, and "activational" which refers to innate physiology and can involve structural physiological changes of the body. In this review, we focus on feeding behavior, and studies involving neuropeptides that influence behavioral plasticity - primarily opioids, orexin, neuropeptide Y, and oxytocin. In each section of the review, we include examples of behavioral plasticity as it relates to actions of these neuropeptides. It can be concluded from this review that eating behavior is influenced by a number of external factors, including time of day, type of food available, energy balance state, and stressors. The reviewed work underscores that environmental factors play a critical role in feeding behavior and energy balance, but changes in eating behavior also result from a multitude of non-environmental factors, such that there can be no single mechanism or variable that can explain ingestive behavior.
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Affiliation(s)
- Allen S Levine
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, 55113, USA.
| | - David C Jewett
- Department of Psychology, University of Wisconsin-Eau Claire, Eau Claire, WI, USA
| | - Catherine M Kotz
- Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, MN, 55414, USA; Geriatric, Research, Education and Clinical Center, Minneapolis Veterans Affairs Health, Minneapolis, MN, 55417, USA
| | - Pawel K Olszewski
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, MN, 55113, USA; Department of Integrative Biology and Physiology, Medical School, University of Minnesota, Minneapolis, MN, 55414, USA; Faculty of Science and Engineering, University of Waikato, Hamilton, 3240, New Zealand
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Cowan A, Liu-Chen LY, Inan S. Itching-like behavior: A common effect of the kappa opioid receptor antagonist 5′-guanidinonaltrindole and the biased kappa opioid receptor agonist 6′-guanidinonaltrindole in mice. MEDICINE IN DRUG DISCOVERY 2021. [DOI: 10.1016/j.medidd.2021.100097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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Bodnar RJ. Endogenous opioid modulation of food intake and body weight: Implications for opioid influences upon motivation and addiction. Peptides 2019; 116:42-62. [PMID: 31047940 DOI: 10.1016/j.peptides.2019.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 03/04/2019] [Accepted: 04/08/2019] [Indexed: 12/12/2022]
Abstract
This review is part of a special issue dedicated to Opioid addiction, and examines the influential role of opioid peptides, opioid receptors and opiate drugs in mediating food intake and body weight control in rodents. This review postulates that opioid mediation of food intake was an example of "positive addictive" properties that provide motivational drives to maintain opioid-seeking behavior and that are not subject to the "negative addictive" properties associated with tolerance, dependence and withdrawal. Data demonstrate that opiate and opioid peptide agonists stimulate food intake through homeostatic activation of sensory, metabolic and energy-related In contrast, general, and particularly mu-selective, opioid receptor antagonists typically block these homeostatically-driven ingestive behaviors. Intake of palatable and hedonic food stimuli is inhibited by general, and particularly mu-selective, opioid receptor antagonists. The selectivity of specific opioid agonists to elicit food intake was confirmed through the use of opioid receptor antagonists and molecular knockdown (antisense) techniques incapacitating specific exons of opioid receptor genes. Further extensive evidence demonstrated that homeostatic and hedonic ingestive situations correspondingly altered the levels and expression of opioid peptides and opioid receptors. Opioid mediation of food intake was controlled by a distributed brain network intimately related to both the appetitive-consummatory sites implicated in food intake as well as sites intimately involved in reward and reinforcement. This emergent system appears to sustain the "positive addictive" properties providing motivational drives to maintain opioid-seeking behavior.
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology, Queens College, City University of New York, United States; Psychology Doctoral Program and CUNY Neuroscience Collaborative, The Graduate Center of the City University of New York, United States.
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Kappa Opioid Receptor Agonist Mesyl Sal B Attenuates Behavioral Sensitization to Cocaine with Fewer Aversive Side-Effects than Salvinorin A in Rodents. Molecules 2018; 23:molecules23102602. [PMID: 30314288 PMCID: PMC6222496 DOI: 10.3390/molecules23102602] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 10/02/2018] [Accepted: 10/09/2018] [Indexed: 01/02/2023] Open
Abstract
The acute activation of kappa opioid receptors (KOPr) produces antinociceptive and anti-cocaine effects, however, their side-effects have limited further clinical development. Mesyl Sal B is a potent and selective KOPr analogue of Salvinorin A (Sal A), a psychoactive natural product isolated from the plant Salvia divinorum. We assessed the antinociceptive, anti-cocaine, and side-effects of Mesyl Sal B. The anti-cocaine effects are evaluated in cocaine-induced hyperactivity and behavioral sensitization to cocaine in male Sprague Dawley rats. Mesyl Sal B was assessed for anhedonia (conditioned taste aversion), aversion (conditioned place aversion), pro-depressive effects (forced swim test), anxiety (elevated plus maze) and learning and memory deficits (novel object recognition). In male B6.SJL mice, the antinociceptive effects were evaluated in warm-water (50 °C) tail withdrawal and intraplantar formaldehyde (2%) assays and the sedative effects measured with the rotarod performance task. Mesyl Sal B (0.3 mg/kg) attenuated cocaine-induced hyperactivity and behavioral sensitization to cocaine without modulating sucrose self-administration and without producing aversion, sedation, anxiety, or learning and memory impairment in rats. However, increased immobility was observed in the forced swim test indicating pro-depressive effects. Mesyl Sal B was not as potent as Sal A at reducing pain in the antinociceptive assays. In conclusion, Mesyl Sal B possesses anti-cocaine effects, is longer acting in vivo and has fewer side-effects when compared to Sal A, however, the antinociceptive effects are limited.
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D’Addario C, Palazzo MC, Benatti B, Grancini B, Pucci M, Di Francesco A, Camuri G, Galimberti D, Fenoglio C, Scarpini E, Altamura AC, Maccarrone M, Dell’Osso B. Regulation of gene transcription in bipolar disorders: Role of DNA methylation in the relationship between prodynorphin and brain derived neurotrophic factor. Prog Neuropsychopharmacol Biol Psychiatry 2018; 82:314-321. [PMID: 28830794 PMCID: PMC5859566 DOI: 10.1016/j.pnpbp.2017.08.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/04/2017] [Accepted: 08/13/2017] [Indexed: 10/19/2022]
Abstract
Bipolar Disorder (BD) is a prevalent and disabling condition, determined by gene-environment interactions, possibly mediated by epigenetic mechanisms. The present study aimed at investigating the transcriptional regulation of BD selected target genes by DNA methylation in peripheral blood mononuclear cells of patients with a DSM-5 diagnosis of type I (BD-I) and type II (BD-II) Bipolar Disorders (n=99), as well as of healthy controls (CT, n=42). The analysis of gene expression revealed prodynorphin (PDYN) mRNA levels significantly reduced in subjects with BD-II but not in those with BD-I, when compared to CT. Other target genes (i.e. catechol-O-methyltransferase (COMT), glutamate decarboxylase (GAD67), serotonin transporter (SERT) mRNA levels remained unaltered. Consistently, an increase in DNA methylation at PDYN gene promoter was observed in BD-II patients vs CT. After stratifying data on the basis of pharmacotherapy, patients on mood-stabilizers (i.e., lithium and anticonvulsants) were found to have lower DNA methylation at PDYN gene promoter. A significantly positive correlation in promoter DNA methylation was observed in all subjects between PDYN and brain derived neurotrophic factor (BDNF), whose methylation status had been previously found altered in BD. Moreover, among key genes relevant for DNA methylation establishment here analysed, an up-regulation of DNA Methyl Transferases 3b (DNMT3b) and of the methyl binding protein MeCP2 (methyl CpG binding protein 2) mRNA levels was also observed again just in BD-II subjects. A clear selective role of DNA methylation involvement in BD-II is shown here, further supporting a role for BDNF and its possible interaction with PDYN. These data might be relevant in the pathophysiology of BD, both in relation to BDNF and for the improvement of available treatments and development of novel ones that modulate epigenetic signatures.
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Affiliation(s)
- Claudio D’Addario
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Italy,Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden,Correspondence to: Claudio D’Addario, Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Teramo, Italy,
| | - Maria Carlotta Palazzo
- Centro Sant’Ambrogio Ordine Ospedaliero San Giovanni di Dio Fatebenefratelli, Milano, Italy
| | - Beatrice Benatti
- Department of Psychiatry, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - Benedetta Grancini
- Department of Psychiatry, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - Mariangela Pucci
- Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Italy
| | - Andrea Di Francesco
- Experimental Gerontology Section, Translational Gerontology Branch, National Institute on Aging, Baltimore, MD, USA
| | - Giulia Camuri
- Department of Psychiatry, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - Daniela Galimberti
- Department of Neurology, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - Chiara Fenoglio
- Department of Neurology, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - Elio Scarpini
- Department of Neurology, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - A. Carlo Altamura
- Department of Psychiatry, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy
| | - Mauro Maccarrone
- Department of Medicine, Campus Bio-Medico University of Rome, Rome, Italy,European Center for Brain Research, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Bernardo Dell’Osso
- Department of Psychiatry, Università degli Studi di Milano, Fondazione IRRCS Ca’ Granda, Ospedale Maggiore Policlinico, Milano, Italy,Department of Psychiatry and Behavioral Sciences, Bipolar Disorders Clinic, Stanford University, CA, USA,Correspondence to: Bernardo Dell’Osso, Department of Psychiatry, University of Milan, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Via Francesco Sforza 35, 20122 Milano, Italy,
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Karkhanis A, Holleran KM, Jones SR. Dynorphin/Kappa Opioid Receptor Signaling in Preclinical Models of Alcohol, Drug, and Food Addiction. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 136:53-88. [PMID: 29056156 DOI: 10.1016/bs.irn.2017.08.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The dynorphin/kappa opioid receptor (KOR) system is implicated in the "dark side" of addiction, in which stress exacerbates maladaptive responses to drug and alcohol exposure. For example, acute stress and acute ethanol exposure result in an elevation in dynorphin, the KOR endogenous ligand. Activation of KORs results in modulation of several neurotransmitters; however, this chapter will focus on its regulatory effects on dopamine in mesolimbic areas. Specifically, KOR activation has an inhibitory effect on dopamine release, thereby influencing reward processing. Repeated stimulation of KORs, for example, via chronic drug and/or stress exposure, results in increased function of the dynorphin/KOR system. This augmentation in KOR function shifts the homeostatic balance in favor of an overall reduction in dopamine signaling via either by reducing dopamine release or by increasing dopamine transporter function. This chapter examines the effects of chronic ethanol exposure on KOR function and the downstream effects on dopamine transmission. Additionally, the impact of chronic cocaine exposure and its effects on KOR function will be explored. Further, KORs may also be involved in driving excessive consumption of food, contributing to the risk of developing obesity. While some studies have shown that KOR agonists reduce drug intake, other studies have shown that antagonists reduce addiction-like behaviors, demonstrating therapeutic potential. For example, KOR inhibition reduces ethanol intake in dependent animals, motivation to self-administer cocaine in chronic stress-exposed animals, and food consumption in obese animals. This chapter will delve into the mechanisms by which modulation of the dynorphin/KOR system may be therapeutic.
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Affiliation(s)
| | | | - Sara R Jones
- Wake Forest School of Medicine, Winston-Salem, NC, United States.
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Central oxytocin receptor stimulation attenuates the orexigenic effects of butorphanol tartrate. Neuroreport 2016; 27:1012-7. [DOI: 10.1097/wnr.0000000000000647] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Munro TA, Huang XP, Inglese C, Perrone MG, Van't Veer A, Carroll FI, Béguin C, Carlezon WA, Colabufo NA, Cohen BM, Roth BL. Selective κ opioid antagonists nor-BNI, GNTI and JDTic have low affinities for non-opioid receptors and transporters. PLoS One 2013; 8:e70701. [PMID: 23976952 PMCID: PMC3747596 DOI: 10.1371/journal.pone.0070701] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 06/21/2013] [Indexed: 01/16/2023] Open
Abstract
Background Nor-BNI, GNTI and JDTic induce selective κ opioid antagonism that is delayed and extremely prolonged, but some other effects are of rapid onset and brief duration. The transient effects of these compounds differ, suggesting that some of them may be mediated by other targets. Results In binding assays, the three antagonists showed no detectable affinity (Ki≥10 µM) for most non-opioid receptors and transporters (26 of 43 tested). There was no non-opioid target for which all three compounds shared detectable affinity, or for which any two shared sub-micromolar affinity. All three compounds showed low nanomolar affinity for κ opioid receptors, with moderate selectivity over μ and δ (3 to 44-fold). Nor-BNI bound weakly to the α2C-adrenoceptor (Ki = 630 nM). GNTI enhanced calcium mobilization by noradrenaline at the α1A-adrenoceptor (EC50 = 41 nM), but did not activate the receptor, displace radioligands, or enhance PI hydrolysis. This suggests that it is a functionally-selective allosteric enhancer. GNTI was also a weak M1 receptor antagonist (KB = 3.7 µM). JDTic bound to the noradrenaline transporter (Ki = 54 nM), but only weakly inhibited transport (IC50 = 1.1 µM). JDTic also bound to the opioid-like receptor NOP (Ki = 12 nM), but gave little antagonism even at 30 µM. All three compounds exhibited rapid permeation and active efflux across Caco-2 cell monolayers. Conclusions Across 43 non-opioid CNS targets, only GNTI exhibited a potent functional effect (allosteric enhancement of α1A-adrenoceptors). This may contribute to GNTI's severe transient effects. Plasma concentrations of nor-BNI and GNTI may be high enough to affect some peripheral non-opioid targets. Nonetheless, κ opioid antagonism persists for weeks or months after these transient effects dissipate. With an adequate pre-administration interval, our results therefore strengthen the evidence that nor-BNI, GNTI and JDTic are highly selective κ opioid antagonists.
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MESH Headings
- Allosteric Regulation
- Biological Transport
- Caco-2 Cells
- Calcium/metabolism
- Guanidines/metabolism
- Guanidines/pharmacology
- Humans
- Kinetics
- Morphinans/metabolism
- Morphinans/pharmacology
- Naltrexone/analogs & derivatives
- Naltrexone/metabolism
- Naltrexone/pharmacology
- Narcotic Antagonists/metabolism
- Narcotic Antagonists/pharmacology
- Norepinephrine/metabolism
- Norepinephrine Plasma Membrane Transport Proteins/metabolism
- Piperidines/metabolism
- Piperidines/pharmacology
- Protein Binding
- Receptors, Adrenergic, alpha/metabolism
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/metabolism
- Tetrahydroisoquinolines/metabolism
- Tetrahydroisoquinolines/pharmacology
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Affiliation(s)
- Thomas A. Munro
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
- School of Chemistry and Bio21 Institute, University of Melbourne, Parkville, Australia
- * E-mail:
| | - Xi-Ping Huang
- National Institute of Mental Health Psychoactive Drug Screening Program and Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Carmela Inglese
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari, Bari, Italy
| | - Maria Grazia Perrone
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari, Bari, Italy
| | - Ashlee Van't Veer
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - F. Ivy Carroll
- Center for Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina, United States of America
| | - Cécile Béguin
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - William A. Carlezon
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Nicola A. Colabufo
- Dipartimento di Farmacia-Scienze del Farmaco, Università degli Studi di Bari, Bari, Italy
| | - Bruce M. Cohen
- McLean Hospital, Belmont, Massachusetts, United States of America
- Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Bryan L. Roth
- National Institute of Mental Health Psychoactive Drug Screening Program and Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
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Smith FG, Qi W. Cardiorenal Effects of Kappa Opioid Peptides During Ontogeny. Pharmaceuticals (Basel) 2011. [PMCID: PMC4052547 DOI: 10.3390/ph4010154] [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] [Indexed: 11/19/2022] Open
Abstract
This review focuses on the physiological roles for kappa opioid receptors (KORs) in adult animals and humans, as well as in the developing newborn animal. Our recent findings have provided new information that under physiological conditions in conscious newborn animals, activation of KORs with the selective agonist, U-50488H, results in an aquaresis, as previously observed in adult animals and humans. In addition, we have shown in conscious lambs that KORs modulate systemic and renal haemodynamics as well as the arterial baroreflex control of heart rate, providing a previously unidentified role for KORs.
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Runyon SP, Brieaddy LE, Mascarella SW, Thomas JB, Navarro HA, Howard JL, Pollard GT, Carroll FI. Analogues of (3R)-7-hydroxy-N-[(1S)-1-{[(3R,4R)-4-(3-hydroxyphenyl)-3,4-dimethyl-1-piperidinyl]methyl}-2-methylpropyl)-1,2,3,4-tetrahydro-3-isoquinolinecarboxamide (JDTic). Synthesis and in vitro and in vivo opioid receptor antagonist activity. J Med Chem 2010; 53:5290-301. [PMID: 20568781 DOI: 10.1021/jm1004978] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of compounds 6, 7a,b, 8a,b, 9a,b, and 10a,b where the amino -NH- group of JDTic (3) was replaced with an aromatic horizontal lineCH-, CH(2), O, S, or SO group was accomplished and used to further characterize the SAR of the compound 3 class of kappa opioid receptor antagonists. All of the compounds showed subnanomolar to low nanomolar K(e) values at the kappa opioid receptor. The most potent compound was 7a, where the amino -NH- group of 3 was replaced by a methylene (-CH(2)-) group. This compound had a K(e) = 0.18 nM and was 37- and 248-fold selective for the kappa relative to the mu and delta opioid receptors, respectively. Similar to compound 3, compound 7a antagonized selective kappa agonist U50,488-induced diuresis after sc administration in rats. In contrast to 3, where kappa antagonist activity lasted for three weeks, compound 7a did not show any kappa antagonist activity after one week.
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Affiliation(s)
- Scott P Runyon
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina 27709, USA
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Distrutti E, Cipriani S, Renga B, Mencarelli A, Migliorati M, Cianetti S, Fiorucci S. Hydrogen sulphide induces micro opioid receptor-dependent analgesia in a rodent model of visceral pain. Mol Pain 2010; 6:36. [PMID: 20540729 PMCID: PMC2908066 DOI: 10.1186/1744-8069-6-36] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Accepted: 06/11/2010] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Hydrogen sulphide (H2S) is a gaseous neuro-mediator that exerts analgesic effects in rodent models of visceral pain by activating KATP channels. A body of evidence support the notion that KATP channels interact with endogenous opioids. Whether H2S-induced analgesia involves opioid receptors is unknown. METHODS The perception of painful sensation induced by colorectal distension (CRD) in conscious rats was measured by assessing the abdominal withdrawal reflex. The contribution of opioid receptors to H2S-induced analgesia was investigated by administering rats with selective mu, kappa and delta opioid receptor antagonists and antisenses. To investigate whether H2S causes mu opioid receptor (MOR) transactivation, the neuronal like cells SKNMCs were challenged with H2S in the presence of MOR agonist (DAMGO) or antagonist (CTAP). MOR activation and phosphorylation, its association to beta arrestin and internalization were measured. RESULTS H2S exerted a potent analgesic effects on CRD-induced pain. H2S-induced analgesia required the activation of the opioid system. By pharmacological and molecular analyses, a robust inhibition of H2S-induced analgesia was observed in response to central administration of CTAP and MOR antisense, while kappa and delta receptors were less involved. H2S caused MOR transactivation and internalization in SKNMCs by a mechanism that required AKT phosphorylation. MOR transactivation was inhibited by LY294002, a PI3K inhibitor, and glibenclamide, a KATP channels blocker. CONCLUSIONS This study provides pharmacological and molecular evidence that antinociception exerted by H2S in a rodent model of visceral pain is modulated by the transactivation of MOR. This observation provides support for development of new pharmacological approaches to visceral pain.
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Affiliation(s)
- Eleonora Distrutti
- S.C. di Gastroenterologia, Azienda Ospedaliera di Perugia, Perugia, Italia.
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12
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Beardsley PM, Pollard GT, Howard JL, Carroll FI. Effectiveness of analogs of the kappa opioid receptor antagonist (3R)-7-hydroxy-N-((1S)-1-{[(3R,4R)-4-(3-hydroxyphenyl)-3,4-dimethyl-1-piperidinyl]methyl}-2-methylpropyl)-1,2,3,4-tetrahydro-3-isoquinolinecarboxamide (JDTic) to reduce U50,488-induced diuresis and stress-induced cocaine reinstatement in rats. Psychopharmacology (Berl) 2010; 210:189-98. [PMID: 20372878 PMCID: PMC2872796 DOI: 10.1007/s00213-010-1846-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Accepted: 03/21/2010] [Indexed: 11/27/2022]
Abstract
RATIONALE The kappa opioid receptor (KOR) antagonist, JDTic, was reported to prevent stress-induced reinstatement of cocaine-maintained responding and to have antidepressant-like effects. OBJECTIVES Our objectives were to determine whether analogs of JDTic retained KOR antagonist activity and whether an orally effective analog prevented footshock-induced cocaine reinstatement. METHODS RTI-194 (i.g. 1-30 mg/kg, s.c. 0.3-10 mg/kg, and i.p. 30 mg/kg), RTI-212 (s.c. 0.3-10 mg/kg and i.p. 30 mg/kg), and RTI-230 (i.g. 3-30 mg/kg and i.p. 1-30 mg/kg) were evaluated for their ability to block diuresis induced by 10-mg/kg U50,488 in rats. RTI-194 was additionally evaluated i.g. (3-100 mg/kg) for its ability to prevent footshock-induced reinstatement of responding previously reinforced with 0.5-mg/kg/inf cocaine. RESULTS RTI-194 significantly (p < 0.05) attenuated U50,488-induced diuresis when given i.g., s.c., and i.p. RTI-194s effectiveness increased 1 week following administration. RTI-212 was ineffective. RTI-230 was ineffective when given i.g., but blocked diuresis at 24 h and 8 days (1, 10, and 30 mg/kg), 15 days (10 and 30 mg/kg), 22 and 29 days (30 mg/kg) following i.p. administration. Footshock reinstated responding in vehicle-but not RTI-194 (30 and 100 mg/kg)-treated rats. CONCLUSIONS RTI-194 and RTI-230 are effective KOR antagonists, and RTI-194 is now included with JDTic as the only reported compounds capable of antagonizing the KOR following oral administration. The failure of stress to reinstate cocaine seeking in rats treated with RTI-194 is consistent with results reported with JDTic, although it had less efficacy in lowering response levels than JDTic, suggesting a diminished overall effectiveness relative to it.
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Affiliation(s)
- Patrick M. Beardsley
- Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA. VCU Institute for Drug and Alcohol Studies, Richmond, VA, USA
| | | | | | - F. Ivy Carroll
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, NC, USA
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Schunk E, Aigner C, Stefanova N, Wenning G, Herzog H, Schwarzer C. Kappa opioid receptor activation blocks progressive neurodegeneration after kainic acid injection. Hippocampus 2010; 21:1010-20. [PMID: 21391243 DOI: 10.1002/hipo.20813] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2010] [Indexed: 11/07/2022]
Abstract
We recently demonstrated that endogenous prodynorphin-derived peptides mediate anticonvulsant, antiepileptogenic and neuroprotective effects via kappa opioid receptors (KOP). Here we show acute and delayed neurodegeneration and its pharmacology after local kainic acid injection in prodynorphin knockout and wild-type mice and neuroprotective effect(s) of KOP activation in wild-type mice. Prodynorphin knockout and wild-type mice were injected with kainic acid (3 nmoles in 50 nl saline) into the stratum radiatum of CA1 of the right dorsal hippocampus. Knockout mice displayed significantly more neurodegeneration of pyramidal cells and interneurons than wild-type mice 2 days after treatment. This phenotype could be mimicked in wild-type animals by treatment with the KOP antagonist GNTI and rescued in knockout animals by the KOP agonist U-50488. Minor differences in neurodegeneration remained 3 weeks after treatment, mostly because of higher progressive neurodegeneration in wild-type mice compared with prodynorphin-deficient animals. In wild-type mice progressive neurodegeneration, but not acute neuronal loss, could be mostly blocked by U-50488 treatment. Our data suggest that endogenous prodynorphin-derived peptides sufficiently activate KOP receptors during acute seizures, and importantly in situations of reduced dynorphinergic signaling-like in epilepsy-the exogenous activation of KOP receptors might also have strong neuroprotective effects during excitotoxic events.
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Affiliation(s)
- Eduard Schunk
- Department of Pharmacology, Innsbruck Medical University, A-6020 Innsbruck, Austria
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14
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Prodynorphin-derived peptides are critical modulators of anxiety and regulate neurochemistry and corticosterone. Neuropsychopharmacology 2009; 34:775-85. [PMID: 18800067 PMCID: PMC2873573 DOI: 10.1038/npp.2008.142] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Stress and anxiety are mainly regulated by amygdala and hypothalamic circuitries involving several neurotransmitter systems and providing physiological responses to peripheral organs via the hypothalamic-pituitary-adrenal axis and other pathways. The role of endogenous opioid peptides in this process is largely unknown. Here we show for the first time that anxiolytic parameters of explorative behavior in mice lacking prodynorphin were increased 2-4-fold in the open field, the elevated plus maze and the light-dark test. Consistent with this, treatment of wild-type mice with selective kappa-opioid receptor antagonists GNTI or norbinaltorphimine showed the same effects. Furthermore, treatment of prodynorphin knockout animals with U-50488H, a selective kappa-opioid receptor agonist, fully reversed their anxiolytic phenotype. These behavioral data are supported by an approximal 30% reduction in corticotropin-releasing hormone (CRH) mRNA expression in the hypothalamic paraventricular nucleus and central amygdala and an accompanying 30-40% decrease in corticosterone serum levels in prodynorphin knockout mice. Although stress-induced increases in corticosterone levels were attenuated in prodynorphin knockout mice, they were associated with minor increases in depression-like behavior in the tail suspension and forced swim tests. Taken together, our data suggest a pronounced impact of endogenous prodynorphin-derived peptides on anxiety, but not stress coping ability and that these effects are mediated via kappa-opioid receptors. The delay in the behavioral response to kappa-opioid receptor agonists and antagonist treatment suggests an indirect control level for the action of dynorphin, probably by modulating the expression of CRH or neuropeptide Y, and subsequently influencing behavior.
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15
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Abstract
Current pharmacotherapy for bipolar disorder is generally unsatisfactory for a large number of patients. Even with adequate modern bipolar pharmacological therapies, many afflicted individuals continue to have persistent mood episode relapses, residual symptoms, functional impairment, and psychosocial disability. Creating novel therapeutics for bipolar disorder is urgently needed. Promising drug targets and compounds for bipolar disorder worthy of further study include both systems and intracellular pathways and targets. Specifically, the purinergic system, the dynorphin opioid neuropeptide system, the cholinergic system (muscarinic and nicotinic systems), the melatonin and serotonin [5-hydroxytryptamine receptor 2C] system, the glutamatergic system, and the hypothalamic-pituitary adrenal axis have all been implicated. Intracellular pathways and targets worthy of further study include glycogen synthase kinase-3 protein, protein kinase C, and the arachidonic acid cascade.
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Affiliation(s)
- Carlos A Zarate
- Laboratory of Molecular Pathophysiology and Experimental Therapeutics, Mood and Anxiety Disorders Research Program, National Institute of Mental Health, Bethesda, MD, USA.
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16
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Qi W, Ebenezar KK, Samhan MA, Smith FG. Renal responses to the kappa-opioid-receptor agonist U-50488H in conscious lambs. Am J Physiol Regul Integr Comp Physiol 2007; 293:R162-8. [PMID: 17409260 DOI: 10.1152/ajpregu.00863.2006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In adult animals and humans, activation of kappa-opioid receptors results in a diuresis. The aim of the present study was to investigate whether kappa-opioids are also diuretic early in life and whether this is altered during postnatal maturation. Therefore, the renal effects of the kappa-opioid-receptor agonist U-50488H were measured in two separate age groups of conscious lambs at two stages of postnatal maturation (approximately 1 wk and approximately 6 wk) under physiological conditions. To evaluate whether the renal responses to U-50488H resulted from receptor-dependent effects, responses to U-50488H were also tested in the presence of the specific kappa-opioid-receptor antagonist 5'-guanidinonaltrindole (GNTI). Urinary flow rate, free water clearance, and electrolyte excretions and clearances were measured for 30 min before and for 90 min after intravenous injection of U-50488H or vehicle. An increase in urinary flow rate accompanied by an increase in free water clearance occurred in response to administration of U-50488H but not vehicle. There were no effects of U-50488H on electrolyte excretions or clearances at either 1 or 6 wk of postnatal life. Although there were no effects of GNTI on any of the measured or calculated variables, the aforementioned diuretic response to U-50488H was abolished by pretreatment with GNTI in both age groups. We conclude that kappa-opioid receptors are diuretic early in life and that this response does not appear to be altered as postnatal maturation proceeds. Therefore, these data provide evidence that activation of kappa-opioid receptors early in life may lead to alterations in fluid balance.
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Affiliation(s)
- Wei Qi
- Department of Physiology and Biophysics, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada
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17
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Loacker S, Sayyah M, Wittmann W, Herzog H, Schwarzer C. Endogenous dynorphin in epileptogenesis and epilepsy: anticonvulsant net effect via kappa opioid receptors. ACTA ACUST UNITED AC 2007; 130:1017-28. [PMID: 17347252 DOI: 10.1093/brain/awl384] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Neuropsychiatric disorders are one of the main challenges of human medicine with epilepsy being one of the most common serious disorders of the brain. Increasing evidence suggest neuropeptides, particularly the opioids, play an important role in epilepsy. However, little is known about the mechanisms of the endogenous opioid system in epileptogenesis and epilepsy. Therefore, we investigated the role of endogenous prodynorphin-derived peptides in epileptogenesis, acute seizure behaviour and epilepsy in prodynorphin-deficient mice. Compared with wild-type littermates, prodynorphin knockout mice displayed a significantly reduced seizure threshold as assessed by tail-vein infusion of the GABA(A) antagonist pentylenetetrazole. This phenotype could be entirely rescued by the kappa receptor-specific agonist U-50488, but not by the mu receptor-specific agonist DAMGO. The delta-specific agonist SNC80 decreased seizure threshold in both genotypes, wild-type and knockout. Pre-treatment with the kappa selective antagonist GNTI completely blocked the rescue effect of U-50488. Consistent with the reduced seizure threshold, prodynorphin knockout mice showed faster seizure onset and a prolonged time of seizure activity after intracisternal injection of kainic acid. Three weeks after local injection of kainic acid into the stratum radiatum CA1 of the dorsal hippocampus, prodynorphin knockout mice displayed an increased extent of granule cell layer dispersion and neuronal loss along the rostrocaudal axis of the ipsi- and partially also of the contralateral hippocampus. In the classical pentylenetetrazole kindling model, dynorphin-deficient mice showed significantly faster kindling progression with six out of eight animals displaying clonic seizures, while none of the nine wild-types exceeded rating 3 (forelimb clonus). Taken together, our data strongly support a critical role for dynorphin in the regulation of hippocampal excitability, indicating an anticonvulsant role of kappa opioid receptors, thereby providing a potential target for antiepileptic drugs.
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MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology
- Analgesics/pharmacology
- Animals
- Benzamides/pharmacology
- Cell Count
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacology
- Enkephalins/genetics
- Enkephalins/metabolism
- Enkephalins/physiology
- Epilepsy, Temporal Lobe/metabolism
- Epilepsy, Temporal Lobe/physiopathology
- Guanidines
- Hippocampus/metabolism
- Kindling, Neurologic/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Morphinans
- Naltrexone/analogs & derivatives
- Naltrexone/pharmacology
- Nerve Degeneration/metabolism
- Piperazines/pharmacology
- Protein Precursors/genetics
- Protein Precursors/metabolism
- Protein Precursors/physiology
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/physiology
- Synaptic Transmission/physiology
- Time Factors
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Affiliation(s)
- Stephan Loacker
- Department of Pharmacology, Innsbruck Medical University, Innsbruck, Austria
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18
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Liang J, Li Y, Ping X, Yu P, Zuo Y, Wu L, Han JS, Cui C. The possible involvement of endogenous ligands for mu-, delta- and kappa-opioid receptors in modulating morphine-induced CPP expression in rats. Peptides 2006; 27:3307-14. [PMID: 17097192 DOI: 10.1016/j.peptides.2006.08.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Revised: 08/13/2006] [Accepted: 08/14/2006] [Indexed: 11/26/2022]
Abstract
Previous studies suggested that electroacupuncture (EA) can suppress opioid dependence by the release of endogenous opioid peptides. To explore the site of action and the receptors involved, we tried to inject highly specific agonists for mu-, delta- and kappa-opioid receptors into the CNS to test whether it can suppress morphine-induced conditioned place preference (CPP) in the rat. Male Sprague-Dawley rats were trained with 4 mg/kg morphine, i.p. for 4 days to establish the CPP model. This CPP can be prevented by (a) i.p. injection of 3 mg/kg dose of morphine, (b) intracerebroventricular (i.c.v.) injection of micrograms doses of the selective mu-opioid receptor agonist DAMGO, delta-agonist DPDPE or kappa-agonist U-50,488H or (c) microinjection of DAMGO, DPDPE or U50488H into the shell of the nucleus accumbens (NAc). The results suggest that the release of endogenous mu-, delta- and kappa-opioid agonists in the NAc shell may play a role for EA suppression of opiate addiction.
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MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology
- Animals
- Behavior, Animal/drug effects
- Behavior, Animal/physiology
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/physiology
- Enkephalin, D-Penicillamine (2,5)-/physiology
- Male
- Morphine/pharmacology
- Rats
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/physiology
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/physiology
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/physiology
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Affiliation(s)
- Jing Liang
- Neuroscience Research Institute and Department of Neurobiology, Peking University Health Science Center, Key Laboratory of Neuroscience, The Ministry of Education and Ministry of Public Health, 38 Xueyuan Road, Beijing 100083, PR China
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19
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Qi CT, Zou H, Zhang CH, Xie QL, Jin ML, Yu L. Effect of GNTI, a kappa opioid receptor antagonist, on MK-801-induced hyperlocomotion and stereotypy in mice. Acta Pharmacol Sin 2006; 27:1401-8. [PMID: 17049114 DOI: 10.1111/j.1745-7254.2006.00448.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
AIM To examine the effect of GNTI [5'-guanidinyl-17-(cyclopropylmethyl)-6,7- dehydro-4,5alpha-epoxy-3,14-dihydroxy-6,7-2',3'-indolomorphinan], a selective antagonist for the kappa opioid receptor, in the MK-801 (dizocilpine maleate)-induced behavioral model of psychosis in schizophrenia as a way to explore the involvement of the kappa opioid receptor in modulating psychotic symptoms of schizophrenia. METHODS Two doses of MK-801 (0.3 mg/kg and 0.6 mg/kg) were administered by systemic injection in mice to induce psychosis-like behavior as a rodent schizophrenia model, preceded by an injection of different doses of GNTI. Both locomotion and stereotypy were measured as the behavioral endpoints for quantitative analysis. RESULTS GNTI inhibited MK-801-induced hyperlocomotion and stereotypy. In particular, GNTI showed differential modulation of stereotypy induced by 0.3 mg/kg vs 0.6 mg/kg MK-801. CONCLUSION Antagonism of kappa opioid receptors attenuates MK-801-induced behavior, suggesting a potential involvement of the kappa opioid receptor in psychosis-like symptoms of schizophrenia. GNTI appears to be a useful pharmacological tool to explore the kappa opioid receptor function in vivo.
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Affiliation(s)
- Chun-ting Qi
- Research Center for Biotechnology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200233, China
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20
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Abstract
The purpose of the present study was to determine the cardiovascular effects of the kappa-opioid receptor agonist U-50488H at two stages of postnatal maturation under physiological conditions. Experiments were carried out firstly to define systemic and renal haemodynamic responses to kappa-opioid receptor activation and, secondly, to determine whether these effects are altered during postnatal maturation. To investigate whether the responses to U-50488H resulted from receptor-dependent effects, responses to U-50488H were also tested in the presence of the specific kappa-opioid receptor antagonist 5'-guanidinonaltrindole (GNTI). Experiments were carried out in two groups of conscious, chronically instrumented lambs aged approximately 1 and approximately 6 weeks. Mean arterial pressure, mean venous pressure and renal blood flow (RBF) were measured for 30 min before and 90 min after i.v. injection of U-50488H or vehicle. Heart rate increased in both age groups of lambs within 10 min of U-50488H administration. Mean arterial pressure decreased for 50 min following U-50488H administration at 1 week but, in contrast, increased transiently at 10 min in 6-week-old lambs, returning to control levels by 20 min. In both age groups, there was a sustained decrease in RBF following U-50488H. The aforementioned responses to U-50488H were abolished by pretreatment with GNTI. These data provide the first measurements of systemic and renal haemodynamic responses to kappa-opioid receptor activation during postnatal maturation.
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MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology
- Aging/physiology
- Analgesics, Non-Narcotic/pharmacology
- Animals
- Blood Circulation/drug effects
- Blood Circulation/physiology
- Blood Pressure/drug effects
- Blood Pressure/physiology
- Dynorphins/pharmacology
- Guanidines/pharmacology
- Heart Rate/drug effects
- Heart Rate/physiology
- Hemodynamics/drug effects
- Hemodynamics/physiology
- Kidney/blood supply
- Kidney/drug effects
- Naltrexone/analogs & derivatives
- Naltrexone/pharmacology
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, kappa/physiology
- Regional Blood Flow/drug effects
- Regional Blood Flow/physiology
- Sheep
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Affiliation(s)
- Wei Qi
- Department of Physiology & Biophysics, Faculty of Medicine, University of Calgary, Alberta T2N 4N1, Canada
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21
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Correia MLG, Haynes WG. Emerging drugs for obesity: linking novel biological mechanisms to pharmaceutical pipelines. Expert Opin Emerg Drugs 2006; 10:643-60. [PMID: 16083333 DOI: 10.1517/14728214.10.3.643] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Obesity is associated with hypertension, diabetes, dyslipidaemias and metabolic syndrome, and causes substantial morbidity and mortality from cardiovascular and other diseases. The cost to treat obesity and its complications in the US has increased steeply and is currently estimated to be USD 100 billion. Current therapy for obesity is mainly based on changes in lifestyle that often fail. Existing pharmacological treatment is marginally efficient and poorly tolerated. The discovery of leptin and related neural mechanisms of energy metabolism regulation has opened the doors to potential targets for new antiobesity drugs. In this review, new pharmacological targets are discussed and an update on the development of emerging antiobesity drugs is provided. Despite intense investigation, the pipelines for antiobesity drugs in late stages of development are relatively empty. Breakthrough treatments for obesity may take some years to emerge. Clinical trials will be necessary to clarify the impact of new antiobesity drugs on hard cardiovascular and metabolic end points.
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Affiliation(s)
- Marcelo L G Correia
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA.
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22
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Metcalf MD, Coop A. Kappa opioid antagonists: past successes and future prospects. AAPS JOURNAL 2005. [PMID: 16353947 DOI: 10.1208/aapsj070371].] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Antagonists of the kappa opioid receptor were initially investigated as pharmacological tools that would reverse the effects of kappa opioid receptor agonists. In the years following the discovery of the first selective kappa opioid antagonists, much information about their chemistry and pharmacology has been elicited and their potential therapeutic uses have been investigated. The review presents the current chemistry, ligand-based structure activity relationships, and pharmacology of the known nonpeptidic selective kappa opioid receptor antagonists. This manuscript endeavors to provide the reader with a useful reference of the investigations made to define the structure-activity relationships and pharmacology of selective kappa opioid receptor antagonists and their potential uses as pharmacological tools and as therapeutic agents in the treatment of disease states.
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Affiliation(s)
- Matthew D Metcalf
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD 21201, USA
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23
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Metcalf MD, Coop A. Kappa opioid antagonists: past successes and future prospects. AAPS J 2005. [PMID: 16353947 DOI: 10.1208/aapsj070371]] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Antagonists of the kappa opioid receptor were initially investigated as pharmacological tools that would reverse the effects of kappa opioid receptor agonists. In the years following the discovery of the first selective kappa opioid antagonists, much information about their chemistry and pharmacology has been elicited and their potential therapeutic uses have been investigated. The review presents the current chemistry, ligand-based structure activity relationships, and pharmacology of the known nonpeptidic selective kappa opioid receptor antagonists. This manuscript endeavors to provide the reader with a useful reference of the investigations made to define the structure-activity relationships and pharmacology of selective kappa opioid receptor antagonists and their potential uses as pharmacological tools and as therapeutic agents in the treatment of disease states.
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Affiliation(s)
- Matthew D Metcalf
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, Baltimore, MD 21201, USA
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24
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Metcalf MD, Coop A. Kappa opioid antagonists: past successes and future prospects. AAPS JOURNAL 2005; 7:E704-22. [PMID: 16353947 PMCID: PMC2751273 DOI: 10.1208/aapsj070371] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Antagonists of the kappa opioid receptor were initially investigated as pharmacological tools that would reverse the effects of kappa opioid receptor agonists. In the years following the discovery of the first selective kappa opioid antagonists, much information about their chemistry and pharmacology has been elicited and their potential therapeutic uses have been investigated. The review presents the current chemistry, ligand-based structure activity relationships, and pharmacology of the known nonpeptidic selective kappa opioid receptor antagonists. This manuscript endeavors to provide the reader with a useful reference of the investigations made to define the structure-activity relationships and pharmacology of selective kappa opioid receptor antagonists and their potential uses as pharmacological tools and as therapeutic agents in the treatment of disease states.
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Affiliation(s)
- Matthew D. Metcalf
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, 21201 Baltimore, MD
| | - Andrew Coop
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, 20 Penn Street, 21201 Baltimore, MD
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25
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Israel Y, Kandov Y, Khaimova E, Kest A, Lewis SR, Pasternak GW, Pan YX, Rossi GC, Bodnar RJ. NPY-induced feeding: pharmacological characterization using selective opioid antagonists and antisense probes in rats. Peptides 2005; 26:1167-75. [PMID: 15949635 DOI: 10.1016/j.peptides.2005.01.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 01/20/2005] [Accepted: 01/24/2005] [Indexed: 11/17/2022]
Abstract
The ability of neuropeptide Y to potently stimulate food intake is dependent in part upon the functioning of mu and kappa opioid receptors. The combined use of selective opioid antagonists directed against mu, delta or kappa receptors and antisense probes directed against specific exons of the MOR-1, DOR-1, KOR-1 and KOR-3/ORL-1 opioid receptor genes has been successful in characterizing the precise receptor subpopulations mediating feeding elicited by opioid peptides and agonists as well as homeostatic challenges. The present study examined the dose-dependent (5-80 nmol) cerebroventricular actions of general and selective mu, delta, and kappa1 opioid receptor antagonists together with antisense probes directed against each of the four exons of the MOR-1 opioid receptor gene and each of the three exons of the DOR-1, KOR-1, and KOR-3/ORL-1 opioid receptor genes upon feeding elicited by cerebroventricular NPY (0.47 nmol, 2 ug). NPY-induced feeding was dose-dependently decreased and sometimes eliminated following pretreatment with general, mu, delta, and kappa1 opioid receptor antagonists. Moreover, NPY-induced feeding was significantly and markedly reduced by antisense probes directed against exons 1, 2, and 3 of the MOR-1 gene, exons 1 and 2 of the DOR-1 gene, exons 1, 2, and 3 of the KOR-1 gene, and exon 3 of the KOR-3/ORL-1 gene. Thus, whereas the opioid peptides, beta-endorphin and dynorphin A(1-17) elicit feeding responses that are respectively more dependent upon mu and kappa opioid receptors and their genes, the opioid mediation of NPY-induced feeding appears to involve all three major opioid receptor subtypes in a manner similar to that observed for feeding responses following glucoprivation or lipoprivation.
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Affiliation(s)
- Y Israel
- Department of Psychology, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY 11367, USA
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26
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Carroll I, Thomas JB, Dykstra LA, Granger AL, Allen RM, Howard JL, Pollard GT, Aceto MD, Harris LS. Pharmacological properties of JDTic: a novel kappa-opioid receptor antagonist. Eur J Pharmacol 2005; 501:111-9. [PMID: 15464069 DOI: 10.1016/j.ejphar.2004.08.028] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2004] [Revised: 08/03/2004] [Accepted: 08/05/2004] [Indexed: 10/26/2022]
Abstract
Biological studies were conducted on (3R)-7-Hydroxy-N-[(1S)-1-[[(3R,4R)-4-(3-hydroxyphenyl)-3,4-dimethyl-1-piperidinyl]methyl]-2-methylpropyl]-1,2,3,4-tetrahydro-3-isoquinoline-carboxamide (JDTic), the first potent kappa-selective opioid receptor antagonist not derived from an opiate class of compounds. In the mouse tail-flick test, JDTic, administered subcutaneously (s.c.), blocked anticociceptive activity for up to 2 weeks. When JDTic was administered either s.c. or p.o. 24 h before the selective KOP (kappa)-opioid receptor agonist, enadoline, AD(50s) of 4.1 and 27.3, respectively, were obtained. A time-course study of JDTic versus enadoline indicated significant antagonist p.o. activity up to 28 days. In contrast, JDTic, s.c., failed to antagonize the analgesic effects of the selective MOP mu-opioid receptor agonist, sufentanil. In the squirrel monkey shock titration antinociception test, JDTic given intramuscularly (i.m.) shifted the trans-3,4-dichloro-N-methyl-N-(2-[1-pyrrolidinyl] cyclohexyl) benzeneacetamide (U50,488) dose-effect curve to the right. In the U50,488-induced diuresis rat test, JDTic, s.c., suppressed diuretic activity with a greater potency than that of nor-binaltorphimine (nor-BNI). Thus, JDTic is a potent long- and orally acting selective kappa-opioid antagonist.
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Affiliation(s)
- Ivy Carroll
- Organic and Medicinal Chemistry, Research Triangle Institute, Research Triangle Park, North Carolina, USA.
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27
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Dodo KI, Izumi T, Ueda H, Bungo T. Response of neuropeptide Y-induced feeding to μ-, δ- and κ-opioid receptor antagonists in the neonatal chick. Neurosci Lett 2005; 373:85-8. [PMID: 15567558 DOI: 10.1016/j.neulet.2004.09.065] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Revised: 08/13/2004] [Accepted: 09/27/2004] [Indexed: 11/16/2022]
Abstract
It is known that opioid antagonists reduce the orexigenic effect of neropeptide Y (NPY) in mammals. We studied the effect of three opioid antagonists on NPY-induced feeding in male broiler chicks. Beta-funaltrexamine (beta-FNA), naloxonazine (NAL), ICI-174,864 (ICI) or nor-binaltorphimine (nor-BNI), antagonists of mu-, mu1-, delta- or kappa-receptors, and NPY were co-injected in chicks. Food intake was measured 30 min after treatment. Co-injection of beta-FNA or NAL was effective in reducing NPY-induced feeding, whereas ICI and nor-BNI had little effect on NPY-induced feeding. These data suggest that the mu-opioid receptor, especially the mu1-opioid has some relation to NPY-induced feeding, and implies that an endogenous ligand, such as beta-endorphin, participates in the orexigenic effect of NPY in neonatal chicks.
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MESH Headings
- Animals
- Animals, Newborn
- Chickens/physiology
- Feeding Behavior/drug effects
- Male
- Narcotic Antagonists/pharmacology
- Neuropeptide Y/metabolism
- Neuropeptide Y/pharmacology
- Receptors, Opioid/metabolism
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/metabolism
- beta-Endorphin/drug effects
- beta-Endorphin/metabolism
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Affiliation(s)
- Koh-Ichi Dodo
- Laboratory of Animal Science, Department of Agrobiological Science, Faculty of Agriculture, Ehime University, Tarumi 3-5-7 Matsuyama, Ehime 790-8566, Japan
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28
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Bodnar RJ. Endogenous opioids and feeding behavior: a 30-year historical perspective. Peptides 2004; 25:697-725. [PMID: 15165728 DOI: 10.1016/j.peptides.2004.01.006] [Citation(s) in RCA: 124] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2004] [Revised: 01/15/2004] [Accepted: 01/16/2004] [Indexed: 11/25/2022]
Abstract
This invited review, based on the receipt of the Third Gayle A. Olson and Richard D. Olson Prize for the publication of the outstanding behavioral article published in the journal Peptides in 2002, examines the 30-year historical perspective of the role of the endogenous opioid system in feeding behavior. The review focuses on the advances that this field has made over the past 30 years as a result of the timely discoveries that were made concerning this important neuropeptide system, and how these discoveries were quickly applied to the analysis of feeding behavior and attendant homeostatic processes. The discoveries of the opioid receptors and opioid peptides, and the establishment of their relevance to feeding behavior were pivotal in studies performed in the 1970s. The 1980s were characterized by the establishment of opioid receptor subtype agonists and antagonists and their relevance to the modulation of feeding behavior as well as by the use of general opioid antagonists in demonstrating the wide array of ingestive situations and paradigms involving the endogenous opioid system. The more recent work from the 1990s to the present, utilizes the advantages created by the cloning of the opioid receptor genes, the development of knockout and knockdown techniques, the systematic utilization of a systems neuroscience approach, and establishment of the reciprocity of how manipulations of opioid peptides and receptors affect feeding behavior with how feeding states affect levels of opioid peptides and receptors. The role of G-protein effector systems in opioid-mediated feeding responses, which was the subject of the prize-winning article, is then reviewed.
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Subprogram, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY 11367, USA.
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29
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Levine AS, Jewett DC, Cleary JP, Kotz CM, Billington CJ. Our journey with neuropeptide Y: effects on ingestive behaviors and energy expenditure. Peptides 2004; 25:505-10. [PMID: 15134869 DOI: 10.1016/j.peptides.2004.01.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Clark and colleagues first described the robust orexigenic effects of neuropeptide Y (NPY) in 1984. Our group as well as Stanley et al. confirmed these effects in the same year. During the next 20 years, we investigated the effects of NPY on diet preferences, opioid-related feeding, distributed neural feeding networks, energy metabolism, motivation and discriminative stimulus effects. These data together with data from other laboratories indicate that NPY increases feeding, even when rats work for food; that NPY decreases energy expenditure, particularly by altering thermogenesis; and that NPY's effects on energy metabolism are mediated by a widely distributed neural network involving other neuroregulators known to be involved in energy regulation.
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Affiliation(s)
- Allen S Levine
- Minnesota Obesity Center, Veterans Affairs Medical Center, and Department of Psychology, University of Minnesota, Minneapolis 55455, USA.
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30
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Obara I, Mika J, Schäfer MKH, Przewlocka B. Antagonists of the kappa-opioid receptor enhance allodynia in rats and mice after sciatic nerve ligation. Br J Pharmacol 2003; 140:538-46. [PMID: 12970097 PMCID: PMC1574046 DOI: 10.1038/sj.bjp.0705427] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The administration of kappa-opioid receptor antagonists, nor-binaltorphimine (norBNI) and 5'-guanidinonaltrindole (GNTI) enhanced allodynia in rats and mice after sciatic nerve ligation. In order to understand the mechanism underlying this effect, we examined the possible involvement of the endogenous ligand of kappa-opioid receptor dynorphin. The experiments were carried out on male Wistar rats and on Albino-Swiss mice. The rats had been implanted with a catheter 7 days earlier in the subarachnoid space of the spinal cord. Intrathecal (i.t.) administrations in mice were made by lumbar puncture. The animals were i.t. injected with norBNI, GNTI (kappa-opioid receptor antagonists), dynorphin A1-17 antiserum (DYN A/S), ketamine (NMDA receptor antagonist) and their combinations. The nociceptive sensitivity was assessed using the mechanical (von Frey) and thermal allodynia tests on days 2-4 and 8-10 after the sciatic nerve ligation. Both antagonists, norBNI and GNTI, significantly enhanced mechanical and thermal allodynia in rats and mice with neuropathic pain. The potentiation of allodynia after the administration of norBNI or GNTI was inhibited by earlier administration of DYN A/S or by ketamine. Our results suggest that allodynia is mediated through nonopioid effect of the endogenous opioid peptide, dynorphin. The nonopioid action is potentiated by the blockade of kappa-opioid receptors, and corresponding to the elevation of prodynorphin mRNA level in neuropathic pain. Furthermore, the potentiation of allodynia after the administration of the above drugs appears to be mediated through the activation of NMDA receptors directly by dynorphin.
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Affiliation(s)
- I Obara
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343 Krakow, Poland
| | - J Mika
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343 Krakow, Poland
- Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps University, 35033 Marburg, Germany
| | - M K -H Schäfer
- Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps University, 35033 Marburg, Germany
| | - B Przewlocka
- Department of Molecular Neuropharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343 Krakow, Poland
- Author for correspondence:
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31
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Mague SD, Pliakas AM, Todtenkopf MS, Tomasiewicz HC, Zhang Y, Stevens WC, Jones RM, Portoghese PS, Carlezon WA. Antidepressant-like effects of kappa-opioid receptor antagonists in the forced swim test in rats. J Pharmacol Exp Ther 2003; 305:323-30. [PMID: 12649385 DOI: 10.1124/jpet.102.046433] [Citation(s) in RCA: 404] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We showed previously that cAMP response element-binding protein (CREB) within the nucleus accumbens (NAc) of rats regulates immobility in the forced swim test (FST), an assay used to study depression. Because CREB regulates expression of dynorphin (which acts at kappa-opioid receptors) in NAc neurons, these findings raised the possibility that kappa-receptors mediate immobility behaviors in the FST. Here, we report that i.c.v. administration of the kappa-antagonist nor-binaltorphimine dose dependently decreased immobility in the FST, suggesting that it has antidepressant-like effects. Implicating a specific effect at kappa-receptors, similar antidepressant-like effects were seen after treatment with either of two novel, structurally dissimilar kappa-antagonists: 5'-guanidinonaltrindole, which was effective after i.c.v. but not systemic treatment, and 5'-acetamidinoethylnaltrindole (ANTI), which was potent and effective after systemic treatment. The behavioral effects of the kappa-antagonists resembled those of tricyclic antidepressants (desipramine) and selective serotonin reuptake inhibitors (fluoxetine and citalopram). Conversely, systemic administration of the kappa-agonist [5alpha,7alpha,8beta]-N-methyl-N-[7-[1-pyrrolidinyl]-1-oxaspiro[4.5]dec8-yl]-benzenacetamide (U-69593) dose dependently increased immobility in the FST, consistent with prodepressant-like effects. The effects of the kappa-ligands in the FST were not correlated with nonspecific effects on locomotor activity. Furthermore, the most potent and effective kappa-antagonist (ANTI) did not affect the rewarding impact of lateral hypothalamic brain stimulation at a dose with strong antidepressant-like effects. These findings are consistent with the hypothesis that CREB-mediated induction of dynorphin in the NAc "triggers" immobility behavior in the FST. Furthermore, they raise the possibility that kappa-antagonists may have efficacy as antidepressants, but lack stimulant or reward-related effects.
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Affiliation(s)
- Stephen D Mague
- Behavioral Genetics Laboratory, Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, Massachusetts 02478, USA
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Abstract
This paper is the twenty-fourth installment of the annual review of research concerning the opiate system. It summarizes papers published during 2001 that studied the behavioral effects of the opiate peptides and antagonists. The particular topics covered this year include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology(Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, CUNY, 65-30 Kissena Blvd., Flushing, NY 11367, USA.
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33
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Abstract
A variety of evidence suggests that endogenous opioid peptides play a role in the short-term control of eating. More recently, opioid receptor antagonists like naltrexone have been approved as a treatment for alcohol dependence. Here we review the evidence for a role of opioid peptides in both normal and abnormal eating and drinking behaviours and in particular try to identify the nature of the role of opioids in these behaviours. Particular attention is paid to the idea that opioid reward processes may be involved both in the short-term control of eating and hedonic aspects of alcohol consumption, and parallels are drawn between the effects of opiate antagonists on food pleasantness and the experience of drinking alcohol. The review also explores the extent to which data from studies using opiate antagonists and agonists provide evidence for a direct role of endogenous opioids in the control of ingestive behaviour, or alternatively whether these data may be better explained through non-specific effects such as the nausea commonly reported following administration of opiate antagonists. The review concludes that the present data suggests a single opioid mechanism is unlikely to explain all aspects of ingestive behaviour, but also concludes that opioid-mediated reward mechanisms play an important control in hedonic aspects of ingestion. The review also highlights the need for further empirical work in order to elucidate further the role of opioid peptides in human ingestive behaviour.
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Affiliation(s)
- Martin R Yeomans
- Laboratory of Experimental Psychology, University of Sussex, Brighton, Sussex BN1 9QG, UK.
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