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Rodríguez FD, Sánchez ML, Coveñas R. Neurotensin and Alcohol Use Disorders: Towards a Pharmacological Treatment. Int J Mol Sci 2023; 24:ijms24108656. [PMID: 37240004 DOI: 10.3390/ijms24108656] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/06/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
Harmful alcohol use is responsible for a group of disorders collectively named alcohol use disorders (AUDs), according to the DSM-5 classification. The damage induced by alcohol depends on the amount, time, and consumption patterns (continuous and heavy episodic drinking). It affects individual global well-being and social and familial environments with variable impact. Alcohol addiction manifests with different degrees of organ and mental health detriment for the individual, exhibiting two main traits: compulsive drinking and negative emotional states occurring at withdrawal, frequently causing relapse episodes. Numerous individual and living conditions, including the concomitant use of other psychoactive substances, lie in the complexity of AUD. Ethanol and its metabolites directly impact the tissues and may cause local damage or alter the homeostasis of brain neurotransmission, immunity scaffolding, or cell repair biochemical pathways. Brain modulator and neurotransmitter-assembled neurocircuitries govern reward, reinforcement, social interaction, and consumption of alcohol behaviors in an intertwined manner. Experimental evidence supports the participation of neurotensin (NT) in preclinical models of alcohol addiction. For example, NT neurons in the central nucleus of the amygdala projecting to the parabrachial nucleus strengthen alcohol consumption and preference. In addition, the levels of NT in the frontal cortex were found to be lower in rats bred to prefer alcohol to water in a free alcohol-water choice compared to wild-type animals. NT receptors 1 and 2 seem to be involved in alcohol consumption and alcohol effects in several models of knockout mice. This review aims to present an updated picture of the role of NT systems in alcohol addiction and the possible use of nonpeptide ligands modulating the activity of the NT system, applied to experimental animal models of harmful drinking behavior mimicking alcohol addiction leading to health ruin in humans.
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Affiliation(s)
- Francisco D Rodríguez
- Department of Biochemistry and Molecular Biology, Faculty of Chemical Sciences, University of Salamanca, 37008 Salamanca, Spain
- Group GIR-USAL: BMD (Bases Moleculares del Desarrollo), University of Salamanca, 37008 Salamanca, Spain
| | - Manuel Lisardo Sánchez
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute of Neurosciences of Castilla and León (INCYL), University of Salamanca, C/Pintor Fernando Gallego 1, 37007 Salamanca, Spain
| | - Rafael Coveñas
- Group GIR-USAL: BMD (Bases Moleculares del Desarrollo), University of Salamanca, 37008 Salamanca, Spain
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute of Neurosciences of Castilla and León (INCYL), University of Salamanca, C/Pintor Fernando Gallego 1, 37007 Salamanca, Spain
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Narendra S, Klengel C, Hamzeh B, Patel D, Otten J, Lardenoije R, Newman EL, Miczek KA, Klengel T, Ressler KJ, Suh J. Genome-wide transcriptomics of the amygdala reveals similar oligodendrocyte-related responses to acute and chronic alcohol drinking in female mice. Transl Psychiatry 2022; 12:476. [PMID: 36371333 PMCID: PMC9653459 DOI: 10.1038/s41398-022-02231-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 11/13/2022] Open
Abstract
Repeated excessive alcohol consumption is a risk factor for alcohol use disorder (AUD). Although AUD has been more common in men than women, women develop more severe behavioral and physical impairments. However, relatively few new therapeutics targeting development of AUD, particularly in women, have been validated. To gain a better understanding of molecular mechanisms underlying alcohol intake, we conducted a genome-wide RNA-sequencing analysis in female mice exposed to different modes (acute vs chronic) of ethanol drinking. We focused on transcriptional profiles in the amygdala including the central and basolateral subnuclei, brain areas previously implicated in alcohol drinking and seeking. Surprisingly, we found that both drinking modes triggered similar changes in gene expression and canonical pathways, including upregulation of ribosome-related/translational pathways and myelination pathways, and downregulation of chromatin binding and histone modification. In addition, analyses of hub genes and upstream regulatory pathways revealed that voluntary ethanol consumption affects epigenetic changes via histone deacetylation pathways, oligodendrocyte and myelin function, and the oligodendrocyte-related transcription factor, Sox17. Furthermore, a viral vector-assisted knockdown of Sox17 gene expression in the amygdala prevented a gradual increase in alcohol consumption during repeated accesses. Overall, these results suggest that the expression of oligodendrocyte-related genes in the amygdala is sensitive to voluntary alcohol drinking in female mice. These findings suggest potential molecular targets for future therapeutic approaches to prevent the development of AUD, due to repeated excessive alcohol consumption, particularly in women.
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Affiliation(s)
- Sharvari Narendra
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA
- Department of Bioinformatics, Northeastern University, Boston, MA, 02115, USA
| | - Claudia Klengel
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA
| | - Bilal Hamzeh
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA
| | - Drasti Patel
- Department of Bioinformatics, Northeastern University, Boston, MA, 02115, USA
| | - Joy Otten
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany
| | - Roy Lardenoije
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany
| | - Emily L Newman
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA
| | - Klaus A Miczek
- Psychology and Neuroscience Departments, Tufts University, Medford, MA, 02155, USA
| | - Torsten Klengel
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA
- Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Göttingen, Germany
| | - Kerry J Ressler
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA.
| | - Junghyup Suh
- Division of Depression and Anxiety Disorders, McLean Hospital, Department of Psychiatry, Harvard Medical School, Belmont, MA, 02478, USA.
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Ferraro L, Tiozzo Fasiolo L, Beggiato S, Borelli AC, Pomierny-Chamiolo L, Frankowska M, Antonelli T, Tomasini MC, Fuxe K, Filip M. Neurotensin: A role in substance use disorder? J Psychopharmacol 2016; 30:112-27. [PMID: 26755548 DOI: 10.1177/0269881115622240] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Neurotensin is a tridecapeptide originally identified in extracts of bovine hypothalamus. This peptide has a close anatomical and functional relationship with the mesocorticolimbic and nigrostriatal dopamine system. Neural circuits containing neurotensin were originally proposed to play a role in the mechanism of action of antipsychotic agents. Additionally, neurotensin-containing pathways were demonstrated to mediate some of the rewarding and/or sensitizing properties of drugs of abuse.This review attempts to contribute to the understanding of the role of neurotensin and its receptors in drug abuse. In particular, we will summarize the potential relevance of neurotensin, its related compounds and neurotensin receptors in substance use disorders, with a focus on the preclinical research.
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Affiliation(s)
- Luca Ferraro
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy Laboratory for Technologies of Advanced Therapies (LTTA), University of Ferrara, Ferrara, Italy
| | - Laura Tiozzo Fasiolo
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Sarah Beggiato
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Andrea C Borelli
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | | | - Malgorzata Frankowska
- Laboratory of Drug Addiction Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Tiziana Antonelli
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Maria C Tomasini
- Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
| | - Kjell Fuxe
- Department of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Malgorzata Filip
- Laboratory of Drug Addiction Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
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Vadnie CA, Park JH, Abdel Gawad N, Ho AMC, Hinton DJ, Choi DS. Gut-brain peptides in corticostriatal-limbic circuitry and alcohol use disorders. Front Neurosci 2014; 8:288. [PMID: 25278825 PMCID: PMC4166902 DOI: 10.3389/fnins.2014.00288] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 08/26/2014] [Indexed: 12/22/2022] Open
Abstract
Peptides synthesized in endocrine cells in the gastrointestinal tract and neurons are traditionally considered regulators of metabolism, energy intake, and appetite. However, recent work has demonstrated that many of these peptides act on corticostriatal-limbic circuitry and, in turn, regulate addictive behaviors. Given that alcohol is a source of energy and an addictive substance, it is not surprising that increasing evidence supports a role for gut-brain peptides specifically in alcohol use disorders (AUD). In this review, we discuss the effects of several gut-brain peptides on alcohol-related behaviors and the potential mechanisms by which these gut-brain peptides may interfere with alcohol-induced changes in corticostriatal-limbic circuitry. This review provides a summary of current knowledge on gut-brain peptides focusing on five peptides: neurotensin, glucagon-like peptide 1, ghrelin, substance P, and neuropeptide Y. Our review will be helpful to develop novel therapeutic targets for AUD.
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Affiliation(s)
- Chelsea A Vadnie
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Neurobiology of Disease Program, Mayo Clinic College of Medicine Rochester, MN, USA
| | - Jun Hyun Park
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Department of Psychiatry, Sanggye Paik Hospital, College of Medicine, InJe University Seoul, South Korea
| | - Noha Abdel Gawad
- Department of Psychiatry and Psychology, Mayo Clinic College of Medicine Rochester, MN, USA
| | - Ada Man Choi Ho
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Department of Psychiatry and Psychology, Mayo Clinic College of Medicine Rochester, MN, USA
| | - David J Hinton
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Neurobiology of Disease Program, Mayo Clinic College of Medicine Rochester, MN, USA
| | - Doo-Sup Choi
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine Rochester, MN, USA ; Neurobiology of Disease Program, Mayo Clinic College of Medicine Rochester, MN, USA ; Department of Psychiatry and Psychology, Mayo Clinic College of Medicine Rochester, MN, USA
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Li Z, Boules M, Richelson E. NT69L blocks ethanol-induced increase of dopamine and glutamate levels in striatum of mouse. Neurosci Lett 2010; 487:322-4. [PMID: 20974215 DOI: 10.1016/j.neulet.2010.10.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 10/05/2010] [Accepted: 10/16/2010] [Indexed: 12/16/2022]
Abstract
Recent study shows that NT69L, an analog of neurotensin (NT) (8-13), reduces ethanol consumption and preference in mice through modulation of neurotensin receptor subtype one. The current study showed that NT69L significantly decreased ethanol-induced increase of dopamine and glutamate levels in striatum of mouse. These data suggest that NT69L prevents ethanol consumption through the modulation of both dopaminergic and glutamatergic systems implicated in ethanol addiction. NT agonists may provide novel treatment for alcohol addiction.
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Affiliation(s)
- Zhimin Li
- Neuroscience Laboratory and Mayo Foundation for Medical Education and Research, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224, USA.
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Radcliffe RA, Bludeau P, Asperi W, Fay T, Deng XS, Erwin VG, Deitrich RA. Confirmation of quantitative trait loci for ethanol sensitivity and neurotensin receptor density in crosses derived from the inbred high and low alcohol sensitive selectively bred rat lines. Psychopharmacology (Berl) 2006; 188:343-54. [PMID: 16953387 DOI: 10.1007/s00213-006-0512-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2006] [Accepted: 07/09/2006] [Indexed: 11/28/2022]
Abstract
RATIONALE Genetically influenced alcohol sensitivity is thought to be an important risk factor for the development of alcoholism. An effective first step for identifying genes that mediate variation in alcohol sensitivity is through quantitative trait loci (QTL) mapping in model organisms. OBJECTIVE Fourteen provisional QTLs related to alcohol sensitivity were previously mapped in an F2 derived from the IHAS1 and ILAS1 rat lines. The objective of the current study was to confirm those QTLs in an independently derived F2 and in congenics that were bred for two of the loci. MATERIALS AND METHODS IHAS1 X ILAS1 F2 (n=450) were tested for alcohol-induced loss of righting reflex (LORR), blood ethanol concentration at regain of righting reflex (BECRR), sensitivity and acute tolerance on the Rotarod, and neurotensin receptor density (NTR1). Rats were genotyped at the 14 candidate loci and QTL mapping was conducted. Reciprocal congenic strains were bred for loci on chromosomes 2 and 5 and tested for LORR and BECRR. RESULTS Four LORR QTLs were mapped at the suggestive or significant level (chromosomes 2, 5, 12, and 13). BECRR was mapped to chromosomes 5, 12, and 13 either in the original or current experiment. Results of the congenic experiment also support QTLs for LORR and BECRR on chromosomes 2 and 5. QTLs for NTR1 density and behavior on the Rotarod were not confirmed. CONCLUSIONS QTL mapping in crosses derived from the IHAS1 and ILAS1 has successfully identified loci related to alcohol sensitivity. Recombinant congenics are now being bred to more finely map the confirmed QTLs.
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Affiliation(s)
- Richard A Radcliffe
- Department of Pharmaceutical Sciences, University of Colorado at Denver and Health Sciences Center, 4200 East Ninth Ave., Denver, CO, 80262, USA.
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Radcliffe RA, Erwin VG, Draski L, Hoffmann S, Edwards J, Deng XS, Bludeau P, Fay T, Lundquist K, Asperi W, Deitrich RA. Quantitative trait loci mapping for ethanol sensitivity and neurotensin receptor density in an F2 intercross derived from inbred high and low alcohol sensitivity selectively bred rat lines. Alcohol Clin Exp Res 2005; 28:1796-804. [PMID: 15608595 DOI: 10.1097/01.alc.0000148106.71801.d7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Genetic variance in initial sensitivity to ethanol has been implicated as a risk factor for the development of alcoholism. Identification of the genes that confer differential initial sensitivity is an important goal for the development of new treatment strategies and for a comprehensive understanding of the mechanism of ethanol's action. Quantitative trait loci (QTL) mapping for initial sensitivity and other ethanol-related behavioral traits in model organisms has become an important first step for the ultimate identification of genes that contribute to variation in ethanol responses. METHODS An F(2) intercross was made from the Inbred High and Low Alcohol Sensitivity rat lines (IHAS and ILAS). The F(2) rats were tested for duration of the loss of righting reflex test (LORR); blood ethanol concentration at regain of righting reflex (BECrrr); BEC at the first time to reach criterion on the rotarod after 1.6 g/kg of ethanol (BEC1); acute functional tolerance on the rotarod (AFT); and high-affinity neurotensin receptor (NTR1) density in the nucleus accumbens (NAc), caudate putamen (CP), and ventral midbrain (VMB). A full genome scan with an average marker spacing of 16.8 cM for interval QTL mapping was conducted on the F(2) rats (N = 363). RESULTS Seven significant or suggestive QTL were detected for LORR, one for BECrrr, three for BEC1, two for NTR1 binding in the CP, and one for binding in the NAc, but none were mapped for AFT or NTR1 binding density in the VMB. Effect size of the seven LORR QTL, the trait for which the parental strains were selected, ranged from 3 to 4%, with all accounting for approximately 22% of the total phenotypic variation. One of the LORR QTL on chromosome 2 (approximately 87 cM) was significant, and a second QTL on chromosome 5 (approximately 37 cM) was suggestive for both LORR and BECrrr. CONCLUSIONS The results indicate that segregating populations derived from the IHAS and ILAS strains can be used for mapping ethanol sensitivity QTL. The chromosome 2 LORR QTL may confer variation in ethanol metabolism, whereas the chromosome 5 LORR/BECrrr QTL likely mediates central nervous system ethanol sensitivity. The small number or absence of QTL for BEC1, AFT, and NTR1 receptor density suggests that genetic variation for these traits is minimal in the IHAS/ILAS strains and/or the effect size of QTL for these traits is too small to be mapped efficiently in this sample of F(2) rats. The ultimate identification of genes underlying these alcohol sensitivity QTL will contribute to our understanding of the actions of alcohol in the central nervous system if not to a deeper understanding of the genetic risk factors for alcoholism.
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Affiliation(s)
- Richard A Radcliffe
- University of Colorado Health Sciences Center, Department of Pharmaceutical Sciences, Campus Box C238, 4200 East Ninth Avenue, Denver, CO 80262, USA.
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Erwin VG, Gehle VM, Davidson K, Radcliffe RA. Confirmation of Correlations and Common Quantitative Trait Loci Between Neurotensin Receptor Density and Hypnotic Sensitivity to Ethanol. Alcohol Clin Exp Res 2001. [DOI: 10.1111/j.1530-0277.2001.tb02178.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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9
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Tajuddin NF, Druse MJ. Effects of Chronic Ethanol Consumption and Aging on Proenkephalin and Neurotensin. Alcohol Clin Exp Res 1998. [DOI: 10.1111/j.1530-0277.1998.tb03715.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Since its discovery in 1973, the neuropeptide neurotensin has been demonstrated to be involved in the control of a broad variety of physiological activities in both the central nervous system and in the periphery. Pharmacological studies have shown that the biological effects elicited by neurotensin result from its specific binding to cell membrane neurotensin receptors that have been characterized in various tissue and in cell preparations. In addition, it is now well documented that most of these responses are subject to rapid desensitization. Such desensitization results in transient responses to sustained peptide applications, or to tachyphylaxis during successive stimulations in the same conditions. More recently, desensitization of neurotensin signalling was investigated at the cellular and molecular levels. In cultured cells, regulation at the second messenger level, receptor internalization, and receptor down-regulation processes have been reported. These are proposed to play a critical role in the control of cell responsiveness to neurotensin. This review aims to compile recent data on the different biochemical processes involved in the regulation of the neurotensin receptor and to discuss the physiological consequences of this regulation in vivo.
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Affiliation(s)
- E Hermans
- Laboratory of Pharmacology, Université Catholique de Louvain, Brussels, Belgium
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Hammoumi S, Naassila M, Daoust M. Experimental findings in the study of the reduction of alcohol intake. Eur Neuropsychopharmacol 1997; 7 Suppl 3:S337-40. [PMID: 9405960 DOI: 10.1016/s0924-977x(97)00066-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Alcohol dependence represents a major problem in public health and different animal models of dependence have been developed in rodents with the aim of studying the mechanisms of alcohol abuse. Different ways of animal alcoholisation have been established. They permit a better understanding of which neurotransmitter system is involved in the regulation of alcohol dependence. Considerable attention has been given to the role of serotonin in the control of both alcohol craving and alcohol related pathologies, i.e. anxiety, aggression or memory loss. In conclusion, the use of animal models of alcohol abuse facilitates the understanding of alcohol behavior and permits the development of new therapeutic agents.
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Affiliation(s)
- S Hammoumi
- INSERM U295, Saint Etienne du Rouvray, France
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Banks WA, Wustrow DJ, Cody WL, Davis MD, Kastin AJ. Permeability of the blood-brain barrier to the neurotensin8-13 analog NT1. Brain Res 1995; 695:59-63. [PMID: 8574648 DOI: 10.1016/0006-8993(95)00836-f] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Neurotensin (NT) has been suggested to be a neuropeptide with therapeutic potential. We used multiple-time regression analysis to measure the unidirectional influx constant (Ki) of a tritiated analog of NT8-13, NT1, with improved metabolic stability. The Ki of [3H]NT1 across the blood-brain barrier (BBB) was 5.12(10(-4)) ml/g-min and was decreased 66% by unlabeled NT1 system. The amount of NT1 crossing the BBB, 0.087% of the injected dose per gram of brain, is consistent with its exerting central effects after peripheral administration. The stable [3H]NT1 crossed the BBB in intact form as assessed by HPLC and completely crossed the endothelial cells that comprise the BBB as assessed by the capillary depletion method. The presence of a transport system could be important for the development of NT analogs.
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Affiliation(s)
- W A Banks
- Veterans Affairs Medical Center, Tulane University School of Medicine, New Orleans, LA, USA
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13
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Erwin VG, Campbell AD, Myers R, Womer DE. Cross-tolerance between ethanol and neurotensin in mice selectively bred for ethanol sensitivity. Pharmacol Biochem Behav 1995; 51:891-9. [PMID: 7675874 DOI: 10.1016/0091-3057(95)00070-d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Neurotensin (NT), a tridecapeptide that satisfies criteria as a neurotransmitter, mimics many actions of ethanol, and evidence indicates that some of the acute effects of ethanol are mediated in part by NT. Recent studies have shown that chronic ethanol treatment produced a downregulation of NT receptors in mesolimbic brain regions of long sleep (LS) mice and that reduced NT binding capacity was associated with acquisition and decay of tolerance to ethanol-induced locomotor inhibition and hypothermia in these mice. The present study was undertaken to determine whether cross-tolerance develops between NT and ethanol and whether chronic NT infusion produces NT receptor downregulation. Animals chronically treated with ethanol were tolerant to NT-mediated locomotor inhibition at a dose of 1.8 pmol NT, ICV, and were tolerant to NT-induced hypothermia at 1.8 and 6.0 pmol NT. Following repeated injections or continuous infusion of NT ICV, LS mice showed tolerance to both NT- and ethanol-induced hypothermia and locomotor inhibition. Indeed, ethanol doses that are hypnotic in control mice (2.8 g/kg) were not effective in abolishing locomotor activity following chronic NT administration. Results with chronic saline infusion ICV indicate that stress alters sensitivity to ethanol-induced hypothermia. Chronic infusion of NT ICV produced a region-specific downregulation of high-affinity NT receptors in the striatum. The results demonstrate that cross-tolerance develops between NT and ethanol, and further support a role for neurotensinergic systems in the actions of ethanol.
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Affiliation(s)
- V G Erwin
- School of Pharmacy, University of Colorado Health Sciences Center, Denver 80262, USA
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Erwin VG, Jones BC, Myers R. Effects of acute and chronic ethanol administration on neurotensinergic systems. Ann N Y Acad Sci 1994; 739:185-96. [PMID: 7832472 DOI: 10.1111/j.1749-6632.1994.tb19820.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A summary of pharmacogenetic studies designed to test the hypothesis that NT receptors might mediate or regulate some of the actions of ethanol is presented. Indeed, there are significant genetic correlations between ethanol-induced locomotor activation and high-affinity NT receptor densities in the FC. The results suggest that further studies are needed to determine the role of NT receptors in the FC and MPFC in regulating locomotor activity. In other studies, chronic ethanol treatment, under conditions that produced tolerance to ethanol and caused NT receptor downregulation in the NA and VMB, caused tolerance to locomotor inhibitory effects of centrally administered NT and blunted the effects of intra-VTA NT on dopamine metabolism in the NA and CP. The results show a relationship between NT receptor densities and pharmacological effects of ethanol.
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Affiliation(s)
- V G Erwin
- Alcohol Research Center, School of Pharmacy, University of Colorado Health Sciences Center, Denver 80262
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