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Kanarik M, Liiver K, Norden M, Teino I, Org T, Laugus K, Shimmo R, Karelson M, Saarma M, Harro J. RNA m 6A methyltransferase activator affects anxiety-related behaviours, monoamines and striatal gene expression in the rat. Acta Neuropsychiatr 2024:1-16. [PMID: 39380240 DOI: 10.1017/neu.2024.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/10/2024]
Abstract
Modification of mRNA by methylation is involved in post-transcriptional regulation of gene expression by affecting the splicing, transport, stability and translation of mRNA. Methylation of adenosine at N6 (m6A) is one of the most common and important cellular modification occurring in the mRNA of eukaryotes. Evidence that m6A mRNA methylation is involved in regulation of stress response and that its dysregulation may contribute to the pathogenesis of neuropsychiatric disorders is accumulating. We have examined the acute and subchronic (up to 18 days once per day intraperitoneally) effect of the first METTL3/METTL14 activator compound CHMA1004 (methyl-piperazine-2-carboxylate) at two doses (1 and 5 mg/kg) in male and female rats. CHMA1004 had a locomotor activating and anxiolytic-like profile in open field and elevated zero-maze tests. In female rats sucrose consumption and swimming in Porsolt's test were increased. Nevertheless, CHMA1004 did not exhibit strong psychostimulant-like properties: CHMA1004 had no effect on 50-kHz ultrasonic vocalizations except that it reduced the baseline difference between male and female animals, and acute drug treatment had no effect on extracellular dopamine levels in striatum. Subchronic CHMA1004 altered ex vivo catecholamine levels in several brain regions. RNA sequencing of female rat striata after subchronic CHMA1004 treatment revealed changes in the expression of a number of genes linked to dopamine neuron viability, neurodegeneration, depression, anxiety and stress response. Conclusively, the first-in-class METTL3/METTL14 activator compound CHMA1004 increased locomotor activity and elicited anxiolytic-like effects after systemic administration, demonstrating that pharmacological activation of RNA m6A methylation has potential for neuropsychiatric drug development.
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Affiliation(s)
- Margus Kanarik
- Division of Neuropsychopharmacology, Institute of Chemistry, University of Tartu, Tartu, Tartumaa, Estonia
| | - Kristi Liiver
- School of Natural Sciences and Health, Tallinn University, Tallinn, Harjumaa, Estonia
| | - Marianna Norden
- School of Natural Sciences and Health, Tallinn University, Tallinn, Harjumaa, Estonia
- Institute of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia
| | - Indrek Teino
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Uusimaa, Finland
- Institute of Molecular and Cell Biology, University of Tartu, Tartu, Tartumaa, Estonia
| | - Tõnis Org
- Institute of Genomics, University of Tartu, Tartu, Tartumaa, Estonia
| | - Karita Laugus
- Division of Neuropsychopharmacology, Institute of Chemistry, University of Tartu, Tartu, Tartumaa, Estonia
| | - Ruth Shimmo
- School of Natural Sciences and Health, Tallinn University, Tallinn, Harjumaa, Estonia
| | - Mati Karelson
- Division of Molecular Technology, Institute of Chemistry, University of Tartu, Tartu, Estonia
| | - Mart Saarma
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Uusimaa, Finland
| | - Jaanus Harro
- Division of Neuropsychopharmacology, Institute of Chemistry, University of Tartu, Tartu, Tartumaa, Estonia
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Uusimaa, Finland
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Kahnau P, Mieske P, Wilzopolski J, Kalliokoski O, Mandillo S, Hölter SM, Voikar V, Amfim A, Badurek S, Bartelik A, Caruso A, Čater M, Ey E, Golini E, Jaap A, Hrncic D, Kiryk A, Lang B, Loncarevic-Vasiljkovic N, Meziane H, Radzevičienė A, Rivalan M, Scattoni ML, Torquet N, Trifkovic J, Ulfhake B, Thöne-Reineke C, Diederich K, Lewejohann L, Hohlbaum K. A systematic review of the development and application of home cage monitoring in laboratory mice and rats. BMC Biol 2023; 21:256. [PMID: 37953247 PMCID: PMC10642068 DOI: 10.1186/s12915-023-01751-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 10/30/2023] [Indexed: 11/14/2023] Open
Abstract
BACKGROUND Traditionally, in biomedical animal research, laboratory rodents are individually examined in test apparatuses outside of their home cages at selected time points. However, the outcome of such tests can be influenced by various factors and valuable information may be missed when the animals are only monitored for short periods. These issues can be overcome by longitudinally monitoring mice and rats in their home cages. To shed light on the development of home cage monitoring (HCM) and the current state-of-the-art, a systematic review was carried out on 521 publications retrieved through PubMed and Web of Science. RESULTS Both the absolute (~ × 26) and relative (~ × 7) number of HCM-related publications increased from 1974 to 2020. There was a clear bias towards males and individually housed animals, but during the past decade (2011-2020), an increasing number of studies used both sexes and group housing. In most studies, animals were kept for short (up to 4 weeks) time periods in the HCM systems; intermediate time periods (4-12 weeks) increased in frequency in the years between 2011 and 2020. Before the 2000s, HCM techniques were predominantly applied for less than 12 h, while 24-h measurements have been more frequent since the 2000s. The systematic review demonstrated that manual monitoring is decreasing in relation to automatic techniques but still relevant. Until (and including) the 1990s, most techniques were applied manually but have been progressively replaced by automation since the 2000s. Independent of the year of publication, the main behavioral parameters measured were locomotor activity, feeding, and social behaviors; the main physiological parameters were heart rate and electrocardiography. External appearance-related parameters were rarely examined in the home cages. Due to technological progress and application of artificial intelligence, more refined and detailed behavioral parameters have been investigated in the home cage more recently. CONCLUSIONS Over the period covered in this study, techniques for HCM of mice and rats have improved considerably. This development is ongoing and further progress as well as validation of HCM systems will extend the applications to allow for continuous, longitudinal, non-invasive monitoring of an increasing range of parameters in group-housed small rodents in their home cages.
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Affiliation(s)
- Pia Kahnau
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Berlin, Germany
| | - Paul Mieske
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Berlin, Germany
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Marchstr. 23, 10587, Berlin, Germany
| | - Jenny Wilzopolski
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Berlin, Germany
| | - Otto Kalliokoski
- Department of Experimental Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Silvia Mandillo
- Institute of Biochemistry and Cell Biology, National Research Council CNR, Rome, Italy
| | - Sabine M Hölter
- Helmholtz Zentrum München, German Research Centre for Environmental Health, Munich, Germany
| | - Vootele Voikar
- Neuroscience Center, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, Helsinki, Finland
| | - Adriana Amfim
- Faculty of Veterinary Medicine, Spiru Haret University, Bucharest, Romania
| | - Sylvia Badurek
- Preclinical Phenotyping Facility, Vienna Biocenter Core Facilities (VBCF), member of the Vienna Biocenter (VBC), Vienna, Austria
| | - Aleksandra Bartelik
- International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Angela Caruso
- Istituto Superiore Di Sanità, Research Coordination and Support Service, Rome, Italy
| | - Maša Čater
- Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Elodie Ey
- Université de Strasbourg, CNRS, Inserm, Institut de Génétique et de Biologie Moléculaire et Cellulaire UMR 7104- UMR-S 1258, Illkirch, 67400, France
| | - Elisabetta Golini
- Institute of Biochemistry and Cell Biology, National Research Council CNR, Rome, Italy
| | - Anne Jaap
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Marchstr. 23, 10587, Berlin, Germany
| | - Dragan Hrncic
- Institute of Medical Physiology "Richard Burian", Faculty of Medicine, University of Belgrade, Belgrade, Serbia
| | - Anna Kiryk
- Laboratory of Preclinical Testing of Higher Standard, Neurobiology Center, Nencki Institute of Experimental Biology, Polish Academy of Science, Warsaw, Poland
| | - Benjamin Lang
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Marchstr. 23, 10587, Berlin, Germany
| | - Natasa Loncarevic-Vasiljkovic
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Hamid Meziane
- Université de Strasbourg, CNRS, INSERM, Institut Clinique de La Souris (ICS), CELPHEDIA, PHENOMIN, 1 Rue Laurent Fries, Illkirch, 67404, France
| | - Aurelija Radzevičienė
- Lithuanian University of Health Sciences, Medical Academy, Institute of Physiology and Pharmacology, Kaunas, Lithuania
| | - Marion Rivalan
- Research Institute for Experimental Medicine (FEM) and NeuroCure Cluster of Excellence, Animal Behaviour Phenotyping Facility, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Maria Luisa Scattoni
- Istituto Superiore Di Sanità, Research Coordination and Support Service, Rome, Italy
| | - Nicolas Torquet
- Université de Strasbourg, CNRS, Inserm, IGBMC, Institut Clinique de la Souris (ICS), CELPHEDIA, PHENOMIN, UMR 7104- UMR-S 1258, Illkirch, 67400, France
| | - Julijana Trifkovic
- Department of Veterinary Medicine, Faculty of Agriculture, University of East Sarajevo, East Sarajevo, Bosnia and Herzegovina
| | - Brun Ulfhake
- Div. Clinical Physiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Christa Thöne-Reineke
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Marchstr. 23, 10587, Berlin, Germany
| | - Kai Diederich
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Berlin, Germany
| | - Lars Lewejohann
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Berlin, Germany
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Science of Intelligence, Research Cluster of Excellence, Marchstr. 23, 10587, Berlin, Germany
| | - Katharina Hohlbaum
- German Federal Institute for Risk Assessment (BfR), German Centre for the Protection of Laboratory Animals (Bf3R), Berlin, Germany.
- Science of Intelligence, Research Cluster of Excellence, Marchstr. 23, 10587, Berlin, Germany.
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Effect of Neuropeptide S Administration on Ultrasonic Vocalizations and Behaviour in Rats with Low vs. High Exploratory Activity. Pharmaceuticals (Basel) 2021; 14:ph14060524. [PMID: 34070724 PMCID: PMC8229755 DOI: 10.3390/ph14060524] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 12/20/2022] Open
Abstract
Neuropeptide S (NPS) is a peptide neurotransmitter that in animal studies promotes wakefulness and arousal with simultaneous anxiety reduction, in some inconsistency with results in humans. We examined the effect of NPS on rat ultrasonic vocalizations (USV) as an index of affective state and on behaviour in novel environments in rats with persistent inter-individual differences in exploratory activity. Adult male Wistar rats were categorised as of high (HE) or low (LE) exploratory activity and NPS was administered intracerebroventricularly (i.c.v.) at a dose of 1.0 nmol/5 µL, after which USVs were recorded in the home-cage and a novel standard housing cage, and behaviour evaluated in exploration/anxiety tests. NPS induced a massive production of long and short 22 kHz USVs in the home cage that continued later in the novel environment; no effect on 50 kHz USVs were found. In LE-rats, the long 22 kHz calls were emitted at lower frequencies and were louder. The effects of NPS on behaviour appeared novelty- and test-dependent. NPS had an anxiolytic-like effect in LE-rats only in the elevated zero-maze, whereas in HE-rats, locomotor activity in the zero-maze and in a novel standard cage was increased. Thus NPS appears as a psychostimulant peptide but with a complex effect on dimensions of affect.
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Kõiv K, Vares M, Kroon C, Metelitsa M, Tiitsaar K, Laugus K, Jaako K, Harro J. Effect of chronic variable stress on sensitization to amphetamine in high and low sucrose-consuming rats. J Psychopharmacol 2019; 33:1512-1523. [PMID: 31208275 DOI: 10.1177/0269881119856000] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Individual vulnerability to stress manifests in the interaction of innate properties and environment. There is a growing interest in the individual variability in vulnerability to stress and how it contributes to the development of psychiatric disorders. Intake of palatable substances is often measured in animal models. We have previously demonstrated that the consumption of sucrose solution is a stable trait in rats. AIMS The present study aimed to compare the sensitivity of rats with high vs low liquid sucrose consumption to chronic variable stress and the stress effect on behavioural sensitization to amphetamine. METHODS Male Wistar rats were subjected to a chronic stress regimen and subsequent repeated treatment with amphetamine (1 mg/kg, intraperitoneally). Fifty-kHz ultrasonic vocalizations, locomotor activity and stereotypies were measured. RESULTS In no-stress baseline conditions, the behavioural response to acute amphetamine was similar in rats with high vs low sucrose consumption. Prior chronic stress potentiated the effect of amphetamine only in rats with high sucrose consumption. Behavioural sensitization to repeated administration of amphetamine was observed in non-stressed rats with lower sucrose preference, but not in the respective stressed group that had increased monoamine turnover in the nucleus accumbens. In contrast, in rats with high sucrose preference the amphetamine sensitization effect was prevalent in stressed rats, but not in non-stressed animals. INTERPRETATION Chronic stress can change the psychostimulant effect but this depends on the inherent reward sensitivity of the animal. Trait-wise, sucrose intake reflects vulnerability to chronic stress and may interact with the development of addiction.
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Affiliation(s)
- Kadri Kõiv
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Marten Vares
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Cristina Kroon
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Mait Metelitsa
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Kai Tiitsaar
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Karita Laugus
- Department of Psychology, University of Tartu, Tartu, Estonia
| | - Külli Jaako
- Department of Pharmacology, University of Tartu, Tartu, Estonia
| | - Jaanus Harro
- Department of Psychology, University of Tartu, Tartu, Estonia
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Animals, anxiety, and anxiety disorders: How to measure anxiety in rodents and why. Behav Brain Res 2018; 352:81-93. [DOI: 10.1016/j.bbr.2017.10.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 10/12/2017] [Accepted: 10/14/2017] [Indexed: 12/31/2022]
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Ballaz S. The unappreciated roles of the cholecystokinin receptor CCK(1) in brain functioning. Rev Neurosci 2017; 28:573-585. [DOI: 10.1515/revneuro-2016-0088] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/05/2017] [Indexed: 12/13/2022]
Abstract
AbstractThe CCK(1) receptor is a G-protein-coupled receptor activated by the sulfated forms of cholecystokinin (CCK), a gastrin-like peptide released in the gastrointestinal tract and mammal brain. A substantial body of research supports the hypothesis that CCK(1)r stimulates gallbladder contraction and pancreatic secretion in the gut, as well as satiety in brain. However, this receptor may also fulfill relevant roles in behavior, thanks to its widespread distribution in the brain. The strategic location of CCK(1)r in mesolimbic structures and specific hypothalamic and brainstem nuclei lead to complex interactions with neurotransmitters like dopamine, serotonin, and glutamate, as well as hypothalamic hormones and neuropeptides. The activity of CCK(1)r maintains adequate levels of dopamine and regulates the activity of serotonin neurons of raphe nuclei, which makes CCK(1)r an interesting therapeutic target for the development of adjuvant treatments for schizophrenia, drug addiction, and mood disorders. Unexplored functions of CCK(1)r, like the transmission of interoceptive sensitivity in addition to the regulation of hypothalamic hormones and neurotransmitters affecting emotional states, well-being, and attachment behaviors, may open exciting roads of research. The absence of specific ligands for the CCK(1) receptor has complicated the study of its distribution in brain so that research about its impact on behavior has been published sporadically over the last 30 years. The present review reunites all this body of evidence in a comprehensive way to summarize our knowledge about the actual role of CCK in the neurobiology of mental illness.
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Affiliation(s)
- Santiago Ballaz
- School of Biological Sciences and Engineering, Yachay Tech University, Hacienda San Jose y Proyecto Yachay s/n, San Miguel de Urcuquí 100119, Ecuador
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Middle-range exploratory activity in adult rats suggests higher resilience to chronic social defeat. Acta Neuropsychiatr 2016; 28:125-40. [PMID: 26669552 DOI: 10.1017/neu.2015.64] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Stressful life events play an important role in the aetiology of human mood disorders and are frequently modelled by chronic social defeat (SD) in rodents. Exploratory phenotype in rats is a stable trait that is likely related to inter-individual differences in reactivity to stress. The aim of the study was to confirm that low levels of exploratory activity (LE) are, in rodents, a risk factor for passive stress coping, and to clarify the role of medium (ME) and high (HE) exploratory disposition in the sensitivity to SD. METHODS We examined the effect of SD on male Wistar rats with LE, ME, and HE activity levels as measured in the exploration box. After SD, the rats were evaluated in social preference, elevated zero maze, and open-field tests. Brain tissue levels of monoamines were measured by high-performance liquid chromatography. RESULTS Rats submitted to SD exhibited lower weight gain, higher sucrose consumption, showed larger stress-induced hyperthermia, lower levels of homovanillic acid in the frontal cortex, and higher levels of noradrenaline in the amygdala and hippocampus. Open-field, elevated zero maze, and social preference tests revealed the interaction between stress and phenotype, as only LE-rats were further inhibited by SD. ME-rats exhibited the least reactivity to stress in terms of changes in body weight, stress-induced hyperthermia, and sucrose intake. CONCLUSION Both low and high novelty-related activity, especially the former, are associated with elevated sensitivity to social stress. This study shows that both tails of a behavioural dimension can produce stress-related vulnerability.
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Bowers ME, Ressler KJ. Interaction between the cholecystokinin and endogenous cannabinoid systems in cued fear expression and extinction retention. Neuropsychopharmacology 2015; 40:688-700. [PMID: 25176168 PMCID: PMC4289957 DOI: 10.1038/npp.2014.225] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 07/10/2014] [Accepted: 08/02/2014] [Indexed: 01/29/2023]
Abstract
Post-traumatic stress disorder (PTSD) is thought to develop, in part, from improper inhibition of fear. Accordingly, one of the most effective treatment strategies for PTSD is exposure-based psychotherapy. Ideally, neuroscience would inform adjunct therapies that target the neurotransmitter systems involved in extinction processes. Separate studies have implicated the cholecystokinin (CCK) and endocannabinoid systems in fear; however, there is a high degree of anatomical colocalization between the cannabinoid 1 receptor (Cnr1) and CCK in the basolateral amygdala (BLA), a brain region critical for emotion regulation. Although most research has focused on GABA and GABAergic plasticity as the mechanism by which Cnr1 mediates fear inhibition, we hypothesize that a functional interaction between Cnr1 and CCKB receptor (CCKBR) is critical for fear extinction processes. In this study, systemic pharmacological manipulation of the cannabinoid system modulated cued fear expression in C57BL/6J mice after consolidation of auditory fear conditioning. Knockout of the CCKBR, however, had no effect on fear- or anxiety-like behaviors. Nonetheless, administration of a Cnr1 antagonist increased freezing behavior during a cued fear expression test in wild-type subjects, but had no effect on freezing behavior in CCKBR knockout littermates. In addition, we found that Cnr1-positive fibers form perisomatic clusters around CCKBR-positive cell bodies in the BLA. These CCKBR-positive cells comprise a molecularly heterogenous population of excitatory and inhibitory neurons. These findings provide novel evidence that Cnr1 contributes to cued fear expression via an interaction with the CCK system. Dysfunctional Cnr1-CCKBR interactions might contribute to the etiology of, or result from, fear-related psychiatric disease.
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Affiliation(s)
- Mallory E Bowers
- Behavioral Neuroscience, Department of Psychiatry and Behavioral Sciences, Howard Hughes Medical Institute, Emory University, Yerkes Research Center, Atlanta, GA, USA
| | - Kerry J Ressler
- Behavioral Neuroscience, Department of Psychiatry and Behavioral Sciences, Howard Hughes Medical Institute, Emory University, Yerkes Research Center, Atlanta, GA, USA,Howard Hughes Medical Institute, Emory University, Atlanta, GA, USA,Behavioral Neuroscience, Department of Psychiatry and Behavioral Sciences, Howard Hughes Medical Institute, Emory University, Yerkes Research Center, 954 Gatewood Dr, NE Atlanta, GA 30329, USA, Tel: +1 404 727 7739, Fax: +1 404 727 8070, E-mail:
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Desai SJ, Borkar CD, Nakhate KT, Subhedar NK, Kokare DM. Neuropeptide Y attenuates anxiety- and depression-like effects of cholecystokinin-4 in mice. Neuroscience 2014; 277:818-30. [PMID: 25106129 DOI: 10.1016/j.neuroscience.2014.07.062] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 07/02/2014] [Accepted: 07/28/2014] [Indexed: 01/08/2023]
Abstract
We investigated the involvement of neuropeptide Y (NPY) in the modulation of cholecystokinin-4 (CCK-4)-evoked anxiety and depression. Adult male mice were injected with vehicle, CCK-4, NPY, NPY Y1 receptor agonist [Leu(31), Pro(34)]-NPY or antagonist BIBP3226, via intracerebroventricular route, and subjected to social interaction or forced swim test (FST) for the evaluation of anxiety- and depression-like phenotypes, respectively. To assess the interactions between the two systems, if any, NPYergic agents were administered prior to CCK-4 and the animals were subjected to these behavioral tests. Treatment with CCK-4 or BIBP3226 dose-dependently reduced social interaction time, while NPY or [Leu(31), Pro(34)]-NPY produced opposite effect. CCK-4 treatment increased immobility time in FST. This effect was reversed by NPY and [Leu(31), Pro(34)]-NPY, although BIBP3226 per se did not alter the immobility time. In a combination study, the anxiogenic or depressive effects of CCK-4 were attenuated by NPY or [Leu(31), Pro(34)]-NPY and potentiated by BIBP3226. The brains of CCK-4 treated rats were processed for NPY immunohistochemistry. Following CCK-4 treatment, the nucleus accumbens shell (AcbSh), ventral part of lateral division of the bed nucleus of stria terminalis (BSTLV), hypothalamic paraventricular nucleus and locus coeruleus showed a reduction in NPY-immunoreactive fibers. Population of NPY-immunopositive cells was also decreased in the AcbSh, BSTLV, prefrontal cortex and hypothalamic arcuate nucleus (ARC). However, NPY-immunoreaction in the fibers of the ARC and cells of the central nucleus of amygdala was unchanged. We conclude that, inhibition of NPY signaling in the brain by CCK-4 might be causal to anxiety- and depression-like behaviors.
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Affiliation(s)
- S J Desai
- Department of Anatomy & Cell Biology, University of Western Ontario, Ontario, Canada
| | - C D Borkar
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440 033, Maharashtra, India
| | - K T Nakhate
- Rungta College of Pharmaceutical Sciences and Research, Rungta Educational Campus, Kohka-Kurud Road, Bhilai 490 024, Chhattisgarh, India
| | - N K Subhedar
- Indian Institute of Science Education and Research (IISER), Central Tower, Sai Trinity Building, Garware Circle, Sutarwadi, Pashan, Pune 411 021, Maharashtra, India
| | - D M Kokare
- Department of Pharmaceutical Sciences, Rashtrasant Tukadoji Maharaj Nagpur University, Nagpur 440 033, Maharashtra, India.
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Bell R, Duke AA, Gilmore PE, Page D, Bègue L. Anxiolytic-like effects observed in rats exposed to the elevated zero-maze following treatment with 5-HT2/5-HT3/5-HT4 ligands. Sci Rep 2014; 4:3881. [PMID: 24457553 PMCID: PMC5379192 DOI: 10.1038/srep03881] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Accepted: 01/08/2014] [Indexed: 01/06/2023] Open
Abstract
The present study examined the effects of administering selective 5-HT antagonists and agonists to rats tested in the elevated zero-maze (EZM) model of anxiety. The EZM paradigm has advantages over the elevated plus-maze (EPM) paradigm with respect to measuring anxiety, yet has been utilized less frequently. Three experiments were conducted each with a diazepam control (0.25, 0.5 and 0.75 mg/kg). In the first experiment, we administered the 5-HT2C antagonist RS 102221 (0.5, 1.0, and 2.0 mg/kg) and 5-HT2C agonist MK-212 (0.25, 0.5 and 0.75 mg/kg); in the second experiment, we administered the 5-HT3 antagonist Y-25130 (0.1, 1.0 and 3.0 mg/kg) and 5-HT3 agonist SR 57227A (0.1, 1.0 and 3.0 mg/kg), and in the third experiment, we administered the 5-HT4 antagonist RS 39604 (0.01, 0.1, 1.0 mg/kg) and 5-HT4 agonist RS 67333 (0.01, 0.1 and 0.5 mg/kg). The administration of 5-HT2/3/4 subtype antagonists all generated behavioral profiles indicative of anxiolytic-like effects in the EZM, which was apparent from examination of both traditional and ethological measures. While little effect was observed from 5-HT2 and 5-HT3 agonists, the 5-HT4 agonist RS 67333 was found to produce a paradoxical anxiolytic-like effect similar to that produced by the 5-HT4 antagonist RS 39604. We conclude by discussing the implications of these findings.
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Affiliation(s)
- Rob Bell
- School of Psychology, Queen's University, Belfast, Northern Ireland, UK
| | - Aaron A. Duke
- Department of Psychology, University of Kentucky, USA
- Department of Psychology, Grenoble-Alpes University, France
| | - Paula E. Gilmore
- School of Psychology, Queen's University, Belfast, Northern Ireland, UK
| | - Deaglan Page
- School of Psychology, Queen's University, Belfast, Northern Ireland, UK
| | - Laurent Bègue
- Department of Psychology, Grenoble-Alpes University, France
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Li X, Yu K, Zhang Z, Sun W, Yang Z, Feng J, Chen X, Liu CH, Wang H, Guo YP, He J. Cholecystokinin from the entorhinal cortex enables neural plasticity in the auditory cortex. Cell Res 2013; 24:307-30. [PMID: 24343575 PMCID: PMC3945883 DOI: 10.1038/cr.2013.164] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 10/03/2013] [Accepted: 11/12/2013] [Indexed: 01/12/2023] Open
Abstract
Patients with damage to the medial temporal lobe show deficits in forming new declarative memories but can still recall older memories, suggesting that the medial temporal lobe is necessary for encoding memories in the neocortex. Here, we found that cortical projection neurons in the perirhinal and entorhinal cortices were mostly immunopositive for cholecystokinin (CCK). Local infusion of CCK in the auditory cortex of anesthetized rats induced plastic changes that enabled cortical neurons to potentiate their responses or to start responding to an auditory stimulus that was paired with a tone that robustly triggered action potentials. CCK infusion also enabled auditory neurons to start responding to a light stimulus that was paired with a noise burst. In vivo intracellular recordings in the auditory cortex showed that synaptic strength was potentiated after two pairings of presynaptic and postsynaptic activity in the presence of CCK. Infusion of a CCKB antagonist in the auditory cortex prevented the formation of a visuo-auditory association in awake rats. Finally, activation of the entorhinal cortex potentiated neuronal responses in the auditory cortex, which was suppressed by infusion of a CCKB antagonist. Together, these findings suggest that the medial temporal lobe influences neocortical plasticity via CCK-positive cortical projection neurons in the entorhinal cortex.
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Affiliation(s)
- Xiao Li
- 1] Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China [2] University of Chinese Academy of Sciences (CAS) and CAS-Hong Kong Joint Laboratory, Institute of Biophysics, Beijing 100101, China [3] University of Chinese Academy of Sciences (CAS) and CAS-Hong Kong Joint Laboratory, Institute of Biophysics, Beijing 100101, China
| | - Kai Yu
- 1] Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong [2] Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Zicong Zhang
- 1] Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China [2] Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Wenjian Sun
- 1] Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China [2] Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Zhou Yang
- 1] Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong [2] Division of Life Science, Hong Kong University of Science and Technology, Clearwater Bay, N.T., Hong Kong SAR, China
| | - Jingyu Feng
- 1] Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China [2] Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Xi Chen
- 1] Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China [2] Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
| | - Chun-Hua Liu
- 1] Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China [2] Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou, Guangdong 510530, China
| | - Haitao Wang
- 1] Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China [2] Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou, Guangdong 510530, China
| | - Yi Ping Guo
- 1] Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China [2] Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou, Guangdong 510530, China
| | - Jufang He
- 1] Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China [2] University of Chinese Academy of Sciences (CAS) and CAS-Hong Kong Joint Laboratory, Institute of Biophysics, Beijing 100101, China [3] University of Chinese Academy of Sciences (CAS) and CAS-Hong Kong Joint Laboratory, Institute of Biophysics, Beijing 100101, China [4] Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, Guangdong 510530, China [5] Guangdong Provincial Key Laboratory of Stem Cell and Regenerative Medicine, Guangzhou, Guangdong 510530, China
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Zwanzger P, Domschke K, Bradwejn J. Neuronal network of panic disorder: the role of the neuropeptide cholecystokinin. Depress Anxiety 2012; 29:762-74. [PMID: 22553078 DOI: 10.1002/da.21919] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 01/09/2012] [Accepted: 01/13/2012] [Indexed: 11/08/2022] Open
Abstract
Panic disorder (PD) is characterized by panic attacks, anticipatory anxiety and avoidance behavior. Its pathogenesis is complex and includes both neurobiological and psychological factors. With regard to neurobiological underpinnings, anxiety in humans seems to be mediated through a neuronal network, which involves several distinct brain regions, neuronal circuits and projections as well as neurotransmitters. A large body of evidence suggests that the neuropeptide cholecystokinin (CCK) might be an important modulator of this neuronal network. Key regions of the fear network, such as amygdala, hypothalamus, peraqueductal grey, or cortical regions seem to be connected by CCKergic pathways. CCK interacts with several anxiety-relevant neurotransmitters such as the serotonergic, GABA-ergic and noradrenergic system as well as with endocannabinoids, NPY and NPS. In humans, administration of CCK-4 reliably provokes panic attacks, which can be blocked by antipanic medication. Also, there is some support for a role of the CCK system in the genetic pathomechanism of PD with particularly strong evidence for the CCK gene itself and the CCK-2R (CCKBR) gene. Thus, it is hypothesized that genetic variants in the CCK system might contribute to the biological basis for the postulated CCK dysfunction in the fear network underlying PD. Taken together, a large body of evidence suggests a possible role for the neuropeptide CCK in PD with regard to neuroanatomical circuits, neurotransmitters and genetic factors. This review article proposes an extended hypothetical model for human PD, which integrates preclinical and clinical findings on CCK in addition to existing theories of the pathogenesis of PD.
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Affiliation(s)
- P Zwanzger
- Mood and Anxiety Disorders Research Unit, Department of Psychiatry and Psychotherapy, University of Muenster, Muenster, Germany.
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13
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Flanigan TJ, Cook MN. Effects of an early handling-like procedure and individual housing on anxiety-like behavior in adult C57BL/6J and DBA/2J mice. PLoS One 2011; 6:e19058. [PMID: 21533042 PMCID: PMC3080884 DOI: 10.1371/journal.pone.0019058] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 03/23/2011] [Indexed: 11/18/2022] Open
Abstract
Manipulations of rearing conditions have been used to examine the effects of early experience on adult behavior with varying results. Evidence suggests that postnatal days (PND) 15-21 are a time of particular susceptibility to environmental influences on anxiety-like behavior in mice. To examine this, we subjected C57BL/6J and DBA/2J mice to an early handling-like procedure. Pups were separated from dams from PND 12-20 for 30 minutes daily or received standard care. On PND 21, pups were weaned and either individually- or group-housed. On PND 60, anxiety-like behavior was examined on the elevated zero-maze. Although individually-housed animals took longer to enter an open quadrant of the maze, they spent more time in the open than group-housed animals. Additionally, we observed a trend of reduced anxiety-like behavior in C57BL/6J, but not DBA/2J mice that underwent the handling-like procedure.
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Affiliation(s)
- Timothy J. Flanigan
- Department of Psychology, University of Memphis, Memphis, Tennessee, United States of America
| | - Melloni N. Cook
- Department of Psychology, University of Memphis, Memphis, Tennessee, United States of America
- * E-mail:
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Ballaz SJ, Akil H, Watson SJ. The CCK-system underpins novelty-seeking behavior in the rat: gene expression and pharmacological analyses. Neuropeptides 2008; 42:245-53. [PMID: 18410964 PMCID: PMC2706500 DOI: 10.1016/j.npep.2008.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2007] [Revised: 02/13/2008] [Accepted: 03/05/2008] [Indexed: 10/22/2022]
Abstract
Cholecystokinin (CCK) and its receptor CCK-2R have been shown to promote emotional responsivity and behavioral sensitization to psychostimulants in the rat. An animal model has been developed based on locomotor response to a novel inescapable environment. Animals exhibiting consistent differences in locomotor response to novelty have been termed as high and low responder rats (HR and LR, respectively). This paradigm is deemed to model sensation-seeking, a personality trait closely associated with substance abuse. The present study provides genetic and pharmacological evidence that the CCK-ergic system modulates this behavior. Distinctive patterns of CCK-related gene expression in HR and LR animals occurred beyond the mesolimbic pathways. CCK gene expression was higher in hippocampus, amygdala, and prefrontal cortex, but lower in the ventral tegmental area of HR relative to LR rats. Levels of CCK-2R mRNA were more elevated in LR animals in some areas of the forebrain such as the prefrontal cortex, nucleus accumbens, and hippocampus. Additionally, CCK-2R blockade with the antagonist LY225.910 (0.5 mg/kg) removed phenotype differences in sustained exploration of novel stimuli (i.e., a novel-object) in HR and LR rats exposed to an enriched open-field test series. Finally, CCK-2R blockade also altered M(2) and 5-HT(7) receptor gene expression in the mediodorsal thalamus (a strategic structure for corticothalamic trafficking) in a phenotype-dependent manner. Taken together, the findings reported here suggest that distinct CCK-ergic function may contribute to promoting individual differences in novelty-seeking behavior.
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Affiliation(s)
- Santiago J Ballaz
- iMed UL, Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal.
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15
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Karson MA, Whittington KC, Alger BE. Cholecystokinin inhibits endocannabinoid-sensitive hippocampal IPSPs and stimulates others. Neuropharmacology 2008; 54:117-28. [PMID: 17689570 PMCID: PMC2242378 DOI: 10.1016/j.neuropharm.2007.06.023] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 05/23/2007] [Accepted: 06/14/2007] [Indexed: 01/07/2023]
Abstract
Cholecystokinin (CCK) is the most abundant neuropeptide in the central nervous system. In the hippocampal CA1 region, CCK is co-localized with GABA in a subset of interneurons that synapse on pyramidal cell somata and apical dendrites. CCK-containing interneurons also uniquely express a high level of the cannabinoid receptor, CB(1), and mediate the retrograde signaling process called DSI. Reported effects of CCK on inhibitory post-synaptic potentials (IPSPs) in hippocampus are inconsistent, and include both increases and decreases in activity. Hippocampal interneurons are very heterogeneous, and these results could be reconciled if CCK affected different interneurons in different ways. To test this prediction, we used sharp microelectrode recordings from pyramidal cells with ionotropic glutamate receptors blocked, and investigated the effects of CCK on pharmacologically distinct groups of IPSPs during long-term recordings. We find that CCK, acting via the CCK(2) receptor, increases some IPSPs and decreases others, and most significantly, that the affected IPSPs can be classified into two groups by their pharmacological properties. IPSPs that are increased by carbachol (CCh-sIPSPs), are depressed by CCK, omega-conotoxin GVIA, and endocannabinoids. IPSPs that are enhanced by CCK (CCK-sIPSPs) are blocked by omega-agatoxin IVA, and are unaffected by carbachol or endocannabinoids. Interestingly, a CCK(2) antagonist enhances CCh-sIPSPs, suggesting normally they may be partially suppressed by endogenous CCK. In summary, our data are compatible with the hypothesis that CCK has opposite actions on sIPSPs that originate from functionally distinct interneurons.
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Affiliation(s)
- Miranda A Karson
- Department of Physiology, Program in Neuroscience, University of Maryland School of Medicine, 655 W. Baltimore Street, Baltimore, MD 21201, USA
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16
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Chung L, Moore SD. Cholecystokinin enhances GABAergic inhibitory transmission in basolateral amygdala. Neuropeptides 2007; 41:453-63. [PMID: 17904218 DOI: 10.1016/j.npep.2007.08.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Revised: 07/13/2007] [Accepted: 08/11/2007] [Indexed: 11/25/2022]
Abstract
The neuropeptide cholecystokinin (CCK) is anxiogenic in studies of human and animal behavior. As the amygdala formation has been implicated in generation of emotional states such as anxiety, we tested the effect of CCK on spontaneous synaptic events in the basolateral amygdala (BLA) using whole cell patch recordings in rat brain slice preparation. We found that CCK increased the frequency of spontaneous inhibitory postsynaptic potentials (sIPSPs) and currents (sIPSCs). This effect was blocked by the fast sodium channel blocker tetrodotoxin (TTX), indicating that the CCK effect is likely mediated by direct excitation of GABAergic interneurons. The CCK(B) receptor subtype antagonist, CR2945, blocked the CCK effect, while CCK4, a specific CCK(B) agonist, increased sIPSC frequency. We hypothesize that these actions may underlie the anxiogenic effects of CCK observed in behavioral studies.
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Affiliation(s)
- L Chung
- Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, USA
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17
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Harro J. CCK and NPY as anti-anxiety treatment targets: promises, pitfalls, and strategies. Amino Acids 2006; 31:215-30. [PMID: 16738800 DOI: 10.1007/s00726-006-0334-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 03/06/2006] [Indexed: 11/26/2022]
Abstract
Short CCK peptides elicit panic attacks in humans and anxiogenic-like effects in some animal models, but CCK receptor antagonists have not been found clinically effective. Yet CCK overactivity appears to be involved in submissive behaviour, and CCKB receptor expression and binding are increased in suicide victims and animal models of anxiety. Preliminary data suggest that involvement of CCK and its receptor subtypes in anxiety can be better described when focusing on distinct endophenotypes, and considering environmental contingencies and confounds originating from interactions with dopamin-, opioid- and glutamatergic neurotransmission. In contrast, NPY is an anti-anxiety peptide with robust effects in various animal models when administrated into several brain regions. Studies with non-peptide antagonists selective for receptor subtypes have revealed the role of endogenous NPY in active coping. At least Y1, Y2 and Y5 receptors in various brain regions are involved, with the strongest evidence for contribution of Y1.
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Affiliation(s)
- J Harro
- Department of Psychology and Psychopharmacological Drug Development Group, Centre of Behavioural and Health Sciences, University of Tartu, Tartu, Estonia.
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18
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Millard A, Gentsch C. Competition for sucrose pellets in tetrads of male Wistar, Fischer or Sprague–Dawley rats: Is intra-group ranking reflected in the level of anxiety? Behav Brain Res 2006; 168:243-54. [PMID: 16360888 DOI: 10.1016/j.bbr.2005.11.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Revised: 11/11/2005] [Accepted: 11/14/2005] [Indexed: 10/25/2022]
Abstract
Competition for palatable food or fluids within groups of rats has been previously used to mirror intra-group ranking. The paradigm of competition for sucrose pellets in non-food-deprived male Wistar rats was here extended from triads to tetrads aiming at evaluating whether the number of poor-performing rats, those animals being likely to model aspects of human psychopathologies (anxiety/depression/social withdrawal), could be increased. To evaluate potential superiority over the previously used Wistar strain, establishment and stability of the ranking was also assessed in tetrads of male Fischer and Sprague-Dawley rats. Clear and stable rank orders were seen in around 60-70% of both triads and tetrads of Wistar rats: a high-performing, a medium-performing and one (in triads) or two (in tetrads) poor-performing rats were identifiable, indicating that the number of poor-performing rats had increased in tetrads. Comparable rank orders were also seen in tetrads of Fischer and Sprague-Dawley rats. At the end of an extended period of repeated testing, tetrads of these two strains, as well as some selected Wistar tetrads, were tested in the elevated zero-maze and plasma corticosterone levels were determined. The differentiation in competition-performance among cage mates was not paralleled by a difference in performance in the elevated zero-maze or in plasma corticosterone levels in any of the three strains. These data indicate that the level of anxiety in a non-social paradigm, the elevated zero-maze, does not reflect the competition-performance within the home cage and thus, the dominant/subordinate status in this food-competition paradigm may not reflect/being caused by different levels of anxiety.
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Affiliation(s)
- Annabelle Millard
- Novartis Institutes for BioMedical Research (NIBR), WSJ386-2.46, CH-4002 Basel, Switzerland
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Rezayat M, Roohbakhsh A, Zarrindast MR, Massoudi R, Djahanguiri B. Cholecystokinin and GABA interaction in the dorsal hippocampus of rats in the elevated plus-maze test of anxiety. Physiol Behav 2005; 84:775-82. [PMID: 15885255 DOI: 10.1016/j.physbeh.2005.03.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2004] [Revised: 02/27/2005] [Accepted: 03/08/2005] [Indexed: 10/25/2022]
Abstract
In the present study, we have investigated the effects and interaction of CCK and GABAergic systems in the dorsal hippocampus of rats using the elevated plus-maze test of anxiety. Bilateral injection of different doses of CCK(8s) (0.01, 0.05 and 0.1 microg/rat) into the dorsal hippocampus (intra-CA1) decreased percentage of open arm time (%OAT) and open arm entries (%OAE) that are representative of anxiogenic-like behavior. The bilateral injection of three doses of LY225910, a selective CCK2 receptor antagonist (0.01, 0.1 and 0.5 microg/rat) produced significant anxiolytic behavior. Although muscimol (GABA(A+)) (0.1, 0.5 and 1 microg/rat, intra-CA1) produced dose dependent increase in %OAT and a slight increase in %OAE, bicuculline (GABA(A-)), (1, 2 and 4 microg/rat, intra-CA1) failed to change the anxiety profile. Both muscimol (0.1 microg/rat) and bicuculline (1 microg/rat), when co-administered with LY225910, reversed the effect of latter drug on anxiety but when co-administered with CCK8s (0.05 microg/rat) showed no effect on anxiety profile. In conclusion, it seems that both CCK and GABAergic systems not only play a part in the modulation of anxiety in the dorsal hippocampus of rats but also have demonstrated a complex interaction as well.
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Affiliation(s)
- Mehdi Rezayat
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, P.O. Box 13145-784, Tehran, Iran.
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Mällo T, Berggård C, Eller M, Damberg M, Oreland L, Harro J. Effect of long-term blockade of CRF(1) receptors on exploratory behaviour, monoamines and transcription factor AP-2. Pharmacol Biochem Behav 2004; 77:855-65. [PMID: 15099932 DOI: 10.1016/j.pbb.2004.02.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2003] [Revised: 02/23/2004] [Accepted: 02/26/2004] [Indexed: 11/18/2022]
Abstract
Corticotropin-releasing factor (CRF) holds a central role in reactions to various environmental stimuli. In the present study, the administration of a selective nonpeptide CRF(1) receptor antagonist, CP-154,526, for 6 days, exerted an anxiolytic effect in the elevated zero-maze (EZM) test. CP-154,526 did not affect behaviour in the exploration box when administered acutely, but increased exploration when administered for 5 days, contingently with daily behavioural testing. This effect, although of lesser magnitude, was also present in animals with neurotoxin DSP-4-induced selective denervation of locus coeruleus (LC) projections. When drug administration and behavioural testing were noncontingent in a 2-week administration schedule, CP-154,526 blocked the habituation-induced increase in exploration. This suggests that drug-environment interaction is an important component in the manifestation of the anxiolytic-like effects of CRF(1) receptor blockade. Long-term administration of CP-154,526 had a decreasing effect on noradrenaline (NA) metabolism in the frontal cortex. No manipulation influenced the levels of the transcription factor AP-2 isoforms in the LC area. AP-2 levels correlated positively with 3-methoxy-4-hydroxyphenylglycol (MHPG) in the frontal cortex of vehicle-treated animals. There was a negative correlation between the NA levels in the hippocampus and AP-2 isoforms in the LC area of naive animals. In contrast, in vehicle-treated animals, this correlation was positive. Treatment with CP-154,526, however, made the associations between LC AP-2 levels and hippocampal NA content negative, as was the case in the naive animals. This suggests that CRF(1) receptor blockade counteracts certain mechanisms of habituation, possibly by reducing the LC activity.
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Affiliation(s)
- Tanel Mällo
- Department of Psychology, Centre of Behavioural and Health Sciences, University of Tartu, Tiigi 78, 50410 Tartu, Estonia
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Lodge DJ, Roques BP, Lawrence AJ. Atypical behavioural responses to CCK-B receptor ligands in Fawn-Hooded rats. Life Sci 2003; 74:1-12. [PMID: 14575808 DOI: 10.1016/j.lfs.2003.03.003] [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: 11/20/2022]
Abstract
At present there is an increasing literature demonstrating heterogeneity of the CCK-B receptor. Recent reports by our laboratory have demonstrated that the Fawn-Hooded rat demonstrates atypical neurochemical responses to CCK4, in vitro. Since the ability of CCK-B receptor ligands to modulate affective state is dependent on the putative receptor subtype activated, the aim of the present study was to examine the behavioural effects of the CCK-B receptor agonist, t-boc-CCK4, and the CCK-B receptor antagonist, Ci-988 in Fawn-Hooded and Wistar Kyoto rats. Interestingly, both t-boc-CCK4 and Ci-988 produced an anxiolytic profile in FH rats as determined by an increased time spent on the open arms of an elevated plus maze, while both drugs were devoid of any behavioural effect in WKY rats, lending further support to the theory that the FH rat strain has an atypical relative proportion of these putative subtypes apparently resulting in a predominantly CCK-B2 receptor effect.
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Affiliation(s)
- Daniel J Lodge
- Department of Pharmacology, Monash University, Wellington Road, Box 13E, Clayton, Victoria 3800, Australia
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Abstract
Cholecystokinin (CCK) is a regulatory peptide hormone, predominantly found in the gastrointestinal tract, and a neurotransmitter present throughout the nervous system. In the gastrointestinal system CCK regulates motility, pancreatic enzyme secretion, gastric emptying, and gastric acid secretion. In the nervous system CCK is involved in anxiogenesis, satiety, nociception, and memory and learning processes. Moreover, CCK interacts with other neurotransmitters in some areas of the CNS. The biological effects of CCK are mediated by two specific G protein coupled receptor subtypes, termed CCK(1) and CCK(2). Over the past fifteen years the search of CCK receptor ligands has evolved from the initial CCK structure derived peptides towards peptidomimetic or non-peptide agonists and antagonists with improved pharmacokinetic profile. This research has provided a broad assortment of potent and selective CCK(1) and CCK(2) antagonists of diverse chemical structure. These antagonists have been discovered through optimization programs of lead compounds which were designed based on the structures of the C-terminal tetrapeptide, CCK-4, or the non-peptide natural compound, asperlicin, or derived from random screening programs. This review covers the main pharmacological and therapeutic aspects of these CCK(1) and CCK(2) antagonist. CCK(1) antagonists might have therapeutic potential for the treatment of pancreatic disorders and as prokinetics for the treatment of gastroesophageal reflux disease, bowel disorders, and gastroparesis. On the other hand, CCK(2) antagonists might have application for the treatment of gastric acid secretion and anxiety disorders.
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Affiliation(s)
- Rosario Herranz
- Instituto de Química Medica (CSIC), Juan de la Cierva 3, E-28006 Madrid, Spain.
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Lodge DJ, Lawrence AJ. The effect of isolation rearing on volitional ethanol consumption and central CCK/dopamine systems in Fawn-Hooded rats. Behav Brain Res 2003; 141:113-22. [PMID: 12742247 DOI: 10.1016/s0166-4328(02)00328-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Numerous studies have demonstrated that socially isolating rats (from weaning) produces a sustained anxious phenotype and an enhanced response to psychostimulant drugs such as amphetamine and cocaine. In addition, isolation rearing has been shown to induce significant changes in the mesolimbic dopamine system. These data indicate that isolation rearing not only induces an anxiogenic phenotype but also induces neurochemical changes in reward nuclei of the brain, which is correlated with an enhanced response to psychostimulants. For these reasons, the effect of isolation rearing on volitional ethanol consumption was examined in Fawn-Hooded (FH) rats and correlated with neurochemical changes in central dopamine and cholecystokinin systems. Social isolation from weaning produced an anxiogenic phenotype as measured by a decreased time spent on the open arms of an elevated plus-maze. Interestingly, isolation-rearing induced a greater proportion of FH rats to acquire preference for ethanol while having no effect on the amount of ethanol consumed by alcohol-preferring rats. In addition, isolation rearing induced a number of changes in central CCK/dopamine systems.
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Affiliation(s)
- Daniel J Lodge
- Department of Pharmacology, Monash University, P.O. Box 13E, Clayton, Vic. 3800, Australia.
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Lodge DJ, Lawrence AJ. The neurochemical effects of anxiolytic drugs are dependent on rearing conditions in Fawn-Hooded rats. Prog Neuropsychopharmacol Biol Psychiatry 2003; 27:451-8. [PMID: 12691780 DOI: 10.1016/s0278-5846(03)00032-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
There is a vast literature examining the neurochemical effects of anxiolytics throughout the rat brain; however, although the behavioural actions of anxiolytic drugs are routinely assessed in animal models of anxiety, the majority of neurochemical studies have been performed in rats with relatively 'normal' behavioural phenotypes. Since there is significant evidence that an anxious phenotype is associated with numerous neurochemical alterations, it is feasible that the central effects of anxiolytics may vary depending on the underlying behavioural state (and corresponding neuropathology) of the experimental animal. For this reason, the aim of the present study was to examine the effect of chronic anxiolytic drug administration on the central CCK and dopamine systems in anxious (isolated from weaning) and nonanxious (group-housed) Fawn-Hooded (FH) rats. It is important to note that these studies were performed in rats with continued access to ethanol, which may affect the responses to anxiolytic treatment. Chronic anxiolytic treatment with the selective CCK-B (CCK(2)) receptor antagonist, Ci-988 (0.3 mg/kg/day ip) or diazepam (2 mg/kg/day ip), induced numerous effects throughout the central nervous system (CNS), with Ci-988 inducing significant changes in the density of dopamine D(2) receptors, and diazepam producing marked changes in both dopamine D(2) and CCK-B receptor binding density as well as preproCCK mRNA expression. Interestingly, the neurochemical effects of these anxiolytic drugs varied significantly depending on the rearing conditions of the rats, demonstrating the importance of using adequate animal models when correlating the behavioural and central effects of drugs acting throughout the CNS.
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Affiliation(s)
- Daniel J Lodge
- Department of Pharmacology, Monash University, Box 13E, Clayton, Victoria 3800, Australia.
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Abstract
Cholecystokinin (CCK) is deeply involved in the control of learning and emotional behaviors. The authors characterize the behavioral properties of Otsuka Long Evans Tokushima Fatty (OLETF) rats, which lack the CCK-A receptor because of a genetic abnormality. In the Morris water-maze task, the OLETF rats showed an impaired spatial memory. In the inhibitory avoidance test, they showed facilitating response 24 h after training. Hypoalgesia was observed in a hot-plate test. In the elevated plus-maze and food neophobia test, OLETF rats showed an anxiety-like response. In addition, OLETF rats were hypoactive in the Morris water-maze and the elevated plus-maze. The results suggest that the OLETF rats showed a spatial memory deficit, hypoactivity and anxiety due, at least in part, to the lack of CCK-A receptors.
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Affiliation(s)
- Xue Liang Li
- Department of Integrative Physiology, Graduate School of Medical Sciences, Kyushu University 60, Fukuoka 812-8582, Japan
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Lodge DJ, Lawrence AJ. Comparative analysis of the central CCK system in Fawn Hooded and Wistar Kyoto rats: extended localisation of CCK-A receptors throughout the rat brain using a novel radioligand. REGULATORY PEPTIDES 2001; 99:191-201. [PMID: 11384782 DOI: 10.1016/s0167-0115(01)00256-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The neuropeptide cholecystokinin has been implicated in the actions of a number of central processes including anxiety and reward. For this reason, the aim of the present study was to compare the density of CCK-A and -B receptors and the mRNA encoding preproCCK throughout the brains of an alcohol-preferring (Fawn Hooded) rat strain with that of a non-alcohol-preferring (Wistar Kyoto) strain of rat. Our study revealed significant differences with regard to the central CCK system of the FH compared to the WKY rat, including differences in CCK-A receptor binding throughout the dorsal medulla, and altered CCK-B binding density throughout the cerebral cortex and reticular nucleus of the thalamus. The most striking result, given the altered behavioural phenotype of the FH rat, was the 33% lower density of CCKmRNA measured throughout the ventral tegmental area of the FH rat when compared to the WKY. This study also reports on a protocol to utilise a novel radioligand, [125I]-D-Tyr-Gly-A-71378, for autoradiographic detection of CCK-A receptors throughout the rat brain. As previously reported, CCK-A receptors were located throughout the area postrema, interpeduncular nucleus and nucleus tractus solitarii; however, binding to CCK-A receptors was also visualised throughout the medial pre-optic area, the arcuate nucleus and the circumventricular regions of the ventral hypothalamus, regions known to contain CCK-A receptors but which were previously undetectable using autoradiography in rat brain.
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Affiliation(s)
- D J Lodge
- Department of Pharmacology, Monash University, Box 13E, Victoria 3800, Clayton, Australia.
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Fox MA, Levine ES, Riley AL. The inability of CCK to block (or CCK antagonists to substitute for) the stimulus effects of chlordiazepoxide. Pharmacol Biochem Behav 2001; 69:77-84. [PMID: 11420071 DOI: 10.1016/s0091-3057(01)00505-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To further examine the relationship between cholecystokinin (CCK) and GABA, the present study assessed the ability of the CCK-A antagonist devazepide and the CCK-B antagonist L-365,260 to substitute for the stimulus effects of chlordiazepoxide (CDP), as well as the ability of CCK-8s to block these effects, in female Long-Evans rats within the conditioned taste aversion baseline of drug discrimination learning. Both devazepide and L-365,260 failed to substitute for the discriminative stimulus properties of CDP, and CCK-8s failed to block its stimulus effects. The benzodiazepine diazepam did substitute for, and the benzodiazepine antagonist flumazenil did block, the stimulus effects of CDP. This suggests that the lack of substitution for, or antagonism of, CDP by the CCK antagonists and CCK-8s, respectively, was not due to the inability of the present design to assess such effects. Possible bases for the current findings, e.g., necessity of an anxiogenic baseline, drug and receptor specificity, as well as the dose-response nature of the interaction, were discussed. Given that a relationship between CCK and GABA has been reported in other designs, the present results suggest that such a relationship may be preparation specific.
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Affiliation(s)
- M A Fox
- Psychopharmacology Laboratory, Department of Psychology, American University, Washington, DC 20016, USA.
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Enhanced cortical extracellular levels of cholecystokinin-like material in a model of anticipation of social defeat in the rat. J Neurosci 2001. [PMID: 11150343 DOI: 10.1523/jneurosci.21-01-00262.2001] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The involvement of cholecystokinin (CCK) in the mechanisms of stress and/or anxiety was assessed by in vivo microdialysis in rats subjected to a social stress paradigm. During the initial 30 min period of each conditioning session, a male Sprague Dawley rat (intruder) was placed in a protective cage inside the cage of a male Tryon Maze Dull rat (resident), allowing unrestricted visual, olfactory, and auditory contacts but precluding close physical contact between them. During the following 15 min period, both the protective cage and the resident were removed (nondefeated intruders) or only the protective cage was removed allowing the resident to attack the intruder (defeated rats). This procedure was repeated once daily for 4 d. On the fifth day, a guide cannula was implanted into the prefrontal cortex of intruders. During a single 30 min test session, performed 4 d later, intruders were subjected to only the 30 min protected confrontation to the resident. Anxiety-like behavior (immobility, ultrasonic vocalizations, and defensive postures), associated with an increase (approximately +100% above baseline) in cortical outflow of CCK-like material (CCKLM), were observed in defeated intruders. Pretreatment with diazepam (5 mg/kg, i.p.), but not buspirone (0.5-2 mg/kg, i.p.), prevented both the anxiety-related behavior and CCKLM overflow. The selective CCK-B receptor antagonist CI-988 (2 mg/kg, i.p.) reduced the anxiety-like behavior without affecting the increase in CCKLM outflow. These data indicate that anticipation of social defeat induces a marked activation of cortical CCKergic neurons associated with anxiety-related behaviors in rats.
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Cook MN, Williams RW, Flaherty L. Anxiety-related behaviors in the elevated zero-maze are affected by genetic factors and retinal degeneration. Behav Neurosci 2001. [DOI: 10.1037/0735-7044.115.2.468] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Yamamoto Y, Akiyoshi J, Kiyota A, Katsuragi S, Tsutsumi T, Isogawa K, Nagayama H. Increased anxiety behavior in OLETF rats without cholecystokinin-A receptor. Brain Res Bull 2000; 53:789-92. [PMID: 11179844 DOI: 10.1016/s0361-9230(00)00407-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cholecystokinin (CCK) may have a role in the mediation of human panic disorder and anxiogenic (anxiolytic)-like activity in an animal model of anxiety. Otsuka Long Evans Tokushima Fatty (OLETF) rats lacked CCK A receptors (CCKAR) because of a genetic abnormality. In order to elucidate the involvement of CCKAR in the regulation of anxiety, we investigated the exploratory behavior on elevated plus-maze test, the black and white box test, and open field test with OLETF rats in comparison with normal [Long-Evans Tokushima Otsuka (LETO)] rats. And OLETF rats increased the number of stretched attend postures and decreased open arm entry and the % time of open arm in an elevated plus-maze test. Time spent in the white box decreased significantly in OLETF rats than LETO rats. The total line crossing decreased significantly in OLETF rats compared to LETO rats. The missing CCKAR had a significant anxiogenic-like effect. These data support the involvement of the CCKAR in the neurobiological mechanism of anxiety.
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Affiliation(s)
- Y Yamamoto
- Department of Neuropsychiatry, Oita Medical University, Hasama-Machi, Oita, Japan
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Pähkla R, Kask A, Rägo L. Differential effects of beta-carbolines and antidepressants on rat exploratory activity in the elevated zero-maze. Pharmacol Biochem Behav 2000; 65:737-42. [PMID: 10764931 DOI: 10.1016/s0091-3057(99)00265-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Present experiments were designed to compare the effects of antidepressants desipramine (10 and 20 mg/kg IP) and fluoxetine (5 and 10 mg/kg IP) with anxiogenic beta-carboline DMCM (0.5 and 1.0 mg/kg IP) in the elevated zero-maze test in rats. The second aim of this study was to assess the effects of pinoline (6-methoxy-1,2,3, 4-tetrahydro-beta-carboline) in the rat elevated zero-maze test in comparison with structurally unrelated beta-carboline DMCM and antidepressants. The time spent in the open part of the elevated zero-maze was not significantly affected by antidepressants, but was decreased by beta-carbolines pinoline and DMCM. The number of line crossings in the open parts and the number of head dips were also decreased more by beta-carbolines in comparison with antidepressants. Latency to enter the open part was statistically significantly increased only by DMCM. Measurement of locomotor activity in a separate experiment indicated that activity of the rats' time moving, distance traveled, and number of rearings were reduced by all four drugs studied. These results demonstrate that the effects of antidepressants in the elevated zero-maze test differ from the effects of the reference anxiogenic compound DMCM. The effects of pinoline and DMCM in the zero-maze test were similar, which suggests the involvement of mechanisms other than serotoninergic in the action of pinoline.
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Affiliation(s)
- R Pähkla
- Department of Pharmacology, University of Tartu, Ravila 19, 50411, Tartu, Estonia
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Abstract
This review provides an overview of preclinical and clinical evidence of a role for the neuroactive peptides cholecystokinin (CCK), corticotropin-releasing factor (CRF), neuropeptide Y (NPY), tachykinins (i.e., substance P, neurokinin [NK] A and B), and natriuretic peptides in anxiety and/or stress-related disorders. Results obtained with CCK receptor antagonists in animal studies have been highly variable, and clinical trials with several of these compounds in anxiety disorders have been unsuccessful so far. However, future investigations using CCK receptor antagonists with better pharmacokinetic characteristics and animal models other than those validated with the classical anxiolytics benzodiazepines may permit a more precise evaluation of the potential of these compounds as anti-anxiety agents. Results obtained with peptide CRF receptor antagonists in animal models of anxiety convincingly demonstrated that the blockade of central CRF receptors may yield anxiolytic-like activity. However, the discovery of nonpeptide and more lipophilic CRF receptor antagonists is essential for the development of these agents as anxiolytics. Similarly, there is clear preclinical evidence that the central infusion of NPY and NPY fragments selective for the Y1 receptor display anxiolytic-like effects in a variety of tests. However, synthetic nonpeptide NPY receptor agonists are still lacking, thereby hampering the development of NPY anxiolytics. Unlike selective NK1 receptor antagonists, which have variable effects in anxiety models, peripheral administration of selective NK2 receptor antagonists and central infusion of natriuretic peptides produce clear anxiolytic-like activity. Taken as a whole, these findings suggest that compounds targeting specific neuropeptide receptors may become an alternative to benzodiazepines for the treatment of anxiety disorders.
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Affiliation(s)
- G Griebel
- CNS Research Department, Synthélabo Recherche, Bagneux, France
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