1
|
King H, Reiber M, Philippi V, Stirling H, Aulehner K, Bankstahl M, Bleich A, Buchecker V, Glasenapp A, Jirkof P, Miljanovic N, Schönhoff K, von Schumann L, Leenaars C, Potschka H. Anesthesia and analgesia for experimental craniotomy in mice and rats: a systematic scoping review comparing the years 2009 and 2019. Front Neurosci 2023; 17:1143109. [PMID: 37207181 PMCID: PMC10188949 DOI: 10.3389/fnins.2023.1143109] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/27/2023] [Indexed: 05/21/2023] Open
Abstract
Experimental craniotomies are a common surgical procedure in neuroscience. Because inadequate analgesia appears to be a problem in animal-based research, we conducted this review and collected information on management of craniotomy-associated pain in laboratory mice and rats. A comprehensive search and screening resulted in the identification of 2235 studies, published in 2009 and 2019, describing craniotomy in mice and/or rats. While key features were extracted from all studies, detailed information was extracted from a random subset of 100 studies/year. Reporting of perioperative analgesia increased from 2009 to 2019. However, the majority of studies from both years did not report pharmacologic pain management. Moreover, reporting of multimodal treatments remained at a low level, and monotherapeutic approaches were more common. Among drug groups, reporting of pre- and postoperative administration of non-steroidal anti-inflammatory drugs, opioids, and local anesthetics in 2019 exceeded that of 2009. In summary, these results suggest that inadequate analgesia and oligoanalgesia are persistent issues associated with experimental intracranial surgery. This underscores the need for intensified training of those working with laboratory rodents subjected to craniotomies. Systematic review registration https://osf.io/7d4qe.
Collapse
Affiliation(s)
- Hannah King
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Maria Reiber
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Vanessa Philippi
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Helen Stirling
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Katharina Aulehner
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Marion Bankstahl
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - André Bleich
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - Verena Buchecker
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Aylina Glasenapp
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - Paulin Jirkof
- Office for Animal Welfare and 3Rs, University of Zurich, Zurich, Switzerland
| | - Nina Miljanovic
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Katharina Schönhoff
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Lara von Schumann
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
| | - Cathalijn Leenaars
- Hannover Medical School, Institute for Laboratory Animal Science, Hanover, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig Maximilian University of Munich, Munich, Germany
- *Correspondence: Heidrun Potschka,
| |
Collapse
|
2
|
Simone JJ, Baumbach JL, McPherson J, McCormick CM. Adolescent CB1 receptor antagonism influences subsequent social interactions and neural activity in female rats. Int J Dev Neurosci 2020; 80:319-333. [PMID: 32220094 DOI: 10.1002/jdn.10028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 03/18/2020] [Accepted: 03/19/2020] [Indexed: 01/05/2023] Open
Abstract
We previously demonstrated that repeated exposure to the CB1 receptor antagonist/inverse agonist AM251 in adolescence (PND 30-44) increased social interactions in female rats when tested 48 h after the final exposure to the antagonist. Here, we investigated whether the increased sociality would be present after a longer drug washout period (5 days) in both male and female rats (experiment 1), and sought to identify candidate brain regions that may explain the observed differences in social behaviours between AM251 and vehicle-treated female rats (experiment 2). While drug-free, adolescent AM251 treatment increased social interactions in females and not in males. AM251 female rats had increased neural activity (as measured by the expression of early growth response protein-1; EGR-1) in the nucleus accumbens shell and cingulate gyrus of the medial prefrontal cortex, with no observed differences in EGR-1 expression in the dorsal hippocampus, nucleus accumbens core, or prelimbic and infralimbic subdivisions of the medial prefrontal cortex relative to vehicle rats. Together, these results demonstrate a sex-specific role of adolescent endocannabinoid signalling in the normative development of social behaviours and provide further support for adolescence as a vulnerable period for the effects of altered endocannabinoid signalling.
Collapse
Affiliation(s)
- Jonathan J Simone
- Department of Biological Sciences, Brock University, St. Catharines, ON, Canada
| | - Jennet L Baumbach
- Department of Psychology, Brock University, St. Catharines, ON, Canada
| | | | - Cheryl M McCormick
- Department of Biological Sciences, Brock University, St. Catharines, ON, Canada.,Department of Psychology, Brock University, St. Catharines, ON, Canada.,Centre for Neuroscience, Brock University, St. Catharines, ON, Canada
| |
Collapse
|
3
|
Bodnar RJ. Endogenous opioid modulation of food intake and body weight: Implications for opioid influences upon motivation and addiction. Peptides 2019; 116:42-62. [PMID: 31047940 DOI: 10.1016/j.peptides.2019.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 03/04/2019] [Accepted: 04/08/2019] [Indexed: 12/12/2022]
Abstract
This review is part of a special issue dedicated to Opioid addiction, and examines the influential role of opioid peptides, opioid receptors and opiate drugs in mediating food intake and body weight control in rodents. This review postulates that opioid mediation of food intake was an example of "positive addictive" properties that provide motivational drives to maintain opioid-seeking behavior and that are not subject to the "negative addictive" properties associated with tolerance, dependence and withdrawal. Data demonstrate that opiate and opioid peptide agonists stimulate food intake through homeostatic activation of sensory, metabolic and energy-related In contrast, general, and particularly mu-selective, opioid receptor antagonists typically block these homeostatically-driven ingestive behaviors. Intake of palatable and hedonic food stimuli is inhibited by general, and particularly mu-selective, opioid receptor antagonists. The selectivity of specific opioid agonists to elicit food intake was confirmed through the use of opioid receptor antagonists and molecular knockdown (antisense) techniques incapacitating specific exons of opioid receptor genes. Further extensive evidence demonstrated that homeostatic and hedonic ingestive situations correspondingly altered the levels and expression of opioid peptides and opioid receptors. Opioid mediation of food intake was controlled by a distributed brain network intimately related to both the appetitive-consummatory sites implicated in food intake as well as sites intimately involved in reward and reinforcement. This emergent system appears to sustain the "positive addictive" properties providing motivational drives to maintain opioid-seeking behavior.
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology, Queens College, City University of New York, United States; Psychology Doctoral Program and CUNY Neuroscience Collaborative, The Graduate Center of the City University of New York, United States.
| |
Collapse
|
4
|
Cruz-Martínez AM, Tejas-Juárez JG, Mancilla-Díaz JM, Florán-Garduño B, López-Alonso VE, Escartín-Pérez RE. CB1 receptors in the paraventricular nucleus of the hypothalamus modulate the release of 5-HT and GABA to stimulate food intake in rats. Eur Neuropsychopharmacol 2018; 28:1247-1259. [PMID: 30217553 DOI: 10.1016/j.euroneuro.2018.08.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/13/2018] [Accepted: 08/07/2018] [Indexed: 12/12/2022]
Abstract
Endocannabinoids and their receptors not only contribute to the control of natural processes of appetite regulation and energy balance but also have an important role in the pathogenesis of obesity. CB1 receptors (CB1R) are expressed in several hypothalamic nuclei, including the paraventricular nucleus (PVN), where induce potent orexigenic responses. Activation of CB1R in the PVN induces hyperphagia by modulating directly or indirectly orexigenic and anorexigenic signals; however, interaction among these mediators has not been clearly defined. CB1R mRNA is expressed in serotonergic neurons that innervate the PVN, and activation of 5-HT receptors in the PVN constitutes an important satiety signal. Some GABAergic terminals are negatively influenced by 5-HT, suggesting that the hyperphagic effect of CB1R activation could involve changes in serotonergic and GABAergic signaling in the PVN. Accordingly, the present study was aimed to characterize the neurochemical mechanisms related to the hyperphagic effects induced by activation of CB1R in the PVN, studying in vitro and in vivo changes induced by direct activation these receptors. Here, we have found that the neurochemical mechanisms activated by stimulation of CB1 receptors in the PVN involve inhibition of 5-HT release, resulting in a decrease of serotonergic activity mediated by 5-HT1A and 5-HT1B receptors and inducing disinhibition of GABA release to stimulate food intake. In conclusion, these neurochemical changes in the PVN are determinant to the cannabinoid-induced stimulation of food intake. Our findings provide evidence of a functional connection among CB1R and serotonergic and GABAergic systems on the control of appetite regulation mediated by endocannabinoids.
Collapse
Affiliation(s)
- Ana María Cruz-Martínez
- Department of Pharmacology, CINVESTAV-IPN, 2508 Av. Instituto Politécnico Nacional, San Pedro Zacatenco, Ciudad de México 07360, México
| | - Juan Gabriel Tejas-Juárez
- Multidisciplinary Academic Division of Comalcalco, Universidad Juárez Autónoma de Tabasco, Ranchería Sur 4(ª) Sección, Tabasco 86650, México
| | - Juan Manuel Mancilla-Díaz
- Laboratory of Neurobiology of Eating, Universidad Nacional Autónoma de México, FES Iztacala, 1 Av. de los Barrios, Los Reyes Iztacala, Tlalnepantla 54090, México
| | - Benjamín Florán-Garduño
- Department of Physiology, Biophysics and Neuroscience, CINVESTAV-IPN, 2508 Av. Instituto Politécnico Nacional, San Pedro Zacatenco, Ciudad de México 07360, México
| | - Verónica Elsa López-Alonso
- Laboratory of Neurobiology of Eating, Universidad Nacional Autónoma de México, FES Iztacala, 1 Av. de los Barrios, Los Reyes Iztacala, Tlalnepantla 54090, México
| | - Rodrigo Erick Escartín-Pérez
- Laboratory of Neurobiology of Eating, Universidad Nacional Autónoma de México, FES Iztacala, 1 Av. de los Barrios, Los Reyes Iztacala, Tlalnepantla 54090, México.
| |
Collapse
|
5
|
Abstract
The opioid receptor system plays a major role in the regulation of mood, reward, and pain. The opioid receptors therefore make attractive targets for the treatment of many different conditions, including pain, depression, and addiction. However, stimulation or blockade of any one opioid receptor type often leads to on-target adverse effects that limit the clinical utility of a selective opioid agonist or antagonist. Literature precedent suggests that the opioid receptors do not act in isolation and that interactions among the opioid receptors and between the opioid receptors and other proteins may produce clinically useful targets. Multifunctional ligands have the potential to elicit desired outcomes with reduced adverse effects by allowing for the activation of specific receptor conformations and/or signaling pathways promoted as a result of receptor oligomerization or crosstalk. In this chapter, we describe several classes of multifunctional ligands that interact with at least one opioid receptor. These ligands have been designed for biochemical exploration and the treatment of a wide variety of conditions, including multiple kinds of pain, depression, anxiety, addiction, and gastrointestinal disorders. The structures, pharmacological utility, and therapeutic drawbacks of these classes of ligands are discussed.
Collapse
Affiliation(s)
- Jessica P Anand
- Department of Pharmacology, Medical School and the Edward F. Domino Research Center, University of Michigan, Ann Arbor, MI, USA.
| | - Deanna Montgomery
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
6
|
Simone JJ, Baumbach JL, McCormick CM. Effects of CB1 receptor antagonism and stress exposures in adolescence on socioemotional behaviours, neuroendocrine stress responses, and expression of relevant proteins in the hippocampus and prefrontal cortex in rats. Neuropharmacology 2017; 128:433-447. [PMID: 29092785 DOI: 10.1016/j.neuropharm.2017.10.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 10/12/2017] [Accepted: 10/23/2017] [Indexed: 01/07/2023]
Abstract
Little is known about the consequences of altered endocannabinoid signalling in adolescence. We hypothesized that CB1 receptor antagonism (AM251, 1 mg/kg) and stress exposures (1 h confinement stress) in adolescence (daily, postnatal days 30-44) would interact to increase neuroendocrine stress responses and anxiety when investigated a minimum of 24 h after drug and stress treatments; these treatment effects were independent of each other. Changes in homecage behaviour and in weight gain confirmed that both males and females were sensitive to the treatments. Nevertheless, in males, repeated AM251 administration was without effect on any of the measures investigated in days post-treatment. Males had reduced corticosterone release to the repeated stress and had increased GAD67 expression in the ventral hippocampus under baseline conditions. In females, AM251 also reduced weight gain and increased stereotypic behaviours in the homecage; these same females showed increased sociality, reduced CB1 receptor expression in the dorsal hippocampus, and increased GAD67 expression in the prefrontal cortex. Further, females exposed to repeated stress had enhanced recovery to baseline corticosterone concentrations after stress. The inclusion of a non-injected comparison group also revealed stress of injection effects in both sexes that otherwise would have been masked. Together, the findings demonstrate effects of CB1 receptor antagonism and stress that were more evident in females than males, suggesting that females may be more vulnerable to the consequences of disrupted endocannabinoid signalling during adolescence.
Collapse
Affiliation(s)
- Jonathan J Simone
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
| | - Jennet L Baumbach
- Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada
| | - Cheryl M McCormick
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada; Department of Psychology, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada; Centre for Neuroscience, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, Ontario L2S 3A1, Canada.
| |
Collapse
|
7
|
Rodgers R. Bench to bedside in appetite research: Lost in translation? Neurosci Biobehav Rev 2017; 76:163-173. [DOI: 10.1016/j.neubiorev.2016.08.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 08/22/2016] [Accepted: 08/24/2016] [Indexed: 12/19/2022]
|
8
|
Bodnar RJ. Endogenous opioids and feeding behavior: A decade of further progress (2004-2014). A Festschrift to Dr. Abba Kastin. Peptides 2015; 72:20-33. [PMID: 25843025 DOI: 10.1016/j.peptides.2015.03.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 03/23/2015] [Accepted: 03/25/2015] [Indexed: 12/13/2022]
Abstract
Functional elucidation of the endogenous opioid system temporally paralleled the creation and growth of the journal, Peptides, under the leadership of its founding editor, Dr. Abba Kastin. He was prescient in publishing annual and uninterrupted reviews on Endogenous Opiates and Behavior that served as a microcosm for the journal under his stewardship. This author published a 2004 review, "Endogenous opioids and feeding behavior: a thirty-year historical perspective", summarizing research in this field between 1974 and 2003. The present review "closes the circle" by reviewing the last 10 years (2004-2014) of research examining the role of endogenous opioids and feeding behavior. The review summarizes effects upon ingestive behavior following administration of opioid receptor agonists, in opioid receptor knockout animals, following administration of general opioid receptor antagonists, following administration of selective mu, delta, kappa and ORL-1 receptor antagonists, and evaluating opioid peptide and opioid receptor changes in different food intake models.
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Behavioral and Cognitive Neuroscience Doctoral Program Cluster, Queens College, City University of New York, Flushing, NY 11367, United States.
| |
Collapse
|
9
|
Méndez-Díaz M, Amancio-Belmont O, Hernández-Vázquez E, Ruiz-Contreras AE, Hernández-Luis F, Prospéro-García O. ENP11, a potential CB1R antagonist, induces anorexia in rats. Pharmacol Biochem Behav 2015; 135:177-81. [DOI: 10.1016/j.pbb.2015.06.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 05/12/2015] [Accepted: 06/10/2015] [Indexed: 11/29/2022]
|
10
|
Effects of co-administration of 2-arachidonylglycerol (2-AG) and a selective µ-opioid receptor agonist into the nucleus accumbens on high-fat feeding behaviors in the rat. Brain Res 2015; 1618:309-15. [PMID: 26100333 DOI: 10.1016/j.brainres.2015.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 05/26/2015] [Accepted: 06/12/2015] [Indexed: 12/14/2022]
Abstract
Previous research has demonstrated that the nucleus accumbens is a site where opioids and cannabinoids interact to alter feeding behavior. However, the influence of the endocannabinoid 2-arachidonylglycerol (2-AG) on the well-characterized model of intra-accumbens opioid driven high-fat feeding behavior has not been explored. The present experiments examined high-fat feeding associated behaviors produced by the interaction of 2-AG and the μ-opioid receptor agonist DAla(2),N,Me-Phe(4),Gly-ol(5)-enkaphalin (DAMGO) administered into the nucleus accumbens. Sprague-Dawley rats were implanted with bilateral cannulae aimed at the nucleus accumbens and were co-administered both a sub-threshold dose of 2-AG (0 or 0.25 μg/0.5 μl/side) and DAMGO (0, 0.025 μg or 0.25 μg/0.5 μl/side) in all dose combinations, and in a counterbalanced order. Animals were then immediately allowed a 2h-unrestricted access period to a palatable high-fat diet. Consumption, number and duration of food hopper entries, and locomotor activity were all monitored. DAMGO treatment led to an increase in multiple behaviors, including consumption, duration of food hopper entry, and locomotor activity. However, combined intra-accumbens administration of DAMGO and a subthreshold dose of 2-AG led to a significant increase in number of food hopper entries and locomotor activity, compared to DAMGO by itself. The results confirm that intra-accumbens administration of subthreshold dose of the endogenous cannabinoid 2-AG increases the DAMGO-induced approach and locomotor behaviors associated with high-fat feeding.
Collapse
|
11
|
Nimczick M, Decker M. New Approaches in the Design and Development of Cannabinoid Receptor Ligands: Multifunctional and Bivalent Compounds. ChemMedChem 2015; 10:773-86. [DOI: 10.1002/cmdc.201500041] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Indexed: 12/22/2022]
|
12
|
D’Addario C, Micioni Di Bonaventura M, Pucci M, Romano A, Gaetani S, Ciccocioppo R, Cifani C, Maccarrone M. Endocannabinoid signaling and food addiction. Neurosci Biobehav Rev 2014; 47:203-24. [DOI: 10.1016/j.neubiorev.2014.08.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Revised: 07/28/2014] [Accepted: 08/18/2014] [Indexed: 10/24/2022]
|
13
|
Wright FL, Rodgers RJ. Behavioural profile of exendin-4/naltrexone dose combinations in male rats during tests of palatable food consumption. Psychopharmacology (Berl) 2014; 231:3729-44. [PMID: 24682505 DOI: 10.1007/s00213-014-3507-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 02/12/2014] [Indexed: 12/25/2022]
Abstract
RATIONALE The glucagon-like peptide 1 receptor (GLP-1R) agonist exendin-4 potently suppresses food intake in animals and humans. However, little is known about the behavioural specificity of this effect either when administered alone or when co-administered with another anorectic agent. OBJECTIVES The present study characterises the effects of exendin-4, both alone and in combination with naltrexone, on behaviours displayed by male rats during tests with palatable mash. METHODS Experiment 1 examined the dose-response effects of exendin-4 (0.025-2.5 μg/kg, IP), while experiment 2 profiled the effects of low-dose combinations of the peptide (0.025 and 0.25 μg/kg) and naltrexone (0.1 mg/kg). RESULTS In experiment 1, exendin-4 dose dependently suppressed food intake as well as the frequency and rate of eating. However, these effects were accompanied by dose-dependent reductions in all active behaviours and, at 2.5 μg/kg, a large increase in resting and disruption of the behavioural satiety sequence (BSS). In experiment 2, while exendin-4 (0.25 μg/kg) and naltrexone each produced a significant reduction in intake and feeding behaviour (plus an acceleration in the BSS), co-treatment failed to produce stronger effects than those seen in response to either compound alone. CONCLUSION Similarities between the behavioural signature of exendin-4 and that previously reported for the emetic agent lithium chloride would suggest that exendin-4 anorexia is related to the aversive effects of the peptide. Furthermore, as low-dose combinations of the peptide with naltrexone failed to produce an additive/synergistic anorectic effect, this particular co-treatment strategy would not appear to have therapeutic significance.
Collapse
Affiliation(s)
- F L Wright
- Behavioural Neuroscience Laboratory, Institute of Psychological Sciences, University of Leeds, Leeds, LS2 9JT, UK, England
| | | |
Collapse
|
14
|
Cristino L, Becker T, Di Marzo V. Endocannabinoids and energy homeostasis: an update. Biofactors 2014; 40:389-97. [PMID: 24752980 DOI: 10.1002/biof.1168] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 04/06/2014] [Indexed: 01/08/2023]
Abstract
The endocannabinoid system (ECS) is a widespread intercellular signaling system that plays a critical role in energy homeostasis, meant as the precise matching of caloric intake with energy expenditure which normally keeps body weight stable over time. Complex interactions between environmental and neurohormonal systems directly contribute to the balance of energy homeostasis. This review highlights established and more recent data on the brain circuits in which the ECS plays an important regulatory role, with focus on the hypothalamus, a region where numerous interacting systems regulating feeding, satiety, stress, and other motivational states coexist. Although not meant as an exhaustive review of the field, this article will discuss how endocannabinoid tone, in addition to reinforcing reward circuitries and modulating food intake and the salience of food, controls lipid and glucose metabolism in several peripheral organs, particularly the liver and adipose tissue. Direct actions in the skeletal muscle and pancreas are also emerging and are briefly discussed. This review provides new perspectives into endocannabinoid control of the neurochemical causes and consequences of energy homeostasis imbalance, a knowledge that might lead to new potential treatments for obesity and related morbidities.
Collapse
Affiliation(s)
- Luigia Cristino
- Endocannabinoid Research Group, Institute of Biomolecular Chemistry, CNR, Pozzuoli, Italy
| | | | | |
Collapse
|
15
|
Fernández-Fernández C, Callado LF, Girón R, Sánchez E, Erdozain AM, López-Moreno JA, Morales P, Rodríguez de Fonseca F, Fernández-Ruiz J, Goya P, Meana JJ, Martín MI, Jagerovic N. Combining rimonabant and fentanyl in a single entity: preparation and pharmacological results. DRUG DESIGN DEVELOPMENT AND THERAPY 2014; 8:263-77. [PMID: 24591816 PMCID: PMC3934591 DOI: 10.2147/dddt.s55045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Based on numerous pharmacological studies that have revealed an interaction between cannabinoid and opioid systems at the molecular, neurochemical, and behavioral levels, a new series of hybrid molecules has been prepared by coupling the molecular features of two wellknown drugs, ie, rimonabant and fentanyl. The new compounds have been tested for their affinity and functionality regarding CB1 and CB2 cannabinoid and μ opioid receptors. In [35S]-GTPγS (guanosine 5′-O-[gamma-thio]triphosphate) binding assays from the post-mortem human frontal cortex, they proved to be CB1 cannabinoid antagonists and μ opioid antagonists. Interestingly, in vivo, the new compounds exhibited a significant dual antagonist action on the endocannabinoid and opioid systems.
Collapse
Affiliation(s)
| | - Luis F Callado
- Departamento de Farmacología, Universidad del Pais Vasco, UPV/EHU, CIBERSAM, Leioa, Spain
| | - Rocío Girón
- Departamento de Farmacología y Nutrición, Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - Eva Sánchez
- Departamento de Farmacología y Nutrición, Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - Amaia M Erdozain
- Departamento de Farmacología, Universidad del Pais Vasco, UPV/EHU, CIBERSAM, Leioa, Spain
| | | | | | | | - Javier Fernández-Ruiz
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, CIBERNED, IRYCIS, Universidad Complutense de Madrid, Madrid, Spain
| | - Pilar Goya
- Instituto de Química Médica, CSIC, Madrid, Spain
| | - J Javier Meana
- Departamento de Farmacología, Universidad del Pais Vasco, UPV/EHU, CIBERSAM, Leioa, Spain
| | - M Isabel Martín
- Departamento de Farmacología y Nutrición, Ciencias de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | | |
Collapse
|
16
|
Wright FL, Rodgers RJ. On the behavioural specificity of hypophagia induced in male rats by mCPP, naltrexone, and their combination. Psychopharmacology (Berl) 2014; 231:787-800. [PMID: 24114428 DOI: 10.1007/s00213-013-3295-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 09/16/2013] [Indexed: 12/11/2022]
Abstract
RATIONALE Serotonergic (5-hydroxytryptamine, 5-HT) and opioidergic mechanisms are intimately involved in appetite regulation. OBJECTIVES In view of recent evidence of positive anorectic interactions between opioid and various non-opioid substrates, our aim was to assess the behavioural specificity of anorectic responses to the opioid receptor antagonist naltrexone, the 5-HT2C/1B receptor agonist mCPP and their combination. METHODS Behavioural profiling techniques, including the behavioural satiety sequence (BSS), were used to examine acute drug effects in non-deprived male rats tested with palatable mash. Experiment 1 characterised the dose-response profile of mCPP (0.1-3.0 mg/kg), while experiment 2 assessed the effects of combined treatment with a sub-anorectic dose of mCPP (0.1 mg/kg) and one of two low doses of naltrexone (0.1 and 1.0 mg/kg). RESULTS Experiment 1 confirmed the dose-dependent anorectic efficacy of mCPP, with robust effects on intake and feeding-related measures observed at 3.0 mg/kg. However, that dose was also associated with other behavioural alterations including increased grooming, reductions in locomotion and sniffing, and disruption of the BSS. In experiment 2, naltrexone dose-dependently reduced food intake and time spent feeding, effects accompanied by a behaviourally selective acceleration in the BSS. However, the addition of 0.1 mg/kg mCPP did not significantly alter the behavioural changes observed in response to either dose of naltrexone given alone. CONCLUSIONS In contrast to recently reported positive anorectic interactions involving low-dose combinations of opioid receptor antagonists or mCPP with cannabinoid CB1 receptor antagonists, present results would not appear to provide any support for potentially clinically relevant anorectic interactions between opioid and 5-HT2C/1B receptor mechanisms.
Collapse
Affiliation(s)
- F L Wright
- Behavioural Neuroscience Laboratory, Institute of Psychological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | | |
Collapse
|
17
|
Acute behavioural effects of bupropion and naltrexone, alone and in combination, in non-deprived male rats presented with palatable mash. Psychopharmacology (Berl) 2013; 228:291-307. [PMID: 23455599 DOI: 10.1007/s00213-013-3036-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 02/11/2013] [Indexed: 01/28/2023]
Abstract
RATIONALE In appetite research, drugs frequently progress to clinical trials on the basis of outcome (reduced food intake/body weight gain) with insufficient attention to process (behavioural analysis). Although bupropion and naltrexone (alone and in combination) reduce food consumption in rodents and humans, their effects on behaviour during feeding tests have not been thoroughly investigated. OBJECTIVES This study aimed to assess the behavioural specificity of anorectic responses to bupropion, naltrexone and their combination. METHODS Video analysis was employed to characterise the behavioural effects of acute systemic treatment with bupropion (10.0-40.0 mg/kg), naltrexone (0.1-3.0 mg/kg) and combined bupropion (20 mg/kg) plus naltrexone (0.1-1.0 mg/kg) in non-deprived male rats exposed for 1 h to palatable mash. Particular attention was paid to the behavioural satiety sequence (BSS). RESULTS In experiment 1, the anorectic response to 40 mg/kg bupropion was associated with significant psychomotor stimulation and a complete disruption of the BSS. In experiment 2, the anorectic response to 3 mg/kg naltrexone was associated with an accelerated but otherwise normal BSS. In experiment 3, the co-administration of 20 mg/kg bupropion and naltrexone (0.1 and 1.0 mg/kg) not only produced an additive anorectic profile (including a reduced rate of eating), but the addition of the opioid receptor antagonist also concurrently attenuated the psychomotor stimulant response to the atypical antidepressant. CONCLUSIONS Low-dose co-treatment with naltrexone and bupropion produces a stronger suppression of appetite than that seen with either agent alone and has the additional advantage of reducing some of the unwanted effects of bupropion.
Collapse
|
18
|
Abstract
Endocannabinoids and cannabinoid CB1 receptors are known to play a generalized role in energy homeostasis. However, clinical trials with the first generation of CB1 blockers, now discontinued due to psychiatric side effects, were originally designed to reduce food intake and body weight rather than the metabolic risk factors associated with obesity. In this review, we discuss how, in addition to promoting energy intake, endocannabinoids control lipid and glucose metabolism in several peripheral organs, particularly the liver and adipose tissue. Direct actions in skeletal muscle and pancreas are also emerging. This knowledge may help in the design of future therapies for the metabolic syndrome.
Collapse
|
19
|
Wright FL, Rodgers RJ. Low dose naloxone attenuates the pruritic but not anorectic response to rimonabant in male rats. Psychopharmacology (Berl) 2013; 226:415-31. [PMID: 23142959 DOI: 10.1007/s00213-012-2916-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 10/25/2012] [Indexed: 10/27/2022]
Abstract
RATIONALE Previous research suggests that the acute anorectic effect of cannabinoid CB1 receptor antagonist/inverse agonists may be secondary to response competition from the compulsive scratching and grooming syndrome characteristic of these agents. OBJECTIVES As the pruritic effect of rimonabant can be attenuated by the opioid receptor antagonist naloxone, these studies test the prediction that naloxone co-treatment should prevent acute rimonabant anorexia. METHODS Two experiments comprehensively profiled the behavioural effects of an anorectic dose of rimonabant (1.5 mg/kg) in the absence or presence of naloxone (experiment 1: 0.01 or 0.1 mg/kg; experiment 2: 0.05 mg/kg). RESULTS In both experiments, rimonabant not only significantly suppressed food intake and time spent eating but also induced compulsive scratching and grooming. In experiment 1, although the lower dose of naloxone seemed to weakly attenuate the effects of rimonabant both on ingestive and compulsive behaviours, the higher dose more strongly suppressed the compulsive elements but did not significantly affect the anorectic response. The results of experiment 2 showed that naloxone at a dose which markedly attenuated rimonabant-induced grooming and scratching did not alter the effects of the compound on food intake or time spent feeding. The apparent independence of the ingestive and compulsive effects of rimonabant was confirmed by the observation that despite a 'normalising' effect of naloxone co-treatment on behavioural structure (BSS), the opioid antagonist did not impact the suppressant effect of rimonabant on peak feeding. CONCLUSION The acute anorectic response to rimonabant would not appear to be secondary to compulsive scratching and grooming.
Collapse
Affiliation(s)
- F L Wright
- Behavioural Neuroscience Laboratory, Institute of Psychological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | | |
Collapse
|
20
|
Méndez-Díaz M, Rueda-Orozco PE, Ruiz-Contreras AE, Prospéro-García O. The endocannabinoid system modulates the valence of the emotion associated to food ingestion. Addict Biol 2012; 17:725-35. [PMID: 21182571 PMCID: PMC3116974 DOI: 10.1111/j.1369-1600.2010.00271.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Endocannabinoids (eCBs) are mediators of the homeostatic and hedonic systems that modulate food ingestion. Hence, eCBs, by regulating the hedonic system, may be modulating the valence of the emotion associated to food ingestion (positive: pleasant or negative: unpleasant). Our first goal was to demonstrate that palatable food induces conditioned place preference (CPP), hence a positive-valence emotion. Additionally, we analyzed if this CPP is blocked by AM251, inducing a negative valence emotion, meaning avoiding the otherwise pursued compartment. The second goal was to demonstrate that CPP induced by regular food would be strengthened by the simultaneous administration of anandamide or oleamide, and if such, CPP is blocked by AM251. Finally, we tested the capacity of eCBs (without food) to induce CPP. Our results indicate that rats readily developed CPP to palatable food, which was blocked by AM251. The CPP induced by regular food was strengthened by eCBs and blocked by AM251. Finally, oleamide, unlike anandamide, induced CPP. These results showed that eCBs mediate the positive valence (CPP) of the emotion associated to food ingestion. It was also observed that the blockade of the CB1 receptor causes a loss of correlation between food and CPP (negative valence: avoidance). These data further support the role of eCBs as regulators of the hedonic value of food.
Collapse
Affiliation(s)
- Mónica Méndez-Díaz
- Grupo de Neurociencias, Laboratorio de Canabinoides, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico.
| | | | | | | |
Collapse
|
21
|
Strack AM, Nicolich S, Faidley T, Achanfuo-Yeboah J, Cunningham PK, Hora D, Thompson D, Hickey G, Johnson-Levonas AO, Fong TM, Heymsfield SB. Cannabinoid-1 receptor inhibition prevents the reduction of 24-hour energy expenditure with weight loss. Metabolism 2012; 61:546-53. [PMID: 22001334 DOI: 10.1016/j.metabol.2011.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 08/15/2011] [Accepted: 09/06/2011] [Indexed: 11/15/2022]
Abstract
Pharmacologic inhibition of the cannabinoid-1 receptor (CB1R) in rodent models leads to weight loss and time-dependent changes in energy balance. This study evaluated the effects of CB1R inhibition on weight loss, energy expenditure (EE), and food intake (FI) in an obese canine model following 4 weeks of treatment. Eighteen maintenance-fed obese beagles were evenly and randomly allocated to a CB1R inverse agonist (AM251) (2 mg/kg), a 70% food-restricted (FR) diet, or a control group (C). Evaluations included body weight and composition (dual-energy x-ray absorptiometry scan), EE (doubly labeled water), and FI. Change in body mass at week 4 was significantly greater (P < .050) in the AM251 (-1476.7 g) and FR groups (-1100.0 g) than in the C group (-228.3 g). Food intake was decreased from week 2 onward in the FR and AM251 groups (P < .05). Absolute and lean mass-adjusted EEs were decreased only in the FR group (P < .01); EE in the AM251 group was greater (P < .05) than that in the FR group. Pharmacologic inhibition of CB1R in a canine model led to sustained effects on FI and EE. Weight loss was greater with AM251 than could be accounted for by food restriction (∼25%), an effect likely mediated by the EE response to CB1R inhibition.
Collapse
|
22
|
Abstract
This paper is the 32nd consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2009 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity and neurophysiology (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); and immunological responses (Section 17).
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, 65-30 Kissena Blvd., Flushing, NY 11367, USA.
| |
Collapse
|
23
|
Behavioural satiety sequence (BSS): Separating wheat from chaff in the behavioural pharmacology of appetite. Pharmacol Biochem Behav 2010; 97:3-14. [DOI: 10.1016/j.pbb.2010.03.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 02/15/2010] [Accepted: 03/02/2010] [Indexed: 11/18/2022]
|
24
|
AM 251 differentially effects food-maintained responding depending on food palatability. Pharmacol Biochem Behav 2010; 95:443-8. [PMID: 20331999 DOI: 10.1016/j.pbb.2010.03.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 03/01/2010] [Accepted: 03/13/2010] [Indexed: 11/22/2022]
Abstract
Ligands functioning as antagonists and inverse agonists at the cannabinoid CB(1)-receptor (e.g., AM 251, AM 281, and rimonabant (previously identified as SR141716)) have been demonstrated to have effects on satiety, consumption of, and the motivation to work for, or obtain food. These represent behavioral effects that may also be linked to characteristics such as food palatability or motivation to obtain food. Given the recent removal of rimonabant from clinical trials, a thorough characterization of ingestive behaviors that are associated with other likely candidate drugs is warranted. In the present study, normal weight male Long Evans rats were trained to respond for grain or chocolate-flavored food pellets under progressive-ratio schedules of reinforcement. Rats received acute injections of the CB(1) receptor antagonist AM 251 (0.3-3.0 mg/kg) or vehicle prior to daily testing sessions. Administration of AM 251 produced significant dose-dependent reductions in responding for, deliveries of, and break points (BP) associated with chocolate-flavored but not grain pellets. These data add to the literature demonstrating the ability of CB(1) antagonists to selectively reduce motivation to obtain highly palatable reinforcers.
Collapse
|
25
|
Abstract
Obesity and binge eating disorder are detrimental health conditions that are associated with lower qualities of life. Individuals with obesity often face societal discrimination and frequently experience related medical disorders such as diabetes, hypertension, and hyperlipidemia. Current research suggests neurobiological similarities between obesity, binge eating disorder, and substance dependence. In addition, behavioral similarities link the two conditions; obese and substance dependent individuals often report similar features such as loss of control towards food or substances, respectively, and cravings. Treatment options for obesity have begun to use this information to formulate pharmacological and therapeutic interventions that may provide greater results for weight loss and decreased binge frequency. Similarly, treatment approaches to substance addictions should consider aspects of weight management. Findings from research and treatment studies are presented with the aim of reviewing the current literature of obesity within the context of an addiction framework and providing information on empirically supported approaches to the treatment of co-occurring obesity and substance addiction.
Collapse
Affiliation(s)
- Katherine A. VanBuskirk
- Department of Psychiatry, Yale University School of Medicine, 2 Church Street South, Suite 215, New Haven, CT, 06519, USA
| | - Marc N. Potenza
- Departments of Psychiatry and Child Study Center, Yale University School of Medicine, Connecticut Mental Health Center, 34 Park Street, New Haven, CT, 06519, USA
| |
Collapse
|
26
|
A clinical trial assessing the safety and efficacy of taranabant, a CB1R inverse agonist, in obese and overweight patients: a high-dose study. Int J Obes (Lond) 2010; 34:919-35. [PMID: 20157323 DOI: 10.1038/ijo.2010.21] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To evaluate the efficacy, safety and tolerability of taranabant in obese and overweight patients. DESIGN Double-blind, randomized, placebo-controlled study. SUBJECTS Patients were >or=18 years old, with body mass index of 27-43 kg m(-2), and 51% with metabolic syndrome (MS) randomized to placebo (N=417) or taranabant 2 mg (N=414), 4 mg (N=415) or 6 mg (N=1256) for 104 weeks. MEASUREMENTS Key efficacy measurements included body weight, waist circumference (WC), lipid and glycemic end points. RESULTS On the basis of risk/benefit assessments, the 6-mg dose was discontinued during year 1 (patients on 6 mg were down-dosed to 2 mg or placebo) and the 4-mg dose was discontinued during year 2 (patients on 4 mg were down-dosed to 2 mg). Changes from baseline in body weight at week 52 (all-patients-treated population, last observation carried forward analysis) were -2.6, -6.6 and -8.1 kg, respectively, for placebo and taranabant 2 and 4 mg (both doses P<0.001 vs placebo). For patients who completed year 1, changes from baseline in body weight at week 104 were -1.4, -6.4 and -7.6 kg for placebo and taranabant 2 and 4 mg, respectively (both doses P<0.001 vs placebo). The proportions of patients at weeks 52 and 104 who lost at least 5 and 10% of their baseline body weight were significantly higher and the proportions of patients who met criteria for MS were significantly lower for taranabant 2 and 4 mg vs placebo. The incidence of adverse experiences classified in the gastrointestinal, nervous, psychiatric, cutaneous and vascular organ systems were generally observed to be dose related with taranabant vs placebo. CONCLUSION Taranabant at the 2- and 4-mg dose was effective in achieving clinically significant weight loss over 2 years and was associated with dose-related increases in adverse experiences. On the basis of these and other data, an assessment was made that the overall safety and efficacy profile of taranabant did not support its further development for the treatment of obesity.
Collapse
|
27
|
Tallett AJ, Blundell JE, Rodgers RJ. Effects of acute low-dose combined treatment with rimonabant and sibutramine on appetite and weight gain in rats. Pharmacol Biochem Behav 2009; 97:92-100. [PMID: 20026165 DOI: 10.1016/j.pbb.2009.12.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 10/16/2009] [Accepted: 12/14/2009] [Indexed: 12/13/2022]
Abstract
In view of its potential advantages, drug polytherapy is currently attracting significant interest in the field of obesity research. In this context, concurrent manipulation of serotonergic and cannabinoid pathways in rodents has been found to reduce food and fluid intake in both an additive or synergistic manner. To further assess the value of this polytherapeutic approach, the current study examined the acute effects of low-dose combinations of the cannabinoid CB1 receptor antagonist/inverse agonist rimonabant (0.5 mg/kg) and the dual serotonin- and noradrenaline-reuptake inhibitor sibutramine (0.125 and 0.25 mg/kg) in male rats. Ethological analysis was used to generate comprehensive behavioural profiles, including the behavioural satiety sequence (BSS). Findings confirmed that, although neither drug given alone significantly altered food intake, feeding behaviour or weight gain, rimonabant per se tended to reduce consumption and time spent feeding while significantly increasing scratching and grooming responses. However, none of these effects of the CB1 receptor antagonist/inverse agonist was significantly altered by the presence of either dose of sibutramine. In striking contrast to recent reports of acute low-dose interactions (enhanced appetite suppression and reduced side-effects) between rimonabant and naloxone, present results would not appear to support the clinical potential of rimonabant/sibutramine polytherapy for obesity.
Collapse
Affiliation(s)
- A J Tallett
- Institute of Psychological Sciences, University of Leeds, Leeds, UK
| | | | | |
Collapse
|
28
|
Tallett A, Blundell J, Rodgers R. Sibutramine-induced anorexia: Potent, dose-dependent and behaviourally-selective profile in male rats. Behav Brain Res 2009; 198:359-65. [DOI: 10.1016/j.bbr.2008.11.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Revised: 11/06/2008] [Accepted: 11/09/2008] [Indexed: 01/08/2023]
|
29
|
Night and day: diurnal differences in the behavioural satiety sequence in male rats. Physiol Behav 2009; 97:125-30. [PMID: 19419667 DOI: 10.1016/j.physbeh.2009.01.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2008] [Revised: 01/20/2009] [Accepted: 01/27/2009] [Indexed: 11/20/2022]
Abstract
The behavioural satiety sequence (BSS) is an important method for assessing the selectivity of treatment (physiological, pharmacological and/or genetic) effects on food intake in rodents. The concept describes the natural progression from feeding to resting, with the transition between the two a useful biomarker of behavioural satiety. Although treatments can accelerate (anorexigenics) or delay (orexigenics) this transition without disrupting behavioural structure, the detection of such changes depends upon the timing of the transition under control conditions. Fasting and presatiation are known to affect this timing. However, recent observations in our laboratory have suggested that phase of testing (light or dark) might also be an important consideration. The present study therefore directly compared food intake and the BSS in thoroughly habituated male rats maintained either on a normal light cycle and tested during the light phase or on a reversed light cycle and tested during the dark phase. The results show that phase of testing had relatively little impact on food intake or diverse measures of ingestive and non-ingestive behaviour. Although modest differences were detected in locomotion, grooming and scratching (higher in dark phase), by far the largest difference concerned resting behaviour which had both a later onset and a much lower peak level during dark phase testing. Importantly, these behavioural differences delayed the transition between eating and resting. The potential contribution of diurnal differences in rate of eating is discussed as are the implications of these findings for future studies on the neurobiology of feeding behaviour.
Collapse
|