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Zhao S, Gu ZL, Yue YN, Zhang X, Dong Y. Cannabinoids and monoaminergic system: implications for learning and memory. Front Neurosci 2024; 18:1425532. [PMID: 39206116 PMCID: PMC11349573 DOI: 10.3389/fnins.2024.1425532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 07/26/2024] [Indexed: 09/04/2024] Open
Abstract
Cannabinoids and the endocannabinoid system (ECS) have been intensively studied for their neuroregulatory roles in the central nervous system (CNS), especially in regulating learning and memory. However, many experimental and clinical studies obtained conflicting results indicating a complex network of interaction underlying the regulation of learning and memory by different cannabinoids and the ECS. The ECS influences neuronal synaptic communications, and therefore may exert different regulation via their different impact on other neurotransmitters. The monoaminergic system includes a variety of neurotransmitters, such as dopamine, norepinephrine, and serotonin, which play important roles in regulating mood, cognition, and reward. The interaction among cannabinoids, ECS and the monoaminergic system has drawn particular attention, especially their contributions to learning and memory. In this review, we summarized the current understanding of how cannabinoids, ECS and the monoaminergic system contribute to the process of learning and memory, and discussed the influences of monoaminergic neurotransmission by cannabinoids and ECS during this process.
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Affiliation(s)
- Sha Zhao
- Neuropsychiatry Research Institute, The Affiliated Hospital of Qingdao University, Qingdao, China
- School of Basic Medicine, Qingdao University, Qingdao, China
| | - Zhao-Liang Gu
- Department of Anesthesiology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Ya-Nan Yue
- Neuropsychiatry Research Institute, The Affiliated Hospital of Qingdao University, Qingdao, China
- School of Basic Medicine, Qingdao University, Qingdao, China
| | - Xia Zhang
- Neuropsychiatry Research Institute, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yuan Dong
- Neuropsychiatry Research Institute, The Affiliated Hospital of Qingdao University, Qingdao, China
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Castle ME, Flanigan ME. The role of brain serotonin signaling in excessive alcohol consumption and withdrawal: A call for more research in females. Neurobiol Stress 2024; 30:100618. [PMID: 38433994 PMCID: PMC10907856 DOI: 10.1016/j.ynstr.2024.100618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 02/01/2024] [Accepted: 02/14/2024] [Indexed: 03/05/2024] Open
Abstract
Alcohol Use Disorder (AUD) is a leading cause of death and disability worldwide, but current treatments are insufficient in fully addressing the symptoms that often lead to relapses in alcohol consumption. The brain's serotonin system has been implicated in AUD for decades and is a major regulator of stress-related behaviors associated with increased alcohol consumption. This review will discuss the current literature on the association between neurobiological adaptations in serotonin systems and AUD in humans as well as the effectiveness of serotonin receptor manipulations on alcohol-related behaviors like consumption and withdrawal. We will further discuss how these findings in humans relate to findings in animal models, including a comparison of systemic pharmacological manipulations modulating alcohol consumption. We next provide a detailed overview of brain region-specific roles for serotonin and serotonin receptor signaling in alcohol-related behaviors in preclinical animal models, highlighting the complexity of forming a cohesive model of serotonin function in AUD and providing possible avenues for more effective therapeutic intervention. Throughout the review, we discuss what is known about sex differences in the sequelae of AUD and the role of serotonin in these sequelae. We stress a critical need for additional studies in women and female animals so that we may build a clearer path to elucidating sex-specific serotonergic mechanisms and develop better treatments.
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Affiliation(s)
- Megan E. Castle
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, 27599, USA
| | - Meghan E. Flanigan
- Bowles Center for Alcohol Studies, University of North Carolina School of Medicine, Chapel Hill, NC, 27599, USA
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3
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Cáceres D, Ochoa M, González-Ortiz M, Bravo K, Eugenín J. Effects of Prenatal Cannabinoids Exposure upon Placenta and Development of Respiratory Neural Circuits. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1428:199-232. [PMID: 37466775 DOI: 10.1007/978-3-031-32554-0_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Cannabis use has risen dangerously during pregnancy in the face of incipient therapeutic use and a growing perception of safety. The main psychoactive compound of the Cannabis sativa plant is the phytocannabinoid delta-9-tetrahydrocannabinol (A-9 THC), and its status as a teratogen is controversial. THC and its endogenous analogues, anandamide (AEA) and 2-AG, exert their actions through specific receptors (eCBr) that activate intracellular signaling pathways. CB1r and CB2r, also called classic cannabinoid receptors, together with their endogenous ligands and the enzymes that synthesize and degrade them, constitute the endocannabinoid system. This system is distributed ubiquitously in various central and peripheral tissues. Although the endocannabinoid system's most studied role is controlling the release of neurotransmitters in the central nervous system, the study of long-term exposure to cannabinoids on fetal development is not well known and is vital for understanding environmental or pathological embryo-fetal or postnatal conditions. Prenatal exposure to cannabinoids in animal models has induced changes in placental and embryo-fetal organs. Particularly, cannabinoids could influence both neural and nonneural tissues and induce embryo-fetal pathological conditions in critical processes such as neural respiratory control. This review aims at the acute and chronic effects of prenatal exposure to cannabinoids on placental function and the embryo-fetal neurodevelopment of the respiratory pattern. The information provided here will serve as a theoretical framework to critically evaluate the teratogen effects of the consumption of cannabis during pregnancy.
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Affiliation(s)
- Daniela Cáceres
- Laboratorio de Sistemas Neurales, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Martín Ochoa
- Laboratorio de Sistemas Neurales, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
| | - Marcelo González-Ortiz
- Laboratorio de Investigación Materno-Fetal (LIMaF), Departamento de Obstetricia y Ginecología, Facultad de Medicina, Universidad de Concepción, Concepción, Chile
| | - Karina Bravo
- Laboratorio de Sistemas Neurales, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile
- Facultad de Ingeniería, Universidad Autónoma de Chile, Providencia, Chile
| | - Jaime Eugenín
- Laboratorio de Sistemas Neurales, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Santiago, Chile.
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Abstract
BACKGROUND 5-Methoxy-N,N-dimethyltryptamine (5-MeO-DMT) is a naturally occurring, short-acting psychedelic tryptamine, produced by a variety of plant and animal species. Plants containing 5-MeO-DMT have been used throughout history for ritual and spiritual purposes. The aim of this article is to review the available literature about 5-MeO-DMT and inform subsequent clinical development. METHODS We searched PubMed database for articles about 5-MeO-DMT. Search results were cross-checked against earlier reviews and reference lists were hand searched. Findings were synthesised using a narrative synthesis approach. This review covers the pharmacology, chemistry and metabolism of 5-MeO-DMT, as well epidemiological studies, and reported adverse and beneficial effects. RESULTS 5-MeO-DMT is serotonergic agonist, with highest affinity for 5-HT1A receptors. It was studied in a variety of animal models, but clinical studies with humans are lacking. Epidemiological studies indicate that, like other psychedelics, 5-MeO-DMT induces profound alterations in consciousness (including mystical experiences), with potential beneficial long-term effects on mental health and well-being. CONCLUSION 5-MeO-DMT is a potentially useful addition to the psychedelic pharmacopoeia because of its short duration of action, relative lack of visual effects and putatively higher rates of ego-dissolution and mystical experiences. We conclude that further clinical exploration is warranted, using similar precautions as with other classic psychedelics.
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Affiliation(s)
- Anna O Ermakova
- Beckley Psytech, Beckley, UK
- Psychedelic Trials Group, Centre for Affective Disorders, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | | | - James Rucker
- Psychedelic Trials Group, Centre for Affective Disorders, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Matthew W Johnson
- Department of Psychiatry and Behavioral Sciences, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
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Hempel B, Xi ZX. Receptor mechanisms underlying the CNS effects of cannabinoids: CB 1 receptor and beyond. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2021; 93:275-333. [PMID: 35341569 PMCID: PMC10709991 DOI: 10.1016/bs.apha.2021.10.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Cannabis legalization continues to progress in many US states and other countries. Δ9-tetrahydrocannabinol (Δ9-THC) is the major psychoactive constituent in cannabis underlying both its abuse potential and the majority of therapeutic applications. However, the neural mechanisms underlying cannabis action are not fully understood. In this chapter, we first review recent progress in cannabinoid receptor research, and then examine the acute CNS effects of Δ9-THC or other cannabinoids (WIN55212-2) with a focus on their receptor mechanisms. In experimental animals, Δ9-THC or WIN55212-2 produces classical pharmacological effects (analgesia, catalepsy, hypothermia, hypolocomotion), biphasic changes in affect (reward vs. aversion, anxiety vs. anxiety relief), and cognitive deficits (spatial learning and memory, short-term memory). Accumulating evidence indicates that activation of CB1Rs underlies the majority of Δ9-THC or WIN55121-2's pharmacological and behavioral effects. Unexpectedly, glutamatergic CB1Rs preferentially underlie cannabis action relative to GABAergic CB1Rs. Functional roles for CB1Rs expressed on astrocytes and mitochondria have also been uncovered. In addition, Δ9-THC or WIN55212-2 is an agonist at CB2R, GPR55 and PPARγ receptors and recent studies implicate these receptors in a number of their CNS effects. Other receptors (such as serotonin, opioid, and adenosine receptors) also modulate Δ9-THC's actions and their contributions are detailed. This chapter describes the neural mechanisms underlying cannabis action, which may lead to new discoveries in cannabis-based medication development for the treatment of cannabis use disorder and other human diseases.
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Affiliation(s)
- Briana Hempel
- Addiction Biology Unit, Molecular Targets and Medications Discovery Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD, United States
| | - Zheng-Xiong Xi
- Addiction Biology Unit, Molecular Targets and Medications Discovery Branch, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD, United States.
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Vaseghi S, Arjmandi-Rad S, Nasehi M, Zarrindast MR. Cannabinoids and sleep-wake cycle: The potential role of serotonin. Behav Brain Res 2021; 412:113440. [PMID: 34216647 DOI: 10.1016/j.bbr.2021.113440] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 05/28/2021] [Accepted: 06/25/2021] [Indexed: 02/06/2023]
Abstract
Cannabis sativa (Marijuana) has a long history as a medicinal plant and Δ9-tetrahydrocannabinol (Δ9-THC) is the most active component in this plant. Cannabinoids are interesting compounds with various modulatory effects on physiological processes and cognitive functions. The use of cannabinoids is a double-edged sword, because they induce both adverse and therapeutic properties. One of the most important roles of cannabinoids is modulating sleep-wake cycle. Sleep, its cycle, and its mechanism are highly unknown. Also, the effects of cannabinoids on sleep-wake cycle are so inconsistent. Thus, understanding the role of cannabinoids in modulating sleep-wake cycle is a critical scientific goal. Cannabinoids interact with many neurotransmitter systems. In this review article, we chose serotonin due to its important role in regulating sleep-wake cycle. We found that the interaction between cannabinoids and serotonergic signaling especially in the dorsal raphe is extensive, unknown, and controversial.
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Affiliation(s)
- Salar Vaseghi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Department of Cognitive Neuroscience, Institute for Cognitive Science Studies (ICSS), Tehran, Iran.
| | - Shirin Arjmandi-Rad
- Institute for Cognitive & Brain Sciences, Shahid Beheshti University, Tehran, Iran
| | - Mohammad Nasehi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Mohammad-Reza Zarrindast
- Department of Cognitive Neuroscience, Institute for Cognitive Science Studies (ICSS), Tehran, Iran; Department of Pharmacology School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Peters KZ, Cheer JF, Tonini R. Modulating the Neuromodulators: Dopamine, Serotonin, and the Endocannabinoid System. Trends Neurosci 2021; 44:464-477. [PMID: 33674134 DOI: 10.1016/j.tins.2021.02.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 12/04/2020] [Accepted: 02/01/2021] [Indexed: 12/23/2022]
Abstract
Dopamine (DA), serotonin (5-hydroxytryptamine, 5-HT), and endocannabinoids (ECs) are key neuromodulators involved in many aspects of motivated behavior, including reward processing, reinforcement learning, and behavioral flexibility. Among the longstanding views about possible relationships between these neuromodulators is the idea of DA and 5-HT acting as opponents. This view has been challenged by emerging evidence that 5-HT supports reward seeking via activation of DA neurons in the ventral tegmental area. Adding an extra layer of complexity to these interactions, the endocannabinoid system is uniquely placed to influence dopaminergic and serotonergic neurotransmission. In this review we discuss how these three neuromodulatory systems interact at the cellular and circuit levels. Technological advances that facilitate precise identification and control of genetically targeted neuronal populations will help to achieve a better understanding of the complex relationship between these essential systems, and the potential relevance for motivated behavior.
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Affiliation(s)
- Kate Z Peters
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, 20 Penn Street, Baltimore, MD, USA.
| | - Joseph F Cheer
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, 20 Penn Street, Baltimore, MD, USA; Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA; Program in Neuroscience, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Raffaella Tonini
- Neuromodulation of Cortical and Subcortical Circuits Laboratory, Fondazione Istituto Italiano di Tecnologia, via Morego 30, Genova, Italy.
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Colangeli R, Teskey GC, Di Giovanni G. Endocannabinoid-serotonin systems interaction in health and disease. PROGRESS IN BRAIN RESEARCH 2021; 259:83-134. [PMID: 33541682 DOI: 10.1016/bs.pbr.2021.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Endocannabinoid (eCB) and serotonin (5-HT) neuromodulatory systems work both independently and together to finely orchestrate neuronal activity throughout the brain to strongly sculpt behavioral functions. Surprising parallelism between the behavioral effects of 5-HT and eCB activity has been widely reported, including the regulation of emotional states, stress homeostasis, cognitive functions, food intake and sleep. The distribution pattern of the 5-HT system and the eCB molecular elements in the brain display a strong overlap and several studies report a functional interplay and even a tight interdependence between eCB/5-HT signaling. In this review, we examine the available evidence of the interaction between the eCB and 5-HT systems. We first introduce the eCB system, then we describe the eCB/5-HT crosstalk at the neuronal and synaptic levels. Finally, we explore the potential eCB/5-HT interaction at the behavioral level with the implication for psychiatric and neurological disorders. The precise elucidation of how this neuromodulatory interaction dynamically regulates biological functions may lead to the development of more targeted therapeutic strategies for the treatment of depressive and anxiety disorders, psychosis and epilepsy.
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Affiliation(s)
- Roberto Colangeli
- Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy; Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.
| | - G Campbell Teskey
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom
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Ibarra-Lecue I, Diez-Alarcia R, Urigüen L. Serotonin 2A receptors and cannabinoids. PROGRESS IN BRAIN RESEARCH 2021; 259:135-175. [PMID: 33541675 DOI: 10.1016/bs.pbr.2021.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Accumulating evidence has proven that both exogenous cannabinoids as well as imbalances in the endocannabinoid system are involved in the onset and development of mental disorders such as anxiety, depression, or schizophrenia. Extensive recent research in this topic has mainly focused on the molecular mechanisms by which cannabinoid agonists may contribute to the pathophysiology of these disorders. Initially, serotonin neurotransmitter garnered most attention due to its relationship to mood disorders and mental diseases, with little attention to specific receptors. To date, the focus has redirected toward the understanding of different serotonin receptors, through a demonstration of its versatile pharmacology and synergy with different modulators. Serotonin 2A receptors are a good example of this phenomenon, and the complex signaling that they trigger appears of high relevance in the context of mental disorders, especially in schizophrenia. This chapter will analyze most relevant attributes of serotonin 2A receptors and the endocannabinoid system, and will highlight the evidence toward the functional bidirectional interaction between these elements in the brain as well as the impact of the endocannabinoid system dysregulation on serotonin 2A receptors functionality.
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Affiliation(s)
- Inés Ibarra-Lecue
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain; Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, Madrid, Spain
| | - Rebeca Diez-Alarcia
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain; Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, Madrid, Spain; Biocruces Bizkaia Health Research Institute, Bizkaia, Spain
| | - Leyre Urigüen
- Department of Pharmacology, University of the Basque Country, UPV/EHU, Leioa, Spain; Centro de Investigación Biomédica en Red de Salud Mental CIBERSAM, Madrid, Spain; Biocruces Bizkaia Health Research Institute, Bizkaia, Spain.
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Escartín Pérez RE, Mancilla Díaz JM, Cortés Salazar F, López Alonso VE, Florán Garduño B. CB1/5-HT/GABA interactions and food intake regulation. PROGRESS IN BRAIN RESEARCH 2021; 259:177-196. [PMID: 33541676 DOI: 10.1016/bs.pbr.2021.01.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Despite historically the serotonergic, GABAergic, and cannabinoid systems have been shown to play a crucial role in the central regulation of eating behavior, interest in the study of the interactions of these neurotransmission systems has only now been investigated. Current evidence suggests that serotonin may influence normal and pathological eating behavior in significantly more complex ways than was initially thought. This knowledge has opened the possibility of exploring the potential clinical utility of new therapeutic strategies more effective and safer than the current approaches to treat pathological eating behavior. Furthermore, the nature and complexity of the interactions between these neurotransmitter systems have provided a better understanding of the pathophysiological mechanisms not only of eating behavior and eating disorders but also of some of the comorbidities associated with modulation of cortical circuits, which are involved in high order cognitive processes. Accordingly, in the present chapter, the clinical and experimental findings of the interactions between serotonin, GABA, and cannabinoids are synthesized, emphasizing the pharmacological, neurophysiological, and neuroanatomical aspects that could potentially improve the current therapeutic approaches against pathological eating behavior.
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Affiliation(s)
- Rodrigo Erick Escartín Pérez
- Facultad de Estudios Superiores Iztacala, División de Investigación y Posgrado, Laboratorio de Neurobiología de la Alimentación, Universidad Nacional Autónoma de México, México, México.
| | - Juan Manuel Mancilla Díaz
- Facultad de Estudios Superiores Iztacala, División de Investigación y Posgrado, Laboratorio de Neurobiología de la Alimentación, Universidad Nacional Autónoma de México, México, México
| | - Felipe Cortés Salazar
- Facultad de Estudios Superiores Iztacala, División de Investigación y Posgrado, Laboratorio de Neurobiología de la Alimentación, Universidad Nacional Autónoma de México, México, México
| | - Verónica Elsa López Alonso
- Facultad de Estudios Superiores Iztacala, División de Investigación y Posgrado, Laboratorio de Neurobiología de la Alimentación, Universidad Nacional Autónoma de México, México, México
| | - Benjamín Florán Garduño
- Facultad de Estudios Superiores Iztacala, División de Investigación y Posgrado, Laboratorio de Neurobiología de la Alimentación, Universidad Nacional Autónoma de México, México, México
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Nocheva H, Sabit Z, Bakalov D, Grigorov E. Interactions between the cannabinoid and the serotonergic systems in modulation of pain perception. PHARMACIA 2021. [DOI: 10.3897/pharmacia.68.e49219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of our study was to evaluate the effects of cannabinoids and serotonergic system on nociception in intact rats and after heat stress. Cannabinoid receptor type 1 (CB1) and 5-hydroxytryptamine receptor (5НТ1А) agonists and antagonists have been administered according to different experimental designs (alone and in combinations) in intact male Wistar rats, as well in animals subjected to one hour of heat stress. Pain perception has been evaluated by Paw pressure test. Our results pointed out that cannabinoids and the serotonergic system interact in nociception in intact animals as well as after heat stress. Cannabinoids seemed to have less prominent role in such interaction in intact animals than after heat stress. The interplay between the two systems probably involves different mechanisms in intact animals and after heat stress with time-dependent effects. The interaction between the cannabinoid and the serotonergic systems exerts a modulating rather than mediating effect on h-SIA.
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Modulation of Noradrenergic and Serotonergic Systems by Cannabinoids: Electrophysiological, Neurochemical and Behavioral Evidence. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1297:111-132. [PMID: 33537940 DOI: 10.1007/978-3-030-61663-2_8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The main noradrenergic and serotonergic nuclei in the central nervous system (CNS) are the locus coeruleus (LC) and the dorsal raphe nucleus (DRN). These brain areas, located in the brainstem, play a pivotal role in the control of various functions and behaviors that are altered by cannabinoids (i.e., pain, arousal, mood, anxiety, or sleep-wake cycle). Anatomical, neurochemical, and functional data suggest that cannabinoids regulate both central noradrenergic and serotonergic neurotransmission. Thus, strong evidence has shown that the firing activity of LC and DRN monoamine neurons or the synthesis/release of noradrenaline (NA) and serotonin (5-HT) in the projection areas are all affected by cannabinoid administration. Herein, we propose that interaction between the endocannabinoid system and the noradrenergic-serotonergic systems could account for some of the anxiolytic, antidepressant, and antinociceptive effects of cannabinoids or the disruption of attention/sleep induced by these drugs.
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Vaseghi S, Nasehi M, Zarrindast MR. How do stupendous cannabinoids modulate memory processing via affecting neurotransmitter systems? Neurosci Biobehav Rev 2020; 120:173-221. [PMID: 33171142 DOI: 10.1016/j.neubiorev.2020.10.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/17/2020] [Accepted: 10/26/2020] [Indexed: 12/27/2022]
Abstract
In the present study, we wanted to review the role of cannabinoids in learning and memory in animal models, with respect to their interaction effects with six principal neurotransmitters involved in learning and memory including dopamine, glutamate, GABA (γ-aminobutyric acid), serotonin, acetylcholine, and noradrenaline. Cannabinoids induce a wide-range of unpredictable effects on cognitive functions, while their mechanisms are not fully understood. Cannabinoids in different brain regions and in interaction with different neurotransmitters, show diverse responses. Previous findings have shown that cannabinoids agonists and antagonists induce various unpredictable effects such as similar effect, paradoxical effect, or dualistic effect. It should not be forgotten that brain neurotransmitter systems can also play unpredictable roles in mediating cognitive functions. Thus, we aimed to review and discuss the effect of cannabinoids in interaction with neurotransmitters on learning and memory. In addition, we mentioned to the type of interactions between cannabinoids and neurotransmitter systems. We suggested that investigating the type of interactions is a critical neuropharmacological issue that should be considered in future studies.
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Affiliation(s)
- Salar Vaseghi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran; Department of Cognitive Neuroscience, Institute for Cognitive Science Studies (ICSS), Tehran, Iran
| | - Mohammad Nasehi
- Cognitive and Neuroscience Research Center (CNRC), Amir-Almomenin Hospital, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
| | - Mohammad-Reza Zarrindast
- Department of Cognitive Neuroscience, Institute for Cognitive Science Studies (ICSS), Tehran, Iran; Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
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Baltz JW, Le LT. Serotonin Syndrome versus Cannabis Toxicity in the Emergency Department. Clin Pract Cases Emerg Med 2020; 4:171-173. [PMID: 32426664 PMCID: PMC7220016 DOI: 10.5811/cpcem.2020.1.45410] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 01/13/2020] [Accepted: 01/23/2020] [Indexed: 11/21/2022] Open
Abstract
As more states legalize marijuana, the potential of marijuana abuse could lead to an increase in the number of emergency department (ED) visits. We describe two patients who presented to the ED with dilated pupils, rigidity in both lower extremities, and clonus in both feet after inhaling the vapor of a highly potent form of marijuana. Serotonin syndrome diagnosis was initially considered in the differential diagnosis. Ultimately, high-potency marijuana abuse was the final diagnosis. Therefore, marijuana toxicity should be considered in ED patients who present with signs and symptoms similar to that of serotonin syndrome.
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Affiliation(s)
- Jacob W Baltz
- CoxHealth System, Department of Emergency Medicine, Springfield, Missouri
| | - Lamanh T Le
- CoxHealth System, Department of Pharmacy, Springfield, Missouri
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Cohen K, Mama Y, Rosca P, Pinhasov A, Weinstein A. Chronic Use of Synthetic Cannabinoids Is Associated With Impairment in Working Memory and Mental Flexibility. Front Psychiatry 2020; 11:602. [PMID: 32695029 PMCID: PMC7339911 DOI: 10.3389/fpsyt.2020.00602] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 06/10/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND We have recently shown that chronic use of Synthetic Cannabinoids (SCs) has been associated with mood disorders and impairments in executive functions. There is also evidence indicating that chronic SC users have higher rates of comorbidity with depression and psychotic symptoms. Here, we investigate performance on executive function and emotional processing tasks in regular SC users and a measure of schizotypal traits. METHOD Thirty chronic SC users, 32 recreational cannabis users, and 32 non-using control participants, without history of mental disorder, or current substance abuse diagnosis (mean age 26 ± 4.27 years; 85 males, 9 females), were tested in addiction treatment centers in Israel. Computerized neurocognitive function tests; the N-back task, Go/No-Go task, Wisconsin Sorting Card-like Task (WSCT), and emotional face recognition task and questionnaires of depression, anxiety and schizotypal traits and symptoms were used. RESULTS SC users have performed worse than recreational cannabis users and non-cannabis users on the N-back working-memory task (lower accuracy) and the WSCT cognitive flexibility task. SC users showed greater schizotypal traits and symptoms compared with recreational cannabis users and non-user control participants. A positive association was found in cannabinoid-user groups between schizotypal traits and symptoms and cognitive and emotional processing measures. Finally, SC users have scored higher on depression and state-trait anxiety measures than recreational cannabis users or healthy control participants. CONCLUSIONS Repeated use of SCs is associated with impairment in executive functions and emotional processing. These alterations are associated with depression and schizotypal traits and symptoms. This adds to existing evidence on the long-term consequences of SC drugs and their risks for mental health.
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Affiliation(s)
- Koby Cohen
- Department of Behavioral Science, Ariel University, Ariel, Israel
| | - Yaniv Mama
- Department of Behavioral Science, Ariel University, Ariel, Israel
| | - Paola Rosca
- Ministry of Health (Israel), Jerusalem, Israel
| | - Albert Pinhasov
- Adelson School of Medicine, Ariel University, Ariel, Israel.,Department of Molecular Biology, Ariel University, Ariel, Israel
| | - Aviv Weinstein
- Department of Behavioral Science, Ariel University, Ariel, Israel
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Zhang X, Coates K, Dacks A, Günay C, Lauritzen JS, Li F, Calle-Schuler SA, Bock D, Gaudry Q. Local synaptic inputs support opposing, network-specific odor representations in a widely projecting modulatory neuron. eLife 2019; 8:46839. [PMID: 31264962 PMCID: PMC6660217 DOI: 10.7554/elife.46839] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 07/01/2019] [Indexed: 12/14/2022] Open
Abstract
Serotonin plays different roles across networks within the same sensory modality. Previously, we used whole-cell electrophysiology in Drosophila to show that serotonergic neurons innervating the first olfactory relay are inhibited by odorants (Zhang and Gaudry, 2016). Here we show that network-spanning serotonergic neurons segregate information about stimulus features, odor intensity and identity, by using opposing coding schemes in different olfactory neuropil. A pair of serotonergic neurons (the CSDns) innervate the antennal lobe and lateral horn, which are first and second order neuropils. CSDn processes in the antennal lobe are inhibited by odors in an identity independent manner. In the lateral horn, CSDn processes are excited in an odor identity dependent manner. Using functional imaging, modeling, and EM reconstruction, we demonstrate that antennal lobe derived inhibition arises from local GABAergic inputs and acts as a means of gain control on branch-specific inputs that the CSDns receive within the lateral horn.
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Affiliation(s)
- Xiaonan Zhang
- Department of Biology, University of Maryland, College Park, United States
| | - Kaylynn Coates
- Department of Biology, West Virginia University, Morgantown, United States
| | - Andrew Dacks
- Department of Biology, West Virginia University, Morgantown, United States
| | - Cengiz Günay
- School of Science and Technology, Georgia Gwinnett College, Lawrenceville, United States
| | - J Scott Lauritzen
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Feng Li
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | | | - Davi Bock
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States.,Department of Neurological Sciences, Larner College of Medicine, University of Vermont, Burlington, United States
| | - Quentin Gaudry
- Department of Biology, University of Maryland, College Park, United States
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Cohen K, Weizman A, Weinstein A. Modulatory effects of cannabinoids on brain neurotransmission. Eur J Neurosci 2019; 50:2322-2345. [DOI: 10.1111/ejn.14407] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 03/06/2019] [Accepted: 03/08/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Koby Cohen
- Department of Behavioral Science Ariel University Science Park 40700 Ariel Israel
| | | | - Aviv Weinstein
- Department of Behavioral Science Ariel University Science Park 40700 Ariel Israel
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18
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Colangeli R, Di Maio R, Pierucci M, Deidda G, Casarrubea M, Di Giovanni G. Synergistic action of CB 1 and 5-HT 2B receptors in preventing pilocarpine-induced status epilepticus in rats. Neurobiol Dis 2019; 125:135-145. [PMID: 30716469 DOI: 10.1016/j.nbd.2019.01.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 01/24/2019] [Accepted: 01/31/2019] [Indexed: 11/30/2022] Open
Abstract
Endocannabinoids (eCBs) and serotonin (5-HT) play a neuromodulatory role in the central nervous system. Both eCBs and 5-HT regulate neuronal excitability and their pharmacological potentiation has been shown to control seizures in pre-clinical and human studies. Compelling evidence indicates that eCB and 5-HT systems interact to modulate several physiological and pathological brain functions, such as food intake, pain, drug addiction, depression, and anxiety. Nevertheless, there is no evidence of an eCB/5-HT interaction in experimental and human epilepsies, including status epilepticus (SE). Here, we performed video-EEG recording in behaving rats treated with the pro-convulsant agent pilocarpine (PILO), in order to study the effect of the activation of CB1/5-HT2 receptors and their interaction on SE. Synthetic cannabinoid agonist WIN55,212-2 (WIN) decreased behavioral seizure severity of PILO-induced SE at 2 mg/kg (but not at 1 and 5 mg/kg, i.p.), while 5-HT2B/2C receptor agonist RO60-0175 (RO; 1, 3, 10 mg/kg, i.p.) was devoid of any effect. RO 3 mg/kg was instead capable of potentiating the effect of WIN 2 mg/kg on the Racine scale score. Surprisingly, neither WIN 2 mg/kg nor RO 3 mg/kg had any effect on the incidence and the intensity of EEG seizures when administered alone. However, WIN+RO co-administration reduced the incidence and the severity of EEG SE and increased the latency to SE onset after PILO injection. WIN+RO effects were blocked by the selective CB1R antagonist AM251 and the 5-HT2BR antagonist RS127445, but not by the 5-HT2CR antagonist SB242084 or the 5-HT2AR antagonist MDL11,939. These data revealed a synergistic interaction between CB1R/5-HT2BR in the expression of PILO-induced SE.
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Affiliation(s)
- Roberto Colangeli
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.
| | - Roberto Di Maio
- Pittsburgh Inst. for Neurodegenerative Dis., Dept. of Neurology, Univ. of Pittsburgh, PA, USA
| | - Massimo Pierucci
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Gabriele Deidda
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
| | - Maurizio Casarrubea
- Department of Experimental Biomedicine and Clinical Neurosciences, Human Physiology Section "Giuseppe Pagano", University of Palermo, Palermo, Italy
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; School of Biosciences, Cardiff University, Cardiff, UK.
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Regulation of noradrenergic and serotonergic systems by cannabinoids: relevance to cannabinoid-induced effects. Life Sci 2018; 192:115-127. [DOI: 10.1016/j.lfs.2017.11.029] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 10/29/2017] [Accepted: 11/16/2017] [Indexed: 12/11/2022]
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20
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Hamedinia M, Sharifi M, Hosseini-Kakhak A. The Effect of Eight Weeks of Aerobic, Anaerobic and Resistance Training on some factor of Endocannabinoid System, Serotonin, Beta-Endorphin and BDNF in Young Men. ACTA ACUST UNITED AC 2017. [DOI: 10.13005/bbra/2562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
ABSTRACT: The aim of this study was investigated the effect of eight weeks of aerobic, anaerobic and resistance training on some endocannabinoid, serotonin, beta-endorphin and BDNF agents of young men. Thirty-two young men (19 to 25 years old) who did not have regular physical activity were randomly divided into four groups, and each of them were participated in various sports exercises for eight weeks. A group for aerobic exercises (two exercises with 65-70 maximum heart rate 3 sessions per week), an anaerobic exercise group (two exercises with a maximum intensity of 3 sessions per week), a group for circular resistance exercises (6-8 Station Which is repeated 8-12 times, and for three times a week) and finally a group was selected as a control. ELISA method was used to measure endocannabinoid system, serotonin, beta-endorphin and BDNF factors. The results showed that eight weeks aerobic training significantly increased serotonin levels and eight weeks aerobic and anaerobic exercise significantly increased BDNF. Aerobic, anaerobic, and resistive exercises have no significant effect on arachidonoyl glycerol (2-AG), anandamide(AEA) and beta-endorphin. There was a significant increase in happiness in all three training groups compared to the control group.The results of this study indicated an increase in mediation associated with pleasure and happiness in humans. Concerning the particular effect of long-term exercise on the endocannabinoid system, it is difficult to conclude.
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Affiliation(s)
- Mohammadreza Hamedinia
- Department of Sport Physiology, Faculty of Physical Education and Sports Science, Hakim Sabzevari University, Sabzevar, Iran
| | - Moslem Sharifi
- Department of Sport Physiology, Faculty of Physical Education and Sports Science, Hakim Sabzevari University, Sabzevar, Iran
| | - Alireza Hosseini-Kakhak
- Department of Sport Physiology, Faculty of Physical Education and Sports Science, Hakim Sabzevari University, Sabzevar, Iran
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Nasehi M, Rostam-Nezhad E, Ebrahimi-Ghiri M, Zarrindast MR. Interaction between hippocampal serotonin and cannabinoid systems in reactivity to spatial and object novelty detection. Behav Brain Res 2017; 317:272-278. [DOI: 10.1016/j.bbr.2016.09.059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2016] [Revised: 09/21/2016] [Accepted: 09/25/2016] [Indexed: 12/12/2022]
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22
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Nasehi M, Farrahizadeh M, Ebrahimi-Ghiri M, Zarrindast MR. Modulation of cannabinoid signaling by hippocampal 5-HT4 serotonergic system in fear conditioning. J Psychopharmacol 2016; 30:936-44. [PMID: 27296273 DOI: 10.1177/0269881116652584] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Behavioral studies have suggested a key role for the cannabinoid system in the modulation of conditioned fear memory. Likewise, much of the literature has revealed that the serotonergic system affects Pavlovian fear conditioning and extinction. A high level of functional overlap between the serotonin and cannabinoid systems has also been reported. To clarify the interaction between the hippocampal serotonin (5-HT4) receptor and the cannabinoid CB1 receptor in the acquisition of fear memory, the effects of 5-HT4 agents, arachidonylcyclopropylamide (ACPA; CB1 receptor agonist), and the combined use of these drugs on fear learning were studied in a fear conditioning task in adult male NMRI mice. Pre-training intraperitoneal administration of ACPA (0.1 mg/kg) decreased the percentage of freezing time in both context- and tone-dependent fear conditions, suggesting impairment of the acquisition of fear memory. Pre-training, intra-hippocampal (CA1) microinjection of RS67333, a 5-HT4 receptor agonist, at doses of 0.1 and 0.2 or 0.2 µg/mouse impaired contextual and tone fear memory, respectively. A subthreshold dose of RS67333 (0.005 µg/mouse) did not alter the ACPA response in either condition. Moreover, intra-CA1 microinjection of RS23597 as a 5-HT4 receptor antagonist did not alter context-dependent fear memory acquisition, but it did impair tone-dependent fear memory acquisition. However, a subthreshold dose of the RS23597 (0.01 µg/mouse) potentiated ACPA-induced fear memory impairment in both conditions. Therefore, we suggest that the blockade of hippocampal 5-HT4 serotonergic system modulates cannabinoid signaling induced by the activation of CB1 receptors in conditioned fear.
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MESH Headings
- Aniline Compounds/administration & dosage
- Aniline Compounds/pharmacology
- Animals
- Arachidonic Acids/administration & dosage
- Arachidonic Acids/pharmacology
- Cannabinoid Receptor Agonists/administration & dosage
- Cannabinoid Receptor Agonists/pharmacology
- Cannabinoids/metabolism
- Conditioning, Classical/drug effects
- Dose-Response Relationship, Drug
- Fear/drug effects
- Fear/physiology
- Freezing Reaction, Cataleptic/drug effects
- Freezing Reaction, Cataleptic/physiology
- Hippocampus/metabolism
- Male
- Memory/drug effects
- Memory/physiology
- Mice
- Piperidines/administration & dosage
- Piperidines/pharmacology
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/metabolism
- Receptors, Serotonin, 5-HT4/drug effects
- Receptors, Serotonin, 5-HT4/metabolism
- Serotonin 5-HT4 Receptor Agonists/administration & dosage
- Serotonin 5-HT4 Receptor Agonists/pharmacology
- Serotonin 5-HT4 Receptor Antagonists/administration & dosage
- Serotonin 5-HT4 Receptor Antagonists/pharmacology
- para-Aminobenzoates/administration & dosage
- para-Aminobenzoates/pharmacology
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Affiliation(s)
- Mohammad Nasehi
- Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran
| | - Maryam Farrahizadeh
- Department of Biology, Faculty of Basic Sciences, Islamic Azad University, Northern Branch, Tehran, Iran
| | | | - Mohammad-Reza Zarrindast
- Cognitive and Neuroscience Research Center (CNRC), Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran Department of Pharmacology School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Iranian National Center for Addiction Studies, Tehran University of Medical Sciences, Tehran, Iran Institute for Cognitive Science Studies (ICSS), Tehran, Iran School of Cognitive Sciences, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran Medical Genomics Research Center, Tehran Medical Sciences Branch, Islamic Azad University, Tehran, Iran
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Preclinical studies on the reinforcing effects of cannabinoids. A tribute to the scientific research of Dr. Steve Goldberg. Psychopharmacology (Berl) 2016; 233:1845-66. [PMID: 27026633 PMCID: PMC5073892 DOI: 10.1007/s00213-016-4244-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 02/09/2016] [Indexed: 11/27/2022]
Abstract
RATIONALE The reinforcing effects of most abused drugs have been consistently demonstrated and studied in animal models, although those of marijuana were not, until the demonstration 15 years ago that delta-9-tetrahydrocannabinol (THC) could serve as a reinforcer in self-administration (SA) procedures in squirrel monkeys. Until then, those effects were inferred using indirect assessments. OBJECTIVES The aim of this manuscript is to review the primary preclinical procedures used to indirectly and directly infer reinforcing effects of cannabinoid drugs. METHODS Results will be reviewed from studies of cannabinoid discrimination, intracranial self-stimulation (ICSS), conditioned place preference (CPP), as well as change in levels of dopamine assessed in brain areas related to reinforcement, and finally from self-administration procedures. For each procedure, an evaluation will be made of the predictive validity in detecting the potential abuse liability of cannabinoids based on seminal papers, with the addition of selected reports from more recent years especially those from Dr. Goldberg's research group. RESULTS AND CONCLUSIONS ICSS and CPP do not provide consistent results for the assessment of potential for abuse of cannabinoids. However, drug discrimination and neurochemistry procedures appear to detect potential for abuse of cannabinoids, as well as several novel "designer cannabinoid drugs." Though after 15 years transfer of the self-administration model of marijuana abuse from squirrel monkeys to other species remains somewhat problematic, studies with the former species have substantially advanced the field, and several reports have been published with consistent self-administration of cannabinoid agonists in rodents.
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Abstract
The hippocampus plays an important role in emotional and cognitive processing, and both of these domains are affected in patients with major depressive disorder (MDD). Extensive preclinical research and the notion that modulation of serotonin (5-HT) neurotransmission plays a key role in the therapeutic efficacy of selective serotonin reuptake inhibitors (SSRIs) support the view that 5-HT is important for hippocampal function in normal and disease-like conditions. The hippocampus is densely innervated by serotonergic fibers, and the majority of 5-HT receptor subtypes are expressed there. Furthermore, hippocampal cells often co-express multiple 5-HT receptor subtypes that can have either complementary or opposing effects on cell function, adding to the complexity of 5-HT neurotransmission. Here we review the current knowledge of how 5-HT, through its various receptor subtypes, modulates hippocampal output and the activity of hippocampal pyramidal cells in rodents. In addition, we discuss the relevance of 5-HT modulation for cognitive processing in rodents and possible clinical implications of these results in patients with MDD. Finally, we review the data on how SSRIs and vortioxetine, an antidepressant with multimodal activity, affect hippocampal function, including cognitive processing, from both a preclinical and clinical perspective.
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25
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Molecular Mechanisms of Cannabis Signaling in the Brain. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 137:123-47. [PMID: 26810000 DOI: 10.1016/bs.pmbts.2015.10.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Cannabis has been cultivated and used by humans for thousands of years. Research for decades was focused on understanding the mechanisms of an illegal/addictive drug. This led to the discovery of the vast endocannabinoid system. Research has now shifted to understanding fundamental biological questions related to one of the most widespread signaling systems in both the brain and the body. Our understanding of cannabinoid signaling has advanced significantly in the last two decades. In this review, we discuss the state of knowledge on mechanisms of Cannabis signaling in the brain and the modulation of key brain neurotransmitter systems involved in both brain reward/addiction and psychiatric disorders. It is highly probable that various cannabinoids will be found to be efficacious in the treatment of a number of psychiatric disorders. However, while there is clearly much potential, marijuana has not been properly vetted by the medical-scientific evaluation process and there are clearly a range of potentially adverse side-effects-including addiction. We are at crossroads for research on endocannabinoid function and therapeutics (including the use of exogenous treatments such as Cannabis). With over 100 cannabinoid constituents, the majority of which have not been studied, there is much Cannabis research yet to be done. With more states legalizing both the medicinal and recreational use of marijuana the rigorous scientific investigation into cannabinoid signaling is imperative.
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Nasehi M, Kafi F, Khakpai F, Zarrindast MR. Involvement of the serotonergic system of the ventral hippocampus (CA3) on amnesia induced by ACPA in mice. Behav Brain Res 2015; 286:356-63. [DOI: 10.1016/j.bbr.2015.03.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 02/27/2015] [Accepted: 03/04/2015] [Indexed: 10/23/2022]
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27
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The role of serotonin in drug use and addiction. Behav Brain Res 2014; 277:146-92. [PMID: 24769172 DOI: 10.1016/j.bbr.2014.04.007] [Citation(s) in RCA: 209] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/04/2014] [Accepted: 04/05/2014] [Indexed: 12/26/2022]
Abstract
The use of psychoactive drugs is a wide spread behaviour in human societies. The systematic use of a drug requires the establishment of different drug use-associated behaviours which need to be learned and controlled. However, controlled drug use may develop into compulsive drug use and addiction, a major psychiatric disorder with severe consequences for the individual and society. Here we review the role of the serotonergic (5-HT) system in the establishment of drug use-associated behaviours on the one hand and the transition and maintenance of addiction on the other hand for the drugs: cocaine, amphetamine, methamphetamine, MDMA (ecstasy), morphine/heroin, cannabis, alcohol, and nicotine. Results show a crucial, but distinct involvement of the 5-HT system in both processes with considerable overlap between psychostimulant and opioidergic drugs and alcohol. A new functional model suggests specific adaptations in the 5-HT system, which coincide with the establishment of controlled drug use-associated behaviours. These serotonergic adaptations render the nervous system susceptible to the transition to compulsive drug use behaviours and often overlap with genetic risk factors for addiction. Altogether we suggest a new trajectory by which serotonergic neuroadaptations induced by first drug exposure pave the way for the establishment of addiction.
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Hillard CJ, Liu QS. Endocannabinoid signaling in the etiology and treatment of major depressive illness. Curr Pharm Des 2014; 20:3795-811. [PMID: 24180398 PMCID: PMC4002665 DOI: 10.2174/13816128113196660735] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 10/23/2013] [Indexed: 12/28/2022]
Abstract
The purpose of this review is to examine human and preclinical data that are relevant to the following hypotheses. The first hypothesis is that deficient CB1R-mediated signaling results in symptoms that mimic those seen in depression. The second hypothesis is that activation of CB1R-mediated signaling results in behavioral, endocrine and other effects that are similar to those produced by currently used antidepressants. The third hypothesis is that conventional antidepressant therapies act through enhanced CB1R mediated signaling. Together the available data indicate that activators of CB1R signaling, particularly inhibitors of fatty acid amide hydrolase, should be considered for clinical trials for the treatment of depression.
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MESH Headings
- Animals
- Antidepressive Agents/pharmacology
- Antidepressive Agents/therapeutic use
- Brain/drug effects
- Brain/enzymology
- Brain/metabolism
- Brain/pathology
- Cannabis
- Depressive Disorder, Major/drug therapy
- Depressive Disorder, Major/etiology
- Depressive Disorder, Major/genetics
- Depressive Disorder, Major/pathology
- Disease Models, Animal
- Endocannabinoids/genetics
- Endocannabinoids/metabolism
- Humans
- Magnetic Resonance Imaging
- Neurogenesis/drug effects
- Polymorphism, Genetic
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Signal Transduction/drug effects
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Affiliation(s)
| | - Qing-song Liu
- Neuroscience Research Center, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226.
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Sundaramahalingam M, Ramasundaram S, Rathinasamy SD, Natarajan RP, Somasundaram T. Role of Acorus calamus and alpha-asarone on hippocampal dependent memory in noise stress exposed rats. Pak J Biol Sci 2013; 16:770-778. [PMID: 24498829 DOI: 10.3923/pjbs.2013.770.778] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Stress is a condition or stimulus that threatens an organism's survival. Noise is an environmental stressor. It is well known that long term as well as acute exposure to noise led to oxidative stress. In the present study, it was investigated that the persistence of noise stress (100 dBA/4 h/d for 30 days) could cause memory impairment in rats and whether ethylacetate extract of AC EAAC (50 mg kg(-1) b.wt.) and alpha-Asarone (9 mg kg(-1) b.wt.). treatment can prevent or not. In order to understand the possible mechanism behind it, antioxidant status and acetylcholinesterase (AChE) activity in hippocampus was evaluated after rats were tested in Radial Eight-arm Maze (RAM). Heat shock protein 70 (hsp 70) expression in hippocampus was also evaluated to understand the intensity of stress level. Results showed that after noise stress exposure, time taken to visit all the baited arms, working and reference memory errors were increased in RAM. The superoxide dismutase, lipid peroxidation, AChE activity, hsp 70 were significantly increased with concomitant decrease in catalase, glutathione peroxidase activity and G6PD activity of non-enzymatic levels was observed in the 30 days noise stress exposed group. When rats were co-administrated with EAAC and alpha-Asarone prevents the noise stress induced alterations significantly. In Conclusion, noise stress induced oxidative stress, increased AChE activity, and over expression of hsp 70 in hippocampus region might have led to the impairment of spatial memory. EAAC and alpha-Asarone prevents this noise stress induced memory impairment.
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Affiliation(s)
| | | | - Sheela Devi Rathinasamy
- Department of Physiology, Dr. ALM. PG. Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai-600 113, India
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The role of α₂-adrenoceptors in the anti-convulsant effects of cannabinoids on pentylenetetrazole-induced seizure threshold in mice. Eur J Pharmacol 2013; 714:1-6. [PMID: 23756131 DOI: 10.1016/j.ejphar.2013.05.040] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 05/19/2013] [Accepted: 05/30/2013] [Indexed: 11/22/2022]
Abstract
Cannabinoid system plays a pivotal role in the seizure threshold modulation which is mainly mediated through activation of the cannabinoid CB₁ receptor. There is also several evidence of interaction between cannabinoid system and α₂-adrenoceptors in different paradigms. Using model of clonic seizure induced by intravenous pentylenetetrazole (PTZ) in male mice, we investigated whether α₂-adrenoceptors is involved in the effects of cannabinoids on the seizure threshold. Injection of the selective cannabinoid CB₁ agonist ACEA (2 mg/kg) significantly (P<0.01) increased the seizure threshold which was prevented by pretreatment with the selective CB1 antagonist AM251 (1 mg/kg, i.p.). The highest doses of clonidine, a α₂ receptor agonist, (1 and 5 mg/kg) showed anticonvulsant effects while yohimbine, a α₂ receptor antagonist, (0.01, 0.1, 1, and 10 mg/kg) did not induce any significant effect on PTZ seizure threshold. Pretreatment with clonidine (0.1 and 0.5 mg/kg) significantly reversed the anticonvulsant effect of ACEA (2 mg/kg). Yohimbine (0.1, 1, and 10 mg/kg) pretreatment of mice enhanced the clonic seizure threshold of ACEA (1 mg/kg), significantly. Combination of non-effective doses of AM251 (0.1 mg/kg) and clonidine (0.01 mg/kg) showed additive effect in blocking the anticonvulsant effect of ACEA (2 mg/kg). In conclusion, our findings demonstrated that α₂-adrenoceptors could be involved in the anticonvulsant properties of the specific cannabinoid CB₁ agonist ACEA, suggesting that CB₁ cannabinoid and α₂ receptors have functional interactions in modulation of clonic seizure threshold.
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Maejima T, Masseck OA, Mark MD, Herlitze S. Modulation of firing and synaptic transmission of serotonergic neurons by intrinsic G protein-coupled receptors and ion channels. Front Integr Neurosci 2013; 7:40. [PMID: 23734105 PMCID: PMC3661940 DOI: 10.3389/fnint.2013.00040] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 05/03/2013] [Indexed: 11/13/2022] Open
Abstract
Serotonergic neurons project to virtually all regions of the central nervous system and are consequently involved in many critical physiological functions such as mood, sexual behavior, feeding, sleep/wake cycle, memory, cognition, blood pressure regulation, breathing, and reproductive success. Therefore, serotonin release and serotonergic neuronal activity have to be precisely controlled and modulated by interacting brain circuits to adapt to specific emotional and environmental states. We will review the current knowledge about G protein-coupled receptors and ion channels involved in the regulation of serotonergic system, how their regulation is modulating the intrinsic activity of serotonergic neurons and its transmitter release and will discuss the latest methods for controlling the modulation of serotonin release and intracellular signaling in serotonergic neurons in vitro and in vivo.
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Affiliation(s)
- Takashi Maejima
- Department of Zoology and Neurobiology, Ruhr-University Bochum Bochum, Germany
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Ortega JE, Gonzalez-Lira V, Horrillo I, Herrera-Marschitz M, Callado LF, Meana JJ. Additive effect of rimonabant and citalopram on extracellular serotonin levels monitored with in vivo microdialysis in rat brain. Eur J Pharmacol 2013; 709:13-9. [PMID: 23562616 DOI: 10.1016/j.ejphar.2013.03.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 03/13/2013] [Accepted: 03/24/2013] [Indexed: 12/22/2022]
Abstract
Current pharmacological therapies for depression, including selective serotonin reuptake inhibitors (SSRI), are far from ideal. The cannabinoid system has been implicated in control of mood and neural processing of emotional information, and the modulation of serotonin (5-HT) release in the synaptic clefts. The aim of the present study was to evaluate whether the combination of a selective SSRI (citalopram) with a selective cannabinoid CB1 receptor antagonist (rimonabant) represents a more effective strategy than the antidepressant alone to enhance serotonergic transmission. For this purpose extracellular 5-HT levels were monitored with microdialysis in forebrain (prefrontal cortex, PFC) and mesencephalic (locus coeruleus, LC) serotonergic terminal areas in freely awake rats. Rimonabant at 10 mg/kg, i.p., but not at 3mg/kg i.p. increased 5-HT in both areas. Citalopram at 3, 5 and 10 mg/kg i.p. increased 5-HT both in PFC and LC in a dose-dependent manner. The effect of citalopram (5mg/kg, i.p.) on 5-HT levels was significantly enhanced by rimonabant at 10 mg/kg, i.p. but not at 3 mg/kg i.p. in both areas. The present results demonstrate that the cannabinoid CB1 receptor antagonist rimonabant is able to enhance in an additive manner the citalopram-induced increase of 5-HT concentrations in serotonergic terminal areas. The combination of a cannabinoid antagonist and a SSRI may provide a novel strategy to increase 5-HT availability, reducing the dose of SSRIs, and potentially decreasing the time lag for the clinical onset of the antidepressant effect.
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Affiliation(s)
- Jorge Emilio Ortega
- Department of Pharmacology, University of the Basque Country UPV/EHU, Spain.
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Iwasaki K, Takasaki K, Nogami A, Kubota K, Katsurabayashi S, Mishima K, Fujiwara M. [Pharmacological studies for the ameliorative effects of yokukansan on memory deficits and abnormal behavior in an animal model of dementia]. Nihon Yakurigaku Zasshi 2013; 140:66-70. [PMID: 22878569 DOI: 10.1254/fpj.140.66] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Tao R, Ma Z. Neural Circuit in the Dorsal Raphe Nucleus Responsible for Cannabinoid-Mediated Increases in 5-HT Efflux in the Nucleus Accumbens of the Rat Brain. ISRN PHARMACOLOGY 2012; 2012:276902. [PMID: 22830043 PMCID: PMC3399462 DOI: 10.5402/2012/276902] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 05/29/2012] [Indexed: 01/01/2023]
Abstract
In vivo microdialysis was used in this study to reveal the role of cannabinoids in regulating serotonin (5-HT) efflux in the nucleus accumbens (NAcc) and dorsal raphe nucleus (DRN). The cannabinoid CB1 receptor agonists WIN55212-2 and CP55940 systematically administered to rats caused significant increases in 5-HT efflux in the NAcc but failed to have an effect in the DRN. To reveal mechanisms underlying regionally selective responses, we tested the hypothesis that cannabinoids have both direct and indirect effects on 5-HT efflux, depending on the location of CB1 receptors in the neural circuit between DRN and NAcc. We showed that the direct effect of cannabinoids caused a reduction in 5-HT efflux whereas the indirect effect resulted in an increase. Furthermore, the indirect effect was blocked by the GABAA receptor antagonist bicuculline in the DRN, suggesting that the action is likely due to a presynaptic inhibition on GABAergic activity that exerts a tonic influence on neuronal circuits regulating 5-HT efflux. Involvement of GABAergic neurons was confirmed by measuring changes in GABA efflux. Taken together, our study suggests that cannabinoids may have direct and indirect effects on the 5-HT regulatory circuits, resulting in regionally selective changes of 5-HT efflux in the brain.
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Affiliation(s)
- Rui Tao
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA
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Bambico FR, Hattan PR, Garant JP, Gobbi G. Effect of delta-9-tetrahydrocannabinol on behavioral despair and on pre- and postsynaptic serotonergic transmission. Prog Neuropsychopharmacol Biol Psychiatry 2012; 38:88-96. [PMID: 22386778 DOI: 10.1016/j.pnpbp.2012.02.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 02/02/2012] [Accepted: 02/13/2012] [Indexed: 01/14/2023]
Abstract
Preclinical and clinical studies suggest that direct and indirect cannabinoid agonists, including enhancers of endocannabinoids, engender stress-relieving, anxiolytic and antidepressant effects, mediated by central CB(1) receptors (CB(1)Rs). The effect of the main pharmacologically active principle in cannabis, (-)-trans-Δ(9)-tetrahydrocannabinol (delta-9-THC), on depressive behavior and on the serotonin (5-HT) system, which is implicated in the mechanism of action of antidepressants, has not been extensively clarified. Here, we showed that repeated (5 days), but not single (acute) intraperitoneal (ip) treatment with delta-9-THC (1mg/kg) exerts antidepressant-like properties in the rat forced swim test (FST). This effect was CB(1)R-dependent because it was blocked by the CB(1)R antagonist rimonabant (1mg/kg, ip). Using in vivo electrophysiology, we demonstrated that delta-9-THC modulated dorsal raphe (DR) 5-HT neuronal activity through a CB(1)R-dependent mechanism. Acute intravenous delta-9-THC administration (0.1-1.5mg/kg) elicited a complex response profile, producing excitatory, inhibitory and inert responses of 5-HT neurons. Only excitatory responses were blocked by rimonabant. Finally, repeated but not single delta-9-THC administration (1mg/kg, ip) enhanced tonic 5-HT(1A) receptor activity in the hippocampus, a postsynaptic event commonly elicited by standard antidepressants. These results suggest that delta-9-THC, like other CB(1)R agonists and endocannabinoid enhancers, may possess antidepressant properties at low doses, and could modulate 5-HT transmission in the DR and hippocampus as standard antidepressants such as selective serotonin reuptake inhibitors.
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Esteban S, García-Sevilla JA. Effects induced by cannabinoids on monoaminergic systems in the brain and their implications for psychiatric disorders. Prog Neuropsychopharmacol Biol Psychiatry 2012; 38:78-87. [PMID: 22133541 DOI: 10.1016/j.pnpbp.2011.11.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 11/14/2011] [Accepted: 11/14/2011] [Indexed: 12/19/2022]
Abstract
The endocannabinoid system and CB(1) receptors participate in the control of emotional behavior and mood through a functional coupling with the classic monoaminergic systems. In general, the acute stimulation of CB(1) receptors increases the activity (spontaneous firing rate) of noradrenergic (NE), serotonergic (5-HT) and dopaminergic (DA) neurons as well as the synthesis and/or release of the corresponding neurotransmitter in specific brain regions. Notably, the antagonist/inverse agonist rimonabant (SR141617A) can decrease the basal activity of NE and 5-HT neurons, suggesting a tonic/constitutive regulation of these neuronal systems by endocannabinoids acting at CB(1) receptors. Monoaminergic systems are modulated via CB(1) receptors by direct or indirect effects depending on the localization of this inhibitory receptor, which can be present on monoaminergic neurons themselves and/or inhibitory (GABAergic) and/or excitatory (glutamatergic) regulatory neurons. The repeated stimulation of CB(1) receptors is not associated with the induction of tolerance (receptor desensitization) on the activity of NE, 5-HT and DA neurons, in contrast to chronic agonist effects on neurotransmitter synthesis and/or release in some brain regions. CB(1) receptor desensitization may alter the direct and/or indirect effects of cannabinoid drugs modulating the functionality of monoaminergic systems. The sustained activation of monoaminergic neurons by cannabinoid drugs can also be related to changes in the function of presynaptic inhibitory α(2)-adrenoceptors or 5-HT(1A) receptors (autoreceptors and heteroreceptors), whose sensitivity is downregulated or upregulated upon chronic CB(1) agonist exposure. The functional interactions between endocannabinoids and monoaminergic systems in the brain indicate a potential role for CB(1) receptor signaling in the neurobiology of various psychiatric disorders, including major depression and schizophrenia as the major syndromes.
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Affiliation(s)
- Susana Esteban
- Laboratorio de Neurofarmacología, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears (UIB), Palma de Mallorca, Spain.
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Dalton VS, Verdurand M, Walker A, Hodgson DM, Zavitsanou K. Synergistic Effect between Maternal Infection and Adolescent Cannabinoid Exposure on Serotonin 5HT1A Receptor Binding in the Hippocampus: Testing the "Two Hit" Hypothesis for the Development of Schizophrenia. ISRN PSYCHIATRY 2012; 2012:451865. [PMID: 23738203 PMCID: PMC3658855 DOI: 10.5402/2012/451865] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 04/10/2012] [Indexed: 12/19/2022]
Abstract
Infections during pregnancy and adolescent cannabis use have both been identified as environmental risk factors for schizophrenia. We combined these factors in an animal model and looked at their effects, alone and in combination, on serotonin 5HT1A receptor binding (5HT1AR) binding longitudinally from late adolescence to adulthood. Pregnant rats were exposed to the viral mimic poly I:C on embryonic day 15. Adolescent offspring received daily injections of the cannabinoid HU210 for 14 days starting on postnatal day (PND) 35. Hippocampal and cortical 5HT1AR binding was quantified autoradiographically using [3H]8-OH-DPAT, in late adolescent (PND 55), young adult (PND 65) and adult (PND 90) rats. Descendants of poly I:C treated rats showed significant increases of 15–18% in 5HT1AR in the hippocampus (CA1) compared to controls at all developmental ages. Offspring of poly I:C treated rats exposed to HU210 during adolescence exhibited even greater elevations in 5HT1AR (with increases of 44, 29, and 39% at PNDs 55, 65, and 90). No effect of HU210 alone was observed. Our results suggest a synergistic effect of prenatal infection and adolescent cannabinoid exposure on the integrity of the serotoninergic system in the hippocampus that may provide the neurochemical substrate for abnormal hippocampal-related functions relevant to schizophrenia.
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Affiliation(s)
- Victoria S Dalton
- Schizophrenia Research Institute, Sydney, NSW 2010, Australia ; Department of Psychiatry and Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
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Involvement of opioid system in cognitive deficits induced by ∆⁹-tetrahydrocannabinol in rats. Psychopharmacology (Berl) 2012; 219:1111-8. [PMID: 21858449 DOI: 10.1007/s00213-011-2442-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 08/02/2011] [Indexed: 02/02/2023]
Abstract
RATIONALE Cannabis is a widely used illicit substance. ∆(9)-Tetrahydrocannabinol (THC), the major psychoactive component of cannabis, is known to induce cognitive deficits that closely resemble the impairment observed in schizophrenic patients. We previously reported that THC (6 mg/kg) impairs spatial memory in the eight-arm radial maze, and that this memory disturbance was reversed by the cannabinoid CB(1) receptor antagonist rimonabant (0.1 mg/kg), suggesting that the effect of THC is mediated through cannabinoid CB(1) receptors. OBJECTIVES The present study was designed to examine the possible involvement of opioid receptors in the THC-induced impairment of spatial memory. METHODS The effects of treatment with the nonselective opioid receptor antagonist naloxone (0.3 and 1 mg/kg), the μ-opioid receptor antagonist β-funaltrexamine (0.3 and 1 mg/kg), the δ-opioid receptor antagonist naltrindole (1 and 3 mg/kg), and the κ-opioid receptor antagonist nor-binaltorphimine (0.03 and 0.1 mg/kg) on the impairment of spatial memory induced by THC were evaluated using the eight-arm radial maze. RESULTS The nonselective opioid receptor antagonist naloxone, the μ-opioid receptor antagonist β-funaltrexamine, and the κ-opioid receptor antagonist nor-binaltorphimine, but not the δ-opioid receptor antagonist naltrindole, attenuated THC-induced cognitive deficits, suggesting an involvement of μ- and κ-opioid receptors in this behavioral response. CONCLUSIONS These results demonstrate that the endogenous opioid system is involved in the regulation of the acute short-term and working memory deficits induced by cannabis.
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Cannabidiol inhibits the hyperphagia induced by cannabinoid-1 or serotonin-1A receptor agonists. Pharmacol Biochem Behav 2011; 98:268-72. [DOI: 10.1016/j.pbb.2011.01.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 12/01/2010] [Accepted: 01/08/2011] [Indexed: 11/24/2022]
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Modulation of the serotonin system by endocannabinoid signaling. Neuropharmacology 2011; 61:414-20. [PMID: 21354188 DOI: 10.1016/j.neuropharm.2011.02.016] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 02/14/2011] [Accepted: 02/15/2011] [Indexed: 12/31/2022]
Abstract
The cannabinoid CB(1) receptors and their endogenous agonists, endocannabinoids (eCBs), are ubiquitously distributed throughout the central nervous system (CNS), where they play a key role in the regulation of neuronal excitability. As such, CB signaling has been implicated in the regulation of a myriad of physiological functions ranging from feeding homoeostasis to emotional and motivational processes. Ample evidence from behavioral studies also suggests that eCBs are important regulators of stress responses and a deficit in eCB signaling contributes to stress-related disorders such as anxiety and depression. The eCB-induced modulation of stress-related behaviors appears to be mediated, at least in part, through the regulation of the serotoninergic system. In this article, we review the role of eCB signaling in the regulation of the serotoninergic system with special emphasis on the cellular mechanisms by which cannabinoid CB(1) receptors modulate the excitability of dorsal raphe serotonin neurons.
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Cannabinoid administration increases 5HT1A receptor binding and mRNA expression in the hippocampus of adult but not adolescent rats. Neuroscience 2010; 169:315-24. [DOI: 10.1016/j.neuroscience.2010.04.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Revised: 02/26/2010] [Accepted: 04/03/2010] [Indexed: 11/18/2022]
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Mendiguren A, Pineda J. Effect of the CB(1) receptor antagonists rimonabant and AM251 on the firing rate of dorsal raphe nucleus neurons in rat brain slices. Br J Pharmacol 2009; 158:1579-87. [PMID: 19845674 DOI: 10.1111/j.1476-5381.2009.00434.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Previous studies have suggested a regulation of 5-hydroxytryptamine (5-HT) neurons by the endocannabinoid system. The aim of our work was to examine the effect of two CB(1) receptor antagonists, SR141716A (rimonabant, Sanofi-Synthélabo Recherche, Montpellier, France) and N-(piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (AM251, Tocris Cookson, Bristol, UK), on the firing rate of dorsal raphe nucleus (DRN) neurons. EXPERIMENTAL APPROACH Single-unit extracellular recordings were performed to study the effect of CB(1) receptor antagonists in slices of the DRN from rat brain. KEY RESULTS Rimonabant (1 microM) and AM251 (1 microM) decreased the firing rate of about 50% of all the recorded DRN 5-HT cells. The GABA(A)receptor antagonist picrotoxin (20 microM) (Sigma) prevented and also reversed the inhibitory effect of rimonabant (1 microM) and AM251 (1 microM), suggesting that CB(1) receptors regulate 5-HT neurons through the GABAergic system. However, the CB(1)/CB(2) receptor agonist R-(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)-methyl]pyrrolol[1,2,3-de]-1,4-benzoxazinyl]-(1-naphthalenyl) methanone mesylate salt (10 microM) (WIN55212-2, Sigma, St. Louis, MO, USA) failed to change the firing activity of non-5-HT (presumably GABAergic) neurons in the DRN. The endocannabinoid N-(2-hydroxyethyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (anandamide, Tocris Cookson) (10 microM) also inhibited the firing activity of a number of 5-HT neurons, but this inhibition was not blocked by rimonabant (1 microM) or AM251 (1 microM), and the stable analogue R-(+) N-(2-hydroxy-1methylethyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (methanandamide, Tocris Cookson) (10 microM) did not mimic this effect. The selective CB(1) receptor agonist arachidonoyl-2-chloroethylamide (ACEA) (1 microM) only slightly increased the firing rate of DRN 5-HT cells. CONCLUSIONS AND IMPLICATIONS These results suggest a tonic/constitutive regulation of DRN 5-HT neurons by the endocannabinoid system, which may occur through a CB(1) receptor-mediated inhibition of the GABAergic system. The inhibitory effect of anandamide may be mediated through a CB(1) receptor-independent mechanism.
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Affiliation(s)
- Aitziber Mendiguren
- Department of Pharmacology, University of the Basque Country, Leioa, Bizkaia, Spain
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Effects of cannabinoids infused into the dorsal hippocampus upon memory formation in 3-days apomorphine-treated rats. Neurobiol Learn Mem 2009; 92:391-9. [DOI: 10.1016/j.nlm.2009.05.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Revised: 05/10/2009] [Accepted: 05/13/2009] [Indexed: 11/19/2022]
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Influence of intracerebroventricular or intraperitoneal administration of cannabinoid receptor agonist (WIN 55,212-2) and inverse agonist (AM 251) on the regulation of food intake and hypothalamic serotonin levels. Br J Nutr 2009; 101:1569-78. [PMID: 19245736 DOI: 10.1017/s0007114508083530] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The effect of intracerebroventricular or intraperitoneal administration of cannabinoid receptor agonist WIN 55,212-2 or inverse agonist AM 251 on food intake and extracellular levels of serotonin and acetic acid 5-hydroxy-indol from presatiated rats was studied. Compared to the vehicle-injected control, the intracerebroventricular administration of WIN 55,212-2 was associated with a significant increase in food intake, whereas the administration of AM 251 caused a significant reduction in this respect. These results were accompanied by considerable reductions or increases in serotonin and acetic acid 5-hydroxy-indol levels compared to the vehicle-injected control and the baseline values for the different experimental groups studied. Intraperitoneal administration of WIN 55,212-2 at doses of 1 and 2 mg/kg promoted hyperphagia up to 6 h after injection, whereas administration of a higher dose (5 mg/kg) significantly inhibited food intake and motor behaviour in partially satiated rats. Administration of any of the AM 251 doses studied (0.5, 1, 2, 5 mg/kg) led to a significant decrease in the amount of food ingested from 2 h after the injection, compared to the vehicle-injected control group, with the most striking effect being observed when the 5 mg/kg dose was injected.
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Moranta D, Esteban S, García-Sevilla JA. Chronic treatment and withdrawal of the cannabinoid agonist WIN 55,212-2 modulate the sensitivity of presynaptic receptors involved in the regulation of monoamine syntheses in rat brain. Naunyn Schmiedebergs Arch Pharmacol 2008; 379:61-72. [PMID: 18709357 DOI: 10.1007/s00210-008-0337-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Accepted: 07/07/2008] [Indexed: 10/21/2022]
Abstract
Brain monoamines are involved in many neurochemical and behavioral effects of cannabinoids, but little is known on the regulation of noradrenaline, dopamine, and serotonin (5-HT) synthesis in cannabinoid addiction. This study investigated in rat brain the chronic effects of the potent cannabinoid agonist WIN 55,212-2 and of rimonabant-precipitated withdrawal, as well as the sensitivity of synthesis-modulating inhibitory receptors, on the accumulation of L-3,4-dihydroxyphenylalanine (DOPA) and 5-HTP after decarboxylase inhibition. Acute WIN (8 mg/kg; 1 h) increased DOPA synthesis in cortex (52%), hippocampus (51%), and cerebellum (56%) and decreased DOPA accumulation in striatum (31%). Acute WIN also decreased the synthesis of 5-HTP in all brain regions (40-53%). Chronic WIN (2-8 mg/kg; 5 days) and/or antagonist-precipitated withdrawal induced tolerance to the acute effects of WIN on the accumulation of DOPA (cortex and striatum) and 5-HTP (all brain regions). The inhibitory effect of clonidine (alpha2-agonist; 1 mg/kg) on the accumulation of DOPA (15-41%) and 5-HTP (22-41%) was markedly decreased or abolished after chronic WIN and precipitated withdrawal, mainly in noradrenergic and serotonergic brain regions, which indicated desensitization of alpha2-autoreceptors and alpha2-heteroreceptors regulating the synthesis of noradrenaline and 5-HT. In WIN-dependent rats (chronic and withdrawal states), the effect of a low dose of (+/-)-8-hydroxy-2-(di-n-propylamino)-tetralin (5-HT1A agonist; 0.1 mg/kg) on the accumulation of precursor amino acids was markedly potentiated in cerebellum and striatum, indicating the induction of supersensitivity of 5-HT1A-autoreceptors and 5-HT1A-heteroreceptors that regulate the synthesis of 5-HT, noradrenaline, and dopamine in these brain regions. These chronic adaptations in presynaptic receptor function could play a relevant role in cannabinoid addiction.
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Affiliation(s)
- David Moranta
- Laboratori de Neurofarmacologia, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Cra. Valldemossa km 7.5, 07122, Palma de Mallorca, Spain
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López-Moreno JA, González-Cuevas G, Moreno G, Navarro M. The pharmacology of the endocannabinoid system: functional and structural interactions with other neurotransmitter systems and their repercussions in behavioral addiction. Addict Biol 2008; 13:160-87. [PMID: 18422831 DOI: 10.1111/j.1369-1600.2008.00105.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Addiction is a chronic, recurring and complex disorder. It is characterized by anomalous behaviors that are linked to permanent or long-lasting neurobiological alterations. Furthermore, the endocannabinoid system has a crucial role in mediating neurotransmitter release as one of the main neuromodulators of the mammalian central nervous system. The purpose of the present review is to instruct readers about the functional and structural interactions between the endocannabinoid system and the main neurotransmitter systems of the central nervous system in the context of drug addiction. With this aim, we have systematically reviewed the main findings of most of the existing literature that explores cross-talk in the five brain areas that are most traditionally implicated in addiction: amygdala, prefrontal cortex, nucleus accumbens, hippocampus and ventral tegmental area (VTA). The neurotransmission systems influenced by the pharmacology of the endocannabinoid system in these brain areas, which are reviewed here, are gamma-aminobutyric acid (GABA), glutamate, the main biogenic amines (dopamine, noradrenaline and serotonin), acetylcholine and opioids. We show that all of these neurotransmitter systems can be modulated differentially in each brain area by the activation or deactivation of cannabinoid CB1 brain receptors. Specifically, most of the studies relate to the hippocampus and nucleus accumbens. Moreover, the neurotransmitter with the fewest number of related studies is acetylcholine (excepting in the hippocampus), whereas there is a large number that evaluates GABA, glutamate and dopamine. Finally, we propose a possible interpretation of the role of the endocannabinoid system in the phenomenon of addiction.
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Affiliation(s)
- José Antonio López-Moreno
- Department of Psychobiology, Faculty of Psychology, Campus de Somosaguas, Complutense University of Madrid, Spain.
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Delta(9)-tetrahydrocannabinol prolongs the immobility time in the mouse forced swim test: involvement of cannabinoid CB(1) receptor and serotonergic system. Eur J Pharmacol 2008; 589:117-21. [PMID: 18565508 DOI: 10.1016/j.ejphar.2008.03.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2007] [Revised: 03/07/2008] [Accepted: 03/27/2008] [Indexed: 11/20/2022]
Abstract
In the present study, we investigated the effect of Delta(9)-tetrahydrocannabinol (THC), the principal psychoactive component of marijuana, on immobility time during the forced swim test. THC (2 and 6 mg/kg, i.p.) significantly prolonged the immobility time. In addition, THC at the same doses did not significantly affect locomotor activity in the open-field test. The selective cannabinoid CB(1) receptor antagonist rimonabant (3 mg/kg, i.p.) significantly reduced the enhancement of immobility by THC (6 mg/kg). Similarly, the selective serotonin (5-HT) reuptake inhibitor (SSRI) citalopram (10 mg/kg, i.p.) and 5-HT(1A/7) receptor agonist 8-hydroxy-2-(di-n-propylamino) tetralin (8-OH-DPAT, 0.3 mg/kg, i.p.) significantly reduced this THC-induced effect. Moreover, the selective 5-HT(1A) receptor antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) cyclohexane carboxamide dihydrochloride (WAY100635, 1 mg/kg, i.p.) and the postsynaptic 5-HT(1A) receptor antagonist MM-77 (0.1 mg/kg, i.p.) reversed this reduction effect of 8-OH-DPAT (0.3 mg/kg). In contrast, the selective 5-HT(7) receptor antagonist (R)-3-[2-[2-(4-methylpiperidin-1-yl)ethyl]pyrrolidine-1-sulfonyl]phenol hydrochloride (SB269970) had no effect on this reduction effect of 8-OH-DPAT. WAY100635 (1 mg/kg) also reversed the reduction effect of citalopram (10 mg/kg). These findings suggest that the 5-HT(1A) receptors are involved in THC-induced enhancement of immobility.
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Delta9-Tetrahydrocannabinol-induced cognitive deficits are reversed by olanzapine but not haloperidol in rats. Prog Neuropsychopharmacol Biol Psychiatry 2008; 32:499-506. [PMID: 18029074 DOI: 10.1016/j.pnpbp.2007.10.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 10/01/2007] [Accepted: 10/01/2007] [Indexed: 11/24/2022]
Abstract
Cannabis is the most widely used illicit substance. Delta9-Tetrahydrocannabinol (THC), the major psychoactive component of cannabis, is known to induce cognitive impairment that closely resembles the impairment observed in schizophrenic patients. THC has also been known to impair spatial memory in rats tested in the eight-arm radial maze. We previously reported that microinjection of THC (20 microg/side) into the rat dorsal hippocampus impaired spatial memory and that i.p. injection of THC (6 mg/kg) decreased the extracellular levels of acetylcholine (ACh) in the dorsal hippocampus. In the present study, we compared the effects of olanzapine, an atypical antipsychotic, with those of haloperidol, a typical neuroleptic, on the impairments of spatial memory and decreased ACh levels induced by THC (6 mg/kg, i.p.) in rats. We found that olanzapine (0.1 mg/kg, i.p.) reversed the THC-induced memory deficits and decrease in extracellular ACh levels, whereas haloperidol (0.03-0.3 mg, i.p.) had no effect. These results suggest that olanzapine may improve the THC-induced impairment of spatial memory, partly by enhancing ACh release in the dorsal hippocampus. Therefore, olanzapine could attenuate the acute short-term and working memory deficits induced by cannabis.
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Sano K, Mishima K, Koushi E, Orito K, Egashira N, Irie K, Takasaki K, Katsurabayashi S, Iwasaki K, Uchida N, Egawa T, Kitamura Y, Nishimura R, Fujiwara M. Delta 9-tetrahydrocannabinol-induced catalepsy-like immobilization is mediated by decreased 5-HT neurotransmission in the nucleus accumbens due to the action of glutamate-containing neurons. Neuroscience 2007; 151:320-8. [PMID: 18083311 DOI: 10.1016/j.neuroscience.2007.10.026] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Revised: 10/26/2007] [Accepted: 11/01/2007] [Indexed: 11/30/2022]
Abstract
Delta(9)-tetrahydrocannabinol (THC) has been reported to induce catalepsy-like immobilization, but the mechanism underlying this effect remains unclear. In the present study, in order to fully understand the neural circuits involved, we determined the brain sites involved in the immobilization effect in rats. THC dose-dependently induced catalepsy-like immobilization. THC-induced catalepsy-like immobilization is mechanistically different from that induced by haloperidol (HPD), because unlike HPD-induced catalepsy, animals with THC-induced catalepsy became normal again following sound and air-puff stimuli. THC-induced catalepsy was reversed by SR141716, a selective cannabinoid CB(1) receptor antagonist. Moreover, THC-induced catalepsy was abolished by lesions in the nucleus accumbens (NAc) and central amygdala (ACE) regions. On the other hand, HPD-induced catalepsy was suppressed by lesions in the caudate putamen (CP), substantia nigra (SN), globus pallidus (GP), ACE and lateral hypothalamus (LH) regions. Bilateral microinjection of THC into the NAc region induced catalepsy-like immobilization. This THC-induced catalepsy was inhibited by serotonergic drugs such as 5-hydroxy-L-tryptophan (5-HTP), a 5-HT precursor, and 5-methoxy-N,N-dimethyltryptamine (5-MeODMT), a 5-HT receptor agonist, as well as by anti-glutamatergic drugs such as MK-801 and amantadine, an N-methyl-d-aspartate (NMDA) receptor antagonist. THC significantly decreased 5-HT and glutamate release in the NAc, as shown by in vivo microdialysis. SR141716 reversed and MK-801 inhibited this decrease in 5-HT and glutamate release. These findings suggest that the THC-induced catalepsy is mechanistically different from HPD-induced catalepsy and that the catalepsy-like immobilization induced by THC is mediated by decreased 5-HT neurotransmission in the nucleus accumbens due to the action of glutamate-containing neurons.
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Affiliation(s)
- K Sano
- Department of Neuropharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Nanakuma 8-19-1, Fukuoka City, Fukuoka 814-0180, Japan
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Mato S, Aso E, Castro E, Martín M, Valverde O, Maldonado R, Pazos A. CB1 knockout mice display impaired functionality of 5-HT1A and 5-HT2A/C receptors. J Neurochem 2007; 103:2111-20. [PMID: 17944876 DOI: 10.1111/j.1471-4159.2007.04961.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Interaction between brain endocannabinoid (EC) and serotonin (5-HT) systems was investigated by examining 5-HT-dependent behavioral and biochemical responses in CB(1) receptor knockout mice. CB(1) knockout animals exhibited a significant reduction in the induction of head twitches and paw tremor by the 5-HT(2A/C) receptor selective agonist (+/-) DOI, as well as a reduced hypothermic response following administration of the 5-HT(1A) receptor agonist (+/-)-8-OH-DPAT. Additionally, exposure to the tail suspension test induced enhanced despair responses in CB(1) knockout mice. However, the tricyclic antidepressant imipramine and the 5-HT selective reuptake inhibitor fluoxetine induced similar decreases in the time of immobility in the tail suspension test in CB(1) receptor knockout and wild-type mice. No differences were found between both genotypes with regard to 5-HT(2A) receptor and 5-HT(1A) receptors levels, measured by autoradiography in different brain areas. However, a significant decrease in the ability of both, the 5-HT(1A) receptor agonist (+/-)-8-OH-DPAT and the 5-HT(2A/C) receptor agonist (-)DOI, to stimulate [(35)S]GTPgammaS binding was detected in the hippocampal CA(1) area and fronto-parietal cortex of CB(1) receptor knockout mice, respectively. This study provides evidence that CB(1) receptors are involved in the regulation of serotonergic responses mediated by 5-HT(2A/C) and 5-HT(1A) receptors, and suggests that a reduced coupling of 5-HT(1A) and 5-HT(2A) receptors to G proteins might be involved in these effects.
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Affiliation(s)
- Susana Mato
- Department of Physiology and Pharmacology, University of Cantabria, Cantabria, Spain
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