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LoParco CR, Tillett KK, Chen-Sankey J, Berg CJ, Rossheim ME. Public health considerations about tetrahydrocannabinol-infused beverages. Addiction 2024. [PMID: 39327681 DOI: 10.1111/add.16676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2024] [Accepted: 09/04/2024] [Indexed: 09/28/2024]
Affiliation(s)
- Cassidy R LoParco
- Milken Institute School of Public Health, George Washington University, Washington, DC, USA
| | - Kayla K Tillett
- School of Public Health, University of North Texas Health Science Center, Fort Worth, TX, USA
| | | | - Carla J Berg
- Milken Institute School of Public Health, George Washington University, Washington, DC, USA
- George Washington Cancer Center, George Washington University, Washington, DC, USA
| | - Matthew E Rossheim
- School of Public Health, University of North Texas Health Science Center, Fort Worth, TX, USA
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2
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Winstone J, Shafique H, Clemmer ME, Mackie K, Wager-Miller J. Effects of Tetrahydrocannabinol and Cannabidiol on Brain-Derived Neurotrophic Factor and Tropomyosin Receptor Kinase B Expression in the Adolescent Hippocampus. Cannabis Cannabinoid Res 2023; 8:612-622. [PMID: 35639364 PMCID: PMC10442678 DOI: 10.1089/can.2021.0025] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Introduction: Adolescence is an important phase in brain maturation, specifically it is a time during which weak synapses are pruned and neural pathways are strengthened. Adolescence is also a time of experimentation with drugs, including cannabis, which may have detrimental effects on the developing nervous system. The cannabinoid type 1 receptor (CB1) is an important modulator of neurotransmitter release and plays a central role in neural development. Neurotrophic factors such as brain-derived neurotrophic factor (BDNF) and its receptor, tropomyosin receptor kinase B (TrkB), are also critical during development for axon guidance and synapse specification. Objective: The objective of this study was to examine the effects of the phytocannabinoids, Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), on the expression of BDNF, its receptor TrkB, and other synaptic markers in the adolescent mouse hippocampus. Materials and Methods: Mice of both sexes were injected daily from P28 to P49 with 3 mg/kg THC, CBD, or a combination of THC/CBD. Brains were harvested on P50, and the dorsal and ventral hippocampi were analyzed for levels of BDNF, TrkB, and several synaptic markers using quantitative polymerase chain reaction, western blotting, and image analyses. Results: THC treatment statistically significantly reduced transcript levels of BDNF in adolescent female (BDNF I) and male (BDNF I, II, IV, VI, and IX) hippocampi. These changes were prevented when CBD was co-administered with THC. CBD by itself statistically significantly increased expression of some transcripts (BDNF II, VI, and IX for females, BDNF VI for males). No statistically significant changes were observed in protein expression for BDNF, TrkB, phospho-TrkB, phospho-CREB (cAMP response element-binding protein), and the synaptic markers, vesicular GABA transporter, vesicular glutamate transporter, synaptobrevin, and postsynaptic density protein 95. However, CB1 receptors were statistically significantly reduced in the ventral hippocampus with THC treatment. Conclusions: This study found changes in BDNF mRNA expression within the hippocampus of adolescent mice exposed to THC and CBD. THC represses transcript expression for some BDNF variants, and this effect is rescued when CBD is co-administered. These effects were seen in both males and females, but sex differences were observed in specific BDNF isoforms. While a statistically significant reduction in CB1 receptor protein in the ventral dentate gyrus was seen, no other changes in protein levels were observed.
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Affiliation(s)
- Joanna Winstone
- Department of Psychological and Brain Sciences, The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, USA
| | - Hana Shafique
- Department of Psychological and Brain Sciences, The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, USA
| | - Madeleine E. Clemmer
- Department of Psychological and Brain Sciences, The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, USA
| | - Ken Mackie
- Department of Psychological and Brain Sciences, The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, USA
| | - Jim Wager-Miller
- Department of Psychological and Brain Sciences, The Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana, USA
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3
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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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4
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Sorkhou M, Bedder RH, George TP. The Behavioral Sequelae of Cannabis Use in Healthy People: A Systematic Review. Front Psychiatry 2021; 12:630247. [PMID: 33664685 PMCID: PMC7920961 DOI: 10.3389/fpsyt.2021.630247] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 01/25/2021] [Indexed: 12/13/2022] Open
Abstract
Background: Cannabis is known to have a broad range of effects on behavior, including experiencing a "high" and tranquility/relaxation. However, there are several adverse behavioral sequalae that can arise from cannabis use, depending on frequency of use, potency (e.g., THC content), age of onset, and cumulative exposure. This systematic review examined evidence for cannabis-related adverse behavioral sequalae in otherwise healthy human subjects. Methods: Following PRISMA guidelines, we conducted a systematic review of cross-sectional and longitudinal studies from 1990 to 2020 that identified cannabis-related adverse behavioral outcomes in subjects without psychiatric and medical co-morbidities from PubMed and PsychInfo searches. Key search terms included "cannabis" OR "tetrahydrocannabinol" OR "cannabidiol" OR "marijuana" AND "anxiety" OR "depression" OR "psychosis" OR "schizophrenia" "OR "IQ" OR "memory" OR "attention" OR "impulsivity" OR "cognition" OR "education" OR "occupation". Results: Our search detected a total of 2,870 studies, from which we extracted 124 relevant studies from the literature on cannabis effects in the non-clinical population. Effects of cannabis on several behavioral sequelae including cognition, motivation, impulsivity, mood, anxiety, psychosis intelligence, and psychosocial functioning were identified. The preponderance of the evidence suggests that frequency of cannabis use, THC (but not CBD) content, age of onset, and cumulative cannabis exposure can all contribute to these adverse outcomes in individuals without a pre-existing medical condition or psychiatric disorder. The strongest evidence for the negative effects of cannabis are for psychosis and psychosocial functioning. Conclusions: Although more research is needed to determine risk factors for development of adverse behavioral sequelae of cannabis use, these findings underline the importance of understanding vulnerability to the adverse effects of cannabis, which has implications for prevention and treatment of problematic cannabis use.
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Affiliation(s)
- Maryam Sorkhou
- Addictions Division, Centre for Addiction and Mental Health (CAMH), University of Toronto, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Rachel H Bedder
- Department of Psychology, Ryerson University, Toronto, ON, Canada
| | - Tony P George
- Addictions Division, Centre for Addiction and Mental Health (CAMH), University of Toronto, Toronto, ON, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada.,Department of Psychiatry, University of Toronto, Toronto, ON, Canada
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5
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Prini P, Zamberletti E, Manenti C, Gabaglio M, Parolaro D, Rubino T. Neurobiological mechanisms underlying cannabis-induced memory impairment. Eur Neuropsychopharmacol 2020; 36:181-190. [PMID: 32139186 DOI: 10.1016/j.euroneuro.2020.02.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 01/27/2020] [Accepted: 02/17/2020] [Indexed: 01/23/2023]
Abstract
A growing body of literature suggests that cannabis intake can induce memory loss in humans and animals. Besides the recreational use, daily cannabis users may also belong to the ever-increasing population of patients who are administered cannabis as a medicine. As such, they also can experience impairments in memory as a negative side effect of their therapy. Comprehension of the neurobiological mechanisms responsible for such detrimental effects would be therefore of paramount relevance to public health. The investigation of neurobiological mechanisms in humans, despite the progress in the development of imaging technologies that allow the study of brain structure and function, still suffers substantial limitations. Animal models, instead, enable us to establish a causal relationship and thus to better elucidate the neurobiological mechanisms underlying the process under study. In this review, we will attempt to collect the insight coming from animal models about cannabis effects on memory, trying to depict a picture of the neurobiological mechanisms contributing to the development of cognitive deficits following cannabis use.
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Affiliation(s)
- Pamela Prini
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio VA, Italy
| | - Erica Zamberletti
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio VA, Italy
| | - Cristina Manenti
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio VA, Italy
| | - Marina Gabaglio
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio VA, Italy
| | - Daniela Parolaro
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio VA, Italy; Zardi-Gori Foundation, Milan, Italy
| | - Tiziana Rubino
- Department of Biotechnology and Life Sciences, and Neuroscience Center, University of Insubria, Busto Arsizio VA, Italy.
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6
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Chen HT, Mackie K. Adolescent Δ 9-Tetrahydrocannabinol Exposure Selectively Impairs Working Memory but Not Several Other mPFC-Mediated Behaviors. Front Psychiatry 2020; 11:576214. [PMID: 33262712 PMCID: PMC7688511 DOI: 10.3389/fpsyt.2020.576214] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/23/2020] [Indexed: 12/19/2022] Open
Abstract
As the frequency of cannabis use by 14-16-year-olds increases, it becomes increasingly important to understand the effect of cannabis on the developing central nervous system. Using mice as a model system, we treated adolescent (28 day old) C57BL6/J mice of both sexes for 3 weeks with 3 mg/kg tetrahydrocannabinol (THC). Starting a week after the last treatment, several cognitive behaviors were analyzed. Mice treated with THC as adolescents acquired proficiency in a working memory task more slowly than vehicle-treated mice. Working memory recall in both sexes of THC-treated mice was also deficient during increasing cognitive load compared to vehicle-treated mice. Our adolescent THC treatment did not strongly affect social preference, anxiety behaviors, or decision-making behaviors on the elevated T maze task. In summary, under the conditions of this study, adolescent THC treatment of mice markedly affected the establishment, and persistence of working memory, while having little effect on decision-making, social preference or anxiety behaviors. This study provides further support that adolescent THC affects specific behavioral domains.
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Affiliation(s)
- Han-Ting Chen
- Department of Psychology and Brain Sciences, Indiana University, Bloomington, IN, United States.,Gill Center, Indiana University, Bloomington, IN, United States
| | - Ken Mackie
- Department of Psychology and Brain Sciences, Indiana University, Bloomington, IN, United States.,Gill Center, Indiana University, Bloomington, IN, United States
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Leffa DT, Ferreira SG, Machado NJ, Souza CM, Rosa FD, de Carvalho C, Kincheski GC, Takahashi RN, Porciúncula LO, Souza DO, Cunha RA, Pandolfo P. Caffeine and cannabinoid receptors modulate impulsive behavior in an animal model of attentional deficit and hyperactivity disorder. Eur J Neurosci 2019; 49:1673-1683. [PMID: 30667546 DOI: 10.1111/ejn.14348] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 12/15/2018] [Accepted: 12/27/2018] [Indexed: 12/12/2022]
Abstract
Attention deficit and hyperactivity disorder (ADHD) is characterized by impaired levels of hyperactivity, impulsivity, and inattention. Adenosine and endocannabinoid systems tightly interact in the modulation of dopamine signaling, involved in the neurobiology of ADHD. In this study, we evaluated the modulating effects of the cannabinoid and adenosine systems in a tolerance to delay of reward task using the most widely used animal model of ADHD. Spontaneous Hypertensive Rats (SHR) and Wistar-Kyoto rats were treated chronically or acutely with caffeine, a non-selective adenosine receptor antagonist, or acutely with a cannabinoid agonist (WIN55212-2, WIN) or antagonist (AM251). Subsequently, animals were tested in the tolerance to delay of reward task, in which they had to choose between a small, but immediate, or a large, but delayed, reward. Treatment with WIN decreased, whereas treatment with AM251 increased the choices of the large reward, selectively in SHR rats, indicating a CB1 receptor-mediated increase in impulsive behavior. An acute pre-treatment with caffeine blocked WIN effects. Conversely, a chronic treatment with caffeine increased the impulsive phenotype and potentiated the WIN effects. The results indicate that both cannabinoid and adenosine receptors modulate impulsive behavior in SHR: the antagonism of cannabinoid receptors might be effective in reducing impulsive symptoms present in ADHD; in addition, caffeine showed the opposite effects on impulsive behavior depending on the length of treatment. These observations are of particular importance to consider when therapeutic manipulation of CB1 receptors is applied to ADHD patients who consume coffee.
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Affiliation(s)
- Douglas T Leffa
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Samira G Ferreira
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Nuno J Machado
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Carolina M Souza
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Fernanda da Rosa
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Cristiane de Carvalho
- Department of Pharmacology, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Grasielle C Kincheski
- Institute of Medical Biochemistry Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Reinaldo N Takahashi
- Department of Pharmacology, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Lisiane O Porciúncula
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Diogo O Souza
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Pablo Pandolfo
- Department of Neurobiology, Universidade Federal Fluminense, Niterói, Brazil
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8
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Mouro FM, Batalha VL, Ferreira DG, Coelho JE, Baqi Y, Müller CE, Lopes LV, Ribeiro JA, Sebastião AM. Chronic and acute adenosine A 2A receptor blockade prevents long-term episodic memory disruption caused by acute cannabinoid CB 1 receptor activation. Neuropharmacology 2017; 117:316-327. [PMID: 28235548 DOI: 10.1016/j.neuropharm.2017.02.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 01/17/2017] [Accepted: 02/19/2017] [Indexed: 11/19/2022]
Abstract
Cannabinoid-mediated memory impairment is a concern in cannabinoid-based therapies. Caffeine exacerbates cannabinoid CB1 receptor (CB1R)-induced memory deficits through an adenosine A1 receptor-mediated mechanism. We now evaluated how chronic or acute blockade of adenosine A2A receptors (A2ARs) affects long-term episodic memory deficits induced by a single injection of a selective CB1R agonist. Long-term episodic memory was assessed by the novel object recognition (NOR) test. Mice received an intraperitoneal (i.p.) injection of the CB1/CB2 receptor agonist WIN 55,212-2 (1 mg/kg) immediately after the NOR training, being tested for novelty recognition 24 h later. Anxiety levels were assessed by the Elevated Plus Maze test, immediately after the NOR. Mice were also tested for exploratory behaviour at the Open Field. For chronic A2AR blockade, KW-6002 (istradefylline) (3 mg/kg/day) was administered orally for 30 days; acute blockade of A2ARs was assessed by i.p. injection of SCH 58261 (1 mg/kg) administered either together with WIN 55,212-2 or only 30 min before the NOR test phase. The involvement of CB1Rs was assessed by using the CB1R antagonist, AM251 (3 mg/kg, i.p.). WIN 55,212-2 caused a disruption in NOR, an action absent in mice also receiving AM251, KW-6002 or SCH 58261 during the encoding/consolidation phase; SCH 58251 was ineffective if present during retrieval only. No effects were detected in the Elevated Plus maze or Open Field Test. The finding that CB1R-mediated memory disruption is prevented by antagonism of adenosine A2ARs, highlights a possibility to prevent cognitive side effects when therapeutic application of CB1R drugs is desired.
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MESH Headings
- Adenosine A2 Receptor Antagonists/administration & dosage
- Animals
- Benzoxazines/pharmacology
- Calcium Channel Blockers/pharmacology
- Cannabinoid Receptor Agonists/toxicity
- Exploratory Behavior/drug effects
- Exploratory Behavior/physiology
- Male
- Maze Learning/drug effects
- Maze Learning/physiology
- Memory Disorders/chemically induced
- Memory Disorders/metabolism
- Memory Disorders/prevention & control
- Memory, Episodic
- Memory, Long-Term/drug effects
- Memory, Long-Term/physiology
- Mice, Inbred C57BL
- Morpholines/pharmacology
- Naphthalenes/pharmacology
- Piperidines/pharmacology
- Purines/administration & dosage
- Pyrazoles/pharmacology
- Pyrimidines/administration & dosage
- Receptor, Adenosine A2A/metabolism
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/metabolism
- Recognition, Psychology/drug effects
- Recognition, Psychology/physiology
- Triazoles/administration & dosage
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Affiliation(s)
- Francisco M Mouro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Vânia L Batalha
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Diana G Ferreira
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Joana E Coelho
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Younis Baqi
- Pharma-Zentrum Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie I, University of Bonn, Germany; Department of Chemistry, Faculty of Science, Sultan Qaboos University, Muscat, Oman
| | - Christa E Müller
- Pharma-Zentrum Bonn, Pharmazeutisches Institut, Pharmazeutische Chemie I, University of Bonn, Germany
| | - Luísa V Lopes
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Joaquim A Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Ana M Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal.
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9
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Psychopathology Related to Energy Drinks: A Psychosis Case Report. Case Rep Psychiatry 2017; 2017:5094608. [PMID: 28116203 PMCID: PMC5237741 DOI: 10.1155/2017/5094608] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 12/18/2016] [Indexed: 01/22/2023] Open
Abstract
Energy drinks (ED) are nonalcoholic beverages that have caffeine as their most common active substance. The rapid expansion of ED consumption has created concern in the scientific community as well as in the public opinion. We report a psychotic episode probably triggered by ED abuse in a young adult without previous psychotic disorders. We have reviewed the literature regarding the relationship between caffeine, energy drinks, and psychopathology. Few articles have been published about mental health effects of energy drinks and caffeine abuse. Nevertheless, this relationship has been suggested, specifically with anxiety disorders, manic episodes, suicide attempts, psychotic decompensation, and substance use disorder. ED consumption could represent a global public health problem because of the potential severe adverse effects in mental and physical health. To our knowledge, this article is probably the first case of psychosis related to ED abuse in an individual without previous psychotic disorders.
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Rombo DM, Ribeiro JA, Sebastião AM. Hippocampal GABAergic transmission: a new target for adenosine control of excitability. J Neurochem 2016; 139:1056-1070. [PMID: 27778347 DOI: 10.1111/jnc.13872] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 09/30/2016] [Accepted: 10/21/2016] [Indexed: 01/01/2023]
Abstract
Physiological network functioning in the hippocampus is dependent on a balance between glutamatergic cell excitability and the activity of diverse local circuit neurons that release the inhibitory neurotransmitter γ-aminobutyric acid (GABA). Tuners of neuronal communication such as adenosine, an endogenous modulator of synapses, control hippocampal network operations by regulating excitability. Evidence has been recently accumulating on the influence of adenosine on different aspects of GABAergic transmission to shape hippocampal function. This review addresses how adenosine, through its high-affinity A1 (A1 R) and A2A receptors (A2A R), interferes with different GABA-mediated forms of inhibition in the hippocampus to regulate neuronal excitability. Adenosine-mediated modulation of phasic/tonic inhibitory transmission, of GABA transport mechanisms and its interference with other modulatory systems are discussed together with the putative implications for neuronal function in physiological and pathological conditions. This article is part of a mini review series: 'Synaptic Function and Dysfunction in Brain Diseases'.
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Affiliation(s)
- Diogo M Rombo
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Joaquim A Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Ana M Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.,Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
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11
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Influence of General Anesthesia on Impulsivity and Learning Ability-Experimental Study. ACTA MEDICA MARISIENSIS 2016. [DOI: 10.1515/amma-2016-0045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Objective: To investigate the effect of anesthesia on rats’ ability of learning and over their impulsivity.
Material and Methods: We studied eight Wistar adult male rats, test and drug naive subjects. Animals were separated in two groups, group A and B with four members each. Group A included the anesthetized animals. The combination of ketamine, xylazine and piplophen in 2ml/kg body weight dosage was used and testing was done 24 hours after anesthesia. Group B was taken as control. The study was conducted using the ”Delay discounting” apparatus. Experiments assessing impulsive behavior were conducted using automated operant chambers, equipped with two nose-poke holes (holes where pellets of food were released). Rat’s answer was considered touching the nose-poke hole. One answer was rewarded with pellets of food of 45 mg each (small reward), while another hole released five pellets of 45 mg each (high reward). Both types of rewards were presented immediately after rat’s answer and were followed for a period of 25 seconds timeout. During the training phase, rats were placed in operant chambers 30 minutes per day, 5 consecutive days. The growing percent of preference for greater reward indicates learning. For the testing phase the procedure was similar, but a delay was introduced before the release of the big reward. During this phase, the preference for higher reward was indicative for non-impulsive behaviour.
Results: The results didn’t show significant statistically differences between the two groups.
Conclusions: Anesthesia had no effect on learning ability nor on impulsivity.
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Panlilio LV, Thorndike EB, Nikas SP, Alapafuja SO, Bandiera T, Cravatt BF, Makriyannis A, Piomelli D, Goldberg SR, Justinova Z. Effects of fatty acid amide hydrolase (FAAH) inhibitors on working memory in rats. Psychopharmacology (Berl) 2016; 233:1879-88. [PMID: 26558620 PMCID: PMC4846548 DOI: 10.1007/s00213-015-4140-6] [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: 09/21/2015] [Accepted: 10/29/2015] [Indexed: 11/24/2022]
Abstract
RATIONALE Manipulations of the endocannabinoid system could potentially produce therapeutic effects with minimal risk of adverse cannabis-like side effects. Inhibitors of fatty acid amide hydrolase (FAAH) increase endogenous levels of the cannabinoid-receptor agonist, anandamide, and show promise for treating a wide range of disorders. However, their effects on learning and memory have not been fully characterized. OBJECTIVES We determined the effects of five structurally different FAAH inhibitors in an animal model of working memory known to be sensitive to impairment by delta-9 tetrahydrocannabinol (THC). METHODS A delayed nonmatching-to-position procedure was used in rats. Illuminated nosepoke holes were used to provide sample cues (left versus right) and record responses (correct versus incorrect) after delays ranging from 0 to 28 s. Various test drugs were given acutely up to two times per week before daily sessions. RESULTS One FAAH inhibitor, AM3506 (3 mg/kg), decreased accuracy in the memory task. Four other FAAH inhibitors (URB597, URB694, PF-04457845, and ARN14633) and a monoacylglycerol lipase inhibitor (JZL184, which blocks the degradation of the endocannabinoid 2-arachidonoylglycerol) had no effect. Testing of AM3506 in combination with antagonists for receptors known to be affected by anandamide and other fatty acid amides indicated that the impairment induced by AM3506 was mediated by cannabinoid CB1 receptors, and not by alpha-type peroxisome proliferator-activated receptors (PPAR-alpha) or vanilloid transient receptor potential cation channels (TRPV1). CONCLUSIONS FAAH inhibitors differ with respect to their potential for memory impairment, abuse liability, and probably other cannabis-like effects, and they should be evaluated individually for specific therapeutic and adverse effects.
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Affiliation(s)
- Leigh V. Panlilio
- Preclinical Pharmacology Section, Behavioral Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Eric B. Thorndike
- Preclinical Pharmacology Section, Behavioral Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Spyros P. Nikas
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA, USA
| | | | - Tiziano Bandiera
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Benjamin F. Cravatt
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California, USA; Department of Chemical Physiology, The Scripps Research Institute, La Jolla, California 92037, USA
| | - Alexandros Makriyannis
- Center for Drug Discovery, Department of Pharmaceutical Sciences and Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Daniele Piomelli
- Drug Discovery and Development, Istituto Italiano di Tecnologia, Genoa, Italy; Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California, USA
| | - Steven R. Goldberg
- Preclinical Pharmacology Section, Behavioral Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, 21224, USA
| | - Zuzana Justinova
- Preclinical Pharmacology Section, Behavioral Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, 21224, USA
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13
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Ferré S, Sebastião AM. Dissecting striatal adenosine-cannabinoid receptor interactions. New clues from rats over-expressing adenosine A2A receptors. J Neurochem 2016; 136:897-9. [PMID: 26806455 DOI: 10.1111/jnc.13520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 12/22/2015] [Accepted: 12/23/2015] [Indexed: 01/25/2023]
Abstract
This Editorial highlights a study by Chiodi et al. () showing that the effects mediated by cannabinoid CB1 receptor (CB1R) activation in the striatum are significantly reduced in rats with neuronal over-expression of adenosine A2A receptors (A2AR). Two hypotheses are derived from that study. Hypothesis A: two subpopulations of pre-synaptic CB1R in corticostriatal glutamatergic terminals exist, one forming and another not forming heteromers with A2AR. Hypothesis B: CB1R are predominantly forming heteromers with A2AR. In the case of hypothesis A, the A2AR might be required for CB1R-A2AR heteromeric signaling, whereas non-heteromeric CB1R activity is inhibited by A2ARs. In the case of hypothesis B, up-regulation of A2ARs may perturb heteromeric stoichiometry, thus reducing CB1R functioning. In any case, pre-synaptic striatal A2AR-CB1R heteromers emerge as important targets of the effects of cannabinoids demonstrated at the neuronal and behavioral level. Read the highlighted article 'Striatal adenosine-cannabinoid receptor interactions in rats over-expressing adenosine A2A receptors' on page 907.
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Affiliation(s)
- Sergi Ferré
- Integrative Neurobiology Section, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD, USA
| | - Ana Maria Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.,Instituto de Medicina Molecular, Universidade de Lisboa, Lisbon, Portugal
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Developmentally vitamin D-deficient rats show enhanced prepulse inhibition after acute Δ9-tetrahydrocannabinol. Behav Pharmacol 2014; 25:236-44. [PMID: 24776491 DOI: 10.1097/fbp.0000000000000041] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Developmental vitamin D (DVD) deficiency has been proposed as a risk factor for schizophrenia. DVD-deficient rats show selective cognitive deficits and novelty-induced hyperlocomotion and enhanced locomotor responses from acute treatment with psychomimetic drugs, such as amphetamine and MK-801. Here we aimed to examine the effect of a drug from a different class of psychomimetic/psychoactive compounds, Δ9-tetrahydrocannabinol (THC), on tasks of relevance to the cognitive and positive symptoms of schizophrenia. The aim of this study was to investigate whether DVD deficiency modulates the behavioural effects of THC on tests of delay-dependent memory, sensorimotor gating and locomotion. Adult control and DVD-deficient rats were injected with THC (0, 0.3, 0.6, 1.25, 2.5 mg/kg) 15 min before a delay match to sample (DMTS) task using variable delays (0-24 s). A separate group of rats was injected with either 2.5 mg/kg THC or vehicle before tests of either prepulse inhibition (PPI) of the acoustic startle response or in the open field. Control and DVD-deficient rats showed a similar dose-dependent impairment in performance on the DMTS. The greatest impairment was observed at 2.5 mg/kg for all delays (0-24 s). DVD-deficient rats showed THC-induced enhancement of PPI, which was not observed in control rats. There was no effect of maternal diet on acoustic startle response or locomotor responses in the open field. This study reports the novel findings that DVD-deficient rats were more sensitive to the acute effects of THC on PPI. It appears that prenatal vitamin D deficiency has long-term effects on sensitivity to the behavioural effects of cannabinoids.
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15
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Sebastião AM, Ribeiro JA. Neuromodulation and metamodulation by adenosine: Impact and subtleties upon synaptic plasticity regulation. Brain Res 2014; 1621:102-13. [PMID: 25446444 DOI: 10.1016/j.brainres.2014.11.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 10/30/2014] [Accepted: 11/05/2014] [Indexed: 01/06/2023]
Abstract
Synaptic plasticity mechanisms, i.e. the sequence of events that underlies persistent changes in synaptic strength as a consequence of transient alteration in neuronal firing, are greatly influenced by the 'chemical atmosphere' of the synapses, that is to say by the presence of molecules at the synaptic cleft able to fine-tune the activity of other molecules more directly related to plasticity. One of those fine tuners is adenosine, known for a long time as an ubiquitous neuromodulator and metamodulator and recognized early as influencing synaptic plasticity. In this review we will refer to the mechanisms that adenosine can use to affect plasticity, emphasizing aspects of the neurobiology of adenosine relevant to its ability to control synaptic functioning. This article is part of a Special Issue entitled Brain and Memory.
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Affiliation(s)
- Ana M Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina e Unidade de Neurociências, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal.
| | - Joaquim A Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina e Unidade de Neurociências, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal.
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16
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Pesta DH, Angadi SS, Burtscher M, Roberts CK. The effects of caffeine, nicotine, ethanol, and tetrahydrocannabinol on exercise performance. Nutr Metab (Lond) 2013; 10:71. [PMID: 24330705 PMCID: PMC3878772 DOI: 10.1186/1743-7075-10-71] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 12/02/2013] [Indexed: 01/01/2023] Open
Abstract
Caffeine, nicotine, ethanol and tetrahydrocannabinol (THC) are among the most prevalent and culturally accepted drugs in western society. For example, in Europe and North America up to 90% of the adult population drinks coffee daily and, although less prevalent, the other drugs are also used extensively by the population. Smoked tobacco, excessive alcohol consumption and marijuana (cannabis) smoking are addictive and exhibit adverse health effects. These drugs are not only common in the general population, but have also made their way into elite sports because of their purported performance-altering potential. Only one of the drugs (i.e., caffeine) has enough scientific evidence indicating an ergogenic effect. There is some preliminary evidence for nicotine as an ergogenic aid, but further study is required; cannabis and alcohol can exhibit ergogenic potential under specific circumstances but are in general believed to be ergolytic for sports performance. These drugs are currently (THC, ethanol) or have been (caffeine) on the prohibited list of the World Anti-Doping Agency or are being monitored (nicotine) due to their potential ergogenic or ergolytic effects. The aim of this brief review is to evaluate the effects of caffeine, nicotine, ethanol and THC by: 1) examining evidence supporting the ergogenic or ergolytic effects; 2) providing an overview of the mechanism(s) of action and physiological effects; and 3) where appropriate, reviewing their impact as performance-altering aids used in recreational and elite sports.
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Affiliation(s)
- Dominik H Pesta
- Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA
- Department of Sports Science, Medical Section, University Innsbruck, Innsbruck, Austria
| | - Siddhartha S Angadi
- Healthy Lifestyles Research Center, School of Nutrition and Health Promotion, Arizona State University, Phoenix, AZ, USA
| | - Martin Burtscher
- Department of Sports Science, Medical Section, University Innsbruck, Innsbruck, Austria
| | - Christian K Roberts
- Exercise and Metabolic Disease Research Laboratory, Translational Sciences Section, School of Nursing, University of California, Los Angeles, CA, USA
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17
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Justinova Z, Mascia P, Wu HQ, Secci ME, Redhi GH, Panlilio LV, Scherma M, Barnes C, Parashos A, Zara T, Fratta W, Solinas M, Pistis M, Bergman J, Kangas BD, Ferré S, Tanda G, Schwarcz R, Goldberg SR. Reducing cannabinoid abuse and preventing relapse by enhancing endogenous brain levels of kynurenic acid. Nat Neurosci 2013; 16:1652-61. [PMID: 24121737 PMCID: PMC3835353 DOI: 10.1038/nn.3540] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 09/11/2013] [Indexed: 02/06/2023]
Abstract
In the reward circuitry of the brain, α-7-nicotinic acetylcholine receptors (α7nAChRs) modulate effects of Δ(9)-tetrahydrocannabinol (THC), marijuana's main psychoactive ingredient. Kynurenic acid (KYNA) is an endogenous negative allosteric modulator of α7nAChRs. Here we report that the kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 increases brain KYNA levels and attenuates cannabinoid-induced increases in extracellular dopamine in reward-related brain areas. In the self-administration model of drug abuse, Ro 61-8048 reduced the rewarding effects of THC and the synthetic cannabinoid WIN 55,212-2 in squirrel monkeys and rats, respectively, and it also prevented relapse to drug-seeking induced by reexposure to cannabinoids or cannabinoid-associated cues. The effects of enhancing endogenous KYNA levels with Ro 61-8048 were prevented by positive allosteric modulators of α7nAChRs. Despite a clear need, there are no medications approved for treatment of marijuana dependence. Modulation of KYNA offers a pharmacological strategy for achieving abstinence from marijuana and preventing relapse.
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Affiliation(s)
- Zuzana Justinova
- 1] Preclinical Pharmacology Section, Behavioral Neuroscience Research Branch, Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Department of Health and Human Services, Baltimore, Maryland, USA. [2] Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA. [3]
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18
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Klug M, van den Buuse M. An investigation into "two hit" effects of BDNF deficiency and young-adult cannabinoid receptor stimulation on prepulse inhibition regulation and memory in mice. Front Behav Neurosci 2013; 7:149. [PMID: 24155701 PMCID: PMC3800788 DOI: 10.3389/fnbeh.2013.00149] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 10/01/2013] [Indexed: 11/13/2022] Open
Abstract
Reduced brain-derived neurotrophic factor (BDNF) signaling has been shown in the frontal cortex and hippocampus in schizophrenia. The aim of the present study was to investigate whether a BDNF deficit would modulate effects of chronic cannabis intake, a well-described risk factor for schizophrenia development. BDNF heterozygous mice (HET) and wild-type controls were chronically treated during weeks 6, 7, and 8 of life with the cannabinoid receptor agonist, CP55,940 (CP). After a 2-week delay, there were no CP-induced deficits in any of the groups in short-term spatial memory in a Y-maze task or novel object recognition memory. Baseline prepulse inhibition (PPI) was lower but average startle was increased in BDNF HET compared to wild-type controls. Acute CP administration before the PPI session caused a marked increase in PPI in male HET mice pre-treated with CP but not in any of the other male groups. In females, there were small increases of PPI in all groups upon acute CP administration. Acute CP administration furthermore reduced startle and this effect was greater in HET mice irrespective of chronic CP pre-treatment. Analysis of the levels of [3H]CP55,940 binding by autoradiography revealed a significant increase in the nucleus accumbens of male BDNF HET mice previously treated with CP but not in any of the other groups or in the caudate nucleus. These results show that BDNF deficiency and chronic young-adult cannabinoid receptor stimulation do not interact in this model on learning and memory later in life. In contrast, male “two hit” mice, but not females, were hypersensitive to the effect of acute CP on sensorimotor gating. These effects may be related to a selective increase of [3H]CP55,940 binding in the nucleus accumbens, reflecting up-regulation of CB1 receptor density in this region. These data could be of relevance to our understanding of differential “two hit” neurodevelopmental mechanisms in schizophrenia.
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Affiliation(s)
- Maren Klug
- Behavioural Neuroscience Laboratory, Mental Health Research Institute Melbourne, VIC, Australia ; Department of Psychology, Swinburne University of Technology Hawthorn, VIC, Australia
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Sousa VC, Ribeiro JA, Sebastião AM. Caffeine and Adenosine Receptor Modulation of Cannabinoid Influence Upon Cognitive Function. JOURNAL OF CAFFEINE RESEARCH 2013. [DOI: 10.1089/jcr.2013.0010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Vasco C. Sousa
- Laboratory of Translational Neuropharmacology, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Joaquim A. Ribeiro
- Faculty of Medicine, Institute of Pharmacology and Neurosciences, University of Lisbon, Lisbon, Portugal
- Unit of Neurosciences, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal
| | - Ana M. Sebastião
- Faculty of Medicine, Institute of Pharmacology and Neurosciences, University of Lisbon, Lisbon, Portugal
- Unit of Neurosciences, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal
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20
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Steindel F, Lerner R, Häring M, Ruehle S, Marsicano G, Lutz B, Monory K. Neuron-type specific cannabinoid-mediated G protein signalling in mouse hippocampus. J Neurochem 2013; 124:795-807. [PMID: 23289830 DOI: 10.1111/jnc.12137] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 11/29/2012] [Accepted: 12/21/2012] [Indexed: 01/17/2023]
Abstract
Type 1 cannabinoid receptor (CB1) is expressed in different neuronal populations in the mammalian brain. In particular, CB1 on GABAergic or glutamatergic neurons exerts different functions and display different pharmacological properties in vivo. This suggests the existence of neuron-type specific signalling pathways activated by different subpopulations of CB1. In this study, we analysed CB1 expression, binding and signalling in the hippocampus of conditional mutant mice, bearing CB1 deletion in GABAergic (GABA-CB1-KO mice) or cortical glutamatergic neurons (Glu-CB1-KO mice). Compared to their wild-type littermates, Glu-CB1-KO displayed a small decrease of CB1 mRNA amount, immunoreactivity and [³H]CP55,940 binding. Conversely, GABA-CB1-KO mice showed a drastic reduction of these parameters, confirming that CB1 is present at much higher density on hippocampal GABAergic interneurons than glutamatergic neurons. Surprisingly, however, saturation analysis of HU210-stimulated [(35) S]GTPγS binding demonstrated that 'glutamatergic' CB1 is more efficiently coupled to G protein signalling than 'GABAergic' CB1. Thus, the minority of CB1 on glutamatergic neurons is paradoxically several fold more strongly coupled to G protein signalling than 'GABAergic' CB1. This selective signalling mechanism raises the possibility of designing novel cannabinoid ligands that differentially activate only a subset of physiological effects of CB1 stimulation, thereby optimizing therapeutic action.
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Affiliation(s)
- Frauke Steindel
- Institute of Physiological Chemistry, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
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