Catégorie : Neurobiologie

Delta-9-tetrahydrocannabinol increases striatal glutamate levels in healthy individuals: implications for psychosis, Colizzi M. et al., 2019

Delta-9-tetrahydrocannabinol increases striatal glutamate levels in healthy individuals: implications for psychosis. Colizzi M., Weltens N., McGuire P., Lythgoe D., Williams S., Van Oudenhove L., Bhattacharyya S. Molecular Psychiatry, 2019 doi : 10.1038/s41380-019-0374-8. PMID : 30770892   Abstract The neurobiological mechanisms underlying the association between cannabis use and acute or long-lasting psychosis are not completely understood. While some evidence suggests altered striatal dopamine may underlie the association, direct evidence that cannabis use affects either acute or chronic striatal dopamine is inconclusive. In contrast, pre-clinical research suggests that cannabis may affect dopamine via modulation of glutamate signaling. A double-blind, randomized, placebo-controlled, crossover design was used to investigate whether [...]

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The effects of Δ9-tetrahydrocannabinol on the dopamine system, Michael A P Bloomfield et al., 2016

The effects of Δ9-tetrahydrocannabinol on the dopamine system Michael A P Bloomfield, Abhishekh H Ashok, Nora D Volkow, and Oliver D Howes Nature, 2016, 539, 7629, 369–377. doi : 10.1038/nature20153.   Preface Δ9-tetrahydrocannabinol (THC), the main psychoactive ingredient in cannabis, is a pressing concern to global mental health. Patterns of use are changing drastically due to legalisation, availability of synthetic analogues (‘spice’), cannavaping and aggrandizements in the purported therapeutic effects of cannabis. Many of THC’s reinforcing effects are mediated by the dopamine system. Due to complex cannabinoid-dopamine interactions there is conflicting evidence from human and animal research fields. Acute THC causes increased dopamine release and neuron [...]

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Clinical and Preclinical Evidence for Functional Interactions of Cannabidiol and Δ9-Tetrahydrocannabinol, Douglas L. Boggs et al., 2018

Clinical and Preclinical Evidence for Functional Interactions of Cannabidiol and Δ9-Tetrahydrocannabinol Douglas L. Boggs, Jacques D. Nguyen, Daralyn Morgenson, Michael A. Taffe and and Mohini Ranganathan Neuropsychopharmacology, 2018, 43, 142-154 Doi : 10.1038/npp.2017.209; published online 18 October 2017 Abstract The plant Cannabis sativa, commonly called cannabis or marijuana, has been used for its psychotropic and mind-altering side effects for millennia. There has been growing attention in recent years on its potential therapeutic efficacy as municipalities and legislative bodies in the United States, Canada, and other countries grapple with enacting policy to facilitate the use of cannabis or its constituents for medical purposes. There are >550 [...]

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Cannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment, Amir Englund et al., 2012

Cannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment Amir Englund, Paul D Morrison, Judith Nottage, Dominic Hague, Fergus Kane1, Stefania Bonaccorso1, James M Stone, Avi Reichenberg, Rudolf Brenneisen, David Holt, Amanda Feilding, Lucy Walker, Robin M Murray and Shitij Kapur Journal of Psychopharmacology, 2012 Doi : 10.1177/0269881112460109 Abstract Community-based studies suggest that cannabis products that are high in Δ9-tetrahydrocannabinol (THC) but low in cannabidiol (CBD) are particularly hazardous for mental health. Laboratory-based studies are ideal for clarifying this issue because THC and CBD can be administered in pure form, under controlled conditions. In a between-subjects design, we tested the hypothesis that pre-treatment with CBD inhibited [...]

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Cannabidiol enhances anandamide signaling and alleviates psychotic symptoms of schizophrenia, F. M. Leweke et al., 2012

Cannabidiol enhances anandamide signaling and alleviates psychotic symptoms of schizophrenia F. M. Leweke, D. Piomelli, F. Pahlisch, D. Muhl, C.W. Gerth, C. Hoyer, J. Klosterkötter, M. Hellmich and D. Koethe Translationnal Psychiatry, 2012, 2, e94 doi :10.1038/tp.2012.15; published online 20 March 2012 Abstract Cannabidiol is a component of marijuana that does not activate cannabinoid receptors, but moderately inhibits the degradation of the endocannabinoid anandamide. We previously reported that an elevation of anandamide levels in cerebrospinal fluid inversely correlated to psychotic symptoms. Furthermore, enhanced anandamide signaling let to a lower transition rate from initial prodromal states into frank psychosis as well as postponed transition. In [...]

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Multiple mechanisms involved in the large-spectrum therapeutic potential of cannabidiol in psychiatric disorders, Alline Cristina Campos et al., 2012,

Multiple mechanisms involved in the large-spectrum therapeutic potential of cannabidiol in psychiatric disorders Alline Cristina Campos, Fabricio Araujo Moreira, Felipe Villela Gomes, Elaine Aparecida Del Bel and Francisco Silveira Guimaraes Philosophical Transactions of The Royal Society Bulletin, 2012, 367, 3364–3378 doi:10.1098/rstb.2011.0389 Abstract Cannabidiol (CBD) is amajor phytocannabinoid present in the Cannabis sativa plant. It lacks the psychotomimetic and other psychotropic effects that the main plant compound D9 tetrahydrocannabinol (THC) being able, on the contrary, to antagonize these effects. This property, together with its safety profile, was an initial stimulus for the investigation of CBD pharmacological properties. It is now clear thatCBDhas therapeutic potential over a [...]

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Cannabidiol (CBD) as an Adjunctive Therapy in Schizophrenia : A Multicenter Randomized Controlled Trial, Philip Mc Guire et al., 2018

Cannabidiol (CBD) as an Adjunctive Therapy in Schizophrenia : A Multicenter Randomized Controlled Trial Philip Mc Guire, Philip Robson, Wieslaw Jerzy Cubala, Daniel Vasile, Paul Dugald Morrison, Rachel Barron, Adam Taylor, Stephen Wright, American Journal of Psychiatry, 2018, 175, 3, 225-231 https://doi.org/10.1176/appi.ajp.2017.17030325 Abstract Objective: Research in both animals and humans indicates that cannabidiol (CBD) has antipsychotic properties. The authors assessed the safety and effectiveness of CBD in patients with schizophrenia. Method: In an exploratory double-blind parallel-group trial, patients with schizophrenia were randomized in a 1:1 ratio to receive CBD (1000 mg/day; N=43) or placebo (N=45) alongside their existing antipsychotic medication. Participants were assessed before and after treatment using [...]

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CB2 receptor deletion on myeloid cells enhanced mechanical allodynia in a mouse model of neuropathic pain, Elisa Nent et al., 2019

CB2 receptor deletion on myeloid cells enhanced mechanical allodynia in a mouse model of neuropathic pain Elisa Nent, Chihiro Nozaki, Anne-Caroline Schmöle, David Otte & Andreas Zimmer www.nature.com/scientificreports, 2019, 9, 7468 https://doi.org/10.1038/s41598-019-43858-4 Abstract : Neuropathic pain can develop after nerve injury, leading to a chronic condition with spontaneous pain and hyperalgesia. Pain is typically restricted to the side of the injured nerve, but may occasionally spread to the contralateral side, a condition that is often referred to as mirror-image pain. Mechanisms leading to mirror-image pain are not completely understood, but cannabinoid CB2 receptors have been implicated. In this study, we use genetic mouse models to [...]

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Dissociable effects of cannabis with and without cannabidiol on the human brain’s resting-state functional connectivity, Matthew B Wall et al.,

Dissociable effects of cannabis with and without cannabidiol on the human brain’s resting-state functional connectivity Matthew B. Wall, Rebecca Pope, Tom P. Freeman, Oliwia S. Kowalczyk, Lysia Demetriou, Claire Mokrysz, Chandni Hindocha, Will Lawn, Michael A.P. Bloomfield, Abigail M. Freeman, Amanda Feilding, David J. Nutt and H. Valerie Curran Journal of Psychopharmacology,  2019, 1–9 DOI: 10.1177/0269881119841568 journals.sagepub.com/home/jop   Abstract Background : Two major constituents of cannabis are Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is the main psychoactive component; CBD may buffer the user against the harmful effects of THC. Aims : We examined the effects of two strains of cannabis and placebo on the human brain’s resting-state networks [...]

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