Effects of endocannabinoid neurotransmission modulators on brain stimulation reward Styliani Vlachou, George G. Nomikos & George Panagis Psychopharmacology, 2006, 188, 293–305 Doi : 10.1007/s00213-006-0506-0 Abstract Rationale : The endogenous cannabinoid system is responsive to the neurobiological actions of Δ9-tetrahydrocannabinol (THC) and other cannabinoid ligands. While numerous studies have focused on the behavioral and pharmacological effects of THC and cannabinoid agonists in experimental animals, most recent work focuses on compounds that modulate endocannabinoid neurotransmission. However, the relevant studies concerning the ability of endocannabinoid modulators to modify reward processes in experimental animals remain rather scarce. Objectives : The present study examined the effects of drugs modulating endocannabinoid neurotransmission on [...]
Lire la suiteThe Varieties of Psychedelic Epistemology Chris Letheby Published in N. Wyrd, D. Luke, A. Tollan, C. Adams, and D. King (eds.) : "Psychedelicacies: more food for thought from Breaking Convention", Strange Attractor Press, 2019. INTRODUCTION Is it possible to gain knowledge1 by taking psychedelic2 drugs? One influential answer is ‘yes’: according to this conception, by inducing mystical states of consciousness, psychedelics afford direct knowledge of supernatural, transcendent dimensions of reality. This is an entheogenic conception of the drugs as agents that “generate the divine within”. A second influential answer is ‘no’: since materialism or physicalism3 is true, there are no transcendent realities, and psychedelics [...]
Lire la suiteIn Vivo Availability of Cannabinoid 1 Receptor Levels in Patients With First-Episode Psychosis Faith Borgan, Heikki Laurikainen, Mattia Veronese, Tiago Reis Marques, Merja Haaparanta-Solin, Olof Solin, Tarik Dahoun, Maria Rogdaki, Raimo KR Salokangas, Max Karukivi, Marta Di Forti, Federico Turkheimer, Jarmo Hietala, Oliver Howes for the METSY Group JAMA Psychiatry, 2019. doi : 10.1001/jamapsychiatry.2019.1427 IMPORTANCE Experimental and epidemiological studies implicate the cannabinoid 1 receptor (CB1R) in the pathophysiology of psychosis. However, whether CB1R levels are altered in the early stages of psychosis and whether they are linked to cognitive function or symptom severity remain unknown. OBJECTIVE To investigate CB1R availability in first-episode psychosis (FEP) without the [...]
Lire la suiteLong-Term Effects of Cannabis on Brain Structure Giovanni Battistella, Eleonora Fornari, Jean-Marie Annoni, Haithem Chtioui, Kim Dao, Marie Fabritius, Bernard Favrat, Jean-Frederic Mall, Philippe Maeder and Christian Giroud Neuropsychopharmacology, 2014, 39, 2041–2048. doi:10.1038/npp.2014.67 Abstract The dose-dependent toxicity of the main psychoactive component of cannabis in brain regions rich in cannabinoid CB1 receptors is well known in animal studies. However, research in humans does not show common findings across studies regarding the brain regions that are affected after long-term exposure to cannabis. In the present study, we investigate (using Voxel-based Morphometry) gray matter changes in a group of regular cannabis smokers in comparison with a group of [...]
Lire la suiteRole of the Endocannabinoid System in the Pathophysiology of Schizophrenia M. Fakhoury Molecular Neurobiology, 2017, 54, (1), 768-778. doi: 10.1007/s12035-016-9697-5 ABSTRACT : The endocannabinoid system (ECS) is a group of neuromodulatory lipids, enzymes, and receptors involved in numerous behavioral and physiological processes such as mood, memory, and appetite. Recently, longitudinal and postmortem studies have shown that the ECS might be involved in neuropsychiatric disorders like schizophrenia. However, despite the large amount of research, our knowledge of the ECS and its implication in this debilitating disorder is still largely limited. This review aims at providing a comprehensive overview of the current state of knowledge of the [...]
Lire la suiteNeuroanatomical substrates involved in cannabinoid modulation of defensive responses F.A. Moreira, D.C. Aguiar, L.B. Resstel, S.F. Lisboa, A.C. Campos, F.V. Gomes and F.S. Guimaraes Journal of Psychopharmacology, 2012, 26, (1), 40–55 DOI: 10.1177/0269881111400651 Abstract Administration of Cannabis sativa derivatives causes anxiolytic or anxiogenic effects in humans and laboratory animals, depending on the specific compound and dosage used. In agreement with these findings, several studies in the last decade have indicated that the endocannabinoid system modulates neuronal activity in areas involved in defensive responses. The mechanisms of these effects, however, are still not clear. The present review summarizes recent data suggesting that they involve modulation of [...]
Lire la suiteBipolar disorder and the endocannabinoid system Shokouh Arjmand, Mina Behzadi, Kristi A. Kohlmeier, Shahrzad Mazhari, Abdolreza Sabahi and Mohammad Shabani Acta Neuropsychiatrica, 2019, 1-9. https://doi.org/10.1017/neu.2019.21 Abstract Objective : Bipolar disorder (BD) is a debilitating, lifelong neuropsychiatric illness characterised by unsteady mood states which vacillate from (hypo)mania to depression. Despite the availability of pharmaceutical agents which can be effective in ameliorating the acute affective symptoms and prevent episodic relapse, BD is inadequately treated in a subset of patients. The endocannabinoid system (ECS) is known to exert neuromodulatory effects on other neurotransmitter systems critical in governing emotions. Several studies ranging from clinical to molecular, as well as [...]
Lire la suiteRole of the Endocannabinoid System in the Pathophysiology of Schizophrenia: Implications for Pharmacological Intervention F.M. Leweke, J.K. Mueller, B.Lange, S. Fritze, C.E. Topor, D. Koethe, C. Rohleder CNS Drugs, 2018 Jul;32(7):605-619. doi: 10.1007/s40263-018-0539-z. Abstract The term schizophrenia describes a group of multifaceted psychiatric conditions causing significant impairment of the quality of life of affected patients. Although multiple pharmacological treatment options exist, e.g. first- or second-generation antipsychotics, these therapeutics often cause disturbing side effects, such as extrapyramidal symptoms, prolactin increase, sexual dysfunction and/or metabolic syndrome. Furthermore, cognitive impairments and negative symptoms, two factors significantly influencing the course and outcome, are not sufficiently addressed by the available [...]
Lire la suiteChildhood trauma and being at-risk for psychosis are associated with higher peripheral endocannabinoids E. Appiah-Kusi, R. Wilson, M.Colizzi, E. Foglia, Sagnik Bhattacharyya, et al. Psychological Medicine, 2019. DOI: https://doi.org/10.1017/S0033291719001946 Published online by Cambridge University Press: 19 August 2019 Abstract BackgroundEvidence has been accumulating regarding alterations in components of the endocannabinoid system in patients with psychosis. Of all the putative risk factors associated with psychosis, being at clinical high-risk for psychosis (CHR) has the strongest association with the onset of psychosis, and exposure to childhood trauma has been linked to an increased risk of development of psychotic disorder. We aimed to investigate whether being at-risk for [...]
Lire la suiteAmanita muscaria: chemistry, biology, toxicology, and ethnomycology Didier MICHELOT, Leda Maria MELENDEZ-HOWELL Mycological Research, 2003, 107, (2), 131-146. https://doi.org/10.1017/S0953756203007305 The fly agaric is a remarkable mushroom in many respects; these are its bearing, history, chemical components and the poisoning that it provokes when consumed. The ‘pantherina’ poisoning syndrome is characterized by central nervous system dysfunction. The main species responsible are Amanita muscaria and A. pantherina (Amanitaceae) ; however, some other species of the genus have been suspected for similar actions. Ibotenic acid and muscimol are the active components, and probably, some other substances detected in the latter species participate in the psychotropic effects. The [...]
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