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Karunakaran KD, Pascale M, Ozana N, Potter K, Pachas GN, Evins AE, Gilman JM. Intoxication due to Δ9-tetrahydrocannabinol is characterized by disrupted prefrontal cortex activity. Neuropsychopharmacology 2024:10.1038/s41386-024-01876-5. [PMID: 38714786 DOI: 10.1038/s41386-024-01876-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 04/08/2024] [Accepted: 04/23/2024] [Indexed: 05/10/2024]
Abstract
Neural states of impairment from intoxicating substances, including cannabis, are poorly understood. Cannabinoid 1 receptors, the main target of Δ9-tetrahydrocannabinol (THC), the primary intoxicating cannabinoid in cannabis, are densely localized within prefrontal cortex; therefore, prefrontal brain regions are key locations to examine brain changes that characterize acute intoxication. We conducted a double-blind, randomized, cross-over study in adults, aged 18-55 years, who use cannabis regularly, to determine the effects of acute intoxication on prefrontal cortex resting-state measures, assessed with portable functional near-infrared spectroscopy. Participants received oral THC (10-80 mg, individually dosed to overcome tolerance and achieve acute intoxication) and identical placebo, randomized for order; 185 adults were randomized and 128 completed both study days and had usable data. THC was associated with expected increases in subjective intoxication ratings (ES = 35.30, p < 0.001) and heart rate (ES = 11.15, p = 0.001). THC was associated with decreased correlations and anticorrelations in static resting-state functional connectivity within the prefrontal cortex relative to placebo, with weakest correlations and anticorrelations among those who reported greater severity of intoxication (RSFC between medial PFC-ventromedial PFC and DEQ scores, r = 0.32, p < 0.001; RSFC between bilateral mPFC and DEQ scores, r = -0.28, p = 0.001). Relative to placebo, THC was associated with increased variability (or reduced stability) in dynamic resting-state functional connectivity of the prefrontal cortex at p = 0.001, consistent across a range of window sizes. Finally, using frequency power spectrum analyses, we observed that relative to placebo, THC was associated with widespread reduced spectral power within the prefrontal cortex across the 0.073-0.1 Hz frequency range at p < 0.039. These neural features suggest a disruptive influence of THC on the neural dynamics of the prefrontal cortex and may underlie cognitive impairing effects of THC that are detectable with portable imaging. This study is registered in Clinicaltrials.gov (NCT03655717).
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Affiliation(s)
- Keerthana Deepti Karunakaran
- Massachusetts General Hospital (MGH) Department of Psychiatry, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Michael Pascale
- Massachusetts General Hospital (MGH) Department of Psychiatry, Boston, MA, USA
| | - Nisan Ozana
- MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Faculty of Engineering and The Gonda Multidisciplinary Brain Research Center, Bar Ilan University, Ramat-Gan, 52900, Israel
| | - Kevin Potter
- Massachusetts General Hospital (MGH) Department of Psychiatry, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Gladys N Pachas
- Massachusetts General Hospital (MGH) Department of Psychiatry, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - A Eden Evins
- Massachusetts General Hospital (MGH) Department of Psychiatry, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Jodi M Gilman
- Massachusetts General Hospital (MGH) Department of Psychiatry, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
- MGH/HST Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.
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English A, Uittenbogaard F, Torrens A, Sarroza D, Slaven AVE, Piomelli D, Bruchas MR, Stella N, Land BB. A preclinical model of THC edibles that produces high-dose cannabimimetic responses. eLife 2024; 12:RP89867. [PMID: 38214701 PMCID: PMC10945583 DOI: 10.7554/elife.89867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024] Open
Abstract
No preclinical experimental approach enables the study of voluntary oral consumption of high-concentration Δ9-tetrahydrocannabinol (THC) and its intoxicating effects, mainly owing to the aversive response of rodents to THC that limits intake. Here, we developed a palatable THC formulation and an optimized access paradigm in mice to drive voluntary consumption. THC was formulated in chocolate gelatin (THC-E-gel). Adult male and female mice were allowed ad libitum access for 1 and 2 hr. Cannabimimetic responses (hypolocomotion, analgesia, and hypothermia) were measured following access. Levels of THC and its metabolites were measured in blood and brain tissue. Acute acoustic startle responses were measured to investigate THC-induced psychotomimetic behavior. When allowed access for 2 hr to THC-E-gel on the second day of a 3-day exposure paradigm, adult mice consumed up to ≈30 mg/kg over 2 hr, which resulted in robust cannabimimetic behavioral responses (hypolocomotion, analgesia, and hypothermia). Consumption of the same gelatin decreased on the following third day of exposure. Pharmacokinetic analysis shows that THC-E-gel consumption led to parallel accumulation of THC and its psychoactive metabolite, 11-OH-THC, in the brain, a profile that contrasts with the known rapid decline in brain 11-OH-THC levels following THC intraperitoneal (i.p.) injections. THC-E-gel consumption increased the acoustic startle response in males but not in females, demonstrating a sex-dependent effect of consumption. Thus, while voluntary consumption of THC-E-gel triggered equivalent cannabimimetic responses in male and female mice, it potentiated acoustic startle responses preferentially in males. We built a dose-prediction model that included cannabimimetic behavioral responses elicited by i.p. versus THC-E-gel to test the accuracy and generalizability of this experimental approach and found that it closely predicted the measured acoustic startle results in males and females. In summary, THC-E-gel offers a robust preclinical experimental approach to study cannabimimetic responses triggered by voluntary consumption in mice, including sex-dependent psychotomimetic responses.
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Affiliation(s)
- Anthony English
- Departments of Pharmacology, University of WashingtonSeattleUnited States
- UW Center of Excellence in Neurobiology of Addiction, Pain, and Emotion (NAPE), University of WashingtonSeattleUnited States
- Center for Cannabis Research, University of WashingtonSeattleUnited States
| | - Fleur Uittenbogaard
- Departments of Pharmacology, University of WashingtonSeattleUnited States
- UW Center of Excellence in Neurobiology of Addiction, Pain, and Emotion (NAPE), University of WashingtonSeattleUnited States
- Center for Cannabis Research, University of WashingtonSeattleUnited States
| | - Alexa Torrens
- Department of Anatomy & Neurobiology, University of California IrvineIrvineUnited States
| | - Dennis Sarroza
- Departments of Pharmacology, University of WashingtonSeattleUnited States
| | - Anna Veronica Elizabeth Slaven
- Departments of Pharmacology, University of WashingtonSeattleUnited States
- UW Center of Excellence in Neurobiology of Addiction, Pain, and Emotion (NAPE), University of WashingtonSeattleUnited States
| | - Daniele Piomelli
- Department of Anatomy & Neurobiology, University of California IrvineIrvineUnited States
| | - Michael R Bruchas
- Departments of Pharmacology, University of WashingtonSeattleUnited States
- UW Center of Excellence in Neurobiology of Addiction, Pain, and Emotion (NAPE), University of WashingtonSeattleUnited States
- Center for Cannabis Research, University of WashingtonSeattleUnited States
- Department of Anatomy & Neurobiology, University of California IrvineIrvineUnited States
- Department of Anesthesiology, University of WashingtonSeattleUnited States
| | - Nephi Stella
- Departments of Pharmacology, University of WashingtonSeattleUnited States
- UW Center of Excellence in Neurobiology of Addiction, Pain, and Emotion (NAPE), University of WashingtonSeattleUnited States
- Center for Cannabis Research, University of WashingtonSeattleUnited States
- Psychiatry & Behavioral Sciences, University of WashingtonSeattleUnited States
| | - Benjamin Bruce Land
- Departments of Pharmacology, University of WashingtonSeattleUnited States
- UW Center of Excellence in Neurobiology of Addiction, Pain, and Emotion (NAPE), University of WashingtonSeattleUnited States
- Center for Cannabis Research, University of WashingtonSeattleUnited States
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3
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Corli G, Tirri M, Bilel S, Giorgetti A, Bernardi T, Boccuto F, Borsari M, Giorgetti R, Marti M. Ethanol enhances JWH-018-induced impairment of sensorimotor and memory functions in mice: From preclinical evidence to forensic implication in Driving Under the Influence of Drugs. Drug Alcohol Depend 2023; 247:109888. [PMID: 37120918 DOI: 10.1016/j.drugalcdep.2023.109888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/03/2023] [Accepted: 04/14/2023] [Indexed: 05/02/2023]
Abstract
BACKGROUND Several new Synthetic Cannabinoids have appeared each year since their introduction into the illicit drug market as recreational drugs. Among these, naphtalen-1-yl-(1-pentylindol-3-yl) methanone (JWH-018) is one of the most detected compounds in biological samples from patients involved in intoxication or death cases. Furthermore, consumption of JWH-018 has been linked to several cases of Driving Under the Influence of Drugs (DUID) suggesting that effects induced by this compound can affect individuals' ability to drive. METHODS Given the high spread of polydrug consumption and the wide number of alcohol-related traffic accidents, this study aims to investigate the acute effects induced by co-administration of JWH-018 with ethanol on sensorimotor and motor responses, grip strength and memory functions in CD-1 male mice. Acute impairments induced by JWH-018 and ethanol alone have also been investigated, in order to compare their effects with that induced by their concurrent administration. RESULTS In vivo behavioral experiments revealed a worsening of the cognitive and sensorimotor disruption after the co-administration of JWH-018 with ethanol compared to single compounds. CONCLUSIONS These animal-based findings suggest a potential increased impairment on psychomotor performances which could be related to driving abilities posed by poly-drug consumption involving SCs and ethanol.
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Affiliation(s)
- Giorgia Corli
- Department of Translational Medicine, Section of Legal Medicine, LTTA Center and University Center of Gender Medicine, University of Ferrara, Ferrara, Italy
| | - Micaela Tirri
- Department of Translational Medicine, Section of Legal Medicine, LTTA Center and University Center of Gender Medicine, University of Ferrara, Ferrara, Italy
| | - Sabrine Bilel
- Department of Translational Medicine, Section of Legal Medicine, LTTA Center and University Center of Gender Medicine, University of Ferrara, Ferrara, Italy
| | - Arianna Giorgetti
- Department of Medical and Surgical Sciences, Unit of Legal Medicine, University of Bologna, Via Irnerio 49, Bologna, 40126, Italy
| | - Tatiana Bernardi
- Department of Environmental Sciences and Prevention, University of Ferrara, Ferrara, 44121, Italy
| | - Federica Boccuto
- Department of Translational Medicine, Section of Legal Medicine, LTTA Center and University Center of Gender Medicine, University of Ferrara, Ferrara, Italy
| | - Martina Borsari
- Department of Translational Medicine, Section of Legal Medicine, LTTA Center and University Center of Gender Medicine, University of Ferrara, Ferrara, Italy
| | - Raffaele Giorgetti
- Department of Excellence of Biomedical Science and Public Health, Faculty of Medicine, Polytechnic University of Marche, Ancona, Italy
| | - Matteo Marti
- Department of Translational Medicine, Section of Legal Medicine, LTTA Center and University Center of Gender Medicine, University of Ferrara, Ferrara, Italy; Collaborative Center for the Italian National Early Warning System, Department of Anti-Drug Policies, Presidency of the Council of Ministers, Italy.
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4
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Wiebe A, Kannen K, Selaskowski B, Mehren A, Thöne AK, Pramme L, Blumenthal N, Li M, Asché L, Jonas S, Bey K, Schulze M, Steffens M, Pensel MC, Guth M, Rohlfsen F, Ekhlas M, Lügering H, Fileccia H, Pakos J, Lux S, Philipsen A, Braun N. Virtual reality in the diagnostic and therapy for mental disorders: A systematic review. Clin Psychol Rev 2022; 98:102213. [PMID: 36356351 DOI: 10.1016/j.cpr.2022.102213] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 08/21/2022] [Accepted: 10/11/2022] [Indexed: 01/27/2023]
Abstract
BACKGROUND Virtual reality (VR) technologies are playing an increasingly important role in the diagnostics and treatment of mental disorders. OBJECTIVE To systematically review the current evidence regarding the use of VR in the diagnostics and treatment of mental disorders. DATA SOURCE Systematic literature searches via PubMed (last literature update: 9th of May 2022) were conducted for the following areas of psychopathology: Specific phobias, panic disorder and agoraphobia, social anxiety disorder, generalized anxiety disorder, posttraumatic stress disorder (PTSD), obsessive-compulsive disorder, eating disorders, dementia disorders, attention-deficit/hyperactivity disorder, depression, autism spectrum disorder, schizophrenia spectrum disorders, and addiction disorders. ELIGIBILITY CRITERIA To be eligible, studies had to be published in English, to be peer-reviewed, to report original research data, to be VR-related, and to deal with one of the above-mentioned areas of psychopathology. STUDY EVALUATION For each study included, various study characteristics (including interventions and conditions, comparators, major outcomes and study designs) were retrieved and a risk of bias score was calculated based on predefined study quality criteria. RESULTS Across all areas of psychopathology, k = 9315 studies were inspected, of which k = 721 studies met the eligibility criteria. From these studies, 43.97% were considered assessment-related, 55.48% therapy-related, and 0.55% were mixed. The highest research activity was found for VR exposure therapy in anxiety disorders, PTSD and addiction disorders, where the most convincing evidence was found, as well as for cognitive trainings in dementia and social skill trainings in autism spectrum disorder. CONCLUSION While VR exposure therapy will likely find its way successively into regular patient care, there are also many other promising approaches, but most are not yet mature enough for clinical application. REVIEW REGISTRATION PROSPERO register CRD42020188436. FUNDING The review was funded by budgets from the University of Bonn. No third party funding was involved.
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Affiliation(s)
- Annika Wiebe
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Kyra Kannen
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Benjamin Selaskowski
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Aylin Mehren
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Ann-Kathrin Thöne
- School of Child and Adolescent Cognitive Behavior Therapy (AKiP), Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Lisa Pramme
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Nike Blumenthal
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Mengtong Li
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Laura Asché
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Stephan Jonas
- Institute for Digital Medicine, University Hospital Bonn, Bonn, Germany
| | - Katharina Bey
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Marcel Schulze
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Maria Steffens
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Max Christian Pensel
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Matthias Guth
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Felicia Rohlfsen
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Mogda Ekhlas
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Helena Lügering
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Helena Fileccia
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Julian Pakos
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Silke Lux
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Alexandra Philipsen
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany
| | - Niclas Braun
- Department of Psychiatry and Psychotherapy, University Hospital Bonn, Bonn, Germany.
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5
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Remy I, Schwitzer T, Albuisson É, Schwan R, Krieg J, Bernardin F, Ligier F, Lalanne L, Maillard L, Laprevote V. Impaired P100 among regular cannabis users in response to magnocellular biased visual stimuli. Prog Neuropsychopharmacol Biol Psychiatry 2022; 113:110437. [PMID: 34520807 DOI: 10.1016/j.pnpbp.2021.110437] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 08/30/2021] [Accepted: 09/08/2021] [Indexed: 01/10/2023]
Abstract
Regular cannabis using causes vision impairment by affecting human retinal neurotransmission. However, studies less considered its impact on the subsequent visual cortical processing, key feature for the integration of the visual signal in brain. We aimed at investigating this purpose in regular cannabis users using spatial frequencies and temporal frequencies filtered visual stimuli. We recruited 45 regular cannabis users and 25 age-matched controls. We recorded visual evoked potentials during the projection of low spatial frequency (0.5 cycles/degree) or high spatial frequency gratings (15 cycles/degree), which were presented statically (0 Hz) or dynamically (8 Hz). We analyzed the amplitude, latency, and area under the curve of both P100 and N170, best EEG markers for early visual processing. Data were compared between groups by repeated measures ANCOVA. Results showed a significant decrease in P100 amplitude among regular cannabis users in low spatial frequency (F(1,67) = 4.43; p = 0.04) and in dynamic condition (F(1,67) = 4.35; p = 0.04). Analysis also reported a decrease in P100 area under the curve in regular cannabis users to low spatial frequency (F(1,67) = 4.31; p = 0.04) and in dynamic condition (F(1,67) = 7.65; p < 0.01). No effect was found on P100 latency, N170 amplitude, latency, or area under the curve. We found alteration of P100 responses to low spatial frequency and dynamic stimuli in regular cannabis users. This result could be interpreted as a preferential magnocellular impairment where such deficit could be linked to glutamatergic dysfunction. As mentioned in the literature, visual and electrophysiological anomalies in schizophrenia are related to a magnocellular dysfunction. Further studies are needed to clarify electrophysiological deficits in both populations. CLINICAL TRIALS REGISTRATION: Electrophysiological Study of the Functioning of Magnocellular Visual Pathway in Regular Cannabis Users (CAUSA MAP). [NCT02864680; ID 2013-A00097-38]. https://clinicaltrials.gov/ct2/show/NCT02864680?cond=Cannabis&cntry=FR&draw=2&rank=1.
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Affiliation(s)
- Irving Remy
- Centre Psychothérapique de Nancy, Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes du Grand Nancy, Laxou F-54520, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Département de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, F-67200, France; BioSerenity - 47, Boulevard de l'Hôpital, ICM-IPEPS, 75013, Paris, France
| | - Thomas Schwitzer
- Centre Psychothérapique de Nancy, Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes du Grand Nancy, Laxou F-54520, France; Université de Lorraine, Faculté de Médecine, Vandœuvre-lès-Nancy F-54505, France; Université de Lorraine, IADI, INSERM U1254, Vandœuvre-lès-Nancy, F-54511, France
| | - Éliane Albuisson
- Unité de méthodologie, Gestion des données statistiques, Centre Hospitalier Régional Universitaire de Nancy, DRCI, Département MPI, UMDS, F-54000 Nancy, France; Université de Lorraine, Faculté de Médecine, Département du Grand Est de Recherche en Soins Primaires (DEGERESP), F-54000 Nancy, France; Université de Lorraine, CNRS, Institut Élie-Cartan de Lorraine, F-54000 Nancy, France
| | - Raymund Schwan
- Centre Psychothérapique de Nancy, Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes du Grand Nancy, Laxou F-54520, France; Université de Lorraine, Faculté de Médecine, Vandœuvre-lès-Nancy F-54505, France; Université de Lorraine, IADI, INSERM U1254, Vandœuvre-lès-Nancy, F-54511, France
| | - Julien Krieg
- Centre Psychothérapique de Nancy, Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes du Grand Nancy, Laxou F-54520, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Département de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, F-67200, France
| | - Florent Bernardin
- Centre Psychothérapique de Nancy, Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes du Grand Nancy, Laxou F-54520, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Département de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, F-67200, France
| | - Fabienne Ligier
- Centre Psychothérapique de Nancy, Pôle Universitaire de Psychiatrie de l'Enfant et de l'Adolescent, Laxou F-54520, France; Université de Lorraine, EA 4360 APEMAC, Equipe MICS, F-54000, France; Université de Lorraine, EA 4432 InterPsy, Equipe PRISME, F-54000, France
| | - Laurence Lalanne
- INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Département de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, F-67200, France; Unité de Psychiatrie et d'Addictologie, Fédération de Médecine Translationnelle de Strasbourg, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, F-67200, France
| | - Louis Maillard
- Université de Lorraine, CNRS, CRAN, UMR 7039, F-54500, Nancy, France; Service de Neurologie, Centre Hospitalier Régional Universitaire de Nancy, Nancy F-54000, France
| | - Vincent Laprevote
- Centre Psychothérapique de Nancy, Pôle Hospitalo-Universitaire de Psychiatrie d'Adultes du Grand Nancy, Laxou F-54520, France; INSERM U1114, Fédération de Médecine Translationnelle de Strasbourg, Département de Psychiatrie, Centre Hospitalier Régional Universitaire de Strasbourg, Strasbourg, F-67200, France; Université de Lorraine, Faculté de Médecine, Vandœuvre-lès-Nancy F-54505, France.
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6
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Brown JD, Rivera Rivera KJ, Hernandez LYC, Doenges MR, Auchey I, Pham T, Goodin AJ. Natural and Synthetic Cannabinoids: Pharmacology, Uses, Adverse Drug Events, and Drug Interactions. J Clin Pharmacol 2021; 61 Suppl 2:S37-S52. [PMID: 34396558 DOI: 10.1002/jcph.1871] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 04/01/2021] [Indexed: 01/15/2023]
Abstract
The purpose of this narrative review is to describe the current use environment of both natural and synthetic cannabinoids while providing context for cannabinoid chemistry and pharmacology. In addition to a long history of recreational and nonmedical use, natural cannabinoids are increasingly used as prescription products, through medical cannabis programs, and as consumer health products. Despite anecdotal safety evidence, cannabis and cannabinoids are pharmacologically complex and pose risks for adverse drug events and drug-drug interactions. Synthetic cannabinoids, particularly agonists of cannabinoid receptors, are more potent than natural cannabinoids and can lead to more severe reactions and medical emergencies. This review provides a summary of approved uses and an overview of mechanisms of action for adverse drug events with natural and synthetic cannabinoids. Clinical considerations for special populations that may be at heightened risk for drug-drug interactions and adverse drug events while using natural or synthetic cannabinoids are examined, and recommendations are provided.
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Affiliation(s)
- Joshua D Brown
- Center for Drug Evaluation & Safety, University of Florida, Gainesville, Florida, USA.,Consortium for Medical Marijuana Clinical Outcomes Research, University of Florida, Gainesville, Florida, USA.,Department of Pharmaceutical Outcomes & Policy, University of Florida College of Pharmacy, Gainesville, Florida, USA
| | | | | | - Matthew R Doenges
- University of Florida College of Pharmacy, Gainesville, Florida, USA
| | - India Auchey
- University of Florida College of Pharmacy, Gainesville, Florida, USA
| | - Thanh Pham
- University of Florida College of Pharmacy, Gainesville, Florida, USA
| | - Amie J Goodin
- Center for Drug Evaluation & Safety, University of Florida, Gainesville, Florida, USA.,Consortium for Medical Marijuana Clinical Outcomes Research, University of Florida, Gainesville, Florida, USA.,Department of Pharmaceutical Outcomes & Policy, University of Florida College of Pharmacy, Gainesville, Florida, USA
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7
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Gunasekera B, Davies C, Martin-Santos R, Bhattacharyya S. The Yin and Yang of Cannabis: A Systematic Review of Human Neuroimaging Evidence of the Differential Effects of Δ 9-Tetrahydrocannabinol and Cannabidiol. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2021; 6:636-645. [PMID: 33414100 DOI: 10.1016/j.bpsc.2020.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/14/2020] [Accepted: 10/19/2020] [Indexed: 12/23/2022]
Abstract
Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) have been the most investigated cannabinoids at the human and preclinical levels, although the neurobiological mechanisms underlying their effects remain unclear. Human experimental evidence complemented by observational studies suggests that THC may have psychotogenic effects while CBD may have antipsychotic effects. However, whether their effects on brain function are consistent with their opposing behavioral effects remains unclear. To address this, here we synthesize neuroimaging evidence investigating the acute effects of THC and CBD on human brain function using a range of neuroimaging techniques, with an aim to identify the key brain substrates where THC and CBD have opposing effects. After a systematic search, a review of the available studies indicated marked heterogeneity. However, an overall pattern of opposite effect profiles of the two cannabinoids was evident with some degree of consistency, primarily attributed to the head-to-head challenge studies of THC and CBD. While head-to-head comparisons are relatively few, collectively the evidence suggests that opposite effects of THC and CBD may be present in the striatum, parahippocampus, anterior cingulate/medial prefrontal cortex, and amygdala, with opposite effects less consistently identified in other regions. Broadly, THC seems to increase brain activation and blood flow, whereas CBD seems to decrease brain activation and blood flow. Given the sparse evidence, there is a particular need to understand the mechanisms underlying their opposite behavioral effects because it may not only offer insights into the underlying pathophysiological mechanisms of psychotic disorders but also suggest potentially novel targets and biomarkers for drug discovery.
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Affiliation(s)
- Brandon Gunasekera
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - Cathy Davies
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - Rocio Martin-Santos
- Department of Medicine, Institute of Neuroscience, University of Barcelona, Spain
| | - Sagnik Bhattacharyya
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom.
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8
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The why behind the high: determinants of neurocognition during acute cannabis exposure. Nat Rev Neurosci 2021; 22:439-454. [PMID: 34045693 DOI: 10.1038/s41583-021-00466-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/12/2021] [Indexed: 11/08/2022]
Abstract
Acute cannabis intoxication may induce neurocognitive impairment and is a possible cause of human error, injury and psychological distress. One of the major concerns raised about increasing cannabis legalization and the therapeutic use of cannabis is that it will increase cannabis-related harm. However, the impairing effect of cannabis during intoxication varies among individuals and may not occur in all users. There is evidence that the neurocognitive response to acute cannabis exposure is driven by changes in the activity of the mesocorticolimbic and salience networks, can be exacerbated or mitigated by biological and pharmacological factors, varies with product formulations and frequency of use and can differ between recreational and therapeutic use. It is argued that these determinants of the cannabis-induced neurocognitive state should be taken into account when defining and evaluating levels of cannabis impairment in the legal arena, when prescribing cannabis in therapeutic settings and when informing society about the safe and responsible use of cannabis.
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Zhornitsky S, Pelletier J, Assaf R, Giroux S, Li CSR, Potvin S. Acute effects of partial CB 1 receptor agonists on cognition - A meta-analysis of human studies. Prog Neuropsychopharmacol Biol Psychiatry 2021; 104:110063. [PMID: 32791166 DOI: 10.1016/j.pnpbp.2020.110063] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/05/2020] [Accepted: 08/05/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND Impairment in cognition is frequently associated with acute cannabis consumption. However, some questions remain unanswered as to which deficits are most prominent and which demographic groups are most vulnerable. METHODS A literature search yielded 52 experimental studies of acute administration of partial CB1 receptor agonists (i.e. cannabis, THC, and nabilone) that assessed cognitive dysfunction in 1580 healthy volunteers. Effect size estimates were calculated using the Comprehensive Meta-Analysis for the following six cognitive domains: attention, executive functions, impulsivity, speed of processing, verbal learning/memory, and working memory. RESULTS There were small-to-moderate impairments across all cognitive domains. Deficits in verbal learning/memory and working memory were more prominent, whereas attention and impulsivity were the least affected. Meta-regression analysis revealed that the greater the male ratio is in a sample, the greater the negative effect of cannabinoids on speed of processing and impulsivity. Analysis of route of administration showed that the deficits in speed of processing were smaller in the oral, relative to smoking, vaping, and intravenous administration studies. A publication bias was observed. DISCUSSION Verbal learning/memory and working memory are most prominently affected by acute administration of partial CB1 receptor agonists. The results are consistent with the residual cognitive effects that have been documented among chronic cannabis users.
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Affiliation(s)
- Simon Zhornitsky
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, United States of America
| | - Julie Pelletier
- Department of Psychiatry, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Roxane Assaf
- Department of Psychiatry, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada; Centre de recherche de l'Institut Universitaire en Santé Mentale de Montréal, Montreal, QC, Canada
| | - Sarah Giroux
- Department of Psychology, Université de Montréal, Montréal, QC, Canada
| | - Chiang-Shan R Li
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06519, United States of America; Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06520, United States of America; Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT 06520, United States of America
| | - Stephane Potvin
- Department of Psychiatry, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada; Centre de recherche de l'Institut Universitaire en Santé Mentale de Montréal, Montreal, QC, Canada.
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10
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DeFilippis EM, Bajaj NS, Singh A, Malloy R, Givertz MM, Blankstein R, Bhatt DL, Vaduganathan M. Marijuana Use in Patients With Cardiovascular Disease: JACC Review Topic of the Week. J Am Coll Cardiol 2020; 75:320-332. [PMID: 31976871 PMCID: PMC7977484 DOI: 10.1016/j.jacc.2019.11.025] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 10/29/2019] [Accepted: 11/12/2019] [Indexed: 12/17/2022]
Abstract
Marijuana use is increasing as more states are legalizing cannabis for both medicinal and recreational purposes. National survey data estimate that >2 million Americans with established cardiovascular diseases currently use or have used marijuana in its variety of forms, including inhalation and vaping. Cannabinoid receptors are distributed in multiple tissue beds and cells, including platelets, adipose tissue, and myocytes. Observational data suggest associations between marijuana and a broad range of adverse cardiovascular risks. Marijuana is becoming increasingly potent, and smoking marijuana carries many of the same cardiovascular health hazards as smoking tobacco. Synthetic cannabinoids have been linked to more sustained and deleterious pharmacodynamic effects. Marijuana is classified as a Schedule I substance, thus limiting its rigorous study for cardiovascular health effects. This review summarizes cardiovascular considerations related to marijuana use, pharmacological interactions, and future steps to provide clearer guidance regarding its cardiovascular safety. Screening for marijuana use is encouraged, especially in young patients presenting with cardiovascular disease.
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Affiliation(s)
- Ersilia M DeFilippis
- Columbia University Irving Medical Center, New York, New York. https://twitter.com/ersied727
| | - Navkaranbir S Bajaj
- University of Alabama at Birmingham, Birmingham, Alabama. https://twitter.com/bajaj_nav
| | - Amitoj Singh
- Sarver Heart Center, University of Arizona, Tucson, Arizona
| | - Rhynn Malloy
- Brigham and Women's Hospital Heart & Vascular Center and Harvard Medical School, Boston, Massachusetts
| | - Michael M Givertz
- Brigham and Women's Hospital Heart & Vascular Center and Harvard Medical School, Boston, Massachusetts
| | - Ron Blankstein
- Brigham and Women's Hospital Heart & Vascular Center and Harvard Medical School, Boston, Massachusetts. https://twitter.com/RonBlankstein
| | - Deepak L Bhatt
- Brigham and Women's Hospital Heart & Vascular Center and Harvard Medical School, Boston, Massachusetts. https://twitter.com/DLBHATTMD
| | - Muthiah Vaduganathan
- Brigham and Women's Hospital Heart & Vascular Center and Harvard Medical School, Boston, Massachusetts.
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11
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Withey SL, Bergman J, Huestis MA, George SR, Madras BK. THC and CBD blood and brain concentrations following daily administration to adolescent primates. Drug Alcohol Depend 2020; 213:108129. [PMID: 32593153 PMCID: PMC7371526 DOI: 10.1016/j.drugalcdep.2020.108129] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Cannabis availability with high concentrations of Δ-9-tetrahydrocannabinol (THC) and a range of THC to cannabidiol (CBD) ratios has increased in parallel with a rise in daily cannabis consumption by adolescents. Unanswered questions in adolescents include: 1) whether THC blood concentrations and THC metabolites remain stable or change with prolonged daily dosing, 2) whether CBD modulates THC pharmacokinetic properties and alters THC accumulation in brain, 3) whether blood THC levels reflect brain concentrations. METHODS In adolescent squirrel monkeys (Saimiri boliviensis), we determined whether a four-month regimen of daily THC (1 mg/kg) or CBD (3 mg/kg) + THC (1 mg/kg) administration (IM) affects THC, THC metabolites, and CBD concentrations in blood or brain. RESULTS Blood THC concentrations, THC metabolites and CBD remained stable during chronic treatment. 24 h after the final THC or CBD + THC injection, blood THC and CBD concentrations remained relatively high (THC: 6.0-11 ng/mL; CBD: 9.7-19 ng/mL). THC concentrations in cerebellum and occipital cortex were approximately twice those in blood 24 h after the last dose and did not significantly differ in subjects given THC or CBD + THC. CONCLUSIONS In adolescent monkeys, blood levels of THC, its metabolites or CBD remain stable after daily dosing for four months. Our model suggests that any pharmacological interactions between CBD and THC are unlikely to result from CBD modulation of THC pharmacokinetics. Finally, detection of relatively high brain THC concentrations 24 h after the final dose of THC suggests that the prolonged actions of THC may contribute to persistent cognitive and psychomotor disruption after THC- or cannabis-induced euphoria wane.
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Affiliation(s)
- SL Withey
- Laboratory of Addiction Neurobiology, McLean Hospital, 115 Mill St, Belmont, MA 02478, USA; Department of Psychiatry, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA
| | - J Bergman
- Behavioral Biology Program, McLean Hospital, 115 Mill St, Belmont, MA 02478, USA; Department of Psychiatry, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA
| | - MA Huestis
- Institute of Emerging Health Professions, Thomas Jefferson University, 130 S. 9th Street Philadelphia, PA 19107
| | - SR George
- Department of Pharmacology, University of Toronto, Toronto, ON, M5S 1A8, Canada; Department of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - BK Madras
- Laboratory of Addiction Neurobiology, McLean Hospital, 115 Mill St, Belmont, MA 02478, USA; Department of Psychiatry, Harvard Medical School, 25 Shattuck St, Boston, MA 02115, USA
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12
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Bindesri SD, Jebailey R, Albarghouthi N, Pye CC, Brosseau CL. Spectroelectrochemical and computational studies of tetrahydrocannabinol (THC) and carboxy-tetrahydrocannabinol (THC-COOH). Analyst 2020; 145:1849-1857. [DOI: 10.1039/c9an02173f] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electrochemical SERS allows for the rapid detection of both THC and THC-COOH in bodily fluid matrices without interferences from matrix species, paving the way to a point-of-need tool for cannabinoid detection.
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Affiliation(s)
| | | | | | - Cory C. Pye
- Department of Chemistry
- Saint Mary's University
- Halifax
- Canada
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13
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Mason NL, Theunissen EL, Hutten NRPW, Tse DHY, Toennes SW, Stiers P, Ramaekers JG. Cannabis induced increase in striatal glutamate associated with loss of functional corticostriatal connectivity. Eur Neuropsychopharmacol 2019; 29:247-256. [PMID: 30553697 DOI: 10.1016/j.euroneuro.2018.12.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/28/2018] [Accepted: 12/01/2018] [Indexed: 12/22/2022]
Abstract
Cannabis is the most commonly used illicit drug and is known to alter state of consciousness and impair neurocognitive function. However, the mechanisms underlying these effects have yet to be fully elucidated. Rodent studies suggest that Δ9-tetrahydrocannabinol (THC) activates dopaminergic neurons in the limbic system, subsequently enhancing dopamine, which is implicated in the rewarding effects of cannabis. Additional evidence suggests that THC may act indirectly on dopamine firing by modulating GABA and glutamate release. This double-blind, placebo-controlled study assessed the acute influence of two doses of THC on brain kinetics of glutamate, GABA, and dopamine, in relation to behavioral outcomes, by using magnetic resonance spectroscopy and functional magnetic resonance imaging. Twenty occasional cannabis users received acute doses of cannabis (300 µg/kg THC) and placebo, in one of two dose regimes (full dose and divided dose), during two separate testing days. Administration of THC increased striatal glutamate concentrations, and dopamine as indicated by a reduction in functional connectivity (FC) between the nucleus accumbens (NAc) and cortical areas. Alterations in glutamate and FC were dose dependent and evident in the full dose group where THC serum concentrations exceeded 2 ng/ml at T-max. Average glutamate changes correlated strongly with FC alterations. Additionally, THC induced changes in FC correlated with feelings of subjective high and decreased performance on an attention task. Taken together, this suggests that THC elicits subjective and cognitive alterations via increased striatal dopaminergic activity and loss of corticostriatal connectivity, which is associated with an increase in striatal glutamate.
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Affiliation(s)
- Natasha L Mason
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
| | - Eef L Theunissen
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Nadia R P W Hutten
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Desmond H Y Tse
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Stefan W Toennes
- Institute of Legal Medicine, University of Frankfurt, Kennedyallee 104, D-60596, Frankfurt/Main, Germany
| | - Peter Stiers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
| | - Johannes G Ramaekers
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD, Maastricht, The Netherlands
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14
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Evaluation of Task-Related Brain Activity: Is There a Role for 18F FDG-PET Imaging? BIOMED RESEARCH INTERNATIONAL 2019; 2019:4762404. [PMID: 31355263 PMCID: PMC6634077 DOI: 10.1155/2019/4762404] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 02/03/2019] [Accepted: 06/12/2019] [Indexed: 12/22/2022]
Abstract
Positron emission tomography (PET) with 2-[18F]-fluorodeoxyglucose (FDG) has been widely used for the evaluation of cortical glucose metabolism in several neurodegenerative disorders while its potential role in the evaluation of cortical and subcortical activity during a task in the healthy and pathological brain still remains to be a matter of debate. Few studies have been carried out in order to investigate the potential role of this radiotracer for the evaluation of brain glucose consumption during dynamic brain activation. The aim of this review is to provide a general overview of the applications of FDG-PET in the evaluation of cortical activation at rest and during tasks, describing first the physiological basis of FDG distribution in brain and its kinetic in vivo. An overview of the imaging protocols and image interpretation will be provided as well. As a last aspect, the results of the main studies in this field will be summarized and the results of PET findings performed in healthy subjects and patients suffering from various diseases will be reported.
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15
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Bhattacharyya S, Sainsbury T, Allen P, Nosarti C, Atakan Z, Giampietro V, Brammer M, McGuire PK. Increased hippocampal engagement during learning as a marker of sensitivity to psychotomimetic effects of δ-9-THC. Psychol Med 2018; 48:2748-2756. [PMID: 29502548 DOI: 10.1017/s0033291718000387] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND Cannabis and its main psychoactive ingredient δ-9-tetrahydrocannibidiol (THC) can induce transient psychotic symptoms in healthy individuals and exacerbate them in those with established psychosis. However, not everyone experience these effects, suggesting that certain individuals are particularly susceptible. The neural basis of this sensitivity to the psychotomimetic effects of THC is unclear. METHODS We investigated whether individuals who are sensitive to the psychotomimetic effects of THC (TP) under experimental conditions would show differential hippocampal activation compared with those who are not (NP). We studied 36 healthy males under identical conditions under the influence of placebo or THC (10 mg) given orally, on two separate occasions, in a pseudo-randomized, double-blind, repeated measures, within-subject, cross-over design, using psychopathological assessments and functional MRI while they performed a verbal learning task. They were classified into those who experienced transient psychotic symptoms (TP; n = 14) following THC administration and those who did not (NP; n = 22). RESULTS Under placebo conditions, there was significantly greater engagement of the left hippocampus (p < 0.001) in the TP group compared with the NP group during verbal encoding, which survived leave-one-out analysis. The level of hippocampal activation was directly correlated (Spearman's ρ = 0.44, p = 0.008) with the severity of transient psychotic symptoms induced by THC. This difference was not present when we compared two subgroups from the same sample that were defined by sensitivity to anxiogenic effects of THC. CONCLUSIONS These results suggest that altered hippocampal activation during verbal encoding may serve as a marker of sensitivity to the acute psychotomimetic effects of THC.
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Affiliation(s)
- Sagnik Bhattacharyya
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Thomas Sainsbury
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Paul Allen
- Department of Psychology,University of Roehampton,UK
| | - Chiara Nosarti
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Zerrin Atakan
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
| | - Vincent Giampietro
- Department of Neuroimaging,King's College London, Institute of Psychiatry,PO Box 089, De Crespigny Park, London, SE5 8AF,UK
| | - Michael Brammer
- Department of Neuroimaging,King's College London, Institute of Psychiatry,PO Box 089, De Crespigny Park, London, SE5 8AF,UK
| | - P K McGuire
- Department of Psychosis Studies,King's College London, Institute of Psychiatry,De Crespigny Park, London, SE5 8AF,UK
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16
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Bloomfield MAP, Hindocha C, Green SF, Wall MB, Lees R, Petrilli K, Costello H, Ogunbiyi MO, Bossong MG, Freeman TP. The neuropsychopharmacology of cannabis: A review of human imaging studies. Pharmacol Ther 2018; 195:132-161. [PMID: 30347211 PMCID: PMC6416743 DOI: 10.1016/j.pharmthera.2018.10.006] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The laws governing cannabis are evolving worldwide and associated with changing patterns of use. The main psychoactive drug in cannabis is Δ9-tetrahydrocannabinol (THC), a partial agonist at the endocannabinoid CB1 receptor. Acutely, cannabis and THC produce a range of effects on several neurocognitive and pharmacological systems. These include effects on executive, emotional, reward and memory processing via direct interactions with the endocannabinoid system and indirect effects on the glutamatergic, GABAergic and dopaminergic systems. Cannabidiol, a non-intoxicating cannabinoid found in some forms of cannabis, may offset some of these acute effects. Heavy repeated cannabis use, particularly during adolescence, has been associated with adverse effects on these systems, which increase the risk of mental illnesses including addiction and psychosis. Here, we provide a comprehensive state of the art review on the acute and chronic neuropsychopharmacology of cannabis by synthesizing the available neuroimaging research in humans. We describe the effects of drug exposure during development, implications for understanding psychosis and cannabis use disorder, and methodological considerations. Greater understanding of the precise mechanisms underlying the effects of cannabis may also give rise to new treatment targets.
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Affiliation(s)
- Michael A P Bloomfield
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Psychiatric Imaging Group, MRC London Institute of Medical Sciences, Hammersmith Hospital, London, United Kingdom; NIHR University College London Hospitals Biomedical Research Centre, University College Hospital, London, United Kingdom; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, United Kingdom.
| | - Chandni Hindocha
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; NIHR University College London Hospitals Biomedical Research Centre, University College Hospital, London, United Kingdom
| | - Sebastian F Green
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom
| | - Matthew B Wall
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Centre for Neuropsychopharmacology, Division of Brain Sciences, Faculty of Medicine, Imperial College London, United Kingdom; Invicro UK, Hammersmith Hospital, London, United Kingdom
| | - Rachel Lees
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Institute of Cognitive Neuroscience, Faculty of Brain Sciences, University College London, United Kingdom
| | - Katherine Petrilli
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Institute of Cognitive Neuroscience, Faculty of Brain Sciences, University College London, United Kingdom
| | - Harry Costello
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom
| | - M Olabisi Ogunbiyi
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom
| | - Matthijs G Bossong
- Department of Psychiatry, Brain Center Rudolf Magnus, University Medical Center Utrecht, the Netherlands
| | - Tom P Freeman
- Translational Psychiatry Research Group, Research Department of Mental Health Neuroscience, Division of Psychiatry, Faculty of Brain Sciences, University College London, United Kingdom; Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, Faculty of Brain Sciences, University College London, United Kingdom; Department of Psychology, University of Bath, United Kingdom; National Addiction Centre, Institute of Psychiatry, Psychology & Neuroscience, King's College London, United Kingdom
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17
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Modulation of acute effects of delta-9-tetrahydrocannabinol on psychotomimetic effects, cognition and brain function by previous cannabis exposure. Eur Neuropsychopharmacol 2018; 28:850-862. [PMID: 29935939 DOI: 10.1016/j.euroneuro.2018.04.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 04/24/2018] [Accepted: 04/30/2018] [Indexed: 01/31/2023]
Abstract
Cannabis use has been associated with psychosis and cognitive dysfunction. Some evidence suggests that the acute behavioral and neurocognitive effects of the main active ingredient in cannabis, (-)-trans-Δ9-tetrahydrocannabinol (∆9-THC), might be modulated by previous cannabis exposure. However, this has not been investigated either using a control group of non-users, or following abstinence in modest cannabis users, who represent the majority of recreational users. Twenty-four healthy men participated in a double-blind, randomized, placebo-controlled, repeated-measures, within-subject, ∆9-THC challenge study. Compared to non-users (N=12; <5 lifetime cannabis joints smoked), abstinent modest cannabis users (N=12; 24.5±9 lifetime cannabis joints smoked) showed worse performance and stronger right hemispheric activation during cognitive processing, independent of the acute challenge (all P≤0.047). Acute ∆9-THC administration produced transient anxiety and psychotomimetic symptoms (all P≤0.02), the latter being greater in non-users compared to users (P=0.040). Non-users under placebo (control group) activated specific brain areas to perform the tasks, while deactivating others. An opposite pattern was found under acute (∆9-THC challenge in non-users) as well as residual (cannabis users under placebo) effect of ∆9-THC. Under ∆9-THC, cannabis users showed brain activity patterns intermediate between those in non-users under placebo (control group), and non-users under ∆9-THC (acute effect) and cannabis users under placebo (residual effect). In non-users, the more severe the ∆9-THC-induced psychotomimetic symptoms and cognitive impairments, the more pronounced was the neurophysiological alteration (all P≤0.036). Previous modest cannabis use blunts the acute behavioral and neurophysiological effects of ∆9-THC, which are more marked in people who have never used cannabis.
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18
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Cohen K, Weinstein AM. Synthetic and Non-synthetic Cannabinoid Drugs and Their Adverse Effects-A Review From Public Health Prospective. Front Public Health 2018; 6:162. [PMID: 29930934 PMCID: PMC5999798 DOI: 10.3389/fpubh.2018.00162] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 05/14/2018] [Indexed: 01/01/2023] Open
Abstract
There is a growing use of novel psychoactive substances containing synthetic cannabinoids. Synthetic cannabinoid products have effects similar to those of natural cannabis, yet, these drugs are more potent and dangerous, and have been associated with dangerous adverse effects. Here, we review current literature on the epidemiology, acute, and chronic effects of synthetic and natural cannabinoid-based drugs. Synthetic drugs contain a mixture of psychoactive compounds that mostly bind cannabinoid receptors with high potency. These synthetic drugs replicate the effects of natural cannabis and Δ9-tetrahydrocannabinol but they induce more severe adverse effects including respiratory difficulties, hypertension, tachycardia, chest pain, muscle twitches, acute renal failure, anxiety, agitation, psychosis, suicidal ideation, and cognitive impairment. Chronic use of synthetic cannabinoids has been associated with serious psychiatric and medical conditions and even death. Given the growing popularity in the use of cannabinoid-based drugs and their harmful potential, there is a need for further research in this field.
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Affiliation(s)
- Koby Cohen
- Behavioral Science, Ariel University, Science Park, Ariel, Israel
| | - Aviv M Weinstein
- Behavioral Science, Ariel University, Science Park, Ariel, Israel
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19
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Cannabis and its effects on driving skills. Forensic Sci Int 2016; 268:92-102. [DOI: 10.1016/j.forsciint.2016.09.007] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 09/07/2016] [Accepted: 09/10/2016] [Indexed: 01/15/2023]
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20
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Lewis TF, Wahesh E. Perceived Norms and Marijuana Use at Historically Black Colleges and Universities. JOURNAL OF COLLEGE COUNSELING 2015. [DOI: 10.1002/jocc.12010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Todd F. Lewis
- Department of Counseling and Educational Development; University of North Carolina at Greensboro
- Now at Counselor Education Department; North Dakota State University
| | - Edward Wahesh
- Department of Counseling and Educational Development; University of North Carolina at Greensboro
- Now at Department of Education and Counseling; Villanova University
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21
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Wetherill RR, Jagannathan K, Hager N, Childress AR, Rao H, Franklin TR. Cannabis, Cigarettes, and Their Co-Occurring Use: Disentangling Differences in Gray Matter Volume. Int J Neuropsychopharmacol 2015; 18:pyv061. [PMID: 26045474 PMCID: PMC4648161 DOI: 10.1093/ijnp/pyv061] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 05/25/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Structural magnetic resonance imaging techniques are powerful tools for examining the effects of drug use on the brain. The nicotine and cannabis literature has demonstrated differences between nicotine cigarette smokers and cannabis users compared to controls in brain structure; however, less is known about the effects of co-occurring cannabis and tobacco use. METHODS We used voxel-based morphometry to examine gray matter volume differences between four groups: (1) cannabis-dependent individuals who do not smoke tobacco (Cs); (2) cannabis-dependent individuals who smoke tobacco (CTs); (3) cannabis-naïve, nicotine-dependent individuals who smoke tobacco (Ts); and (4) healthy controls (HCs). We also explored associations between gray matter volume and measures of cannabis and tobacco use. RESULTS A significant group effect was observed in the left putamen, thalamus, right precentral gyrus, and left cerebellum. Compared to HCs, the Cs, CTs, and Ts exhibited larger gray matter volumes in the left putamen. Cs also had larger gray matter volume than HCs in the right precentral gyrus. Cs and CTs exhibited smaller gray matter volume than HCs in the thalamus, and CTs and Ts had smaller left cerebellar gray matter volume than HCs. CONCLUSIONS This study extends previous research that independently examined the effects of cannabis or tobacco use on brain structure by including an examination of co-occurring cannabis and tobacco use, and provides evidence that cannabis and tobacco exposure are associated with alterations in brain regions associated with addiction.
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Affiliation(s)
- Reagan R Wetherill
- University of Pennsylvania, Department of Psychiatry, Philadelphia, PA (Drs Wetherill, Jagannathan, Childress, Rao, and Franklin, and Mr Hager).
| | - Kanchana Jagannathan
- University of Pennsylvania, Department of Psychiatry, Philadelphia, PA (Drs Wetherill, Jagannathan, Childress, Rao, and Franklin, and Mr Hager)
| | - Nathan Hager
- University of Pennsylvania, Department of Psychiatry, Philadelphia, PA (Drs Wetherill, Jagannathan, Childress, Rao, and Franklin, and Mr Hager)
| | - Anna Rose Childress
- University of Pennsylvania, Department of Psychiatry, Philadelphia, PA (Drs Wetherill, Jagannathan, Childress, Rao, and Franklin, and Mr Hager)
| | - Hengyi Rao
- University of Pennsylvania, Department of Psychiatry, Philadelphia, PA (Drs Wetherill, Jagannathan, Childress, Rao, and Franklin, and Mr Hager)
| | - Teresa R Franklin
- University of Pennsylvania, Department of Psychiatry, Philadelphia, PA (Drs Wetherill, Jagannathan, Childress, Rao, and Franklin, and Mr Hager)
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Baron EP. Comprehensive Review of Medicinal Marijuana, Cannabinoids, and Therapeutic Implications in Medicine and Headache: What a Long Strange Trip It's Been …. Headache 2015; 55:885-916. [PMID: 26015168 DOI: 10.1111/head.12570] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2015] [Indexed: 02/06/2023]
Abstract
BACKGROUND The use of cannabis, or marijuana, for medicinal purposes is deeply rooted though history, dating back to ancient times. It once held a prominent position in the history of medicine, recommended by many eminent physicians for numerous diseases, particularly headache and migraine. Through the decades, this plant has taken a fascinating journey from a legal and frequently prescribed status to illegal, driven by political and social factors rather than by science. However, with an abundance of growing support for its multitude of medicinal uses, the misguided stigma of cannabis is fading, and there has been a dramatic push for legalizing medicinal cannabis and research. Almost half of the United States has now legalized medicinal cannabis, several states have legalized recreational use, and others have legalized cannabidiol-only use, which is one of many therapeutic cannabinoids extracted from cannabis. Physicians need to be educated on the history, pharmacology, clinical indications, and proper clinical use of cannabis, as patients will inevitably inquire about it for many diseases, including chronic pain and headache disorders for which there is some intriguing supportive evidence. OBJECTIVE To review the history of medicinal cannabis use, discuss the pharmacology and physiology of the endocannabinoid system and cannabis-derived cannabinoids, perform a comprehensive literature review of the clinical uses of medicinal cannabis and cannabinoids with a focus on migraine and other headache disorders, and outline general clinical practice guidelines. CONCLUSION The literature suggests that the medicinal use of cannabis may have a therapeutic role for a multitude of diseases, particularly chronic pain disorders including headache. Supporting literature suggests a role for medicinal cannabis and cannabinoids in several types of headache disorders including migraine and cluster headache, although it is primarily limited to case based, anecdotal, or laboratory-based scientific research. Cannabis contains an extensive number of pharmacological and biochemical compounds, of which only a minority are understood, so many potential therapeutic uses likely remain undiscovered. Cannabinoids appear to modulate and interact at many pathways inherent to migraine, triptan mechanisms ofaction, and opiate pathways, suggesting potential synergistic or similar benefits. Modulation of the endocannabinoid system through agonism or antagonism of its receptors, targeting its metabolic pathways, or combining cannabinoids with other analgesics for synergistic effects, may provide the foundation for many new classes of medications. Despite the limited evidence and research suggesting a role for cannabis and cannabinoids in some headache disorders, randomized clinical trials are lacking and necessary for confirmation and further evaluation.
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Affiliation(s)
- Eric P Baron
- Department of Neurology, Headache Center, Cleveland Clinic Neurological Institute, Cleveland, OH, USA
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Wrege J, Schmidt A, Walter A, Smieskova R, Bendfeldt K, Radue EW, Lang UE, Borgwardt S. Effects of cannabis on impulsivity: a systematic review of neuroimaging findings. Curr Pharm Des 2015; 20:2126-37. [PMID: 23829358 PMCID: PMC4052819 DOI: 10.2174/13816128113199990428] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 06/10/2013] [Indexed: 01/18/2023]
Abstract
We conducted a systematic review to assess the evidence for specific effects of cannabis on impulsivity, disinhibition and motor
control. The review had a specific focus on neuroimaging findings associated with acute and chronic use of the drug and covers literature
published up until May 2012. Seventeen studies were identified, of which 13 met the inclusion criteria; three studies investigated
acute effects of cannabis (1 fMRI, 2 PET), while six studies investigated non-acute functional effects (4 fMRI, 2 PET), and four studies
investigated structural alterations. Functional imaging studies of impulsivity studies suggest that prefrontal blood flow is lower in chronic
cannabis users than in controls. Studies of acute administration of THC or marijuana report increased brain metabolism in several brain
regions during impulsivity tasks. Structural imaging studies of cannabis users found differences in reduced prefrontal volumes and white
matter integrity that might mediate the abnormal impulsivity and mood observed in marijuana users. To address the question whether impulsivity
as a trait precedes cannabis consumption or whether cannabis aggravates impulsivity and discontinuation of usage more longitudinal
study designs are warranted.
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Affiliation(s)
| | | | | | | | | | | | | | - Stefan Borgwardt
- Department of Psychiatry UPK, University of Basel, Petersgraben 4, 4031 Basel, Switzerland.
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Impairment of inhibitory control processing related to acute psychotomimetic effects of cannabis. Eur Neuropsychopharmacol 2015; 25:26-37. [PMID: 25532865 DOI: 10.1016/j.euroneuro.2014.11.018] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2014] [Revised: 11/10/2014] [Accepted: 11/24/2014] [Indexed: 11/23/2022]
Abstract
Cannabis use can induce acute psychotic symptoms and increase the risk of schizophrenia. Impairments in inhibitory control and processing are known to occur both under the influence of cannabis and in schizophrenia. Whether cannabis-induced impairment in inhibitory processing is related to the acute induction of psychotic symptoms under its influence is unclear. We investigated the effects of acute oral administration of 10mg of delta-9-tetrahydrocannabinol (delta-9-THC), the main psychoactive ingredient of cannabis, on inhibitory control and regional brain activation during inhibitory processing in humans and examined whether these effects are related to the induction of psychotic symptoms under its influence using a repeated-measures, placebo-controlled, double-blind, within-subject design. We studied thirty-six healthy, English-speaking, right-handed men with minimal previous exposure to cannabis and other illicit drugs twice using functional magnetic resonance imaging (fMRI) while they performed a response inhibition (Go/No-Go) task. Relative to placebo, delta-9-THC caused transient psychotic symptoms, anxiety, intoxication and sedation, inhibition errors and impaired inhibition efficiency. Severity of psychotic symptoms was directly correlated with inhibition error frequency and inversely with inhibition efficiency under the influence of delta-9-THC. Delta-9-THC attenuated left inferior frontal activation which was inversely correlated with the frequency of inhibition errors and severity of psychotic symptoms and positively with inhibition efficiency under its influence. These results provide experimental evidence that impairments in cognitive processes involved in the inhibitory control of thoughts and actions and inferior frontal function under the influence of cannabis may have a role in the emergence of transient psychotic symptoms under its influence.
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Bhattacharyya S, Iyegbe C, Atakan Z, Martin-Santos R, Crippa JA, Xu X, Williams S, Brammer M, Rubia K, Prata D, Collier DA, McGuire PK. Protein kinase B (AKT1) genotype mediates sensitivity to cannabis-induced impairments in psychomotor control. Psychol Med 2014; 44:3315-3328. [PMID: 25065544 DOI: 10.1017/s0033291714000920] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND What determines inter-individual variability to impairments in behavioural control that may underlie road-traffic accidents, and impulsive and violent behaviours occurring under the influence of cannabis, the most widely used illicit drug worldwide? METHOD Employing a double-blind, repeated-measures design, we investigated the genetic and neural basis of variable sensitivity to cannabis-induced behavioural dyscontrol in healthy occasional cannabis users. Acute oral challenge with placebo or Δ9-tetrahydrocannabinol (THC), the main psychoactive ingredient in cannabis, was combined with functional magnetic resonance imaging, while participants performed a response inhibition task that involved inhibiting a pre-potent motor response. They were genotyped for rs1130233 single nucleotide polymorphisms (SNPs) of the protein kinase B (AKT1) gene. RESULTS Errors of inhibition were significantly (p = 0.008) increased following administration of THC in carriers of the A allele, but not in G allele homozygotes of the AKT1 rs1130233 SNP. The A allele carriers also displayed attenuation of left inferior frontal response with THC evident in the sample as a whole, while there was a modest enhancement of inferior frontal activation in the G homozygotes. There was a direct relationship (r = -0.327, p = 0.045) between the behavioural effect of THC and its physiological effect in the inferior frontal gyrus, where AKT1 genotype modulated the effect of THC. CONCLUSIONS These results require independent replication and show that differing vulnerability to acute psychomotor impairments induced by cannabis depends on variation in a gene that influences dopamine function, and is mediated through modulation of the effect of cannabis on the inferior frontal cortex, that is rich in dopaminergic innervation and critical for psychomotor control.
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Affiliation(s)
- S Bhattacharyya
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - C Iyegbe
- Social, Genetic and Developmental Psychiatry Centre,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - Z Atakan
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - R Martin-Santos
- Pharmacology Research Unit, IMIM-Hospital del Mar and Psychiatric Department,ICN,Hospital Clinico, Barcelona,Spain
| | - J A Crippa
- Department of Neurology, Psychiatry and Medical Psychology, Faculty of Medicine of Ribeirão Preto,University of São Paulo,Brazil
| | - X Xu
- Social, Genetic and Developmental Psychiatry Centre,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - S Williams
- Department of Neuroimaging, Centre for Neuroimaging Sciences,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - M Brammer
- Department of Neuroimaging, Centre for Neuroimaging Sciences,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - K Rubia
- Department of Child and Adolescent Psychiatry,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - D Prata
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - D A Collier
- Social, Genetic and Developmental Psychiatry Centre,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
| | - P K McGuire
- Department of Psychosis Studies,King's College London,Institute of Psychiatry, De Crespigny Park, London,UK
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Crane NA, Schuster RM, Fusar-Poli P, Gonzalez R. Effects of cannabis on neurocognitive functioning: recent advances, neurodevelopmental influences, and sex differences. Neuropsychol Rev 2013; 23:117-37. [PMID: 23129391 PMCID: PMC3593817 DOI: 10.1007/s11065-012-9222-1] [Citation(s) in RCA: 210] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 10/22/2012] [Indexed: 12/19/2022]
Abstract
Decades of research have examined the effects of cannabis on neurocognition. Recent advances in this field provide us with a better understanding of how cannabis use influences neurocognition both acutely (during intoxication) and non-acutely (after acute effects subside). Evidence of problems with episodic memory is one of the most consistent findings reported; however, several other neurocognitive domains appear to be adversely affected by cannabis use under various conditions. There is significant variability in findings across studies, thus a discussion of potential moderators is increasingly relevant. The purpose of this review was to 1) provide an update on research of cannabis' acute and non-acute effects on neurocognition, with a focus on findings since 2007 and 2) suggest and discuss how neurodevelopmental issues and sex differences may influence cannabis effects on neurocognition. Finally we discuss how future investigations may lead to better understanding of the complex interplay among cannabis, stages of neurodevelopment, and sex on neurocognitive functioning.
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Affiliation(s)
| | | | - Paolo Fusar-Poli
- Department of Psychosis Studies, Institute of Psychiatry, King’s College London
| | - Raul Gonzalez
- Department of Psychology, Florida International University
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Batalla A, Bhattacharyya S, Yücel M, Fusar-Poli P, Crippa JA, Nogué S, Torrens M, Pujol J, Farré M, Martin-Santos R. Structural and functional imaging studies in chronic cannabis users: a systematic review of adolescent and adult findings. PLoS One 2013; 8:e55821. [PMID: 23390554 PMCID: PMC3563634 DOI: 10.1371/journal.pone.0055821] [Citation(s) in RCA: 267] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 01/02/2013] [Indexed: 12/18/2022] Open
Abstract
Background The growing concern about cannabis use, the most commonly used illicit drug worldwide, has led to a significant increase in the number of human studies using neuroimaging techniques to determine the effect of cannabis on brain structure and function. We conducted a systematic review to assess the evidence of the impact of chronic cannabis use on brain structure and function in adults and adolescents. Methods Papers published until August 2012 were included from EMBASE, Medline, PubMed and LILACS databases following a comprehensive search strategy and pre-determined set of criteria for article selection. Only neuroimaging studies involving chronic cannabis users with a matched control group were considered. Results One hundred and forty-two studies were identified, of which 43 met the established criteria. Eight studies were in adolescent population. Neuroimaging studies provide evidence of morphological brain alterations in both population groups, particularly in the medial temporal and frontal cortices, as well as the cerebellum. These effects may be related to the amount of cannabis exposure. Functional neuroimaging studies suggest different patterns of resting global and brain activity during the performance of several cognitive tasks both in adolescents and adults, which may indicate compensatory effects in response to chronic cannabis exposure. Limitations However, the results pointed out methodological limitations of the work conducted to date and considerable heterogeneity in the findings. Conclusion Chronic cannabis use may alter brain structure and function in adult and adolescent population. Further studies should consider the use of convergent methodology, prospective large samples involving adolescent to adulthood subjects, and data-sharing initiatives.
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Affiliation(s)
- Albert Batalla
- Psychiatry, Institute of Neurosciences, Hospital Clínic, IDIBAPS, CIBERSAM, Barcelona, Spain
- Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain
- Melbourne Neuropsychiatry Centre, The University of Melbourne, Melbourne, Victoria, Australia
| | - Sagnik Bhattacharyya
- Department of Psychosis Studies, King’s College London, Institute of Psychiatry, London, United Kingdom
| | - Murat Yücel
- Melbourne Neuropsychiatry Centre, The University of Melbourne, Melbourne, Victoria, Australia
| | - Paolo Fusar-Poli
- Department of Psychosis Studies, King’s College London, Institute of Psychiatry, London, United Kingdom
| | - Jose Alexandre Crippa
- Neuroscience and Cognitive Behavior Department, University of Sao Paulo, Ribeirao Preto, Brazil
- National Science and Technology Institute for Translational Medicine (INCT-TM, CNPq), Ribeirao Preto, Brazil
| | - Santiago Nogué
- Clinical Toxicology Unit, Emergency Department, Hospital Clínic, IDIBAPS, University of Barcelona, Barcelona, Spain
| | - Marta Torrens
- Neuroscience Program, Pharmacology Unit and Drug Addiction Unit, IMIM-INAD-Parc de Salut Mar, Autonomous University of Barcelona, Barcelona, Spain
- Red de Trastornos Adictivos (RETIC), IMIM-INAD-Parc de Salut Mar, Barcelona, Spain
| | - Jesús Pujol
- Institut d’Alta Tecnologia-PRBB, CRC Mar, Hospital del Mar, Barcelona, Spain
| | - Magí Farré
- Neuroscience Program, Pharmacology Unit and Drug Addiction Unit, IMIM-INAD-Parc de Salut Mar, Autonomous University of Barcelona, Barcelona, Spain
- Red de Trastornos Adictivos (RETIC), IMIM-INAD-Parc de Salut Mar, Barcelona, Spain
| | - Rocio Martin-Santos
- Psychiatry, Institute of Neurosciences, Hospital Clínic, IDIBAPS, CIBERSAM, Barcelona, Spain
- Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain
- National Science and Technology Institute for Translational Medicine (INCT-TM, CNPq), Ribeirao Preto, Brazil
- * E-mail:
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Harding IH, Solowij N, Harrison BJ, Takagi M, Lorenzetti V, Lubman DI, Seal ML, Pantelis C, Yücel M. Functional connectivity in brain networks underlying cognitive control in chronic cannabis users. Neuropsychopharmacology 2012; 37:1923-33. [PMID: 22534625 PMCID: PMC3376324 DOI: 10.1038/npp.2012.39] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The long-term effect of regular cannabis use on brain function underlying cognitive control remains equivocal. Cognitive control abilities are thought to have a major role in everyday functioning, and their dysfunction has been implicated in the maintenance of maladaptive drug-taking patterns. In this study, the Multi-Source Interference Task was employed alongside functional magnetic resonance imaging and psychophysiological interaction methods to investigate functional interactions between brain regions underlying cognitive control. Current cannabis users with a history of greater than 10 years of daily or near-daily cannabis smoking (n=21) were compared with age, gender, and IQ-matched non-using controls (n=21). No differences in behavioral performance or magnitude of task-related brain activations were evident between the groups. However, greater connectivity between the prefrontal cortex and the occipitoparietal cortex was evident in cannabis users, as compared with controls, as cognitive control demands increased. The magnitude of this connectivity was positively associated with age of onset and lifetime exposure to cannabis. These findings suggest that brain regions responsible for coordinating behavioral control have an increased influence on the direction and switching of attention in cannabis users, and that these changes may have a compensatory role in mitigating cannabis-related impairments in cognitive control or perceptual processes.
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Affiliation(s)
- Ian H Harding
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, VIC, Australia.
| | - Nadia Solowij
- School of Psychology, University of Wollongong, Wollongong, NSW, Australia,Schizophrenia Research Institute, Sydney, NSW, Australia
| | - Ben J Harrison
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, VIC, Australia
| | - Michael Takagi
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, VIC, Australia
| | - Valentina Lorenzetti
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, VIC, Australia
| | - Dan I Lubman
- Turning Point Alcohol and Drug Centre, Eastern Health and Monash University, Melbourne, VIC, Australia
| | - Marc L Seal
- Murdoch Childrens Research Institute, Melbourne, VIC, Australia,Department of Paediatrics, University of Melbourne, Melbourne, VIC, Australia
| | - Christos Pantelis
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, VIC, Australia
| | - Murat Yücel
- Department of Psychiatry, Melbourne Neuropsychiatry Centre, University of Melbourne and Melbourne Health, Melbourne, VIC, Australia,Department of Psychiatry, Melbourne Neuropsychiatry Centre, Alan Gilbert Building, University of Melbourne, 3/161 Barry Street, Carlton, Melbourne, VIC 3053, Australia, Tel: (+61 3) 8344 1861, Fax: (+61 3) 9348 0469, E-mail: and
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Cortico-cerebellar abnormalities in adolescents with heavy marijuana use. Psychiatry Res 2012; 202:224-32. [PMID: 22835865 PMCID: PMC3423594 DOI: 10.1016/j.pscychresns.2011.11.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Revised: 11/09/2011] [Accepted: 11/10/2011] [Indexed: 12/30/2022]
Abstract
There are currently no studies that have evaluated the motor network, including the cerebellum, in adolescent marijuana (MJ) smokers. The current study aimed to evaluate whether there were activation differences in Brodmann's area 4 (BA4), Brodmann's area 6 (BA6), cingulate (CG) and cerebellum between MJ-using adolescents and healthy controls (HC) on a functional magnetic resonance imaging (fMRI) bilateral finger-tapping task. Twenty-four adolescents (aged 18.2 ± 0.7 years) with heavy MJ use and 24 HC (18.0 ± 1.9) had MRI scans on a 3T Siemens scanner, including a standard bilateral fMRI finger-tapping sequence. Imaging data were analyzed using SPM5 in Matlab. As regions of interest, BA4, BA6, cingulate (CG) and cerebellum were selected, and significant clusters of activity were thresholded at p<0.05, corrected. Healthy controls had significantly greater activation than MJ users for the CG and cerebellum. In addition, activation of the cerebellum and CG correlated with lifetime MJ smokes. This is one of the first studies to evaluate cortico-cerebellar circuits in adolescents with heavy MJ use. The study, which used a bilateral finger-tapping fMRI task, provides evidence for both CG and cerebellar dysfunction in MJ abuse and indicates that lifetime MJ use may impact the developing brain.
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Dow-Edwards D, Izenwasser S. Pretreatment with Δ9-tetrahydrocannabinol (THC) increases cocaine-stimulated activity in adolescent but not adult male rats. Pharmacol Biochem Behav 2011; 100:587-91. [PMID: 21951601 DOI: 10.1016/j.pbb.2011.09.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 09/07/2011] [Accepted: 09/14/2011] [Indexed: 10/17/2022]
Abstract
Marijuana (Cannabis sativa) remains one of the most widely used illegal drugs, with adolescents being particularly vulnerable to its use and abuse. In spite of this, most studies are conducted in adult animals even though the effects might be quite different in adolescents. Additionally, the use of marijuana often precedes the use of other psychoactive drugs including cocaine, especially when marijuana exposure begins during early adolescence. The purpose of this study was to examine the effects of repeated Δ9-tetrahydrocannabinol (THC), the major active ingredient in marijuana, in adolescents compared to adults and to determine its subsequent effects on cocaine-stimulated activity. To this end, adolescent (postnatal day PND 34) and adult (PND 66) rats were administered 3 mg/kg/day THC for 8 days and locomotor activity was measured on days 1, 2, 7 and 8 after dosing. On day 12 (4 days after the last dose of THC), rats were injected with escalating doses of cocaine and behavior was recorded. Results show that THC depressed locomotor activity in adult rats but not in adolescents. However, following a cocaine challenge, adolescents exposed to THC showed increased locomotor responses to cocaine compared to chronic vehicle-injected controls. This was not seen in adults. These results show that the effects of cocaine are enhanced after THC in adolescents, but not adults, and that this might account for the greater transition to cocaine after early, as opposed to later, marijuana use.
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Affiliation(s)
- Diana Dow-Edwards
- Department of Physiology and Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA
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Dumont GJH, van Hasselt JGC, de Kam M, van Gerven JMA, Touw DJ, Buitelaar JK, Verkes RJ. Acute psychomotor, memory and subjective effects of MDMA and THC co-administration over time in healthy volunteers. J Psychopharmacol 2011; 25:478-89. [PMID: 20817749 DOI: 10.1177/0269881110376687] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In Western societies a considerable percentage of young people expose themselves to the combination of 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy') and cannabis. The aim of the present study was to assess the acute effects of co-administration of MDMA and THC (the main psychoactive compound of cannabis) on pharmacokinetics, psychomotor performance, memory and subjective experience over time. We performed a four-way, double blind, randomized, crossover, placebo-controlled study in 16 healthy volunteers (12 male, four female) between the ages of 18 and 27. MDMA (100 mg) was given orally, THC (4, 6, and 6 mg, interval of 90 min) was vaporized and inhaled. THC induced more robust cognitive impairment compared with MDMA, and co-administration did not exacerbate single drug effects on cognitive function. However, co-administration of THC with MDMA increased desired subjective drug effects and drug strength compared with the MDMA condition, which may explain the widespread use of this combination.
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Affiliation(s)
- G J H Dumont
- Donders Institute for Brain, Cognition and Behaviour, Department of Psychiatry, Radboud University Nijmegen Medical Centre, The Netherlands.
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Ronen A, Chassidim HS, Gershon P, Parmet Y, Rabinovich A, Bar-Hamburger R, Cassuto Y, Shinar D. The effect of alcohol, THC and their combination on perceived effects, willingness to drive and performance of driving and non-driving tasks. ACCIDENT; ANALYSIS AND PREVENTION 2010; 42:1855-1865. [PMID: 20728636 DOI: 10.1016/j.aap.2010.05.006] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 05/01/2010] [Accepted: 05/10/2010] [Indexed: 05/29/2023]
Abstract
BACKGROUND Driving under the influence of drugs (DUID) is one of the main causes of car accidents. Alcohol and marijuana are the most popular drugs among recreational users. Many classify these drugs as "Light" drugs and therefore allow themselves to drive after consuming them. OBJECTIVE The study had two main objectives: 1) to investigate the effect of alcohol (BAC=0.05%), THC (13 mg) and their combination on driving and non-driving tasks. 2) to investigate the extent to which people are willing to drive based on their subjective sensations and their perceived effects of the drugs. METHOD 7 healthy men and 5 healthy women, ages 24-29, all recreational users of alcohol and marijuana, completed 5 experimental sessions. Sessions included: drinking and smoking placebo, drinking alcohol and smoking placebo, drinking placebo and smoking THC, drinking alcohol and smoking THC, drinking placebo and smoking placebo 24 hours after drinking alcohol and smoking THC. Three types of measures were used: subjective perceptions (with questionnaires), performance parameters of the driving and non-driving tasks (arithmetic task and a secondary target detection task) and physiological changes (heart rate). RESULTS Overall, the combination of alcohol and THC had the most intense effect after intake. This effect was reflected in performance impairments observed in the driving and non-driving tasks, in the subjective sensations after intake, and in the physiological measures. Despite significant differences in the size of the effects after the various treatments, there were no differences in the distances subjects were willing to drive while under the influence on each of the treatments.
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Affiliation(s)
- Adi Ronen
- Ben-Gurion University of the Negev, Beer Sheva, Israel.
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Harte LC, Dow-Edwards D. Sexually dimorphic alterations in locomotion and reversal learning after adolescent tetrahydrocannabinol exposure in the rat. Neurotoxicol Teratol 2010; 32:515-24. [PMID: 20460150 DOI: 10.1016/j.ntt.2010.05.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 04/20/2010] [Accepted: 05/03/2010] [Indexed: 10/19/2022]
Abstract
Research suggests that use and abuse of marijuana can be especially harmful if it occurs during adolescence, a period of vast developmental changes throughout the brain. We examined the effects of 2mg/kg (9)-tetrahydrocannabinol (THC) administered daily via intra-peritoneal injections during juvenile/early adolescence (postnatal day 22-40) or late adolescence (postnatal day 41-60) on locomotor activity, development of tolerance, and acquisition/retention of spatial avoidance in adulthood. THC caused locomotor depression in both male and female animals dosed during early adolescence but only in female animals dosed during late adolescence. Evidence of reverse tolerance to THC was seen in early adolescent animals only. In the active place avoidance test (APA), male and female animals administered THC during early adolescence made more errors on the reversal trial requiring flexibility in learning, but in animals dosed during late adolescence there were no significant sex or treatment differences. The results of the locomotor activity study indicate that females may be more sensitive to the effects of THC than males, while results of both locomotor activity and APA studies suggest that early adolescents appear to be more vulnerable to these effects than late adolescents/young adults.
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Affiliation(s)
- Lauren C Harte
- Department of Physiology/Pharmacology, Program in Neural and Behavioral Sciences, State University of New York Downstate Medical Center, 450 Clarkson Avenue, Brooklyn, NY 11203, USA
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Martín-Santos R, Fagundo AB, Crippa JA, Atakan Z, Bhattacharyya S, Allen P, Fusar-Poli P, Borgwardt S, Seal M, Busatto GF, McGuire P. Neuroimaging in cannabis use: a systematic review of the literature. Psychol Med 2010; 40:383-398. [PMID: 19627647 DOI: 10.1017/s0033291709990729] [Citation(s) in RCA: 160] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND We conducted a systematic review to assess the evidence for specific effects of cannabis on brain structure and function. The review focuses on the cognitive changes associated with acute and chronic use of the drug. METHOD We reviewed literature reporting neuroimaging studies of chronic or acute cannabis use published up until January 2009. The search was conducted using Medline, EMBASE, LILACS and PsycLIT indexing services using the following key words: cannabis, marijuana, delta-9-tetrahydrocannabinol, THC, cannabidiol, CBD, neuroimaging, brain imaging, computerized tomography, CT, magnetic resonance, MRI, single photon emission tomography, SPECT, functional magnetic resonance, fMRI, positron emission tomography, PET, diffusion tensor MRI, DTI-MRI, MRS and spectroscopy. RESULTS Sixty-six studies were identified, of which 41 met the inclusion criteria. Thirty-three were functional (SPECT/PET/fMRI) and eight structural (volumetric/DTI) imaging studies. The high degree of heterogeneity across studies precluded a meta-analysis. The functional studies suggest that resting global and prefrontal blood flow are lower in cannabis users than in controls. The results from the activation studies using a cognitive task are inconsistent because of the heterogeneity of the methods used. Studies of acute administration of THC or marijuana report increased resting activity and activation of the frontal and anterior cingulate cortex during cognitive tasks. Only three of the structural imaging studies found differences between users and controls. CONCLUSIONS Functional neuroimaging studies suggest a modulation of global and prefrontal metabolism both during the resting state and after the administration of THC/marijuana cigarettes. Minimal evidence of major effects of cannabis on brain structure has been reported.
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Affiliation(s)
- R Martín-Santos
- Section of Neuroimaging, PO67 Division of Psychological Medicine, Institute of Psychiatry, King's College London, UK.
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Morera-Herreras T, Ruiz-Ortega JA, Ugedo L. Two opposite effects of Δ9-tetrahydrocannabinol on subthalamic nucleus neuron activity: Involvement of GABAergic and glutamatergic neurotransmission. Synapse 2010; 64:20-9. [DOI: 10.1002/syn.20701] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Koethe D, Hoyer C, Leweke FM. The endocannabinoid system as a target for modelling psychosis. Psychopharmacology (Berl) 2009; 206:551-61. [PMID: 19529920 DOI: 10.1007/s00213-009-1591-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2009] [Accepted: 06/05/2009] [Indexed: 10/20/2022]
Abstract
INTRODUCTION Model psychosis is characterised by experimentally induced symptoms of withdrawal from reality, frequently accompanied by perceptual disturbances, thought disorders, delusional ideas and sometimes by hallucinations. These "altered states of consciousness" provide a long-standing and valid approach to enhance our understanding of certain aspects of schizophrenia. DISCUSSION Targeting the endocannabinoid system to investigate its involvement in the pathophysiology of schizophrenia became increasingly relevant with the discovery of this system and amounting epidemiological evidence for a deleterious influence of cannabis use on both manifestation and course of the disease. The majority of studies in the field are targeted to investigate drug effect of cannabis and cannabinoids not immediately related to psychosis. CONCLUSION In this review, we summarise studies relevant for or designed as model psychosis experiments. Based on the data available, we examine the contribution of these studies to an improved neurobiological assessment of endocannabinoid functioning in psychosis and schizophrenia. An outline for future studies in the field and cross-links to other approaches to model psychosis is provided.
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Affiliation(s)
- Dagmar Koethe
- Central Institute of Mental Health, Ruprecht-Karls-University Heidelberg, Mannheim, Germany
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