ArticleFrontiers in pharmacology2021
The Effects of Repeated Morphine Treatment on the Endogenous Cannabinoid System in the Ventral Tegmental Area.
Article in Frontiers in pharmacology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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Who cites it
18 citing papers in PubMed, 23 citations in OpenAlex.
- Cannabinoid-based Pharmacology for the Management of Substance Use Disorders.Current topics in behavioral neurosciences · 2026Review
- FAAH and MAGL inhibition: Evolving approaches to treating substance use disorders.Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics · 2026Review
- Does cannabis use substitute for opioids? A preliminary exploratory survey in opioid maintenance patients.European archives of psychiatry and clinical neuroscience · 2025Article
- The Effect of Antinociceptive Dose of Morphine on Cell Therapy in Rats with Spinal Cord Injury.Molecular neurobiology · 2025Article
- Fentanyl exposure alters rat CB1 receptor expression in the insula, nucleus accumbens and substantia nigra.Neuroscience letters · 2025Article
- The effect of cannabinoid type Ⅱ receptor on the excitability of substantia nigra dopaminergic neurons.Frontiers in pharmacology · 2025Article
- Elevating levels of the endocannabinoid 2-arachidonoylglycerol blunts opioid reward but not analgesia.Science advances · 2024Article
- AM6527, a neutral CB1 receptor antagonist, suppresses opioid taking and seeking, as well as cocaine seeking in rodents without aversive effects.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2024Article
- Endocannabinoids and related lipids linked to social exclusion in individuals with chronic non-medical prescription opioid use.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2024Article
- Selective Elimination of Senescent Cancer Cells by Galacto-Modified PROTACs.Journal of medicinal chemistry · 2024Article
- Elevating levels of the endocannabinoid 2-arachidonoylglycerol blunts opioid reward but not analgesia.bioRxiv : the preprint server for biology · 2024Article
- Dysregulation of the endogenous cannabinoid system following opioid exposure.Psychiatry research · 2023Review
- Article
- Review
- Targeting 5-HTNeuroscience letters · 2022Article
- Brain Penetrant, but not Peripherally Restricted, Synthetic Cannabinoid 1 Receptor Agonists Promote Morphine-Mediated Respiratory Depression.Cannabis and cannabinoid research · 2022Article
- Repeated cocaine administration upregulates CBActa pharmacologica Sinica · 2022Article
- Biomarkers of the Endocannabinoid System in Substance Use Disorders.Biomolecules · 2022Review
Corrections and comments
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Authors and funding
9 authors at 1 institution in 1 country.
Funding
Abstract
The therapeutic utility of opioids is diminished by their ability to induce rewarding behaviors that may lead to opioid use disorder. Recently, the endogenous cannabinoid system has emerged as a hot topic in the study of opioid reward but relatively little is known about how repeated opioid exposure may affect the endogenous cannabinoid system in the mesolimbic reward circuitry. In the present study, we investigated how sustained morphine may modulate the endogenous cannabinoid system in the ventral tegmental area (VTA) of Sprague Dawley rats, a critical region in the mesolimbic reward circuitry. Studies here using proteomic analysis and quantitative real-time PCR (qRT-PCR) found that the VTA expresses 32 different proteins or genes related to the endogenous cannabinoid system; three of these proteins or genes (PLCγ2, ABHD6, and CB2R) were significantly affected after repeated morphine exposure (CB2R was only detected by qRT-PCR but not proteomics). We also identified that repeated morphine treatment does not alter either anandamide (AEA) or 2-arachidonoylglycerol (2-AG) levels in the VTA compared to saline treatment; however, there may be diminished levels of anandamide (AEA) production in the VTA 4 h after a single morphine injection in both chronic saline and morphine pretreated cohorts. Treating the animals with an inhibitor of 2-AG degradation significantly decreased repeated opioid rewarding behavior. Taken together, our studies reveal a potential influence of sustained opioids on the endocannabinoid system in the VTA, suggesting that the endogenous cannabinoid system may participate in the opioid-induced reward.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.