ArticleBritish journal of pharmacology2005
Opioid tolerance in periaqueductal gray neurons isolated from mice chronically treated with morphine.
Article in British journal of pharmacology, 2005. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 52 papers.
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Who cites it
52 citing papers in PubMed, 81 citations in OpenAlex.
- Trial
- Decoding the role of mNeurochemistry international · 2025Review
- A Balancing Act: Learning from the Past to Build a Future-Focused Opioid Strategy.Annual review of physiology · 2024Review
- Chronic Morphine Induces Adaptations in Opioid Receptor Signaling in a Thalamostriatal Circuit That Are Location Dependent, Sex Specific, and Regulated by μ-Opioid Receptor Phosphorylation.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2024Article
- Article
- Opioid withdrawal: role in addiction and neural mechanisms.Psychopharmacology · 2023Review
- Key differences in regulation of opioid receptors localized to presynaptic terminals compared to somas: Relevance for novel therapeutics.Neuropharmacology · 2023Review
- Chronic morphine induces adaptations in opioid receptor signaling in a thalamo-cortico-striatal circuit that are projection-dependent, sex-specific and regulated by mu opioid receptor phosphorylation.bioRxiv : the preprint server for biology · 2023Article
- A Regional and Projection-Specific Role of RGSz1 in the Ventrolateral Periaqueductal Grey in the Modulation of Morphine Reward.Molecular pharmacology · 2023Article
- Anterior cingulate cortex is necessary for spontaneous opioid withdrawal and withdrawal-induced hyperalgesia in male mice.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2021Article
- Synthesis of the Mechanisms of Opioid Tolerance: Do We Still Say NO?Cellular and molecular neurobiology · 2021Review
- Identifying the Neurodevelopmental Differences of Opioid Withdrawal.Cellular and molecular neurobiology · 2021Article
- Effect of heat shock protein 70 modulators on the development of morphine analgesic tolerance in rats.Behavioural pharmacology · 2020Article
- Phosphorylation of unique C-terminal sites of the mu-opioid receptor variants 1B2 and 1C1 influences their Gs association following chronic morphine.Journal of neurochemistry · 2020Article
- Spinal TLR4/P2X7 Receptor-Dependent NLRP3 Inflammasome Activation Contributes to the Development of Tolerance to Morphine-Induced Antinociception.Journal of inflammation research · 2020Article
- Inflammatory mediators of opioid tolerance: Implications for dependency and addiction.Peptides · 2019Review
- Neuronal and glial factors contributing to sex differences in opioid modulation of pain.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2019Review
- Review
- Suppression of RGSz1 function optimizes the actions of opioid analgesics by mechanisms that involve the Wnt/β-catenin pathway.Proceedings of the National Academy of Sciences of the United States of America · 2018Article
- The Contribution of the Descending Pain Modulatory Pathway in Opioid Tolerance.Frontiers in neuroscience · 2018Article
Corrections and comments
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Authors and funding
4 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The midbrain periaqueductal gray (PAG) is a major site of opioid analgesic action, and a significant site of cellular adaptations to chronic morphine treatment (CMT). We examined mu-opioid receptor (MOP) regulation of voltage-gated calcium channel currents (I(Ca)) and G-protein-activated K channel currents (GIRK) in PAG neurons from CMT mice. Mice were injected s.c. with 300 mg kg(-1) of morphine base in a slow release emulsion three times over 5 days, or with emulsion alone (vehicles). This protocol produced significant tolerance to the antinociceptive effects of morphine in a test of thermal nociception. Voltage clamp recordings were made of I(Ca) in acutely isolated PAG neurons and GIRK in PAG slices. The MOP agonist DAMGO (Tyr-D-Ala-Gly-N-Me-Phe-Gly-ol enkephalin) inhibited I(Ca) in neurons from CMT mice (230 nM) with a similar potency to vehicle (150 nM), but with a reduced maximal effectiveness (37% inhibition in vehicle neurons, 27% in CMT neurons). Inhibition of I(Ca) by the GABA(B) agonist baclofen was not altered by CMT. Met-enkephalin-activated GIRK currents recorded in PAG slices were significantly smaller in neurons from CMT mice than vehicles, while GIRK currents activated by baclofen were unaltered. These data demonstrate that CMT-induced antinociceptive tolerance is accompanied by homologous reduction in the effectiveness of MOP agonists to inhibit I(Ca) and activate GIRK. Thus, a reduction in MOP number and/or functional coupling to G proteins accompanies the characteristic cellular adaptations to CMT previously described in PAG neurons.
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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.