ArticleMolecular pain2006
The mu opioid agonist morphine modulates potentiation of capsaicin-evoked TRPV1 responses through a cyclic AMP-dependent protein kinase A pathway.
Article in Molecular pain, 2006. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 42 papers.
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Who cites it
42 citing papers in PubMed, 109 citations in OpenAlex.
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- Physiological functions and pharmacological targeting of transient receptor potential channels.Pharmacological reviews · 2025Review
- Inhibition of Dorsal Root Ganglia Transient Receptor Potential Ankyrin 1 Upregulation Contributes to the Protective Effect of Morphine Against Gastric Mucosal Damage Induced by Water-Immersion Restraint Stress.The Turkish journal of gastroenterology : the official journal of Turkish Society of Gastroenterology · 2024Article
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- The dual role of TRPV1 in peripheral neuropathic pain: pain switches caused by its sensitization or desensitization.Frontiers in molecular neuroscience · 2024Review
- The role of adenosine receptor ligands on inflammatory pain: possible modulation of TRPV1 receptor function.Inflammopharmacology · 2023Article
- Optimized flow cytometric detection of transient receptor potential vanilloid-1 (TRPV1) in human hematological malignancies.Medical oncology (Northwood, London, England) · 2022Article
- Targeted esterase-induced dye (TED) loading supports direct calcium imaging in eukaryotic cell-free systems.RSC advances · 2021Article
- TRPV1 in Pain and Itch.Advances in experimental medicine and biology · 2021Article
- The nonselective cation channel TRPV4 inhibits angiotensin II receptors.The Journal of biological chemistry · 2020Article
- β-Arrestin 2 and ERK1/2 Are Important Mediators Engaged in Close Cooperation between TRPV1 and µ-Opioid Receptors in the Plasma Membrane.International journal of molecular sciences · 2020Article
- Addition of K22 Converts Spider Venom Peptide Pme2a from an Activator to an Inhibitor of NaBiomedicines · 2020Article
- Methanol Extract ofBiomolecules · 2020Article
- Opioid Receptors in Immune and Glial Cells-Implications for Pain Control.Frontiers in immunology · 2020Review
- Nociceptor Signalling through ion Channel Regulation via GPCRs.International journal of molecular sciences · 2019Review
- MBD1 Contributes to the Genesis of Acute Pain and Neuropathic Pain by Epigenetic Silencing ofThe Journal of neuroscience : the official journal of the Society for Neuroscience · 2018Article
- Endogenous and Exogenous Opioids in Pain.Annual review of neuroscience · 2018Review
- Advances in Achieving Opioid Analgesia Without Side Effects.Frontiers in pharmacology · 2018Review
Corrections and comments
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Authors and funding
5 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe vanilloid receptor 1 (TRPV1) is critical in the development of inflammatory hyperalgesia. Several receptors including G-protein coupled prostaglandin receptors have been reported to functionally interact with the TRPV1 through a cAMP-dependent protein kinase A (PKA) pathway to potentiate TRPV1-mediated capsaicin responses. Such regulation may have significance in inflammatory pain. However, few functional receptor interactions that inhibit PKA-mediated potentiation of TRPV1 responses have been described.
resultsIn the present studies we investigated the hypothesis that the mu opioid receptor (MOP) agonist morphine can modulate forskolin-potentiated capsaicin responses through a cAMP-dependent PKA pathway. HEK293 cells were stably transfected with TRPV1 and MOP, and calcium (Ca2+) responses to injection of the TRPV1 agonist capsaicin were monitored in Fluo-3-loaded cells. Pre-treatment with morphine did not inhibit unpotentiated capsaicin-induced Ca2+ responses but significantly altered capsaicin responses potentiated by forskolin. TRPV1-mediated Ca2+ responses potentiated by the direct PKA activator 8-Br-cAMP and the PKC activator Phorbol-12-myristate-13-acetatewere not modulated by morphine. Immunohistochemical studies confirmed that the TRPV1 and MOP are co-expressed on cultured Dorsal Root Ganglion neurones, pointing towards the existence of a functional relationship between the G-protein coupled MOP and nociceptive TRPV1.
conclusionThe results presented here indicate that the opioid receptor agonist morphine acts via inhibition of adenylate cyclase to inhibit PKA-potentiated TRPV1 responses. Targeting of peripheral opioid receptors may therefore have therapeutic potential as an intervention to prevent potentiation of TRPV1 responses through the PKA pathway in inflammation.
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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.