ArticleJournal of anesthesia2015
µ-Opioid receptor activation by tramadol and O-desmethyltramadol (M1).
Article in Journal of anesthesia, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 15 papers.
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Who cites it
15 citing papers in PubMed, 27 citations in OpenAlex.
- Tramadol-Induced Persistent Singultus: A Case Report on Diagnosis, Mechanism, and Management.Clinical case reports · 2026Article
- Tramadol for treatment of neurogenic cough: a retrospective case series.The Journal of laryngology and otology · 2026Article
- Article
- Pediatric Palliative Care Pharmacy Pearls-A Focus on Pain and Sedation.Children (Basel, Switzerland) · 2021Article
- Autopsy case of fatal hypoglycemia following ingestion of a therapeutic dose of tramadol.Forensic science, medicine, and pathology · 2021Article
- Tramadol Treatment Induces Change in Phospho-Cyclic Adenosine Monophosphate Response Element-Binding Protein and Delta and Mu Opioid Receptors within Hippocampus and Amygdala Areas of Rat Brain.Addiction & health · 2021Article
- Ketamine Versus Tramadol As an Adjunct To PCA Morphine for Postoperative Analgesia After Major Upper Abdominal Surgery: a Prospective, Comparative, Randomized Trial.Romanian journal of anaesthesia and intensive care · 2020Article
- Chronic use of tramadol after acute pain episode: cohort study.BMJ (Clinical research ed.) · 2019Observational
- Essential pharmacologic options for acute pain management in the emergency setting.Turkish journal of emergency medicine · 2019Review
- A "novel" association to treat pain: tramadol/dexketoprofen. The first drug of a "new pharmacological class".Acta bio-medica : Atenei Parmensis · 2017Article
- Pharmacokinetics and Pharmacodynamics Evaluation of Tramadol in Thermoreversible Gels.BioMed research international · 2017Article
- Hypoglycemic effects of tramadol analgesia in hospitalized patients: a case-control study.Journal of diabetes and metabolic disorders · 2017Article
- What is the main mechanism of tramadol?Naunyn-Schmiedeberg's archives of pharmacology · 2015Review
- Acute Tramadol-Induced Cellular Tolerance and Dependence of Ventral Tegmental Area Dopaminergic Neurons: An In Vivo Electrophysiological Study.Basic and clinical neuroscienceArticle
- Inhibition by O-desmethyltramadol of glutamatergic excitatory transmission in adult rat spinal substantia gelatinosa neurons.Molecular painArticle
Corrections and comments
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Authors and funding
5 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Tramadol has been used as an analgesic for several decades. µ-Opioid receptors (µORs) are the major receptors that mediate the analgesic effects of opioids. Although µORs have been thought to be one of the sites of action of tramadol, there has been no report that directly proves whether tramadol is an agonist of μOR or not. In this study, we examined the effects of tramadol and its main active metabolite O-desmethyltramadol (M1), on the function of µORs using Xenopus oocytes expressing cloned human µORs. The effects of tramadol and M1 were evaluated using the Ca(2+)-activated Cl(-) current assay method for G(i/o)-protein-coupled receptors by using a µOR fused to G(qi5) (µOR-G(qi5)) in Xenopus oocytes. DAMGO [(D-Ala(2), N-MePhe(4), Gly(5)-ol)-enkephalin] evoked Cl(-) currents in oocytes expressing µOR-G(qi5) in a concentration-dependent manner. Tramadol and M1 also evoked Cl(-) currents in the oocytes expressing µOR-G(qi5); however, relatively higher concentrations (compared to DMAGO) were necessary to induce such currents. Tramadol and M1 had a direct effect on µORs expressed in Xenopus oocytes. Although the monoamine uptake system and several types of ligand-gated ion channels are thought to be one of the targets for tramadol, tramadol-induced antinociception may be mediated at least in part, by the direct activation of µORs.
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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.