ArticleThe international journal of neuropsychopharmacology2019
Serotonin and Norepinephrine Transporter Occupancy of Tramadol in Nonhuman Primate Using Positron Emission Tomography.
Article in The international journal of neuropsychopharmacology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 3 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
3 citing papers in PubMed, 5 citations in OpenAlex.
- Tramadol for Refractory Restless Legs Syndrome Following Methadone Intolerance: A Case Report.Cureus · 2026Article
- Innovative Approaches to Depression Therapy: The Antidepressant Efficacy and Mechanisms of General Anesthetics.Current neuropharmacology · 2026Review
- Recent advances in radiotracers targeting norepinephrine transporter: structural development and radiolabeling improvements.Journal of neural transmission (Vienna, Austria : 1996) · 2020Review
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Authors and funding
3 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Background: Tramadol, a centrally acting analgesic drug, has relatively high affinity to serotonin transporter and norepinephrine transporter in addition to μ-opioid receptor. Based on this characteristic, tramadol is expected to have an antidepressant effect. Methods: Positron emission tomography measurements with [11C]MADAM and [18F]FMeNER-D2 were performed at baseline and after i.v. administration of 3 different doses (1, 2, and 4 mg/kg) of tramadol using 6 cynomolgus monkeys. The relationship between dose and occupancy for serotonin transporter and norepinephrine transporter was estimated. Results: Tramadol occupied similarly both serotonin transporter (40%-72%) and norepinephrine transporter (7%-73%) in a dose-dependent manner. The Kd was 2.2 mg/kg and 2.0 mg/kg for serotonin transporter and norepinephrine transporter, respectively. Conclusions: Both serotonin transporter and norepinephrine transporter of in vivo brain were blocked at >70% at a clinically relevant high dose of tramadol. This study suggests tramadol has potential antidepressant effects through the inhibition of serotonin transporter and norepinephrine transporter in the brain.
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