ArticlePsychopharmacology2015
Discriminative stimulus properties of mitragynine (kratom) in rats.
Article in Psychopharmacology, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 29 papers, 2 of them syntheses that pooled it.
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Who cites it
29 citing papers in PubMed, 2 syntheses or guidelines pooled it, 70 citations in OpenAlex.
- Decoding kratom: molecular mechanisms and epigenetic factors in use and dependence.Translational psychiatry · 2026Pooled it
- A systematic review of (pre)clinical studies on the therapeutic potential and safety profile of kratom in humans.Human psychopharmacology · 2022Pooled it
- Kratom (Molecules (Basel, Switzerland) · 2026Article
- Mitragynine and 7-hydroxymitragynine: Bidirectional effects on breathing in rats.The Journal of pharmacology and experimental therapeutics · 2025Article
- Mitragynine and morphine produce dose-dependent bimodal action on food but not water intake in rats.American journal of physiology. Regulatory, integrative and comparative physiology · 2024Article
- The Mitragyna speciosa (kratom) alkaloid mitragynine: Analysis of adrenergic αEuropean journal of pharmacology · 2024Article
- Pharmacokinetic and Pharmacodynamic Consequences of Cytochrome P450 3A Inhibition on Mitragynine Metabolism in Rats.The Journal of pharmacology and experimental therapeutics · 2023Article
- Interactive Effects ofThe Journal of pharmacology and experimental therapeutics · 2022Article
- Physiological dependence to mitragynine indicated by a rapid cross-dependence procedure with heroin-dependent mice.Psychopharmacology · 2022Article
- Adolescent kratom exposure affects cognitive behaviours and brain metabolite profiles in Sprague-Dawley rats.Frontiers in pharmacology · 2022Article
- Searching for a Signal: Self-Reported Kratom Dose-Effect Relationships Among a Sample of US Adults With Regular Kratom Use Histories.Frontiers in pharmacology · 2022Article
- Understanding Kratom Use: A Guide for Healthcare Providers.Frontiers in pharmacology · 2022Review
- Pentylenetetrazol-like stimulus is not produced following naloxone-precipitated mitragynine withdrawal in rats.Psychopharmacology · 2021Article
- Kratom pharmacology: Clues from planarians exposed to mitragynine.Physiology & behavior · 2021Article
- Influence of G protein-biased agonists of μ-opioid receptor on addiction-related behaviors.Pharmacological reports : PR · 2021Review
- Kratom Alkaloids, Natural and Semi-Synthetic, Show Less Physical Dependence and Ameliorate Opioid Withdrawal.Cellular and molecular neurobiology · 2021Article
- The Right to Use Kratom from the Psychiatric and Islamic Perspectives.Journal of religion and health · 2021Article
- Pharmacological Comparison of Mitragynine and 7-Hydroxymitragynine: In Vitro Affinity and Efficacy forThe Journal of pharmacology and experimental therapeutics · 2021Article
- The Antidepressant-Like and Analgesic Effects of Kratom Alkaloids are accompanied by Changes in Low Frequency Oscillations but not ΔFosB Accumulation.Frontiers in pharmacology · 2021Article
- Evaluation of the rewarding effects of mitragynine and 7-hydroxymitragynine in an intracranial self-stimulation procedure in male and female rats.Drug and alcohol dependence · 2020Article
Corrections and comments
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Authors and funding
5 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
rationaleMitragynine (MG) is the primary active alkaloid extracted from the leaves of Mitragyna speciosa or kratom and exhibits pharmacological activities mediated by opioid receptors. The plant has been traditionally used for its opium and psychostimulant-like effects to increase work efficiency or as a substitute in the self-treatment of opiate addiction.
objectivesThe present study was performed to investigate the discriminative stimulus effects of MG in rats. The pharmacological mechanism of MG action and its derivative, 7-hydroxymitragynine (7-HMG) with a specific focus on opioid receptor involvement was examined in rats trained to discriminate morphine from vehicle. In order to study the dual actions of MG, the effect of cocaine substitution to the MG discriminative stimulus was also performed in MG-trained rats.
methodsMale Sprague Dawley rats were trained to discriminate MG from vehicle in a two-lever drug discrimination procedure under a tandem variable-interval (VI 60') fixed-ratio (FR 10) schedule of food reinforcement.
resultsRats acquired the MG discrimination (15.0 mg/kg, i.p.) which was similar to the acquisition of morphine discrimination (5.0 mg/kg, i.p.) in another group of rats. MG substituted fully to the morphine discriminative stimulus in a dose-dependent manner, suggesting pharmacological similarities between the two drugs. The administration of 7-HMG derivative in 3.0 mg/kg (i.p.) dose engendered full generalisation to the morphine discriminative stimulus. In addition, the MG stimulus also partially generalised to cocaine (10.0 mg/kg, i.p.) stimulus.
conclusionThe present study demonstrates that the discriminative stimulus effect of MG possesses both opioid- and psychostimulant-like subjective effects.
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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.