ArticlePsychopharmacology2016
The behavioral effects of a mixed efficacy antinociceptive peptide, VRP26, following chronic administration in mice.
Article in Psychopharmacology, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
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Who cites it
12 citing papers in PubMed.
- Enhanced antinociception of mixed efficacy opioid peptidomimetics through P-glycoprotein modulation.The Journal of pharmacology and experimental therapeutics · 2026Article
- Assessment of abuse potential of furanylfentanyl and tetrahydrofuranylfentanyl.Psychopharmacology · 2025Article
- Peptide-derived ligands for the discovery of safer opioid analgesics.Drug discovery today · 2024Review
- Claustral neurons projecting to frontal cortex restrict opioid consumption.Current biology : CB · 2023Article
- Differential Effects of a Novel Opioid Ligand UTA1003 on Antinociceptive Tolerance and Motor Behaviour.Pharmaceuticals (Basel, Switzerland) · 2022Article
- Synthesis and Pharmacology of a Novel μ-δ Opioid Receptor Heteromer-Selective Agonist Based on the Carfentanyl Template.Journal of medicinal chemistry · 2020Article
- Synthesis and Structure-Activity Relationships of 5'-Aryl-14-alkoxypyridomorphinans: Identification of a μ Opioid Receptor Agonist/δ Opioid Receptor Antagonist Ligand with Systemic Antinociceptive Activity and Diminished Opioid Side Effects.Journal of medicinal chemistry · 2020Article
- Behavioral pharmacology of the mixed-action delta-selective opioid receptor agonist BBI-11008: studies on acute, inflammatory and neuropathic pain, respiration, and drug self-administration.Psychopharmacology · 2020Article
- In vivo effects of μ-opioid receptor agonist/δ-opioid receptor antagonist peptidomimetics following acute and repeated administration.British journal of pharmacology · 2018Article
- Delta/mu opioid receptor interactions in operant conditioning assays of pain-depressed responding and drug-induced rate suppression: assessment of therapeutic index in male Sprague Dawley rats.Psychopharmacology · 2018Article
- Novel Molecular Strategies and Targets for Opioid Drug Discovery for the Treatment of Chronic Pain.The Yale journal of biology and medicine · 2017Review
- A Novel Mu-Delta Opioid Agonist Demonstrates Enhanced Efficacy With Reduced Tolerance and Dependence in Mouse Neuropathic Pain Models.The journal of painArticle
Corrections and comments
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Authors and funding
4 authors.
Funding
Abstract
rationaleVRP26 displays mu opioid receptor agonist and delta opioid receptor antagonist activity in vitro, a pharmacological profile purported to produce reduced tolerance, dependence, and rewarding effects. We hypothesized that VRP26 would display reduced adverse effects after chronic administration as compared with the traditional opioid analgesic fentanyl.
objectiveThe aim of this study is to explore the development of tolerance, dependence, and conditioned place preference of VRP26 as compared with the traditional opioid analgesic fentanyl.
methodsThe antinociceptive effects of VRP26 and fentanyl were assessed using the mouse warm water tail withdrawal (WWTW) assay. Measurement of antinociceptive tolerance and physical dependence occurred after 7 days of continuous administration of either fentanyl (0.3 mg/kg/day) or VRP26 (10 mg/kg/day); tolerance was measured by a shift in the antinociceptive dose response curve in the WWTW assay. Physical dependence was determined by observation of withdrawal symptoms after precipitated withdrawal. Rewarding effects were measured by the ability of VRP26 or fentanyl to produce conditioned place preference.
resultsFentanyl produced significant tolerance and dependence, as well as significant conditioned place preference. VRP26 produced neither tolerance nor physical dependence, nor did it produce significant conditioned place preference.
conclusionsThese results suggest that chronic treatment with VRP26 may produce less tolerance or physical dependence than chronic treatment with clinically available mu opioid analgesics such as fentanyl. Additionally, VRP26 produces less rewarding effects than fentanyl. This desirable in vivo profile may be due to the mixed efficacy nature of VRP26 and could provide the framework for safer opioid analgesics.
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Registered trials
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.