ArticlePsychopharmacology2008
Comparison of naltrexone, 6alpha-naltrexol, and 6beta-naltrexol in morphine-dependent and in nondependent rhesus monkeys.
Article in Psychopharmacology, 2008. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
What it found
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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
12 citing papers in PubMed, 17 citations in OpenAlex.
- The imidazoline IPsychopharmacology · 2024Article
- Ligand-Free Signaling of G-Protein-Coupled Receptors: Relevance to μ Opioid Receptors in Analgesia and Addiction.Molecules (Basel, Switzerland) · 2022Review
- Antinociceptive and Discriminative Stimulus Effects of Six Novel Psychoactive Opioid Substances in Male Rats.The Journal of pharmacology and experimental therapeutics · 2021Article
- Long-Lasting Effects of Methocinnamox on Opioid Self-Administration in Rhesus Monkeys.The Journal of pharmacology and experimental therapeutics · 2019Article
- Sustained opioid antagonism modulates striatal sensitivity to baby schema in opioid use disorder.Journal of substance abuse treatment · 2018Article
- Antihyperalgesic effects of imidazoline I(2) receptor ligands in rat models of inflammatory and neuropathic pain.British journal of pharmacology · 2014Article
- Eating high-fat chow increases the sensitivity of rats to quinpirole-induced discriminative stimulus effects and yawning.Behavioural pharmacology · 2010Article
- The relative potency of inverse opioid agonists and a neutral opioid antagonist in precipitated withdrawal and antagonism of analgesia and toxicity.The Journal of pharmacology and experimental therapeutics · 2009Article
- Shadows across mu-Star? Constitutively active mu-opioid receptors revisited.British journal of pharmacology · 2009Article
- Relative potency of the opioid antagonists naloxone and 6-alpha-naloxol to precipitate withdrawal from acute morphine dependence varies with time post-antagonist.Pharmacology, biochemistry, and behavior · 2009Article
- Interactions between Delta(9)-tetrahydrocannabinol and mu opioid receptor agonists in rhesus monkeys: discrimination and antinociception.Psychopharmacology · 2008Article
- Impulsivity and drugs of abuse: a juice-reinforced operant procedure for determining within-session delay discounting functions in rhesus monkeys.Journal of pharmacological and toxicological methodsArticle
Corrections and comments
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Authors and funding
3 authors at 2 institutions in 1 country.
Funding
Abstract
rationaleSome opioid receptor ligands that appear to be neutral antagonists can have inverse agonist activity under conditions of increased constitutive activity (e.g., agonist treatment).
objectivesThis study compared the opioid receptor antagonist naltrexone and its metabolites 6alpha-naltrexol and 6beta-naltrexol in nondependent and morphine-dependent monkeys to see whether their potencies varied according to drug treatment and, presumably, to differences in constitutive activity of mu opioid receptors.
resultsIn monkeys (n = 4) receiving 3.2 mg/kg per day of morphine and discriminating 0.0178 mg/kg naltrexone, naltrexone and each metabolite increased responding on the naltrexone lever in a dose-related manner with naltrexone being 8- and 71-fold more potent than 6alpha- and 6beta-naltrexol, respectively. After 27 h of no-morphine treatment, monkeys responded on the naltrexone lever, and this effect was reversed by morphine. Naltrexone and each metabolite prevented morphine reversal of naltrexone-lever responding, and their rank order potency was the same as their substitution for naltrexone; however, the potency between naltrexone and each metabolite was slightly greater in morphine-dependent as compared to morphine-deprived monkeys. In a separate group (n = 3) of nondependent monkeys discriminating 1.78 mg/kg of morphine, all three compounds antagonized morphine with the same potency as in the reversal study (morphine-dependent monkeys), with Schild analyses showing no difference in apparent affinities (pA (2)) between nondependent and morphine-dependent monkeys.
conclusionNaltrexone and 6alpha- and 6beta-naltrexol have qualitatively similar effects, and their potencies do not vary markedly with opioid treatment, suggesting that under these conditions, they do not vary with regard to inverse agonism.
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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.