ArticlePsychopharmacology2015
The effect of acute morphine on delay discounting in dependent and non-dependent 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 6 papers.
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Who cites it
6 citing papers in PubMed, 12 citations in OpenAlex.
- The enduring legacy of Peter B. Dews: Rate-dependency and impulsive choice.The Journal of pharmacology and experimental therapeutics · 2025Review
- Impairment of value-based decision-making in morphine-dependent rats is partly related to neural connectivity between the anterior cingulate cortex and basolateral amygdala.EXCLI journal · 2024Article
- Mechanisms of impulsive choice: Experiments to explore and models to map the empirical terrain.Learning & behavior · 2023Review
- A Novel Morphine Drinking Model of Opioid Dependence in Rats.International journal of molecular sciences · 2022Article
- Effects of opioid/cannabinoid mixtures on impulsivity and memory in rhesus monkeys.Behavioural pharmacology · 2020Article
- Article
Corrections and comments
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Authors and funding
2 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
rationaleChronic opiate use is associated with increased impulsivity in both humans and animals, and previous studies suggest that acute morphine can increase impulsivity in non-dependent rats. However, the extent to which chronic opiate usage modulates the effect of acute morphine is unknown.
methodsRats were trained to delay discount 20 % sucrose solution and then randomly assigned to either a dependent group that received a nightly 30 mg/kg subcutaneous dose of morphine or a non-dependent group that received a nightly saline injection. Once dependence was established, rats were then assigned to one of four acute morphine doses (0, 1.25, 2.5, 5 mg/kg). For 5 days, delay discounting curves were determined 22.5 h after maintenance doses and 1 h after their prescribed acute injections.
resultsIn non-dependent rats, 2.5 and 5 mg/kg doses of morphine caused decreased preference for the large reward at all delays. Acute morphine had no effect on discounting curves in dependent rats.
conclusionsMorphine dependence can cause tolerance to the effects of acute morphine on delay discounting.
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Registered trials
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