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07:51
A Protocol for Measuring Cue Reactivity in a Rat Model of Cocaine Use Disorder
Published on: June 18, 2018
Stability of cocaine dose-response functions at different inter-dose intervals
Julie A Marusich1, Marc N Branch
1Psychology Department, University of Florida, PO Box 112250, Gainesville, FL 32611, USA. marusich@ufl.edu
Pharmacology, Biochemistry, and Behavior
|July 14, 2006
Summary
Frequent cocaine administration in pigeons did not lead to tolerance, suggesting that the drug regimen, not just dose variation, influences tolerance development. This impacts understanding cocaine
Area of Science:
- Behavioral pharmacology
- Neuroscience
- Drug addiction research
Background:
- Previous studies indicate daily cocaine administration can cause tolerance to its behavioral effects.
- Tolerance to cocaine can develop even with variable daily dosing schedules.
Purpose of the Study:
- To investigate the impact of varied cocaine doses and inter-dose intervals on tolerance development in pigeons.
- To determine if frequent administration prevents tolerance, unlike less frequent dosing.
Main Methods:
- Pigeons were trained on a fixed-ratio 20 schedule of reinforcement.
- Cocaine or saline vehicle was administered at intervals of once per week, every fourth day, every 2 days, and daily.
- Dose-response functions were assessed across four experimental phases to evaluate tolerance.
Main Results:
- Dose-response curves for cocaine remained consistent within and across all experimental phases.
- No subjects developed tolerance when cocaine was administered every fourth day, every 2 days, or daily.
- One subject developed tolerance during the once-per-week dosing phase.
Conclusions:
- Frequent administration of cocaine (every 2 days or daily) prevented tolerance development in pigeons.
- The inter-dose interval, not just dose variability, appears critical in preventing cocaine tolerance.
- Findings suggest specific drug regimens can mitigate tolerance, offering insights into addiction mechanisms.
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