Satiety threshold during maintained cocaine self-administration in outbred mice

Area of Science:

• Neuroscience
• Pharmacology
• Behavioral Science

Background:

• Cocaine self-administration is a key model for studying addiction.
• Understanding the factors that regulate drug intake is crucial for developing effective treatments.

Purpose of the Study:

• To apply the satiety threshold model to cocaine self-administration in male Swiss Webster mice.
• To determine the cocaine satiety threshold and functional half-life in this model.
• To explore the influence of different self-administration methods (lever press vs. nose poke) on cocaine intake.

Main Methods:

• Male Swiss Webster mice were trained to self-administer cocaine.
• The satiety threshold model was applied using non-linear regression analysis.
• Inter-injection intervals were analyzed in relation to self-administration methods.

Main Results:

• Cocaine self-administration was maintained in a regular and dose-dependent manner.
• The cocaine satiety threshold was determined to be 1.3 +/- 0.6 mg/kg.
• The functional half-life of cocaine was found to be 8.1 +/- 2.2 min.
• The method of self-administration (lever press or nose poke) did not affect inter-injection intervals.

Conclusions:

• The satiety threshold model is applicable to cocaine self-administration in mice.
• The determined satiety threshold and functional half-life provide addiction-relevant phenotypes.
• These findings support the pharmacological model of cocaine self-administration.
• Identifying genetic determinants of cocaine self-administration behavior in mice is feasible.