Satiety threshold during maintained cocaine self-administration in outbred mice

Male Swiss Webster mice maintained cocaine self-administration in a regular and dose-dependent manner. These characteristics made it possible to apply the satiety threshold model of drug self-administration developed recently for cocaine self-administration in rats. Non-linear regression analysis revealed that cocaine satiety threshold was 1.3 +/- 0.6 mg/kg and the functional half-life of the cocaine was 8.1 +/- 2.2 min. Whether the self-administration of cocaine was maintained by lever presses or nose pokes did not influence the inter-injection intervals. The results are consistent with the pharmacological model of maintained cocaine self-administration. The ability to determine addiction-relevant phenotypes (the satiety threshold and functional half-life of cocaine) in inbred strains of mice may help to identify the genetic determinants of cocaine self-administration behavior.