Reinforcing properties of some opiates and opioids in rhesus monkeys with histories of cocaine and codeine self-administration

✍ Scribed by F. Hoffmeister; U. U. Schlichting

• Publisher: Springer
• Year: 1972
• Tongue: English
• Weight: 947 KB
• Volume: 23
• Category: Article
• ISSN: 0033-3158
• DOI: 10.1007/bf00414414

✦ Synopsis

l%hesus monkeys were conditioned to press a key to selfadminister intravenous injections of either cocaine (8 monkeys) or codeine (7 monkeys). Every tenth lever press resulted in an injection of 50 mcg/kg/inj, cocaine or codeine during daily 3 h sessions. Equal doses of cocaine and codeine generated regular comparable rates of self-administration responding. After responding stabilized, different narcotic and non-narcotic analgesics (morphine, codeine, detropropoxyphene, propiramfumarate, pentazocine and nalorphine) were substitu~d for cocaine or codeine. At appropriate doses all drugs except for nMorphine, maintained selfadministration responding. Monkeys with a codeine self-administration history self-administered higher numbers of injections and showed less intraindividual variability than monkeys with a cocaine self-administration history.