Cocaine's effects on rate of intracranial self-stimulation

• Published in: Pharmacology, biochemistry and behavior Vol. 40; no. 2; pp. 273 - 277
• Main Authors: Williams, Henry P., Manderscheid, Patricia Z., Schwartz, Marvin, Frank, Robert A.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.10.1991; Elsevier Science
• Subjects: Animals; Biological and medical sciences; Brain stimulation reward; Cocaine; Cocaine - pharmacology; Conditioning, Operant - drug effects; Drug addictions; Drugs of abuse; Electric Stimulation; Male; Medical sciences; Rats; Rats, Inbred Strains; Response requirements; Self Stimulation - drug effects; Self-stimulation; Stereotyped Behavior - drug effects; Toxicology; Response requirements; Cocaine; Self-stimulation; Drugs of abuse; Brain stimulation reward; Intraperitoneal administration; Operant conditioning; Methodology; Rat; CNS stimulant; Psychotropic; Rodentia; Vertebrata; Alkaloid; Mammalia; Acquisition process; Animal; Self stimulation; Reinforcement; Drug of abuse
• ISSN: 0091-3057; 1873-5177
• DOI: 10.1016/0091-3057(91)90551-C

While some investigators have reported that cocaine increases response rates for brain stimulation reward, others have failed to demonstrate this effect. The present study was designed to evaluate the influence of stimulation parameters, dose of cocaine and operant-dependent response requirements on cocaine's ability to alter self-stimulation rates. Self-stimulation rates were collected on a minute by minute basis for 45 min following IP injections of 0, 5, 15 or 30 mg/kg cocaine HCl. All doses were tested using both nose-poking and lever-pressing operants. It was found that mean lever-pressing rates were significantly increased by 5 mg/kg cocaine, while nose-poking rates were significantly increased by 15 and 30 mg/kg cocaine. Further examination of the pattern of results indicated that the cocaine-induced increases in lever-pressing rate were mainly due to an increase in the time spent self-stimulating, whereas increases in nose-poking were mainly due to increases in nose-poking rate/min within self-stimulation bouts. It was hypothesized that 5 mg/kg cocaine increased lever-pressing by producing response perservation, while the higher doses increased nose-poking mainly due to the compatibility of the nose-poking response topography with cocaine-induced stereotypies.