Cocaine-seeking by rats: regulation, reinforcement and activation

Olmstead, M.C.; Parkinson, J.A.; Miles, F.J.; Everitt, B.J.; Dickinson, A.
October 2000
Psychopharmacology;2000, Vol. 152 Issue 2, p123
Academic Journal
Abstract Rationale: In animal models of drug self-administration, response rates often decrease with dose suggesting that a regulative process may mask the reinforcing effects of the drug. Objective: The purpose of the present experiments was to dissociate the role of regulative and reinforcement processes in intravenous cocaine sell-administration by rats using a paradigm that explicitly distinguishes between drug-seeking and drug-taking. Methods: Rats were trained to respond for intravenous cocaine (0.25 mg/infusion) under a heterogeneous chain (tandem FR1 RI 30 s) FR1 schedule of reinforcement using different levers in the first (seeking) and second (taking) links of the chain. After 10 days of training, rats were switched to one of three doses of cocaine (0.08, 0.25, or 0.5 mg/infusion) and self-administration patterns were recorded for a further ten sessions in experiment 1. In experiment 2, a time-out (TO) period (0, 4, or 12 min) was imposed between successive cycles of the chain schedule. Finally, the effect of allowing animals to perform a drug-taking response on subsequent drug-seeking was assessed in experiment 3. Results: Having verified that seeking responses for a conventional reinforcer (sucrose) were sensitive to changes in reward magnitude, experiment I demonstrated that the number of self-administered infusions was inversely related to dose whereas the latency to initiate drug-seeking increased with dose. Variations in the cocaine dose had no reliable effect on the number of drug seeking response per cycle of the chain schedule. The effect of dose on the latency to initiate drug-seeking was reversed in experiment 2 with increasing TO periods. Moreover, at the longest TO period, drug-seeking responses per cycle increased and the latency to initiate drug seeking decreased with dose....


Related Articles

  • The Role of Acetylcholine in Cocaine Addiction. Williams, Mark J.; Adinoff, Bryon // Neuropsychopharmacology;Aug2008, Vol. 33 Issue 9, p1779 

    Central nervous system cholinergic neurons arise from several discrete sources, project to multiple brain regions, and exert specific effects on reward, learning, and memory. These processes are critical for the development and persistence of addictive disorders. Although other...

  • Effects of sex and the estrous cycle on regulation of intravenously self-administered cocaine in rats. Lynch, Wendy J.; Arizzi, Maria N.; Carroll, Marilyn E. // Psychopharmacology;2000, Vol. 152 Issue 2, p132 

    Abstract Rationale: Previous research with both humans and animals suggests that there are sex differences in cocaine sell-administration; in rodents, ovarian hormones may underlie these differences. Objectives: A two-lever drug self-administration procedure was used to compare regulation of...

  • COCAINE. Tatum IV, William O.; Kaplan, Peter W.; Jallon, Pierre // Epilepsy A to Z: A Concise Encyclopedia;2009, p79 

    An encyclopedia entry for "cocaine" is presented. It refers to a central nervous system stimulant. It is one of the most abused drugs in the U.S. with a high risk of seizures when used. About 10% of patients may experience seizures, which are usually solitary and generalized convulsive. An...

  • Cocaine Addiction. Stevens, Lise M.; Lynm, Cassio; Glass, Richard M. // JAMA: Journal of the American Medical Association;1/2/2002, Vol. 287 Issue 1, p146 

    Presents information for patients about addiction to cocaine, a stimulant and highly addictive drug. Immediate effects of taking cocaine, including fast heartbeat and breathing; Long-term effects of cocaine use, including psychological and physical effects; Treatment for cocaine addiction,...

  • Neural Correlates of Reward-Based Spatial Learning in Persons with Cocaine Dependence. Tau, Gregory Z; Marsh, Rachel; Wang, Zhishun; Torres-Sanchez, Tania; Graniello, Barbara; Hao, Xuejun; Xu, Dongrong; Packard, Mark G; Duan, Yunsuo; Kangarlu, Alayar; Martinez, Diana; Peterson, Bradley S // Neuropsychopharmacology;Feb2014, Vol. 39 Issue 3, p545 

    Dysfunctional learning systems are thought to be central to the pathogenesis of and impair recovery from addictions. The functioning of the brain circuits for episodic memory or learning that support goal-directed behavior has not been studied previously in persons with cocaine dependence (CD)....

  • Initial D2 Dopamine Receptor Sensitivity Predicts Cocaine Sensitivity and Reward in Rats. Merritt, Kathryn E.; Bachtell, Ryan K. // PLoS ONE;Nov2013, Vol. 8 Issue 11, p1 

    The activation of dopamine receptors within the mesolimbic dopamine system is known to be involved in the initiation and maintenance of cocaine use. Expression of the D2 dopamine receptor subtype has been implicated as both a predisposing factor and consequence of chronic cocaine use. It is...

  • The Impact of Disulfiram Treatment on the Reinforcing Effects of Cocaine: A Randomized Clinical Trial. Haile, Colin N.; De La Garza II, Richard; Mahoney III, James J.; Nielsen, David A.; Kosten, Thomas R.; Newton, Thomas F. // PLoS Clinical Trials;Nov2012, Vol. 7 Issue 11, p1 

    Background: Clinical trials indicate that disulfiram (250 mg/d) reduces cocaine use, though one study found that treatment with lower doses of disulfiram (62.5 and 125 mg/d) increased cocaine use. We conducted the present study to better understand how disulfiram alters the reinforcing effects...

  • speed stimulant drugs.  // All About Speed: A Special Report for Young People;2000, p1 

    The article presents some facts on speed stimulant drugs. The rush is also the riskiest time for users, because that is the time when blood pressure and heart rate soar, sometimes completely off the charts. And that is when cocaine is most likely to turn our aforementioned heroes into zeroes and...

  • fast facts.  // Cocaine Fast Facts;2011, p1 

    The article provides information on cocaine, which is almost a combination of two drugs that gives a stimulant and anesthetic effects in a single molecule. It states that cocaine derives from the leaves of the coca bush or the Erythroxylum coca that grows in Peru and Brazil. It adds that the...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics