Reinstatement of extinguished cocaine-taking behavior by cocaine and caffeine.
Interactions between caffeine and cocaine have been demonstrated in a number of behavioral paradigms. The present study was undertaken in an attempt to determine whether caffeine could reinstate extinguished cocaine-taking behavior in rats. Experienced self-administering rats were first put through extinction training. The rats were then given an injection of either saline, cocaine (5.0, 10.0, or 20.0 mg/kg), or caffeine (5.0, 10.0, 20.0, 40.0 mg/kg). Both cocaine and caffeine induced a dose-dependent increase in the number of responses made on the previously cocaine-associated lever. These results confirm findings that the originally self-administered drug can serve as a prime to reinstate drug-taking behavior, and that nondopaminergic agonists can also provide an effective prime to reinstate responding. Potential mechanisms for these effects are discussed.
Texas A&M University, Department of Psychology, College Station 77843.
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CM
Worley
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A
Valadez
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Schenk
D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D003042:Cocaine / Q000008:administration & dosage / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005108:Extinction, Psychological; D007275:Injections, Intravenous; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012054:Reinforcement, Psychology; D012646:Self Administration / Q000523:psychology
D002110:Caffeine; D003042:Cocaine