8-OH-DPAT-induced place preference and place aversion: effects of PCPA and dopamine antagonists.
Low doses of 8-OH-DPAT (62.5-250 micrograms/kg) were reinforcing in the place preference conditioning procedure, while a higher dose (1 mg/kg) supported a conditioned place aversion. The 5-HT synthesis inhibitor PCPA, and the DA antagonists pimozide and sulpiride, had no effect when administered alone, but abolished the 8-OH-DPAT-induced place preference. However, neither PCPA nor pimozide altered the 8-OH-DPAT-induced place aversion. The results are consistent with other evidence showing that 8-OH-DPAT acts through different mechanisms at low and high doses, and support the hypothesis that low doses of 8-OH-DPAT act through 5-HT neurons to disinhibit dopaminergic activity.
Papp
M
M
Department of Psychology, City of London Polytechnic, UK.
Willner
P
P
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D003216:Conditioning, Operant / Q000187:drug effects*; D018492:Dopamine Antagonists; D010134:Fenclonine / Q000494:pharmacology; D008297:Male; D010868:Pimozide / Q000494:pharmacology; D051381:Rats; D012702:Serotonin Antagonists / Q000494:pharmacology*; D013469:Sulpiride / Q000494:pharmacology; D013764:Tetrahydronaphthalenes / Q000037:antagonists & inhibitors / Q000494:pharmacology*
D018492:Dopamine Antagonists; D012702:Serotonin Antagonists; D013764:Tetrahydronaphthalenes; D010868:Pimozide; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D013469:Sulpiride; D010134:Fenclonine