Effects of dopamine antagonists with different receptor blockade profiles on morphine-induced place preference in male mice.
The effects of dopamine (DA) antagonists with different selectivity for the DA receptors (SCH 23390, 0.5, 0.25, 0.125 mg/kg; haloperidol, 0.2, 0.1 mg/kg; raclopride, 1.2, 0.6, 0.3 mg/kg; risperidone, 0.4, 0.2, 0.1 mg/kg; U-99194A maleate, 40, 20 mg/kg; clozapine, 2.5, 1.25, 0.625 mg/kg) on the acquisition of place conditioning and morphine-induced conditioned place preference (CPP) were explored in male mice. Morphine (40 mg/kg) produced CPP while SCH 23390, haloperidol and clozapine (highest dose) and risperidone (lowest dose) produced conditioned place aversion (CPA). Raclopride and U-99194A maleate did not produce CPP or CPA. Morphine-induced CPP was reversed by the administration of SCH 23390 and risperidone (all doses), haloperidol (highest dose) and raclopride and clozapine (intermediate and lowest doses). U-99194A maleate did not reverse morphine-induced CPP. These results suggest that the conditioned rewarding effects of morphine are mediated by the different subtypes of DA receptors.
Area de Psicobiología, Facultad de Psicología, Universitat de Valencia, Aptdo. 22109,. 46071 Valencia, Spain.
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Manzanedo
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Aguilar
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Rodríguez-Arias
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Miñarro
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001921:Brain / Q000187:drug effects; D002755:Choice Behavior / Q000187:drug effects*; D003214:Conditioning, Classical / Q000187:drug effects; D018492:Dopamine Antagonists / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D051379:Mice; D009020:Morphine / Q000494:pharmacology*; D009042:Motivation; D009949:Orientation / Q000187:drug effects*; D011954:Receptors, Dopamine / Q000145:classification / Q000187:drug effects*
D018492:Dopamine Antagonists; D011954:Receptors, Dopamine; D009020:Morphine