Evidence of the involvement of D1 dopamine receptors in PCP-induced stereotypy and ataxia in rabbits.
A behavioural study on the effects of D1 and D2 dopamine receptor antagonists (SCH 23390 and sulpiride respectively) and of an A1 adenosine receptor agonist (N6-L-phenylisopropyladenosine, L-PIA) against phencyclidine (PCP)-induced effects was assessed in adult male rabbits. SCH 23390 (0.003-0.01 mg/kg i.v.) and sulpiride (12.5 mg/kg i.v.) were able to significantly prevent PCP-induced stereotypy. Ataxia was reduced by SCH 23390 (0.003 mg/kg i.v.), while it was potentiated by sulpiride (12.5 mg/kg i.v.). Given alone at 12.5 mg/kg, sulpiride induced some EEG and behavioural effects in rabbits, while SCH 23390 (0.003 and 0.01 mg/kg) did not. L-PIA prevented both PCP-induced stereotypy and ataxia at the dose (0.1 mg/kg i.v.) devoid of behavioural or EEG effects by itself. Our results suggest that D1 dopamine receptors might play a more important role than D2 receptors in the expression of PCP-induced behaviour. They also propose that A1 adenosine receptors might be involved (e.g. via an influence on the dopamine release) in the behavioural effects of PCP.
Popoli
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Laboratorio di Farmacologia, Instituto Superiore di Sanità, Roma, Italy.
Caporali
M G
MG
Scotti de Carolis
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A
D000818:Animals; D001259:Ataxia / Q000139:chemically induced* / Q000503:physiopathology; D001552:Benzazepines / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004569:Electroencephalography; D008297:Male; D010622:Phencyclidine / Q000494:pharmacology*; D010660:Phenylisopropyladenosine / Q000494:pharmacology; D011817:Rabbits; D011954:Receptors, Dopamine / Q000187:drug effects*; D013239:Stereotyped Behavior / Q000187:drug effects*; D013469:Sulpiride / Q000494:pharmacology
D001552:Benzazepines; D011954:Receptors, Dopamine; D010660:Phenylisopropyladenosine; D013469:Sulpiride; D010622:Phencyclidine