Pre- and post-synaptic actions of apomorphine: differentiation by rotatory effects in normal rats.
Normal rats were tested for rotation (circling behavior) following d-amphetamine (1.0 mg/kg) and, a week later, following apomorphine (10.0 mg/kg). In most rats, d-amphetamine and apomorphine elicited rotation in opposite directions whereas, in some rats, the two drugs elicited rotation in the same direction. Subsequently, alpha-methyl-p-tyrosine was found to antagonize the rotatory effect of apomorphine in the latter but not in the former rats. The results suggest that apomorphine has both pre- and post-synaptic actions and that relative sensitivity to these actions varies among rats.
D000818:Animals; D001058:Apomorphine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D001519:Behavior / Q000187:drug effects*; D003913:Dextroamphetamine / Q000494:pharmacology; D005260:Female; D006801:Humans; D008781:Methyltyrosines / Q000494:pharmacology; D009043:Motor Activity / Q000187:drug effects*; D051381:Rats; D013239:Stereotyped Behavior / Q000187:drug effects*; D013569:Synapses / Q000187:drug effects*
D008781:Methyltyrosines; D001058:Apomorphine; D003913:Dextroamphetamine