Comparison of behavioral effects of systemic L-DOPA and intracranial dopamine in mesolimbic forebrain of nonhuman primates.
The systemic administration of L-DOPA and carbidopa to six rhesus and four squirrel monkeys produced an initial period of depressed activity followed by increased locomotion, hypervigilance, involuntary oral-facial movements and a gnawing syndrome. The squirrel monkey exhibited a depressed phase, locomotor stimulation, searching behavior, stereotypic grooming and gnawing syndrome. Most of these activities were prevented by pretreatment with 0.1 mg/kg haloperidol. Bilateral injection of 100 microgram dopamine into the mesolimbic forebrain of four squirrel monkeys also produced an initial depression followed by hyperactivity similar to that produced by L-DOPA, but without gnawing. A stereotyped submissive or juvenile posturing occurred in three animals. These DA-induced activities were blocked by 0.1 mg/kg haloperidol. Similar injection of 100 microgram L-norepinephrine produced a profound depression followed by moderate activity coupled with loss of extensor muscle strength in the legs. Bilateral injection of 300 microgram dopamine into the nucleus accumbens of a rhesus monkey produced stereotypic pacing. These data confirm in primates the importance of dopaminergic mechanisms of the mesolimbic forebrain in locomotor activity and behavior.
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004298:Dopamine / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D000882:Haplorhini; D007267:Injections; D007980:Levodopa / Q000008:administration & dosage / Q000494:pharmacology*; D008032:Limbic System; D008253:Macaca mulatta; D008297:Male; D012453:Saimiri
D007980:Levodopa; D004298:Dopamine