Effect of nondopaminergic drugs on L-dopa-induced dyskinesias in MPTP-treated monkeys.
A group of four monkeys was rendered parkinsonian with the toxin MPTP. They were then treated chronically with L-DOPA/benserazide 50/12.5 mg/kg given orally daily for 2 months. This dose produced a striking antiparkinsonian effect, but all animals manifested dyskinesia. A series of agents acting primarily on neurotransmitters other than dopamine were then tested in combination with L-DOPA to see if the dyskinetic movements would be modified. Several drugs, including clonidine, physostigmine, methysergide, 5-MDOT, propranolol, and MK-801, markedly reduced the dyskinetic movements but at the cost of a return of parkinsonian symptomatology. However, yohimbine and meperidine reduced predominantly the dyskinetic movements. Baclofen was also useful in one monkey against a more dystonic form of dyskinesia. Atropine converted the dystonic movements into chorea.
Gomez-Mancilla
B
B
Centre de Recherche en Neurobiologie, Hôpital de l'Enfant-Jésus, Québec, Canada.
Bédard
P J
PJ
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001418:Baclofen / Q000494:pharmacology; D003000:Clonidine / Q000494:pharmacology; D015259:Dopamine Agents / Q000494:pharmacology*; D004347:Drug Interactions; D004409:Dyskinesia, Drug-Induced / Q000188:drug therapy* / Q000209:etiology; D005260:Female; D007980:Levodopa; D008252:Macaca fascicularis; D008614:Meperidine / Q000494:pharmacology; D008732:Methoxydimethyltryptamines / Q000494:pharmacology; D018377:Neurotransmitter Agents / Q000502:physiology; D015016:Yohimbine / Q000494:pharmacology
D015259:Dopamine Agents; D008732:Methoxydimethyltryptamines; D018377:Neurotransmitter Agents; D015016:Yohimbine; D007980:Levodopa; D001285:Atropine; D008614:Meperidine; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D001418:Baclofen; D003000:Clonidine