title: N-methyl-D-aspartate receptor antagonist and dopamine D1 and D2 agonist interactions in 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine-induced hemiparkinsonian monkeys.
abstract: The noncompetitive N-methyl-D-aspartate antagonist (5R,10S)-(+)-5-methyl- 10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-801) and three dopamine agonists [(+/-)6-chloro-7,8-dihydroxy-2,3,4,5-tetrahydro-1-phenyl-1H-3-benzazepin e hydrobromide (SKF-81297), (+/-)6,chloro-7,8-dihydroxy-3-allyl-1-phenyl-2,3,4,5- tetrahydro-1H-3-benzazepine hydrobromide (SKF-82958) selective for D1 and (-)-2-[N-propyl-N-(2-thienyl)ethyl-amino-5- hydroxytetralin] hydrochloride (N-0923) selective for D2 receptors] were studied in seven adult female hemiparkinsonian Macaca nemestrina monkeys. Video recordings of free circling behavior showed that both SKF-82958 and N-0923 produced dose-related mean increases in contraversive rotations during the 120-min period after i.m. injection. SKF-81297 (21.1, 67.8 and 210.7 micrograms/kg) was relatively inactive compared to SKF-82958 (24.8, 74.8 and 234 micrograms/kg). The selective D2 agonist N-0923 (3.2, 10 and 32 micrograms/kg, i.m.) was the most potent in producing contraversive circling behavior. The noncompetitive N-methyl-D-aspartate antagonist dizocilpine (MK-801), in doses of 10 and 32 micrograms/kg i.m., produced a very slight increase in contraversive circling in contrast to the selective dopamine agonist SKF-82958. A large dose (100 micrograms/kg, i.m.) of MK-801 produced marked central nervous system depression. In combination with the dopamine agonists N-0923 and SKF-82958, MK-801 depressed contraversive circling in all doses studied. This study using hemiparkinsonian monkeys does not support the suggestion that a noncompetitive N-methyl-D-aspartate antagonist such as MK-801 would be useful in adjunctive therapy of human Parkinson's disease.
authors.affiliation: Department of Pharmacology, University of Michigan, Ann Arbor.
authors.forename: E F
authors.initials: EF
authors.lastname: Domino
authors.forename: J
authors.initials: J
authors.lastname: Sheng
mesh_terms: D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004195:Disease Models, Animal; D016291:Dizocilpine Maleate / Q000494:pharmacology; D015259:Dopamine Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005260:Female; D014644:Genetic Variation / Q000502:physiology; D008124:Locomotion / Q000187:drug effects; D008254:Macaca nemestrina; D009043:Motor Activity / Q000187:drug effects; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D017447:Receptors, Dopamine D1 / Q000502:physiology*; D017448:Receptors, Dopamine D2 / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*
chemical_list: D015259:Dopamine Agents; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine