title: Behavioral effects of D1 and D2 dopamine receptor antagonists in squirrel monkeys.
abstract: The behavioral effects of dopamine antagonists differing in affinity and selectivity at D1 and D2 dopamine receptors were compared in squirrel monkeys responding under a fixed-interval schedule of stimulus-shock termination. D1-selective antagonists included (R)-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine-7 -ol, SCH 23390; its enantiomer (S)-(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine-7 -ol, SCH 23388; [(-)-trans-6,7,7a,8,9,13b-hexahydro-3-chloro-2-hydroxy-N-methyl-5H - benzo(d)naphtho-(2,1-b)azepine], SCH 39166; (R)-7-bromo-8-hydroxyl-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzaze pine, R-SKF 83566; (R)-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine-7-ol, R-SKF 83692; 2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepine-7-ol, RS-SKF 83692. D2-selective antagonists included cis-N-(1-benzyl-2-methylpyrrolidine-3-yl)-5-chloro-2-methoxy-4- methylaminobenzamide, YM-09151-2, eticlopride, raclopride, haloperidol, risperidone, remoxipride, S-sulpiride and R-sulpiride; nonselective dopamine antagonists were S-butaclamol and chlorpromazine. Regardless of selectivity for D1 or D2 receptors, all drugs produced dose-related decreases in fixed-interval responding. A high degree of stereoselectivity was evident for both D1 antagonists (SCH 23390 and R-SKF 83692 more potent than, respectively, SCH 23388 and RS-SKF 83692) and D2 antagonists (S-sulpiride more potent than R-sulpiride). High doses of the D1 and D2 antagonists also reduced motor activity and impaired coordination in monkeys in the home cage after test sessions.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Harvard Medical School, New England Regional Primate Research Center, Southborough, MA.
authors.forename: J
authors.initials: J
authors.lastname: Bergman
authors.forename: B K
authors.initials: BK
authors.lastname: Madras
authors.forename: R D
authors.initials: RD
authors.lastname: Spealman
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D018492:Dopamine Antagonists; D004305:Dose-Response Relationship, Drug; D004597:Electroshock; D008297:Male; D011869:Radioligand Assay; D011954:Receptors, Dopamine / Q000378:metabolism; D012453:Saimiri
chemical_list: D018492:Dopamine Antagonists; D011954:Receptors, Dopamine