title: The 5-HT3 receptor antagonist, RS-56812, enhances delayed matching performance in monkeys.
abstract: Substantial evidence indicates that serotonin receptors are involved in the regulation of acetylcholine release in CNS regions important to mnemonic processes, and may thus be exploited pharmacologically as targets for memory improvement. In the present study, the (R) and (S) isomers of a potent serotonin (5-HT3) receptor ligand, RS-56812 were evaluated for potential memory effects in five macaques trained to perform a delayed matching-to-sample (DMTS) task. While both isomers enhanced certain aspects of task performance, the (R) isomer produced more systematic improvements. This differential sensitivity to the isomers in regard to DMTS performance appears to parallel the higher 5-HT3 receptor affinity of the R enanantiomer. The results are consistent with a potential therapeutic role for RS-56812 in disorders involving cognitive decline.
authors.affiliation: University of Georgia Clinical Pharmacy Program, Augusta, USA.
authors.forename: A V
authors.initials: AV
authors.lastname: Terry
authors.forename: J J
authors.initials: JJ
authors.lastname: Buccafusco
authors.forename: M A
authors.initials: MA
authors.lastname: Prendergast
authors.forename: W J
authors.initials: WJ
authors.lastname: Jackson
authors.forename: D L
authors.initials: DL
authors.lastname: Fontana
authors.forename: E H
authors.initials: EH
authors.lastname: Wong
authors.forename: R L
authors.initials: RL
authors.lastname: Whiting
authors.forename: R M
authors.initials: RM
authors.lastname: Eglen
mesh_terms: D000818:Animals; D003118:Color Perception / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D007536:Isomerism; D008252:Macaca fascicularis; D008254:Macaca nemestrina; D008297:Male; D008568:Memory / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects*; D011812:Quinuclidines / Q000494:pharmacology*; D012702:Serotonin Antagonists / Q000494:pharmacology*; D013268:Stimulation, Chemical
chemical_list: D011812:Quinuclidines; C105631:RS 56812; D012702:Serotonin Antagonists