title: Effects of L-threo- and erythro-3,4-dihydroxyphenylserine on learning performance and concentrations of brain noradrenaline and its metabolites in rats.
abstract: Effects of L-threo and L-erythro-3,4-dihydroxyphenylserine [DOPS, precursor amino acids for noradrenaline (NA)] on the learning performance in a maze paradigm designed to model on the water maze paradigm using a multicomputerized behavioral analysis system were studied. A marked facilitation of learning performance was observed in rats after an intraventricular injection of 5 micrograms L-threo-DOPS (the s-NA precursor), and this effect was inhibited by a simultaneous administration of 1 or 2 micrograms propranolol (a beta-adrenergic antagonist). As concentrations of brain NA, 3-methoxy-4-hydroxyphenylglycol, and normethanephrine were increased by the injection of 5 micrograms L-threo-DOPS, the effect seemed to be derived from activation of beta-adrenoceptors in the CNS by the formed s-NA. On the other hand, an intraventricular injection of 5 micrograms L-erythro-DOPS (the r-NA precursor) attenuated the learning performance, and this effect was probably caused by the formed r-NA from L-erythro-DOPS.
authors.affiliation: Department of Neuropsychiatry, Kyoto Prefectural University of Medicine, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Harada
authors.forename: T
authors.initials: T
authors.lastname: Noto
authors.forename: M
authors.initials: M
authors.lastname: Tsuji
authors.forename: C
authors.initials: C
authors.lastname: Taga
authors.forename: H
authors.initials: H
authors.lastname: Hashimoto
authors.forename: T
authors.initials: T
authors.lastname: Nakajima
mesh_terms: D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism; D001923:Brain Chemistry / Q000187:drug effects*; D015103:Droxidopa / Q000494:pharmacology*; D007276:Injections, Intraventricular; D007858:Learning / Q000187:drug effects*; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009638:Norepinephrine / Q000378:metabolism*; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013237:Stereoisomerism
chemical_list: D015306:Biogenic Monoamines; D011433:Propranolol; D015103:Droxidopa; D009638:Norepinephrine