ABSTRACT
The differences in the pharmacological effects of R(+)- and S(-)-isomers of the atypical antidepressant viloxazin were discovered in two behavioral models. The S(-)-isomer appeared 5 times as active as the R(+)-isomer under acute administration. In chronic administration, (15 days), the R(+)-isomer appeared ineffective. Comparison of the affinity of the racemate, R(+) and S(-)-isomers for alpha 1-, alpha 2- and beta-adrenoreceptors, as well as for serotonin, C1, benzodiazepine, imipramine and dopamine receptors did not demonstrate any stereospecificity of viloxazin isomers. It is assumed that some other receptors (histamine, acetylcholine) present the targets for the pharmacological action of viloxazin or the latter one has, like zimelidin , specific binding sites of its own.
Subject(s)
Behavior, Animal/drug effects , Brain/drug effects , Morpholines/pharmacology , Receptors, Neurotransmitter/drug effects , Viloxazine/pharmacology , Animals , Dose-Response Relationship, Drug , Male , Mice , Mice, Inbred CBA , Radioligand Assay , StereoisomerismABSTRACT
The central neurotropic effects of 4-phenylpyracetam, a new phenyl analog of pyracetam, were studied and compared with the effects of pyracetam, morpholene and 4-phenylpyrrolidone. 4-Phenylpyracetam was found to activate the operant behavior more powerfully, to remove psychodepressant effects of diazepam, to inhibit post-rotational nystagmus, and to prevent the development of retrograde amnesia. Unlike pyracetam, 4-phenylpyracetam exhibits a specific anticonvulsant action. When given in high doses, the compound under study produces psychodepressant effects.
