title: Oxiracetam antagonizes the disruptive effects of scopolamine on memory in the radial maze.
abstract: The effects exerted by oxiracetam on the disruption of performance induced by scopolamine in the radial arm maze were investigated in overtrained rats. Scopolamine induced a dose-related decrease in the efficiency of responding and an increase of running time. The effect of the SC injection of 0.2 mg/kg scopolamine on the efficiency of responding was antagonized by the IP administration of 30 mg/kg oxiracetam, while the effect on running time induced by the same dose of scopolamine was not. Physostigmine (0.3 mg/kg SC) antagonized both effects of 0.2 mg/kg scopolamine. Methylscopolamine, at the dose of 0.2 mg/kg SC, was devoid of any effect on both parameters. Increasing the dose of methylscopolamine to 0.63 mg/kg did cause serious peripheral effects which eventually prevented some animals from completing the task. Similar peripheral effects were observed after administration of 0.63 mg/kg scopolamine. The effects of this dose of scopolamine on efficiency and running time were not antagonized by pretreatment with 100 mg/kg oxiracetam. Oxiracetam alone (30 or 100 mg/kg IP) did not modify the performance of previously trained rats. The present results suggest that oxiracetam selectively restores cholinergic mechanisms which are involved in learning and memory.
authors.affiliation: ISF Laboratories for Biomedical Research, Milano, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Magnani
authors.forename: O
authors.initials: O
authors.lastname: Pozzi
authors.forename: R
authors.initials: R
authors.lastname: Biagetti
authors.forename: S
authors.initials: S
authors.lastname: Banfi
authors.forename: L
authors.initials: L
authors.lastname: Dorigotti
mesh_terms: D000818:Animals; D004305:Dose-Response Relationship, Drug; D008297:Male; D008568:Memory / Q000187:drug effects*; D009043:Motor Activity / Q000187:drug effects; D019832:N-Methylscopolamine; D010275:Parasympathetic Nervous System / Q000187:drug effects; D010276:Parasympatholytics / Q000494:pharmacology; D010830:Physostigmine / Q000494:pharmacology; D011619:Psychotropic Drugs / Q000494:pharmacology*; D011759:Pyrrolidines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012601:Scopolamine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D012602:Scopolamine Derivatives / Q000494:pharmacology
chemical_list: D010276:Parasympatholytics; D011619:Psychotropic Drugs; D011759:Pyrrolidines; D012602:Scopolamine Derivatives; D010830:Physostigmine; D012601:Scopolamine; C040619:oxiracetam; D019832:N-Methylscopolamine