Dehydroevodiamine attenuates β-amyloid peptide-induced amnesia in mice

Dehydroevodiamine has been reported to have anticholinesterase activity and an anti-amnesic effect. This study examined the effects of dehydroevodiamine on scopolamine- and beta -amyloid peptide-(25-35)-induced amnesia in mice, using a step-through passive avoidance test. Similarly to the cholinesterase inhibitor, physostigmine (0.03-0.3 mg/kg, i.p.), dehydroevodiamine (0.75-12.0 mg/kg, i.p.) administered 30 min before the training trial, immediately after the training trial, and 30 min before the retention test significantly improved scopolamine- and beta -amyloid peptide-(25-35)-induced amnesia. In beta -amyloid peptide-(25-35)-induced amnesia, the rank order of anti-amnesic potency in these three administration schedules for dehydroevodiamine was different from that for physostigmine. Furthermore, dehydroevodiamine was more potent to improve beta -amyloid peptide-(25-35)-induced amnesia than scopolamine-induced amnesia when administered before the training trial. These results suggested that dehydroevodiamine may have an action other than that of an anticholinesterase and may be a novel and effective ligand for improvement of beta -amyloid type amnesia. (C) 2001 Elsevier Science B.V. All rights reserved.