Dehydroevodiamine attenuates beta-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 dehydroevodiami ne on scopolamine- and beta -amyloid peptide-(25-35)-induced amnesia in mic e, using a step-through passive avoidance test. Similarly to the cholineste rase 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, immedia tely after the training trial, and 30 min before the retention test signifi cantly improved scopolamine- and beta -amyloid peptide-(25-35)-induced amne sia. In beta -amyloid peptide-(25-35)-induced amnesia, the rank order of an ti-amnesic potency in these three administration schedules for dehydroevodi amine was different from that for physostigmine. Furthermore, dehydroevodia mine was more potent to improve beta -amyloid peptide-(25-35)-induced amnes ia than scopolamine-induced amnesia when administered before the training t rial. These results suggested that dehydroevodiamine may have an action oth er than that of an anticholinesterase and may be a novel and effective liga nd for improvement of beta -amyloid type amnesia. (C) 2001 Elsevier Science B.V. All rights reserved.