Objective: To explore the impact of Rubus chingii Hu's effective parts on kidney-yang deficiency Alzheimer's disease(AD) rats caused by D-galactose combined with hydrocortisone

and clarify the active ingredient of raspberry in anti-kidney-yang deficiency AD. Method: Rats were injected intraperitoneally with D-galactose in dose of 125 mg·kg-1 for six weeks. All rats were intramuscularly injected with hydrocortisone 25 mg·kg-1 for the last two weeks to establish the rat kidney-yang deficiency AD model. The blank group and the model group were given with saline

other groups were administrated with R. chingii high-dose group(24 g·kg-1)

R. chingii low-dose group(12 g·kg-1)

ethyl acetate high-dose group(24 g·kg-1)and ethyl acetate low dose-group(12 g·kg-1)for 4 weeks. After Morris water maze test

acetylcholinesterase(AchE) and choline acyltransferase(ChAT) activity of the cortex was detected. The hippocampal CA1 region for HE staining was observed and tau protein content was assayed with immunohistochemical method. Result: The R. chingii high-dose group

R. chingii low-dose group

ethyl acetate high dose group and ethyl acetate low dose group could improve the learning and memory abilities reduce cortex AchE activity and increase ChAT activity. The total numbers of cells in the hippocampus CA1 area were increased

the necrotic cells and the cell necrosis rat were decreased. Pser404-tau positive cells of the hippocampus CA1 area were decreased. Conclusion: R. chingii effective parts can improve learning and memory abilities of kidney-yang deficiency AD rats by reducing AchE activity

increasing ChAT activity

protecting neurons of hippocampal CA1 area and decreasing tau protein expression.