Objective: To investigate the effects of Liuwei Dihuang Wan on learning and memory abilities and activity of cholinergic system in APP/PS1 mice. Method: 40 double transgenic APP/PS1 mice were randomly divided into APP/PS1 model group

Liuwei Dihuang Wan low dose group (0.59 g·kg-1·d-1)

medium dose group (1.18 g·kg-1·d-1)

and high dose group (2.36 g·kg-1·d-1)

ibuprofen group (0.04 g·kg-1·d-1)

with 8 mice in each group. Another 8 3 month old wild type mice (WT) were selected as the normal group. After lavage administration for 3 months

Morris water maze was used to test their learning and memory abilities. The content of acetylcholine (ACh) and the activity of choline acetyltransferase (ChAT) and acetylcholinesterase(AChE) in cortex were measured by enzyme-linked immunosorbant assay(ELISA). Result: Compared with the normal control group

the time required to find the platform (latency) was longer in the model group of each period (P<0.05);time and percentage of staying in platform quadrant and frequency of crossing the platform were decreased (P<0.05);content of ACh and activity of ChAT were decreased (P<0.05). Compared with the APP/PS1 model group

latency was shortened (P<0.05)

time and percentage of staying in platform quadrant and frequency of crossing the platform were increased (P<0.05) in Liuwei Dihuang Wan low

medium and high dose groups as well as ibuprofen group;the content of ACh and the activity of ChAT were increased (P<0.05)

while the activity of AChE was not significantly different. Conclusion: Different doses of Liuwei Dihuang Wan can improve learning and memory abilities of APP/PS1 mice

which is related to its effects on the cholinergic system by increasing the content of ACh and the activity of ChAT.