Objective: To investigate the effect of different components of Acori Tatarinowii Rhizoma-Polygalae Radix (volatile oil

aqueous extract) on learning and memory capacity as well as hippocampal synaptic proteins expression in Alzheimer's disease (AD) model rats. Method: Sprague Dawley rats (Grade:SPF) were randomly divided into 8 groups:normal group

dementia model group

Acori Tatarinowii Rhizoma-Polygalae Radix volatile oil low

middle

high dosage groups. and Acori Tatarinowii Rhizoma-Polygalae Radix aqueous extract low

middle

high dosage groups. Subacute aging models were established by D-galactose (D-gal). After successful modeling

the rats in treatment groups were given with different components of Acori Tatarinowii Rhizoma-Polygalae Radix 0.6

1.2

1.8 g · kg-1 (crude drug dosage) by gastric lavage;while the rats in normal group and model group were given with corresponding dose of normal saline. The 28 days later

their ability of spatial learning and memory was tested by Morris water maze in rats

and hippocampal synaptic protein levels in rats of various groups were detected by Western blot. Result: Compared with normal group

the latency period was prolonged in model group (P<0.01). Compared with the model group

the latency period was shortened in drug treatment groups (P<0.01). The latency period in Acori Tatarinowii Rhizoma-Polygalae Radix aqueous extract high dose group was shorter than that in low dose group and all volatile oil groups (P<0.05). In spatial probe test

aqueous extract high dose group was significantly superior to its low dose group (P<0.01) and all volatile oil groups (P<0.05). Both components of Acori Tatarinowii Rhizoma-Polygalae Radix can make the expressions of Synaptophysin

Synapsin1

PSD-95

and PSD-93 in AD model rats higher than those of D-gal model rats (P<0.05)

with a dose-dependent relationship

but the Synapsin1 expression of volatile oil was decreased with the increase of dose. Conclusion: Acori Tatarinowii Rhizoma-Polygalae Radix can promote synaptic proteins expression in the hippocampus of AD model rats

especially the aqueous extract component has the greatest effect.