Objective: To investigate the effect of compound Yishen Yangnao capsule (YSYN) on multi-infarct dementia (MID) rats and its mechanism. Method: The multi-infarct dementia model

were induced by injecting compound thrombosis inducer into the external carotid artery.Sixty SD rats were randomly divided into model group

YSYN high dose group (960 mg·kg-1)

middle dose group (480 mg·kg-1)

low dose group 240 mg·kg-1

western medicine positive group (Ebixa

0.5 mg·kg-1)

YSYN+Ebixa group (480 mg·kg-1+ 0.5 mg·kg-1)

sham operation group.From 3 days after modeling

corresponding drugs were given once daily

lasting four weeks. The Morris water maze was used to test the abilities of learning-memory

enzyme-linked immunsorbent was used to assay the levels of norepinephrine(NE) of hippocampal tissue

and chemocolorimetry was used to assay the levels of acetylcholinesterase (AchE)

cholinacetyltrans-ferase(CHAT)

glutathione peroxidase (GSH-Px). Result: Compared with sham operation group

learning memory abilities of model group rats were significantly decreased (P<0.05

P<0.01)

the content of AchE significantly rose (P<0.05) and CHAT and GSH-Px significantly decreased. Compared with model group

the YSYN could significantly improve the abilities of learning memory in MID rats(P<0.05);decreased the level of AchE increased the level of CHAT

NE and GSH-Px (P<0.05

P<0.01). Conclusion: The YSYN could significantly improve the abilities of learning memory in MID rats

and has a good protective effect on MID rats. Its mechanism may adjust the level of NE

AchE

CHAT and GSH-Px of hippocampus tissue.