Objective: To study the active components in Angelicae Dahuricae Radix with activating blood circulation effect. Method: The different extracts from Angelicae Dahurica Radix were obtained by the means of systematic solvent extraction.Rats were randomly divided into 7 groups:control group

model group

positive control group (aspirin 12 mg·kg-1) and petroleum ether

ethyl acetate

butanol

water extract group(20 g·kg-1 equivalent to the primary drug).The drugs were ig given for 7 days

once each day. 1 h after the last administration

the rats were injected with 0.1% epinephrine 0.8 mg·kg-1 with 2 times and 4 h interval to establish the blood stasis model.Then the activating blood circulation activity was studied by hemorheology test. The HPLC fingerprints of 10 different areas of the most active extracts from Angelicae Dahurica Radix were established and the activating blood circulation activity of 10 batches was detected.The spectrum-activity relationship of the extracts was studied by mathematical statistics method. Result: Compared with the normal group

the whole blood viscosity

plasma viscosity

hematocrit

erythrocyte aggregation index were significantly increased in model group(P<0.01). Compared with the model group

the hemorrheological indexes in the groups of different extracts of Angelicae Dahurica Radix were improved(P<0.05-P<0.01). The Ethyl acetate extracts had the best activating blood circulation effect (P<0.01).The spectrum-activity relationship of the extracts was found that peaks 4

9

11

12，16 of the extracts had the stronger activating blood circulation effect. Conclusion: Common peaks 4

9

11

12，16 could be characteristic peak for activating blood circulation activity of Angelicae Dahurica Radix. The spectrum-activity relationship of Angelicae Dahurica Radix established could provide the theoretical basis.