Objective: To investigatet the time-effect and dose-effect of anti-hypertensive effect in spontaneously hypertensive rats (SHR) byaqueous extract and the supernatants of alcohol extracting-water precipitation of Prunella vulgaris L. Method: P. vulgaris was processed by water extraction

water extraction and alcohol precipitation.The SHR were treated with different dose of two extracts. SBP

diastolic blood pressure(DBP)

mean arterial pressure(MAP)

and heart rate(HR) were measured before and after oral administration for 2

5

7

10 h for determining the time-effect. Result: Compared with the model group

no significant effect were showed on MAP and HR of SHR in all the different dose of test group in every test time points. SBP of SHR decreased significantly in aqueous extract(10

5 g·kg-1) and the supernatants of alcohol extracting-water precipitation(10

5

2.5 g·kg-1) of P. vulgaris

while high dose (10 g·kg-1)of the supernatants of alcohol extracting-water precipitation decreased DBP of SHR after oral administration for 5 h(P<0.05). Conclusion: The supernatants of alcohol extracting-water precipitation of P. vulgaris retain and enrich the active anti-hypertension principles when parts of other principles were removed

which can provide reference for the study of anti-hypertension material base and pharmaceutical technology in P.vulgaris.