Objective: To investigate effects of total flavonoid fraction of Asttragalus complanatus on blood pressure in conscious spontaneously hypertensive rats(SHR) and hemodynamics in anesthetized SHR.
Method: Blood pressure was recorded with tail-culf method and hemodynamics was recorded with polygraph after administration of total flavonoid fraction of Asttragalus complanatus.
Result: Total flavonoid fraction of Asttragalus complanatus (100, 200 mg.kg-1) could decrease blood pressure of conscious SHR(decreasing 7.1%, P < 0.05 and 9.3%, P < 0.01 respectively). Meanwhile, there was no significant change in heart rate(HR). R Br (200 mg.kg-1) could decrease total peripheral resistance (TPR) (decreasing 20%, P < 0.05) but did not influence the cardiac output(CO) and heart rate in anesthetized SHR.
Conclusion: Total flavonoid fraction of Asttragalus complanatus possesses obvious hypotensive effect, mainly by means of decreasing the TPR.