Abstract: The goal of this research was to screen of effective parts in Rubiae radix et rhizome Carbonisatum with resisting coagulation tendency.The acute blood stasis model in rats were established with subcutaneous injection of high-dose adrenaline hydrochloride and being socked in ice-water,using Yunnan Baiyao powder as positive drug.The effect of different polar fractions on hemorheology,external thrombus,blood plotelets system and fibrinolytic system in acute blood stasis model rats were observed.The results showed that the n-butanol fraction had the highest effect in resisting coagulation tendency which both significantly decreased the whole blood viscosity in medium and low shear rate,the wet weight and dry weight of external thrombus,significantly decreased the content of PAI-1 and TXB-2,increased the t-PA and the 6-keto-PGF-1α content (P<0.05 or P<0.01).The effect of resisting coagulation tendency in other polar parts were lower than that of n-butanol fraction.Hence,the n-butanol fraction were the effective fractions in resisting coagulation tendency.

Key words: Rubiae radix et rhizome Carbonisatum, resisting coagulation tendency, fraction screening, acute blood stasis model