Effect of an extract of Paeonia lactiflora on the blood coagulative and fibrinolytic enzymes

Paeonia lactiflora with the action of promoting blood circulation and removing blood stasis had been shown to be able to inhibit thrombosis and platelet aggregation, increase fibrinolytic activity and promote thrombolysis. This paper described the influence of the extract of Paeonia lactiflora in vitro experiments on prothrombin time (PT), activated partial thromboplastin time (PTT), antithrombin effect, activity of plasminogen and urokinase. The experimental results showed that: (1) The extract of Paeonia lactiflora prolonged the time of PT and PTT. (2) The extract of drug was able significantly to inhibit the thrombin. (3) In study of fibrinolysis by fibrin standard plate experiments, the drug possessed activative effect on the plasminogen. (4) The activity of urokinase was reduced, while the extract of Paeonia lactiflora existed. The inhibitory effect on thrombin and effective effect on plasminogen of the drug might be an important mechanism of its action of promoting blood circulation and removing blood stasis.