As several plants have anticoagulant activity, Calotropis procera has been investigated "in vitro" in this study. Hot and cold water, ethanol, and methanol extracts of these plant leaves were prepared to final concentrations of 100, 50, and 25 mg/ml. In vitro, PT and aPTT assays were conducted on normal platelet poor plasma blood samples of 20 healthy volunteers by a digital coagulation analyzer. Results showed that all evaluated extracts prolonged both PT and aPTT at 100 and 50 mg/ml concentrations. The highest effect on PT was observed for ethanol and methanol extracts by recording 128.52±24.45 sec and 105.99±17.76 sec at 100mg/ml concentrations, respectively. The high effect on aPTT was observed for all evaluated extracts by recording 420 ±0.00 sec at 100mg/ml concentration. So they could have an inhibitory effect on the clotting factors in the intrinsic and extrinsic pathways and those in the common pathway. While at 25 mg/ml concentrations, they prolonged PT only, 16.63±1.78 sec, 15.34±0.97 sec, 16.19±1.32 sec, and 16.02±1.37 sec for hot water extract, cold water extract, ethanol extract, and methanol extract, respectively. Suggesting their inhibitory effect was on the extrinsic pathway tissue clotting factors. On the contrary, they demonstrated a decreasing effect on aPTT at a concentration of 25 mg/ml, recording zero aPTT, affecting the intrinsic pathway. Moreover, compared with the positive heparin control, only the alcoholic extracts at 100 mg/ml concentration showed a similar anticoagulant effect on PT (P>0.05). While all evaluated plant extracts at a concentration of 100 mg/ml revealed similar bioactivity on aPTT (P>0.05). Still, all evaluated extracts' anticoagulant and procoagulant activity need in vivo clarification.

Digital Object Identifier (DOI)