The Effects of Prostacyclin on the Coagulation of Whole Blood

Summary

The effects of prostacyclin (PGI₂) on mechanical properties of forming clots were investigated by testing human blood samples on a Thrombelastograph. Concentrations greater than 50 ng/ml (blood) caused a biphasic development of clot stiffness. During the first phase, PGI₂ partially inhibited the platelet involvement in coagulation causing initial clot formation at a normal time but with reduced clot stiffness. The second phase occurred after neutralization of PGI₂ activity and was characterized by recovery of platelet activity to produce a final clot with normal shear modulus. The duration of the inhibitory effects depended on PGI₂ concentration and hematocrit. With a normal hematocrit, a PGI₂ concentration of 60 ng/ml caused an inhibition for about 40 min whereas a concentration of 100 ng/ml caused inhibition for about 75 min.

Keywords

Prostacyclin - Platelet - Thrombelastography

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