The effects of continuous infusions of prostacyclin-Na (epoprostenol-sodium) on platelet counts, ADP-induced aggregation, and cyclic AMP levels in normal volunteers

Six male volunteers received either 0 (buffer), 2.5 or 5.0 ng/kg/min PGI2·Na for 72 hrs. Various platelet parameters were monitored for an additional 72 hrs. Each morning, for seven consecutive days, and +1 and +6 hrs after the termination of the infusion, blood was drawn and platelet rich plasma (PRP) was prepared. The PRP was immediately exposed to 100 ng/ml PGI2·Na, and the subsequent increase in platelet cyclic AMP was measured by radioimmunoassay. Aggregation in response to 2 or 4 μM ADP was measured simultaneously.