[Experimental studies on platelet preservation with prostaglandin I2 and its derivative (OP-41483) during cardiopulmonary bypass]

Platelet number and its function, specially of aggregability, the changes of intrinsic vasoactive prostanoids were studied in experimental cardiopulmonary bypass (CPB) with PGI2 and its derivative, OP-41483 (OP). Twenty mongrel dogs were divided into the following 4 groups; control group (noCPB, C), heparin group (heparin 2 mg/Kg, H), PGI2 group (heparin 2 mg/Kg + PGI2(1) ng/Kg/min, PG) OP-41483 group (heparin 2 mg/Kg + OP-41483 1 ng/Kg/min, OP). CPB was carried out for 2 hours by roller pump through a membrane oxygenator. The following results were obtained. 1. The drop of mean arterial pressure during CPB with OP was not shown at this dosage. 2. Platelet counts during CPB were well maintained by both PGI2 and OP infusions. 3. The recovery of platelet aggregability examined by 2 microM ADP and whole blood aggregometer induced by collagen with OP were superior to that with PGI2. 4. In spite of PGI2 or OP infusion, no remarkable improvements of intrinsic PGI2 production and TXA2 inhibition were observed. In conclusion, the PGI2 and OP infusion, especially OP during CPB, could well preserve platelet functions and this experimental study might indicate the possibility of the clinical application of these drugs, for the prevention of postoperative hemorrhage.