Demonstration of PGI2 production by isolated perfused rat lungs with platelet aggregation test.

Platelet aggregation test was used for PGI2 measurements. The use of 6 % CO2 in air stabilized human platelet rich plasma (PRP) so that it could be used for up to 7 hours in these measurements. The PGI2 caused inhibition of aggregation in response to ADP was concentration dependent in the range of 0.5 ng/ml to 50 ng/ml. Isolated perfused rat lungs released spontaneously 190 ng/min PGI2 and about 3 % of infused arachidonic acid potassium salt (equivalent to 25 microgram/min arachidonic acid) was converted to PGI2.