Pii: 0049-3848(90)90271-d

Prostacyclin release from endothelial cells in culture appears increased by the presence of plasma, but occurrence of a similar phenomenon in intact vessels has not been established. In the present investigation release of 6-keto-PGF quantitated from &i the stable breakdown product of prostacyclin, was ne veins perfused ex vivo for 15 minute periods, using three different perfusates: 1) Hank’s balanced salt solution (I-IBSS), 2) 20% in HBSS, and 3) ! latelet poor lasma (PPP derived from heparinized blood, 0% PPP in H Y3 SS with ad d’ ed arachidonic acrd (AA). No differences in initial 6-keto-PGF release existed among the three perfusates. However, PPP and PPP + ,& solutions were associated with lesser declines in release, than occurred with HBSS alone, these differences bein statistically significant after 60 ruin of perfusion (p ~0.05). When PP ! derived from heparinized and titrated blood rather than from only heparinized blood was used, there was a significantly lower release of prostaEli” 9 ~0.05). The latter may be due to citrate binding of calcium. ese ata indicate that autologous plasma does not alter mitial prostax clin release from freshly harvested canine veins, but that it weakens t e decline in release usually following prolonged periods of perfusion.