[PGI2-like activity of the internal mammary artery and the saphenous vein used in coronary bypass surgery].

: The best graft in coronary bypass operations is the internal mammary artery as its rate of staying open for long term is better than that of saphenous vein. The prostacyclin-producing capacity of these human blood vessels was studied using platelet aggregation bioassay. The synthesis of prostacyclin-analogous was significant higher in internal mammary artery than that was in saphenous vein (in 10 min of incubation time internal mammary artery: 73.33; saphenous vein: 42.27 pg/mg). Based on our results we conclude that the difference of "prostacyclin-like" activity between artery and vein might play a role, at least partly, in the more successful operations performed with internal mammary artery.