[Role of prostacyclin in the antiaggregation activity of the vascular wall].

A comparative study was made of the changes in the anti-aggregate effect of crystalline prostacyclin and substances secreted by vascular segment after incubation in platelet rich plasma. The anti aggregate effect of the vascular wall was shown to be determined not only by prostacyclin but also by a number of other substances that differ from the latter in the effect pattern on platelets and stability in plasma. Evidence is provided in favour of the fact that the basal level of anti-aggregate activity of the vascular wall and its changes induced by different factors depend on the pro-/anti-aggregate ratio in a complex of agents released into plasma by the vascular wall.