Figure 6.

Comparison of the anti-aggregatory potencies of prostacyclin (PGX) and PGE₁. PGX was obtained by incubation of 100 ng PGH₂ with 500 μg of aortic microsomes in 100 μl of 0.05 M Tris buffer for 2 min at 22 °C and then stored on ice. PGX and PGE₁ were added to human platelet-rich plasma 1 min before the platelets were aggregated with arachidonic acid (AA, 1 mM). In this experiment, PGX is at least 25 times more potent as an anti-aggregating agent than PGE₁. Reprinted, with permission, from Moncada et al. (1976a).