Is prostacyclin a major prostaglandin produced by endothelial cells in culture?

Prostaglandin biosynthetic activity of cultured human aortic and umbilical vein endothelial cells (passages 3-9) and of human aortic subendothelial cells (passage 0) was studied. Labelled arachidonic acid or endoperoxide H2 (final concentrations, 10 microM and 3.5 microM, respectively) were used as prostaglandin synthesis precursors. Arachidonic acid metabolites released into the incubation medium were separated by thin-layer chromatography and assayed for radioactivity. It has been demonstrated that endothelial and subendothelial cells in culture synthesize, besides prostacyclin, significant quantities of other prostaglandins, such as PGF2, PGE2, as well as thromboxane B2.