The Effect of Platelet Activating Factor and Tumor Necrosis Factor on the Synthesis of Prostaglandin E2 from Human Amnion Cells

Chung, Jae Hyun; Kim, Syng Wook

Abstract

To investigate the properties and mechanism of PAF and TNF on the synthesis of prostaglandin E2 in human amnion, primary monolayer culture method was used for human amnion cell incubation. Amnion cells were incubated with various concentrations of PAF or TNF in Ca++ containing medium for various duration. Then PG E2 concentrations were measured by RIA and analyzed for the effect of PAF and TNF on PG E2 production according to their doses and incubation time. To test the role of Ca++ in E2 production, Ca++ free medium, Ca++ -channel antagonist and cyclo-oxygenase inhibitor were substituted or added in incubation medium. Following results were obtained. The synthesis of PG E2 was significantly enhanced by PAF of 10(-6) mol/L. The TNF also stimulated PG E2 synthesis at concentration of 10(-6)g/ml. The maximal level in PAF(10-6mol/L)-stimulated release of PG E2 was observed after 16 hours in incubation. The TNF(10(-6)g/ml)-induced PG E2 release was maximal after 24 hours of incubation. Combined application of PAF and TNF produced positive effect in PG E2 production. PAF or TNF stimulated-PG E2 production in Ca++ -free media was much lower than that of Ca++ -containing media. The PAF-stimulated PG E2 release was significantly inhibited by Ca++ -channel antagonist but TNF-stimulated PG E2 release was not effected by Ca++ -channel antagonist or cyclo-oxygenase inhibitor. It is strongly suggested us that both PAF and TNF enhance PG E2 release by amnion cell, although Ca++ -channel opening is essential only for PAF stimulation.