Effects of Thromboxane Synthase Inhibition on Placental Prostacyclin and Thromboxane Production

Abstract

Selective inhibition of thromboxane synthesis without affecting prostacyclin synthesis is being considered as a potential treatment for preeclampsia because of its imbalance of increased thromboxane/decreased prostacyclin production. Thromboxane production by the placenta is greatly increased in preeclampsia so effective therapy must inhibit placental, as well as maternal platelet, thromboxane production. The following study was done to evaluate the production rates of thromboxane and prostacyclin in placental tissues incubated with and without the throraboxane synthase inhibitor, U-63,557A. Fresh, human term placental tissues (350 mg) were incubated in a sterile manner in 7 ml Dulbecco's Modified Eagle's Medium for 48 hours at 37°C with 95% oxygen and 5% carbon dioxide in a metabolic shaker. Samples were collected at 0, 8, 20, 32 and 48 hours and analyzed for thromboxane A2 by radioimmunoassay of its stable metabolite, thromboxane B2, and for prostacyclin by radioimmunoassay of its stable metabolite, 6-k...