血小板激活因子对人胎盘绒毛及脐动脉血栓素A_2、前列腺素I_2生物合成的影响

The Effect of Platelet Activating Factor on the Biosynthesis of Thromboxane A 2 and Prostaglandin I 2 in Human Placental Villi and Umbilical Artery

目的：探讨血小板激活因子（ＰＡＦ）对人胎盘绒毛及脐动脉血栓素Ａ２（ＴＸＡ２）及前列腺素Ｉ２（ＰＧＩ２）生物合成的影响。方法：采用组织滴注法及放射免疫分析法，检测ＰＡＦ（１０－９～１０－７ｍｏｌ／Ｌ）滴注于人胎盘绒毛及脐动脉后，滴注液中血栓素Ｂ２（ＴＸＢ２）及６－酮前列腺素Ｆ１α（６－ｋｅｔｏ－ＰＧＦ１α）含量的变化。结果：ＰＡＦ在一定浓度下可刺激人脐动脉ＰＧＩ２及胎盘绒毛组织ＴＸＡ２的合成。ＰＡＦ在１０－９ｍｏｌ／Ｌ浓度时对胎盘绒毛ＴＸＡ２的作用最大，使ＴＸＢ２的含量由６３．１５±１３．２４ｐｇ／ｍｇ蛋白增加到１２７．０３±２７．７６ｐｇ／ｍｇ蛋白（Ｐ＜０．０１）。ＰＡＦ对脐动脉ＰＧＩ２的最大刺激浓度为１０－８ｍｏｌ／Ｌ，使６－ｋｅｔｏ－ＰＧＦ１α的合成量由６７４７．５２±７００．３１ｐｇ／ｃｍ增加到８３４２±３３５．８１ｐｇ／ｃｍ（Ｐ＜０．０１）。结论：ＰＡＦ可能通过调节局部ＰＧＩ２和ＴＸＡ２的水平，影响胎儿－胎盘的血液循环。

Objective: To evaluate the effects of platelet activating factor (PAF) on the biosynthesis of thromboxane A 2 (TXA 2) and prostaglandin I 2 (PGI 2) in human chorionic villi and umbilical arteries. Methods: We perfused the human placental villi and umbilical arteries with PAF (10 -9 ￣10 -7 mol/L), then quantified TXB 2 and 6 keto PGF1α in the perfusion fluid by Radioimmunoassay. Results: PAF stimulated the biosynthesis of TXA 2 and PGI 2 in human umbilical ateries and chorionic villi in vitro. The production of TXB 2 increased from 63.15±13.24 pg/mg protein to 127.03±27.76 pg/mg protein with response to the stimulation of PAF (10 -9 mol/L) ( P <0.01). The concentration of PAF (10 -8 mol/L) displayed the most optimal stimulating effect on PGI 2 biosynthesis in umbilical artery samples and the production of 6 keto PGF1α increased from 6 747.52±700.31 pg/cm to 8 342±335.81 pg/cm ( P <0.01). Conclusion: PAF may affect the fetal placental circulation by regulating the local levels of PGI 2 and TXA 2.