The Role Of Syncytiotrophoblast Microvillous Membrane In Pre-eclampsia

Background and goals:Pregnancy-induced hypertension is a idiopathic disease in The Obstetrics. It occurs in5%-8%of normal pregnancy, makes the fatality rate nearly10%-16%in all. Through manyscientists’ efforts of decades, now it etiology still is unkown, but there are a hugeimprovement in “vascular endothelial injury theory”.two pathophysiological stage—1.disturbed placental function in early pregnancy include Impaired trophoblast invasion andremodelling of the spiral artery.2. The toxic factor shed from placenta damage vascularendothelial, enhanced maternal intravascular systemic inflammatory response includehypertension, proteinuria, hypercoagulable state. The toxic factors release from placentaplay a key role in the etiology of PE.Now some scientists assume PE is a placental disease.Normal third trimester pregnant women has a hyper-coagulation, APTT、PT wereshortened, FIB was elevated, it prevent women from haemorrhage. PE have a higherhypercoagulable state than normal pregnant women,endogenous coagulable pathway,as theexogenous coagulable pathway, be activated. APTT、PT were both dramatic shortened. Infirst trimester, PE appear hypercoagulable state, it earlier than any clinical features andother laboratory index. HELLP is a serious complication of PE. It has PLT＜50×109/L、elevated enzyme of liver、hemolysis, it’s a serious type of PE induce coagulable state.Although there are many evidences to identify the hyper-coagulable state of PE, there haveno research about the mechanism of PE’s hyper-coagulable state. There have a commonview: the increase of TAT, factorⅧ， von Willebrand factor, D-Dimer, soluble fibrin,thrombomodulin. Activated protein C has a resistence. Antithrombin-Ⅲ, platelet aredecrease in PE. But all of that can’t explain the reason of PE’shypercoagulable state.Syncytiotrophoblast microvillous membrane (STBM) is a made of membranesmicro-particles, which have many Syncytiotrophoblast cytoplasm and materials. STBMplay carriers between maternal and fetal, which adjust by the activated or apotosis Syncytiotrophoblast. And many research verified more STBM are released in PE, especiallyin early-onset PE. In vitro, STBM can induce PE’s pathological changes in many sides:1.Impaire the endothelial cell growth and functions,2.take part in the modulation of immunethrough NK、TC and inflammatory factors. Up to now there is no paper to investigate thatthe STBM effect the coagulation in PE.MPs from platelet can offer a membrane surface toinitiated tissue factor (TF) pathway. According the fact of elevated STBM andhyper-coagulable state of PE, we presume that STBM play some role in the PE’shyper-coagulable state.The goal of this study is to find out the initiated pathway in PE, todiscuss the unusual increased STBM in PE play a important role of the initiated ofcoagulant materials.Materials and methods:1.The coagulation index and platelet markers of PE①Subjects and groupingPregnant women have a systemic checkout in the third hospital of The Third MilitaryMedical University. There are24of mild PE, and19severe PE, others are healthpregnancy.②collection of bloodWe use the vacuum blood tube with EDTA/sodium citrate to collect blood, centrifugeto get the blood plasma.③simples detectionWe are loading the blood simples into the automatic instrument to detect the indexes in2hours.④data analysisWe use the software of Excel and SPSS to deal with the data.2. Elevated STBM effect the function of coagulation in the pregnant mouse.①Preparation of STBMIn a asepsis condition, we get the placenta from pregnant C57BL/6mouse(17days),according to the paper to prepare STBM. We detection the total amount of STBM’s proteinsand identify STBM with electric-microscope.②Grouping: we have5groups, inject with PBS(P-CTL)、low concentration of STBMin pregnant mouse(P-S-L)、middle concentration of STBM in pregnant mouse (P-S-M)、 high concentration of STBM in pregnant mouse (P-S-H)、high concentration of STBM+herpin in pregnant mouse (P-S-H+heprin)；middle concentration of STBM in non-pregnantmouse (NP-S-M). Every group has injected0.2ml liquid from10th-17thdays, except forP-S-H and P-S-H+heprin from17thday.③Collection the blood and organsNarcotized mouse who was injected7days was collect blood from eyes, centrifugeblood to get serum store in-20°C. We move the brain and lung, in a tube withparaformaldehyde.24hour later, the organs to make paraffin blocks.④Detection of the coagulant index with auto-machine (APTT、PT、D-D).⑤Detection of the coagulant materials with kit of ELISANumbered the blood samples, detect “TAT, APC,AT-III,TM,TF/TFPI” with ELISA kit.⑥Make pathological sections of mouse’brain and lungUse the paraffin blocks to chip as a6mm pathological sections, dye HE, observe underthe microscope and take photos.Result:1.The changes of coagulation index in different trimester of PE.The third trimester has more decrease of FIB(P <0.05)、APTT (P <0.05)than the firsttrimester in all groups. Severe pre-eclampsia group has longer TT than in the control group(P <0.05).D-D are also much higher in the sPE group. PT has less change. All groups in thethird trimester appears much account of PLT, bigger MPV than the first trimester (P <0.05),but not in the PDW、PCT.2.STBM effect the function of coagulation in mouse.The STBM was detected by the BCA kit, total protein amount are between the0.52mg/ml and1.22mg/ml，the average is (0.73±0.10)mg/ml. We use the electric-microscope toobserve the micro-particles which the diameter are between200-500nm, the littlemicro-vesicles cluster round together.1) The change of coagulation index in mouseCompared with the control group, P-S-H has a shorten time of APTT、PT (P <0.05),D-D has less change. P-S-L has little difference against NP-S-L group.2) The variational materials and functions of coagulation in mouse.TAT、APC、TF、TFPI are increased are accompanied with increase amount of STBM. In P-S-M group and NP-S-M group, there are higher TF/TFPI than others (P <0.05). Thereis no variety in P-S-L group. Compared with P-CTL and P-S-H+heprin group,P-S-H’splasma appear high TAT and APC (P <0.05). P-S-M group has no change with NP-S-Mgroup.3) Thrombus is founded in the mouse’s HE pathological sections.Compared with P-CTL group, P-S-H group’s HE pathological sections of brain andlung are both founded Thrombus. It seem like homogeneous red structure, which filled withthe lumen of vessel. We consider it’s hyaline thrombus.Conclusion:1. The increase of STBM shed from PE’s peripheral blood can activated coagulationand fibrin system. Especially in sPE, TT has prolonged、D-D has elevated. It all verify PEappear a hyper-coagulable state.2. With the increase of STBM, APTT、PT are shorted, TF/TFPI are elevated in mouse’speripheral blood. It is an evidence to the activeted exogenous coagulable pathway like PE’s.3. STBM can induce PE’s symptom in mouse, who’s TAT and APC are increased inperipheral blood, it indicate that TAT、APC play a significant role in initiated PE’shyper-coagulable state.