THE STUDY OF ETIOLOGY AND PATHOPHYSIOLOGY OF PREECLAMPSIA,ANALYSIS IN THE ASPECT OF INTRACELLULAR SIGNAL TRANSDUCTION

1. 内皮细胞功能：重度妊高伴孕高血压（severe PIH）孕妇血浆内皮素-1水平高于正常对照组。严重PIH患者的脂肪代谢变化如下：高甘油三酯血症伴低高密度脂蛋白胆固醇血症，血浆饱和/不饱和脂肪酸比值升高，血浆过氧化脂质浓度升高，血浆维生素e水平降低，这些被认为是引发和/或恶化内皮细胞功能障碍的因素。体外培养内皮细胞的研究也表明，严重PIH患者性类固醇和脂质谱的改变与该疾病的病理生理有关。然而，严重的PIH患者血浆中血小板活化因子浓度升高，具有血管舒张作用，提示内皮可能仍具有对抗高血压的功能。Western blot结果显示，正常妊娠和重度妊高征胎盘组织组成型一氧化氮合酶含量相等。虽然病例数较少，但重度PIH.2患者有尿中一氧化氮代谢物排泄减少的趋势。电解质代谢：严重PIH患者全血离子化镁浓度和细胞内镁浓度明显低于正常对照组，而两组间血清Mg水平无显著差异。提示重度PIH患者存在Mg代谢改变。MgSO4加载结果显示，该疾病中Mg相对缺乏。胎儿发育：血浆IGF-1水平在正常妊娠过程中升高，与胎儿发育和母亲体重增加有关。在严重妊高征中，尽管母体体重增加，血浆IGF-1浓度极低。这表明IGF-1的变化反映了与胎儿生长密切相关的母体营养状况的紊乱。少

1. Endothelial cell function : Pregnant women complicated with pregnancy-induced hypertension in severe type (severe PIH) showed increased plasma levels of endothelin-1 than did normal controls. Changes in fat metabolism were also observed in severe PIH as follows ; higher triglyceridemia with lower HDL-cholesterolemia, increased plasma saturated/unsaturated fatty acids ratio, increased plasma concentration of lipid-peroxide and decreased levels of plasma vitamin E.These are considered as factors intiating and/or deteriorating endothelial cell dysfunction. In vitro studies using cultured endothelial cells also demonstrated that altered profiles of sex steroids and that of lipids in the severe PIH are involved in the pathophysiology of the disorder. However, severe PIH patients also showed increased plasma concentration of platelet-activating factor, which has vasodilatory effect, suggesting that endothelium may still function to antagonize high blood pressure. Nitric oxide synthase of … More placental tissue in constitutive type was demonstrated to be equal on Western blot between normal pregnancy and severe PIH.Although the number of cases is small, there was a tendency of decreased urinary excretion of metabolites of nitric oxide in severe PIH.2. Electrolytes metabolism : Concentrations of ionized Mgin whole blood and these of intracellular Mg were significantly lower in severe PIH than in normal controls, while there was no significant difference in serum Mg levels between the two groups. These suggest altered Mg metabolism exist in severe PIH.The results of MgSO4 loading revealed a relative deficiency in Mg in the disorder.3. Fetal development : Plasma IGF-1 levels increased along the course of normal pregnancy correlating to fetal development and maternal weight gain. In severe PIH plasma concentrations of IGF-1 was extremely low in spite of maternal weight gain. This suggests change in IGF-1 reflects disorders in maternal circumstances in nutrition which is closely related to fetal growth. Less