研究不同浓度胆酸(cholalic acid，CA)、胆红素(bilirubin，BLB)/胆酸对离体(in vitro)脐动脉血管环的收缩作用，探索妊娠期肝内胆汁淤积症(intrahepatic cholestasis of pregnancy，ICP)患者胎儿宫内窘迫、突发胎死宫内等并发症的可能机制。

选择2003年9月至2003年12月在华中科技大学同济医学院附属协和医院妇产科住院分娩、既往健康，无妊娠合并症及并发症孕妇24例为研究对象。分娩后即取脐带(胆酸组，n＝24；胆红素/胆酸组，n＝24)(本研究遵循程序符合华中科技大学同济医学院附属协和医院人体试验委员会所制定的伦理学标准，得到该委员会批准，取得受试对象知情同意，并与之签署临床研究知情同意书), 采用4道生理记录仪测定其脐动脉血管环在不同浓度胆酸、胆红素/胆酸刺激下的收缩张力值，分析脐动脉血管环收缩功能改变与胆酸、胆红素/胆酸浓度的相关性。

相同浓度下，胆红素/胆酸对脐动脉血管环的收缩张力升高作用较胆酸组强，两组比较，差异有显著意义(P<0.001)。5种不同浓度胆酸作用下，脐动脉血管环的收缩张力值(mg)分别为22.13±12.05，42.04±18.35，73.88±32.92，112.63±48.90，154.54±52.07; 相应浓度的胆红素/胆酸对脐动脉血管环的收缩张力值(mg)分别为35.29±13.31，68.63±25.13，116.00±42.8，168.29±49.11，且脐动脉血管环的收缩张力值与胆酸、胆红素/胆酸的浓度有很好的相关性(r＝0.794，0.818)。

不同浓度胆酸可刺激脐动脉血管环收缩，呈剂量依赖性关系。胆红素可协同胆酸刺激脐动脉血管环收缩。高浓度胆酸、胆红素/胆酸对脐动脉的刺激收缩作用，为妊娠期肝内胆汁淤积症患者胎儿宫内窘迫、突发胎死宫内、新生儿窒息及早产、死产等并发症的重要原因。

To investigate contractile effects of various concentration of cholic acid and bilirubin/cholic acid in vitro on umbilical arterial circle, and study the mechanism of fetal distress and fetal death in uterus of gravida with intrahepatic cholestasis of pregnancy.

From September 2003 to October 2003, 24 cases who were admitted to the department of Obstetrics of the Union Hospital affiliated to TongJi University to delivery. All of them were healthy and without pregnant complications. The umbicial cords were taken as the investigative objects. The procedure of the study following is according to ethical criterion which made by the somatological test committee of the Union Hospital affiliated to TongJi University receiving the sanction of the committee and the agreement of the patients. Informed consent was obtained from all paticipates. The contractile values of umbilical arterial circle by the stimulation of cholic acid and bilirubin/cholic acid (cholic acid group, n=24; bilirubin/cholic acid group, n=24) were recorded. The correlation between umbilical arterial circle's contraction and concentration of cholic acid and bilirubin/cholic acid were analyzed.

With the certain concentration, the contractile values of cholic acid on umbilical arterial circle were (22.13±12.05) mg, (42.04±18.35) mg, (73.88±32.92) mg, (112.63±48.90) mg, (154.54±52.07) mg, while the contractile values of bilirubin/cholic acid on umbilical arterial circle were (35.29±13.31) mg, (68.63±25.13) mg, (116.00±42.8) mg, (168.29±49.11) mg, respectively.

Various concentration of cholic acid can stimulate the umbilical arterial circle to shrink with a pattern of dose-dependent. Bilirubin/cholic acid have synergistic action to it. The contractile effect of umbilical arterial circle by high concentration of cholic acid and bilirubin may be an important cause of fetal distress and fetal death in uterus of gravida with intrahepatic cholestasis of pregnancy.