The Mechanism Of Farnesoid X Receptor And Bile Salt Export Bump On Bile Acid Transport In The Placenta Of Intrahepatic Cholestasis Of Pregnancy

OBJECTIVE To explore the pathogenesis of intrahepatic cholestasis of pregnancy(ICP) and the effect on bile acid transport in the placenta of ICP by detecting the level of glycocholic acid(CG) in mother blood, umbilical venous blood, and the expression of farnesoid X receptor(FXR) and bile salt export bump(BSEP) in placenta.METHODS CG levels in 30 cases of ICP were detected in mother blood and umbilical venous blood by radioimmunoassay and hepatic function (tranaminase, total bile acid)was also detected, 30 cases of normal pregnancy as compared group were also tested.The expression of FXR and BSEP in placenta were detected in both groups by immunohistochemistry and image analyse. RESULTS (1)The CG levels in mother blood and umbilical venous blood in ICP were higher than that of normal pregnancy(p<0.05); The CG level in mother blood was related umbilical venous blood in ICP, but the CG level in umbilical venous blood was lower than in mother blood .There was no difference in normal pregnancy(p>0.05).(2)The levels of CG was not related with meconium staining,fetal weight,Apgar score ,S/D ratio of umbilical artery and gestational age(p>0.05). (3) The expression of FXR in placenta was founded, which was more in ICP than in normal late pregnancy(p<0.05). (4) The expression of BSEP in placenta was positive in normal pregnancy, negative in ICP.CONCLUSION (1) The CG level in mother blood and umbilical venous blood in ICP was higher than that of normal pregnancy, whose relationship with fetal prognosis was not tested. (2)There might be positive transport of bile acid against concentration in placenta. (3)The positive transport of bile acid against concentration in placenta might be effected in ICP.(4)The abnormal expression of FXR and BSEP in placenta resulting in transportation changes of bile acid may be one of the mechanisms of ICP.