Abstract: Objective：To investigate the expression and significance of organic anion transporting polypeptides 4A1（OATP4A1），OATP2B1 in placenta of intrahepatic cholestasis of pregnancy（ICP）. Methods：Twenty pregnant women with ICP were recruited and twenty normal cesarean section patients as control groups. The expression of mRNA was analyzed by real-time PCR. Data were analyzed by the comparative threshold cycle（CT） method and the 2-△CT method was used（△CT=CT gene of interest -CT internal control）. Results：The expression of OATP4A1 mRNA was higher（P＜0.05） and OATP2B1 was significantly lower（P＜0.01） in ICP placenta than in normal placenta. Significantly elevated cholylglycine（CG）′s level of fetal and maternal serum was associated with ICP. Conclusions：The data presented here suggests that up-regulation of transporter OATP4A1 may involve in the pathophysiology of ICP，which cause the disorder of bile acids. The expression of OATP2B1 in placenta was down-regulation in ICP. It may be involved in the disorder of estrogen metabolism in ICP，causing the mother continued high levels of estrogen stimulation and changed sensitivity.

Key words: Cholestasis, intrahepatic, Cesarean section, Polymerase chain reaction, RNA, messenger, Estrogens, Glycocholic acid