Dynamic expression of corticotropin-releasing hormone and urocortin in estrogen induced-cholestasis pregnant rat.

Intrahepatic cholestasis of pregnancy(ICP) is complicated by acute placental-fetal hypoxia. Corticotropin-releasing hormone(CRH) and urocortin(UCN) are vasodilatory regulators of blood flow in the placenta. An ethinylestradiol(EE)-induced cholestasis rat model was reproduced and serum/placental CRH/UCN were detected during 14-21days of gestation(DG). Maternal serum or placental CRH/UCN levels in the control rats were relatively consistent during 14-21DG. Serum CRH was reduced in the EE-treated rats compared with the control rats at 21DG. Regarding serum UCN, we observed a decrease at 17DG as well as an increase at 21DG in the EE-treated rats compared with the controls. Moreover, we observed a noticeable reduction of placental CRH/UCN expression at 17 or 19DG in the EE-treated rats compared with the control rats. The serum bile acids levels exhibited an inverse correlation with placental CRH/UCN expression. EE-induced cholestasis rats might serve as a good model to further investigate the pathological mechanism underlying CRH/UCN dysregulation in ICP.