Characterisation of the nuclear receptors FXR, PXR and CAR in normal and cholestatic placenta.

Bile acids are the toxic end products of hepatic cholesterol metabolism. They are synthesised from early in gestation and excreted via the placenta. The mechanism for transplacental excretion of bile acids is not known. The gene and protein expression of the nuclear receptors responsible for hepatic bile acid metabolism and transport was studied in eight normal and fourteen cholestatic placentas, and in an ex vivo model. The expression of the nuclear receptor FXR and several of it's target genes and of PXR and CAR was found to be very low in both normal and cholestatic placenta.