Real time reverse transcriptase polymerase chain reaction was applied for the mRNA expression measurement of 8 bile acid transport correlative proteins, organic anion transporting polypeptide (OATP)1A2, OATP1B1, multidrug resistance protein (MRP)1, MRP2, anion exchanger (AE)2, bile salt export pump (BSEP), multidrug resistance 3, and familial intrahepatic cholestasis (FIC)1, in normal human placentas (n=20) and those with ICP (n=20).
Bile salt concentration in bile of BSEP-negative/MRP2-positive PFIC patients was 0.2 +/- 0.2 mmol/L (n = 9; <1% of normal) and in BSEP-positive PFIC patients 18.1 +/- 9.9 mmol/L (n = 3; 40% of normal).