Relationship between hepatic membrane protein MRP3 and nuclear receptor RXR? / 第三军医大学学报

ABSTRACT

Objective To investigate the relationship between the hepatic membrane protein MRP3(multidrug resistance-associated protein 3,MRP3) expression and the nuclear hormone receptor RXR?(retinoid-X receptor alpha,RXR?)expression in both cultured hepatoma cell HepG2 and bile duct ligated(BDL) rat liver.Methods Total cellular protein and nuclear protein were isolated from HepG2 cells induced by chenodeoxycholic acid(CDCA) or phenobarbital(PB),as well as from the liver tissue of BDL rats.The protein expressions of MRP3 and RXR? were determined by Western blotting.Results The membrane protein MRP3 expression was significantly enhanced and the nuclear receptor RXR? expression was suppressed by CDCA or PB in HepG2 cells.Similarly up-regulation of MRP3 and down-regulation of RXR? were also observed in BDL rat liver.Conclusion The up-regulation of hepatic membrane protein MRP3 may be associated with down-regulation of nuclear receptor RXR?.