Different effect of cyclosporine and tacrolimus on renal expression of P-glycoprotein in human kidney transplantation.

Abstract Objective To investigate the differential effects of cyclosporine (CsA) and tacrolimus (TAC) on renal expression of P-glycoprotein (P-gp) in a cohort of kidney transplant recipients. Methods We enrolled 78 cadaveric kidney transplant recipients recuring basal immunosuppressive protocol with prednisone + mycophenolate mofetil + calcineurin inhibitor (CsA or TAC). Results We performed a 3-year analysis of 60 patients. There was no difference in age, gender, or cold ischemic time between two groups, Serum creatinine, urine protein, and blood fat levels of the CsA group were significantly higher than the TAC group ( P P P ® P-gp was predominantly present in the a tubular apical membrane, basal membrane, and cytoplasm. The intensity and extent of tubular staining score in the CsA group were lower compared with the TAC group ( P P Conclusion Less P-gp expression in the CsA group than the TAC group may be the molecular action pathway of the high incidence of CsA nephrotoxicity and CsA-induced CAN. This study perhaps unraveled a novel interpretation that the differences of CsA and TAC on long-term allograft survival were due to increases dynamic effects of CsA at the exposures employed in this study.