TABLE 2

Inhibition of OATP1B3- and ABCC2-mediated CCK-8 transport by CsA and MK571

Intact OATP1B3-expressing MDCKII cells or inside-out membrane vesicles from ABCC2-expressing MDCKII cells were incubated with labeled CCK-8 in the absence or presence of CsA or MK571. Data represent means ± S.D. from three experiments each determined in triplicate (intact cells) or duplicate (membrane vesicles).



CsA

MK571

OATP1B3
ABCC2
OATP1B3
ABCC2
Ki (μM) 1.2 ± 0.1 24.0 ± 3.7 0.60 ± 0.03 8.5 ± 1.5
IC50 (μM)a
1.8 ± 0.1
45.3 ± 7.0
0.85 ± 0.05
16.1 ± 2.8
  • a Transport rates in the absence of inhibitor: 76 ± 5 pmol · mg-1 · min-1 for OATP1B3 and 99 ± 10 pmol · mg-1 · min-1 for ABCC2. Transport of 5 μM CCK-8 was measured for 1 min in the case of OATP1B3 and transport of 7 μM CCK-8 for 3 min in the case of ABCC2.