Compound | Concentration | [3H]AFB1-GSH uptake |
---|---|---|
μm | % of control | |
None (control) | 100 | |
GSH and derivatives | ||
GSH | 5000 | 113 ± 9 |
GSSG | 100 | 65 ± 1 |
500 | 20 ± 3 | |
LTC4 | 1 | 50 ± 1 |
10 | 6 ± 0.1 | |
S-Methyl GSH | 10 | 102 ± 4 |
S-Ethyl GSH | 10 | 105 ± 2 |
S-Butyl GSH | 10 | 77 ± 2 |
S-Hexyl GSH | 10 | 28 ± 4 |
S-Octyl GSH | 10 | 13 ± 1 |
S-Decyl GSH | 10 | 4 ± 1 |
Steroid glucuronides | ||
17β-Estradiol 17-(β-d-glucuronide) | 100 | 14 ± 1 |
17β-Estradiol 3-(β-d-glucuronide) | 100 | 103 ± 3 |
16α-17β-Estradiol 17-(β-d-glucu ronide) | 100 | 13 ± 1 |
16α-17β-Estradiol 16-(β-d-glucu ronide) | 100 | 83 ± 1 |
16α-17β-Estradiol 3-(β-d-glucu ronide) | 100 | 105 ± 6 |
17β-Estradiol 3-sulfato-17-(β-d- glucuronide) | 100 | 3 ± 0.1 |
Membrane vesicles (8 μg of protein in a 25-μl reaction volume) from MRP-transfected T14 cells were incubated with 250 nm[3H]AFB1-GSH in transport buffer for 120 sec at 37° in the presence of the indicated concentration of inhibitor. Transport was measured as described in Experimental Procedures, and ATP-dependent [3H]AFB1-GSH uptake was determined and calculated as percentage of control uptake in the absence of inhibitors. Results are mean ± standard error of triplicate determinations in a single experiment. The control rate of [3H]AFB1-GSH uptake in this experiment was 131 ± 6 pmol/mg/min.