Sucrose concentration | [3H]AFB1-GSH uptake rate |
---|---|
mm | pmol/mg/min (% of control) |
250 | 85 ± 6 (100) |
333 | 67 ± 4 (79 ± 5) |
500 | 60 ± 1 (71 ± 1) |
750 | 39 ± 1 (46 ± 2) |
1000 | 19 ± 1 (23 ± 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 at 37° for 120 sec in transport buffer containing different concentrations of sucrose. 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 presence of 250 mm sucrose. Results are mean ± standard error of triplicate determinations in a single experiment.