Binding characteristics of [3H]verapamil and [3H]vinblastine to preparations of P-gp,Kd values for the two-affinity model, Hill coefficients of the respective affinity (n), maximum binding capacity of specific binding (Bmax), and slope of nonspecific binding (mean ± S.D., n = 4 for [3H]verapamil and individual results, n = 2 for [3H]vinblastine)
| Radioligand | Kd1 | Kd2 | n1 | n2 | Bmax | Nonspecific Binding |
|---|---|---|---|---|---|---|
| μm | μm | fmol/1 × 106 cells | fmol/1 × 106 cells/μm | |||
| [3H]verapamil | 0.56 ± 0.13 | 2.7 ± 0.5 | 1.2 ± 0.2 | 5.9 ± 0.7 | 1660 ± 671 | 90 ± 12 |
| [3H]vinblastine | 1.8/2.1 | 5.3/5.4 | 1.4/1.2 | 4.8/7.9 | 2070/2170 | 130/142 |