Drug Added | Intracellular Drug | Intracellular Drug Concentration | Accumulation Factor1-a | Drug Initially Added to Medium in Cells |
---|---|---|---|---|
pmol/106 cells ± S.D. | nM | % | ||
Expt. I: Direct centrifugation | ||||
Dolastatin 10 | 0.0601-b | 92 | 1840 | 68 |
Vinblastine | 0.063 ± 0.003 | 97 | 97 | 3.4 |
Expt. II: Centrifugation through oil | ||||
Dolastatin 10 | 0.031 ± 0.001 | 46 | 920 | 41 |
Vinblastine | 0.044 ± 0.01 | 61 | 61 | 2.4 |
Cells were treated for 24 h with 50 pM [3H]dolastatin 10 or 1.0 nM [3H]vinblastine (the IC50 values). Each experiment was performed twice, with triplicate values obtained with both drugs, except that the silicone oil experiment with vinblastine was performed three times.