Concentration μM | α-Naphtoflavone | Docetaxel | 7-Epidocetaxel |
---|---|---|---|
1 | −100 (11.4) | N.T. | N.T. |
3 | N.T. | −2 (0.1) | −6 (0.4) |
10 | N.T. | +30 (0.6) | > +700 (N.A.) |
30 | N.T. | −22 (1.3) | +480 (N.A.) |
100 | N.T. | +378 (13.7) | +470 (37.1) |
Effects are given in % of controls without inhibitors (vehicle only) as means (S.D.) of triplicate. 7-ethoxyresorufinO-deethylase activity (EROD) was measured in 0.1 M phosphate buffer pH 7.4, containing 5 pmol rhCYP1B1/mL, 1 mM NADPH, and the molecule to bested. After 1-min preincubation at 37°C, reactions were started by the addition of ethoxyresorufin, 1 μM. Substrate and inhibitors were added in DMSO (1%, total final concentration). Reactions were stopped after 2-min incubation at 37° by the addition of 1 ml cold phosphate buffer 0.1 M, pH 7.4, containing 1% DMSO, vortex and kept on ice. After centrifugation at 4°C, the concentration of resorufin in the supernatants was measured with a spectrofluorimeter, using a calibration with reference resorufin.
N.A., not applicable; N.T., not tested.