TABLE 1

Imidazole agonists with experimental PXR data and predictions

Side-by-side comparison of Emax and EC50 values were obtained utilizing the two dose response curve modeling equations and the experimental Emax values. Emax refers to the maximum increase in -fold induction obtained when DPX-2 cells were treated with PXR agonists over cells treated with the negative control, 0.1% DMSO. The experimental Emax is the highest observed -fold induction for each compound. The -fold induction results were corrected for cell viability and represent the mean of three or four determinations. For further experimental details, see Materials and Methods.


Compound

Prediction from Bachmann et al. (2004)

Via Simple Emax Model

Via Hill's Model

Experimental Emax
Emax
EC50
Emax
EC50
Concentration
Emax
μM μM μM μM
Rifampicin 33.9 4.1 35 4.7 20 31
Mifepristone 16.2 3.1 16.5 4 10 15.3
Androstenol 9.9 1.9 9 1.8 10 8.8
CDD3501 22.4 2.3 19 1.8 10 20.3
CDD3508 36 4.1 34 3.9 10 29.7
CDD3530 26.6 3.6 22.5 3.1 10 24
CDD3532 20.6 1.5 20.9 2 20 20.2
Clotrimazole 16 0.8 15 0.8 20 16.2
CDD3536 24 2.4 24.2 2.5 20 22.2
CDD3538 9.6 30.2 1.3 27.8 1.1 10 30.9
CDD3540 25 31.5 2.3 26.9 1.7 10 32.7
CDD3543
3.4
25.7
1.4
25.1
1.4
10
25.7