Table 7

Parameters generated from a kinetic model for the interaction of diclofenac and quinidine with CYP3A47-a

ReactionKS1 7-b KS2 7-b Factor7-b δVmax 7-b Factor7-b Equation7-b
mM μM pmol/min/mg
R-Warfarin 10-hydroxylation0.3  ± 0.118.2  ± 3.50.8  ± 0.2119 ± 13 (V max W)5.9 ± 0.8 (α)1
Quinidine 3-hydroxylation0.3  ± 0.125.3  ± 2.80.5  ± 0.2156 ± 6 (V max Q)0.7 ± 0.2 (β)2
  • 7-a  The kinetic model is shown in Fig. 2 and equations are described under Experimental Procedures.

  • 7-bV max Wand V max Q are the maximum velocities for the 10-hydroxylation of R-warfarin and 3-hydroxylation of quinidine, respectively; K S1 is the dissociation constant for EES 1 andK S2 for EES 2; δ, α, and β are the factors by which K S1 (orK S2), k 1, andk 2 are influenced upon binding of a second substrate to the enzyme. Data are presented as mean ± standard error.