Table 11

Parameters used in the simulation of mechanism-based inhibition

SubstrateInhibitor
 Dose  =  2 μmol Dose  =  5000 μmol
 Fa =  0.8 Fa =  0.8
 fb =  0.1 fb =  0.2
 ka =  0.01 min−1  ka =  0.02 min−1
 Km =  100 μM Km =  10 μM
 Vmax(0)  =  200 μmol/min Vmax(0)  =  30 μmol/min
 Vd =  70 L Vd =  20 L
 Kp =  1 Kp =  1
EnzymePhysiological parameters
 kdeg =  0.0005 min−1  Q  =  1610 mL/min
 Ki,app =  20 μM Vh =  2800 mL
 kinact =  0.06 min−1  Vportal =  70 mL
 E0 =  5 nmol P450/g liver
  • Q, blood flow rate; Csys and Isys, concentration in systemic blood; Vd, volume of distribution in the central compartment; Cportal and Iportal, concentration in portal vein; Vportal, volume of portal vein; Ch and Ih, concentration in liver; Vh, volume of liver; fb, unbound fraction in blood; CLint, intrinsic metabolic clearance; Fa, fraction absorbed from the intestinal tract; Km, Michaelis constant for the metabolic elimination; Vmax, Maximum metabolic rate for the metabolic elimination; Kp, liver-to-blood concentration ratio.