TABLE 1

Mean IC50 values (±S.D.; n = 3) for the inhibition of M1 formation in human (HLC), dog (DLC) liver cytosol and human plasma by aldehyde oxidase (AO), carboxylesterase (CES), and xanthine oxidase (XO) inhibitors

InhibitorTargeted EnzymeHLCDLCHuman Plasma
IC50 ± S.D. (μM)
β-EstradiolAO1.88 ± 1.02>50>10
DCPIPAO2.14 ± 0.81>50>10
MenadioneAO0.71 ± 0.27>50>10
RaloxifeneAO0.33 ± 0.11>50>10
LoperamideAO/CES0.15 ± 0.02>504.73 ± 1.27
BNPPCES0.50 ± 0.1315.6 ± 2.26.52 ± 1.48
AllopurinolXO>50>50>10
  • DCPIP, 2,6-dichlorophenolindophenol; BNPP, bis-(p-nitrophenyl) phosphate.