Table 1

Michaelis-Menten kinetic parameters for riluzole biotransformation by human hepatic microsomes and CYP1A-expressing yeast microsomes

Enzyme sourceCosubstrateVmaxKmClint
μM
Hepatic microsomesNADPH513  ± 361-a 29.7  ± 3.517.281-c
CYP1A2-yeast microsomesNADPH2.24  ± 0.121-b 25.7  ± 2.20.091-d
CYP1A1-yeast microsomesNADPH7.61  ± 0.341-b 6.24  ± 0.551.221-d
Hepatic microsomesUDPGA62.0  ± 10.51-a 118  ± 270.531-c
  • Clint = intrinsic metabolic clearance.

  • 1-a pmol/min/mg.

  • 1-b min−1.

  • 1-c μl/min/mg.

  • 1-d μl/min/pmol.

  • Values are mean ± S.E.M.