TABLE 1

Kinetic parameters derived from N-glucuronidation and N-glucosidation of mianserin and cyclizine by HLMs and expressed UGT2B10 enzymes supplemented with an equal amount of two UDP donors (UDP-glc and UDPGA)

Data are represented by mean ± S.D.

SubstrateEnzymeReaction TypeVmaxKmCLint
(pmol/min per milligram)(μM)(μl/min per milligram)
MianserinHLMGlucosidation32.8 ± 2.7613.6 ± 3.492.41 ± 0.65
HLMGlucuronidation311 ± 16.872.0 ± 7.164.32 ± 0.49
UGT2B10Glucosidation19.4 ± 1.0124.3 ± 3.280.80 ± 0.12
UGT2B10Glucuronidation25.1 ± 0.8928.9 ± 2.540.87 ± 0.08
CyclizineHLMGlucosidation1410 ± 11852.6 ± 8.9926.8 ± 5.10
HLMGlucuronidation1883 ± 12950.1 ± 7.1237.6 ± 5.90
UGT2B10Glucosidation310 ± 18.716.4 ± 2.8818.9 ± 3.51
UGT2B10Glucuronidation312 ± 16.921.14 ± 3.0914.8 ± 2.27

  • CLint, the intrinsic clearance; Km, the Michaelis constant; Vmax, the maximal velocity.