M1

M2

M3

M4

 

Vm

Km

Vm

Km

Vm

Km

Vm

Km

MOUSE

0.34 ± 0.05

86.25 ± 34.0

0.28 ± 0.03

48.12 ± 18.1

0.52 ± 0.07

64.1 ± 27.7

0.59 ± 0.07

239.2 ± 55.1

Rat

0.04 ± 0.01

59.02 ± 16.5

0.03 ± 0.01

17.3 ± 8.6

0.33 ± 0.02

74.2 ± 8.1

0.19 ± 0.02

53.12 ± 14.2

Rabbit

0.14 ± 0.01

50.22 ± 10.2

0.16 ± 0.01

21.4 ± 3.3

0.50 ± 0.02

71.0 ± 5.3

0.59 ± 0.07

122.8 ± 39.1

Dog

0.31 ± 0.06

115.85 ± 38.8

0.39 ± 0.06

76.2 ± 32.0

1.20 ± 0.14

75.1 ± 32.0

0.12 ± 0.03

128.5 ± 68.5

Pig

1.02 ± 0.32

73.0 ± 21.1

0.56 ± 0.12

53.6 ± 19.7

0.57 ± 0.1

90.21 ± 22.6

0.65 ± 0.08

120.1 ± 35.5

Baboon

0.16 ± 0.03

59.2 ± 8.8

0.26 ± 0.04

37.78 ± 6.5

0.68 ± 0.1

80.5 ± 15.2

0.15 ± 0.01

162 ± 22.1

Human

0.36 ± 0.1

96.1 ± 10.1

0.26 ± 0.02

41.2 ± 7.1

1.51 ± 0.4

78.4 ± 14.1

0.62 ± 0.05

674 ± 73.15

Hepatocytes

0.39 ± 0.13

35.58 ± 40.1

0.97 ± 0.26

56.1 ± 38.7

1.7 ± 0.52

67.6 ± 49.4

ND

ND

Vm: μM/min/mg protein
Km: μM
ND – Not Detectable
Table 1: Kinetic parameters for 17-OHPC hydroxylated metabolites (M1-M4) observed in Rabbit, Rat, Dog, Mouse, Pig, Baboon, Human Liver Microsomes and Human Hepatocytes. All the experiments were performed in triplicate and the values are reported as mean ± SD. The kinetic parameters were calculated by expressing metabolite levels in terms of 17-OHPC equivalents.