Table 2

Apparent kinetic constants for total TRI metabolite formation

Species	V_max	K_m	V_max/K_m	r	N
	nmol/mg protein/min	mM
Male
Mouse	8.60 ± 4.50^2-b	0.378 ± 0.414	42.0 ± 28.5^2-b	0.95–0.99	5
Rat (high affinity)	0.96 ± 0.65^a,b	0.072 ± 0.082^2-c	23.8 ± 20.6^b,d	0.95–0.99	5
(low affinity)	2.48 ± 0.97^a,b	0.482 ± 0.104	5.3 ± 2.2^2-b	0.94–0.98	5
Human (high affinity)	0.52 ± 0.17^a,b	0.012 ± 0.003^2-c	48.0 ± 23.1^2-b	0.98–0.99	3
(low affinity)	0.93 ± 0.17^a,b	0.093 ± 0.026	10.7 ± 3.9^b,d	0.96–0.98	3
H1 (high affinity)	0.37	0.014	26.4	0.99	1
(low affinity)	0.88	0.123	7.2	0.98	1
H2 (high affinity)	0.61	0.009	67.8	0.98	1
(low affinity)	1.05	0.072	14.6	0.96	1
H3 (high affinity)	0.79	0.010	79.0	0.98	1
(low affinity)	1.24	0.075	16.5	0.97	1
Female
Mouse	26.06 ± 7.29	0.161 ± 0.029	162.8 ± 36.7	0.99	3
Rat (high affinity)	2.91 ± 0.71^2-b	0.042 ± 0.021	80.0 ± 33.9^2-b	0.96–0.98	3
(low affinity)	4.31 ± 0.31^2-b	0.111 ± 0.027	40.1 ± 7.1^b,d	0.92–0.99	3
Human (high affinity)	0.33 ± 0.15^a,b	0.026 ± 0.017^2-c	15.3 ± 10.1^b,d	0.97–0.99	3
(low affinity)	0.72 ± 0.60^a,b	0.160 ± 0.162	6.8 ± 5.6^b,d	0.96–0.99	3
H4 (high affinity)	0.19	0.014	13.6	0.99	1
(low affinity)	0.36	0.097	3.7	0.97	1
H5 (high affinity)	0.48	0.045	10.7	0.97	1
(low affinity)	1.42	0.333	4.3	0.99	1
H6 (high affinity)	0.38	0.013	29.2	0.99	1
(low affinity)	0.42	0.030	14.0	0.96	1

2-a Significantly different from the corresponding male mouse value.
↵2-b Significantly different from the corresponding female mouse value.
↵2-c Significantly different from the corresponding male rat (low affinity) value.
2-d Significantly different from the corresponding female rat (high affinity) value.