Table I.

Enzyme Kinetic Parameters for the Formation of EETs and HETEs in Rat Heart, Lung, Kidney, and Liver Microsomes

Parameters		Heart	Lung	Kidney	Liver
5,6-EET	V max	49.3 ± 3.4	244 ± 11	–	596 ± 71
	h	1.40 ± 0.13	2.41 ± 0.45	–	–
	K m	268 ± 35	89.2 ± 7.1	–	124 ± 26
	Clint	0.18	2.74	–	4.83
	R 2	0.99	0.95	–	0.95
8,9-EET	V max	38.2 ± 2.7	55.1 ± 3.1	202 ± 8	592 ± 35
	h	–	–	2.25 ± 0.33	1.71 ± 0.33
	K m	310 ± 50	141 ± 18	28.3 ± 1.4	26.9 ± 2.8
	Clint	0.12	0.39	7.15	22
	R 2	0.96	0.98	0.99	0.95
11,12-EET	V max	76.6 ± 4	136 ± 7	775 ± 40	1,024 ± 57
	h	–	–	2.30 ± 0.23	2.13 ± 0.50
	K m	270 ± 33	172 ± 24	71.3 ± 4.5	24.2 ± 2.4
	Clint	0.28	0.79	10.9	42.4
	R 2	0.97	0.96	0.99	0.92
14,15-EET	V max	146 ± 8	204 ± 8	283 ± 44	729 ± 60
	h	–	–	–	–
	K m	570 ± 60	401 ± 32	109 ± 29	68.4 ± 12.6
	Clint	0.26	0.51	2.59	10.7
	R 2	0.99	0.99	0.96	0.94
19-HETE	V max	–	1.18 ± 0.03	100 ± 19	177 ± 18
	h	–	–	–	–
	K m	–	33.8 ± 3.5	166 ± 52	94.6 ± 19
	Clint	–	0.03	0.60	1.87
	R 2	–	0.97	0.91	0.94
20-HETE	V max	0.73 ± 0.03	9.19 ± 1.28	812 ± 62	1,118 ± 264
	h	1.77 ± 0.27	–	1.91 ± 0.26	1.23 ± 0.22
	K m	59.6 ± 6.1	87.8 ± 27.1	58.7 ± 6.7	108 ± 45
	Clint	0.01	0.10	13.9	10.4
	R 2	0.95	0.93	0.97	0.96

Data are the mean ± SEE. V _max (in picomoles per minute per milligram of protein), K _m (in micromolars), and h were determined as per simple Michaelis–Menten or sigmoidal model (Eq. 1). Cl_int (in microliters per minute per milligram of protein) was calculated as V _max/K _m