Table 2

Xenobiotics uptake by hOCTN2-transfected HEK293 cells

Xenobiotic	Cell-to-Medium Ratio
Xenobiotic	hOCTN2-transfected cells	Mock cells	Net uptake
	μl/mg protein/5 min
l-[³H]Carnitine, 10 nM	1388.5 ± 24.83^*	36.2 ± 0.36	1352.3
d-[³H]Carnitine, 7.7 nM	734.2 ± 3.02^*	18.6 ± 1.04	715.6
[³H]Acetyl-l-carnitine, 7.7 nM	608.0 ± 7.60^*	19.7 ± 1.71	588.3
[¹⁴C]TEA, 208 μM	11.3 ± 0.36^*	9.2 ± 0.18	2.2
[³H]MPP, 14.7 nM	33.6 ± 0.57	32.7 ± 0.36	0.9
[¹⁴C]Guanidine, 34.0 μM	30.2 ± 0.15	30.3 ± 0.08	−0.1
[³H]Pyrilamine, 17.9 nM	495.3 ± 15.64^*	375.2 ± 14.15	120.1
[³H]Cimetidine, 44.2 nM	24.8 ± 0.97	24.3 ± 0.55	0.5
[³H]Quinidine, 33.3 nM	461.1 ± 7.55^*	361.7 ± 16.12	99.4
[³H]Verapamil, 6.4 nM	489.4 ± 5.91^*	400.9 ± 17.79	88.5
[³H]Actinomycin D, 113.6 nM	574.6 ± 13.12	637.0 ± 62.61	−62.4
[³H]PAH, 204 nM	8.0 ± 0.39	7.8 ± 0.32	0.2
[³H]Valproate, 11.1 nM	21.6 ± 0.70^*	19.1 ± 0.41	2.5

Uptakes of xenobiotics in hOCTN2- and mock-transfected HEK293 cells were measured for 5 min at 37°C in transport buffer (pH 7.4). Each value represents mean ± S.E. of three determinations.

∗, p < .05: significantly different from the uptake by mock-transfected cells by Student’s t test.