Table 4.

Differences in the half-maximal inhibitory concentration (IC₅₀ in μM; mean ± SD) between human and mouse OCT1

		Inhibitors
		Trimethoprim		Verapamil		Quinidine
		Human	Mouse	Human	Mouse	Human	Mouse
Substrates	Fenoterol	45.0 ± 3.45	23.3∗∗∗ ± 4.36	4.27 ± 0.63	12.6∗ ± 0.95	16.3 ± 1.83	10.4∗∗∗ ± 1.62
	Salbutamol	37.6 ± 7.77	11.3∗∗∗ ± 2.71	1.48 ± 0.18	6.91 ± 0.96	6.22 ± 1.48	8.95∗∗ ± 1.50
	Sumatriptan	12.0 ± 2.88	19.5∗ ± 3.49	8.40 ± 0.82	5.63∗∗∗ ± 1.38	25.2 ± 2.62	6.42 ± 1.19
	Zolmitriptan	34.9 ± 4.97	12.9∗∗∗ ± 1.64	1.30 ± 0.13	6.17∗∗∗ ± 1.82	8.61 ± 0.71	4.68 ± 0.40
	Ipratropium	10.9 ± 1.76	8.79 ± 1.22	8.66 ± 1.95	20.7∗ ± 3.46	28.9 ± 3.95	9.77∗∗ ± 0.57
	Trospium	18.5 ± 2.48	23.0 ± 3.76	5.99 ± 0.48	13.8 ± 1.56	18.1 ± 4.88	12.1∗∗∗ ± 2.08
	Methylnaltrexone	19.0 ± 4.36	6.70∗∗∗ ± 2.62	2.69 ± 0.52	10.3 ± 0.52	8.67 ± 1.48	4.37∗∗∗ ± 1.65
	Metformin	41.7 ± 6.65	12.9∗∗∗ ± 1.55	2.61 ± 0.48	6.06 ± 0.98	11.2 ± 2.48	7.02∗ ± 3.06

OCT, organic cation transporter.

∗P < .05, ∗∗ P < .01, ∗∗∗ P < .001 compared with human OCT1, Student’s t test with Bonferroni correction for 24 multiple tests.