TABLE 1

Effect of various compounds on the uptakes of DAPI and [³H]cimetidine mediated by hMATEs stably expressed in MDCKII cells

The uptakes of DAPI (0.5 μM) and [³H]cimetidine (50 nM) were evaluated at 37°C and pH 7.4 for 10 min (DAPI) or 20 s ([³H]cimetidine) in MDCKII cells stably expressing hMATE1, those expressing hMATE2-K, and mock cells in the presence or absence of a test compound. The specific uptakes by hMATEs are presented as means ± S.E. (n = 8). The control values for DAPI uptake were 2.34 and 3.70 FI/mg protein, respectively, for hMATE1 and hMATE2-K, and for cimetidine uptake were 0.75 and 0.39 pmol/mg protein, respectively.

Compound	Conc.	Uptake
		hMATE1		hMATE2-K
		DAPI	[³H]Cimetidine	DAPI	[³H]Cimetidine
	mM	%control
None (control)		100.0 ± 1.4	100.0 ± 3.0	100.0 ± 1.5	100.0 ± 1.5
Cimetidine	0.2	N.D.	N.D.	24.6 ± 1.6*	3.1 ± 0.7*
Clonidine	0.2	45.4 ± 1.3*	18.4 ± 0.5*	65.2 ± 3.3*	24.2 ± 1.2*
Corticosterone	0.2	34.0 ± 2.0*	27.6 ± 0.4*	49.8 ± 2.6*	13.5 ± 0.5*
Diphenhydramine	0.2	34.1 ± 1.5*	23.6 ± 0.9*	57.2 ± 2.1*	41.4 ± 1.7*
Diltiazem	0.2	N.D.	5.8 ± 0.2*	47.4 ± 2.1*	33.6 ± 2.2*
Estrone-3-sulfate	0.2	80.5 ± 2.4*	65.9 ± 0.6*	100.8 ± 4.6	70.0 ± 2.8*
Guanidine	2	92.3 ± 2.6	92.9 ± 2.8	103.8 ± 1.8	87.8 ± 0.8*
Imipramine	0.2	1.0 ± 0.6*	11.5 ± 0.3*	19.2 ± 1.4*	25.9 ± 0.6*
MPP	0.2	60.6 ± 1.7*	27.7 ± 0.4*	82.8 ± 3.6*	27.3 ± 1.8*
Nicotinamide	0.2	105.1 ± 2.8	106.6 ± 5.1	112.0 ± 2.8*	97.0 ± 1.7
NMN	2	111.1 ± 1.8*	123.4 ± 5.0*	117.7 ± 4.4*	78.9 ± 1.5*
Norepinephrine	0.2	74.9 ± 1.8*	89.0 ± 1.2*	67.7 ± 2.9*	65.3 ± 3.8*
PAH	0.2	96.6 ± 6.0	132.0 ± 3.6*	105.3 ± 2.0	102.6 ± 4.1
Procainamide	0.2	96.4 ± 3.0	58.2 ± 1.0*	93.3 ± 3.3	30.5 ± 1.3*
Serotonin	0.2	93.3 ± 2.9	44.9 ± 2.0*	107.2 ± 4.4	69.2 ± 4.0*
TEA	2	54.6 ± 2.7*	23.6 ± 0.2*	88.4 ± 1.9*	27.0 ± 0.2*
TPP	0.2	12.9 ± 1.6*	13.0 ± 0.5*	67.9 ± 3.3*	26.4 ± 0.3*
Verapamil	0.2	N.D.	10.8 ± 0.6*	10.9 ± 1.4*	11.8 ± 0.7*

MPP, 1-methyl-4-phenylpyridinium; NMN, N-methylnicotinamide; PAH, p-aminohippurate; TPP, thiamine pyrophosphate; N.D., not detected.
↵* Significantly different from the value for control at p < 0.05.