TABLE 1

K_m and K_i for rOat1, rOat3, and RFC-1 The K_m and K_i values for the uptake by rOat1- and rOat3-LLC-PK1 cells, and by RFC-1-MDCKII cells was determined by nonlinear regression analysis. Compounds in parentheses represent substrates for determination of K_i values.

Substrate/Inhibitor	rOat1	rOat3	RFC-1
	μM	μM	μM
PAH	K_m = 47.0^a, 59.9^b	K_i = 398^a (PCG), 1350^b (pravastatin)	K_i > 1000 (MTX)
PCG	K_i = 418^b, 800^a (PAH)	K_m = 82.6^a K_i = 52.8^b (pravastatin)	K_i > 1000 (MTX)
5-MTHF	K_i > 1000 (MTX)	K_i > 1000 (MTX)	K_i = 5.03 ± 3.05^c (MTX)

↵ a Nagata et al., 2002
↵ b Hasegawa et al., 2002
↵ c Mean ± S.D