TABLE 2

Comparison of inhibitory potentials of known PEPT1 substrates on LY2140023 and Gly-Sar uptake

Compounds	IC₅₀ against Gly-Sar^A	IC₅₀ against LY2140023	IC₅₀ against LY2140023	Mean IC₅₀ against LY2140023
	mM	mM	mM	mM
ALA	0.78 ± 0.26	1.77 ± 0.21	1.56 ± 0.22	1.67
Captopril	5.64 ± 0.81	13.45 ± 2.16	22.58 ± 3.26	18.02
Cefadroxil	1.88 ± 0.35	4.05 ± 0.44	5.93 ± 1.47	4.99
Cephalexin	11.1 ± 1.98	14.27 ± 3.23	12.95 ± 1.04	13.61
Enalapril	2.13 ± 0.36	10.97 ± 2.64	10.35 ± 0.42	10.66
Gly-Sar	N.A.	1.29 ± 0.26	0.69 ± 0.17	0.99
L- DOPA	14.9 ± 2.45	25.27 ± 2.57	26.52 ± 9.38	25.90
Valacyclovir	0.74^B	0.41 ± 0.05	0.50 ± 0.11	0.46
LY2140023	0.018^C

↵^A Values of IC₅₀ against Gly-Sar (50 μM) were obtained from Zhang et al. (2004) except for valacyclovir.
↵^B The K_i value for valacyclovir was obtained from Ganapathy et al. (1998).
↵^C The mean IC₅₀ values from two separate experiments, 0.023 ±0.09 and 0.013 ± 0.07 mM.