. Author manuscript; available in PMC: 2010 Mar 2.

Published in final edited form as: Int J Pharm. 2008 Jun 27;362(1-2):93–101. doi: 10.1016/j.ijpharm.2008.06.018

Table 1.

Uptake of [³H] L-Ala (7.6 nM), [³H] L-Arg (11.9 nM), [³H] L-Phenylalanine (10 nM) and [³H] Glysar (125 nM) by Caco-2 in the presence of corresponding nonradioactive substrate and prodrugs.

Units = fraction uptake of control per mg of protein	[³H] Alanine	[³H] Arginine	[³H] Phenylalanine	[³H] Gly-Sar
control	6.58 ± 0.75	7.81 ± 1.23	16.27 ± 2.66	2.38 ± 0.25
corresponding nonradioactive substrate^‡	2.63 ± 0.67^*	3.60 ± 0.37^*	2.21 ± 0.16^*	0.45 ± 0.04^*
AACV^†	1.90 ± 0.29^*	6.50 ± 1.17	9.22 ± 2.11	2.49 ± 0.32
SACV^†	7.64 ± 0.79	8.44 ± 0.67	12.72 ± 1.12	0.35 ± 0.05^*
IACV^†	4.93 ± 0.75	5.05 ± 0.67^*	4.06 ± 0.33^*	0.70 ± 0.06^*
EACV^†	6.59 ± 1.65	8.54 ± 0.24	14.58 ± 2.60	2.18 ± 0.09
VACV^†	6.25 ± 1.40	8.50 ± 1.17	12.92 ± 0.17	0.87 ± 0.1^*

Values are mean ± S.D. (n=4 to 8).

indicates p<0.05.

^‡

Uptake of radioactive substrate in the presence of corresponding nonradioactive competitive substrate (5 mM)

^†

Uptake of radioactive substrate in the presence of prodrugs (5 mM)