FIG 7.

Evaluation of the concentration-dependent inhibition of OAT- and OCT-mediated PAS uptake by NSAIDs, PPIs, metformin, and cimetidine. The kinetics of NSAIDs and PPIs on inhibition of 20 μM PAS uptake by stably transfected HEK-OAT1 (●) and HEK-OAT3 (○) cells and of cimetidine and metformin on 5 μM PAS uptake by stably transfected HEK-OCT1 (●) and HEK-OCT2 (○) cells were estimated. The NSAIDs, PPIs, metformin, and cimetidine showed potent inhibition of PAS uptake by HEK-OAT1, HEK-OAT3, HEK-OCT1, and HEK-OCT2 cells according to the concentration gradient. The estimated IC₅₀ was calculated by nonlinear kinetics using WinNonlin software (version 5.1). Data are presented as the means ± SDs from three or more independent experiments and are the level of uptake as a percentage of that for the control (no inhibitor).