Fig. 6.

Inhibition of human organic anion transporters 1 and 3 (hOAT1 and hOAT3)-mediated hydrochlorothiazide (HCTZ) uptake by probenecid and valsartan. Uptake of 10 μM HCTZ by hOAT1 and hOAT3 in the presence of increasing concentration of probenecid (A and B) and valsartan (C and D) was measured in both transporter-expressing and control human embryonic kidney-293 cells. Transporter-specific uptake was obtained by subtracting uptake in control cells from uptake in transporter-expressing cells. Uptake was measured after a 5-min incubation at 37°C. Data are presented as means ± SD.