Fig. 2.

Time course uptake experiments of ∼200 nM [³H]atenolol, ∼10 µM [¹⁴C]metformin, and ∼15nM [³H]MPP by CHO-OCT2 (A, B, and C), CHO-MATE1 (D, E, and F), or CHO-MATE2-K (G, H, and I). Uptake is expressed as clearance (µl cm⁻²). Each point is the mean of triplicate measures of uptake determined in a single representative experiment. Experiments with MATE1- and MATE2-K-expressing CHO cells were measured in the presence (triangles) or absence (circles) of 1 mM unlabeled MPP. Experiments with OCT2-expressing cells also included parallel measurements with wild-type CHO cells (triangles).