Figure 2.

Transport measurements in transiently transfected HEK293 cells. HEK293 cells were transiently transfected with the indicated carriers SLC10A4, DAT, CHT1, or SERT, respectively. The uptake of 5 µM [³H]dopamine, 5 µM [³H]norepinephrine, 5 µM [³H]choline, or 5 µM [³H]serotonin was measured over the given time periods in the presence and absence of Na⁺ (for CHT1 Na⁺ was replaced by Li⁺). Transport via DAT, CHT1, and SERT was blocked by the specific inhibitors nomifensine (10 µM), hemicholinium-3 (HC-3, 1 µM), and citalopram (2 µM), respectively. Values represent mean ± SD of representative experiments, each with quadruplicate determinations (n = 4). *Significantly different from control with p < 0.001. ^#Significantly different from positive uptake, p < 0.001.