Fig. 4

Effect of selected inhibitors on 5-HT clearance by placental explants (A, B) and primary trophoblast cells (C, D). The uptake of 5-HT and release of 5-HIAA was measured at initial 5-HT concentrations of 100 nM (A, C) and 100 µM (B, D) in the presence of 100 µM paroxetine (SERT and OCT3 inhibitor), 100 µM phenelzine (MAO-A inhibitor), 50 µM MK-571 (MRP2 inhibitor), or 500 µM probenecid (OAT inhibitor). The extent of 5-HT metabolism over a period of 4 h is expressed as the ratio of the concentrations of 5-HIAA and 5-HT. The results are shown relative to the control condition (CTRL) with no added inhibitor. Data are presented as medians with interquartile ranges; n = 5. Statistical significance was evaluated using the Mann-Whitney test. * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001