Figure 4.

Effect of compound 14 on NCX3 activity in BHK-NCX3 cells. (A,B) Representative superimposed traces and quantification of the effect of compound 14 on Na⁺-free-induced [Ca²⁺]_i increase through NCX3 reverse mode of operation in Fura-2-loaded BHK-NCX3 cells. The bar graph reports the mean ± SEM of the maximal [Ca²⁺]_i responses measured in approximately 50 cells per group. Averaged data from four different experimental sessions were normalized as the percentage of controls. *p < 0.05 vs control and 1 μM; **p < 0.05 vs all. (C,D) Representative I_NCX traces recorded by whole-cell patch-clamp electrophysiology in control cells and in cells treated with compound 14 (10 μM). The bar graphs in (D) report the mean ± SEM of the forward and reverse NCX3 current densities, respectively, measured in nine cells for each experimental group. Reverse I_NCX amplitude was measured at +60 mV, while forward I_NCX was measured at −120 mV. *p < 0.05 vs each internal control.