Tungstate has no effect on KCa3.1 (IK1) channel activity.

(A) Whole-cell recordings of KCa3.1 in murine 3T3 fibroblasts. KCa3.1 currents were pre-activated by infusion of 1 μM Ca2+ via the patch-pipette as previously described [38]. Pre-activated currents (control) were not changed by 1 mM tungstate (1 mM WO42-). (B) Average data showing pre-activated KCa3.1 current densities before and after tungstate application (P > 0.99, Mann-Whitney U-test; n = 4). (C) Average changes (in %) of pre-activated KCa 3.1 currents in response to 1 mM tungstate (1 mM WO42-) in the absence or presence of KCa3.1 activator SKA-31, as indicated. The SKA-31-potentiated KCa3.1 current was likewise insensitive to 1 mM tungstate (P = 0.56, Mann-Whitney U-test). Numbers in brackets indicate the number of cells tested in each experimental condition. (DOCX)