Fig. 3

No role of ENaC and VDCC in the Ca²⁺ response. A-B Ca²⁺ microfluorimetry. Representative traces of mEEC stimulated with trypsin (20 µg/ml) challenged with (A) amiloride (10 µM), B nifedipine (10 µM). C Displays the percentage of responding cells to stimulation with either amiloride (Ami), nifedipine (Nif) and aprotinin (Apr, (10 µg/ml). Data is represented as mean ± SEM. ** p < 0.01, using one way ANOVA corrected from multiple testing with Dunnett’s multiple comparison test and compared to the trypsin condition. D Representative traces of mEEC stimulated with amiloride (10 µM) + trypsin (20 µg/ml). E–F Representative traces for trypsin stimulation of primary mEEC in Na⁺-free and Ca²⁺-free extracellular solution. Ionomycin (2 µM) was applied at the end of each protocol as positive control. N = at least 3 different experiments on a total minimum of 300 cells. G Whole-cell patch-clamp experiments of mEEC applying a voltage step protocol ranging from -120 mV holding to + 80 mV in + 20 mV steps in control (Ctrl) condition and in the presence of nifedipine (3 µM), an inhibitor of VDCC. H Current (I) Voltage (V) relationship for currents extracted from steady-state currents in. Insert represents the difference in current amplitude between control (Ctrl) and nifedipine (Nif) condition. Tryp = trypsin, Am = amiloride, Nif = nifedipine, Apr = aprotinin, Iono = ionomycin