Figure 15.

Inhibition of clathrin-mediated endocytosis significantly decreases the inhibitory effect of Cx30 on ENaC.A and B, representative whole-cell current traces recorded in oocytes expressing ENaC alone (left panels) or coexpressing ENaC with Cx30 (right panels) incubated for 1 h in standard incubation solution containing 0.02% DMSO (A; mock incubation) or 30 μM Pitstop-2 with 0.02% DMSO (B; Pitstop-2 was dissolved in DMSO to prepare a stock solution). Application of amiloride (Ami, 2 μM) is indicated by filled bars. Dashed lines indicate zero current level. C, ΔI_Ami values from similar experiments as shown in the representative traces in A and B. Mean ± SEM and data points for individual oocytes are shown; ∗∗∗p < 0.001; Kruskall–Wallis with Dunn’s post hoc test (n = 36 for each group, N = 3). D, relative inhibitory effect of Cx30 on ENaC calculated from the data shown in C essentially as described in Figure 3. DMSO, dimethyl sulfoxide. Mean ± SEM and data points for individual oocytes are shown; ∗∗∗p < 0.001; Mann–Whitney test.