Figure 10.

In oocytes coexpressing ENaC and Cx30, the stimulatory effect of chymotrypsin on ENaC currents is similar to that in oocytes expressing ENaC alone. A and B, Left panels, representative whole-cell current traces recorded in an oocyte expressing ENaC alone (A) and in an oocyte coexpressing ENaC and Cx30 (B). Application of amiloride (Ami, 2 μM) or chymotrypsin (2 μg/ml) is indicated by filled and gray bars, respectively. Dashed lines indicate zero current level. Right panels, ΔI_Ami values obtained from similar experiments as shown in the representative traces (left panels) before (−) and after (+) chymotrypsin application. Lines connect data points obtained in an individual oocyte; ∗∗∗p < 0.001; Wilcoxon matched-pairs signed-rank test (n = 14, N = 2). C, summary of the individual data shown in (A and B) normalized as relative stimulatory effect of chymotrypsin on ΔI_Ami. Mean ± SEM and data points for individual oocytes are shown; n.s., not significant; Student’s ratio t-test.