Figure 4.

With 8 days of the Na⁺, K⁺, and Cl⁻-restricted diet, epithelial Na⁺ channel (ENaC) subunit abundance is similar in pendrin-null [knockout (KO)] and wild-type (WT) kidneys, although subunit abundance is greater in kidneys from female mice than from male mice. Shown are representative α-, β-, and γ-ENaC subunit immunoblots of kidney lysates from male and female WT and pendrin-null mice following 4 days of the NaCl-replete, K⁺-deficient diet (treatment 2), and then 8 days of the Na⁺, K⁺, and Cl⁻-deficient diet (treatment 1; A, D, and F) and their respective band densities (B, C, E, G, and H). As shown, the abundance of both the β-ENaC subunit and the 85-kDa fragment of γ-ENaC were higher in female than in male pendrin-null mice, although the abundance of the other ENaC subunits was similar. However, in both sexes, ENaC subunit abundance was similar in KO and WT mice. Open circles represent individual data points of mice from each group. Groups were compared with one-way ANOVA with a Holm–Sidak posttest (30-kDa α-ENaC and β-ENaC) and a Tukey posttest (85-kDa γ-ENaC). *P < 0.05.