Fig. 6.

Compared with normal diet, long-term (14 days) dietary K⁺ restriction did not increase phosphorylated Na⁺-Cl⁻ cotransporter (pNCC) abundance. A: plasma [K⁺] was significantly lower on Mg²⁺-K⁺-deficient diet (D) and on K⁺-deficient diet compared with normal diet (N) and Mg²⁺-deficient diet (one-way ANOVA with Tukey’s multiple-comparison test). Plasma [Mg²⁺] was significantly lower on Mg²⁺-K⁺-deficient diet and on Mg²⁺-deficient diet compared with normal diet and K⁺-deficient diet (one-way ANOVA, Tukey’s multiple-comparison test). B: Western blot analysis of whole kidney lysates showed that long-term (14 days) dietary Mg²⁺ restriction downregulated total Na⁺-Cl⁻ cotransporter (tNCC) abundance compared with normal diet and K⁺-deficient diet (one-way ANOVA with Tukey’s multiple-comparison test). Long-term (14 days) dietary Mg²⁺ restriction also lowered pNCC abundance compared with normal diet, whereas pNCC abundance was not higher on K⁺-deficient diet (one-way ANOVA with Tukey’s multiple-comparison test). For blot quantification, densitometric values were normalized using Coomassie-stained gels. Values are means ± SE; values in parentheses indicate n values. *P < 0.05; **P < 0.001; ***P < 0.0001.