Figure 4. Impaired reabsorption of Ca²⁺ and Cl⁻ in Cldn4^−/− mice.

(A) Indicated ion concentrations in the urine and serum of WT (open columns) and Cldn4^−/− (gray columns) mice (3 months old) with no evidence of hydronephrosis were analyzed, and the serum ion concentrations, creatinine (Cre), blood urea nitrogen (BUN), creatinine clearance (C_cre), and ion fractional excretions (FE) were determined. The means and SE of five mice are indicated. n.s., not significant; *p<0.05; **p<0.01. (B) Total 24-hour urine volume and osmolality of WT (open columns) and Cldn4^−/− (gray columns) mice before and after the water depletion for 24 hours were determined. The means and SE of five mice. n.s., not significant; *p<0.05; **p<0.01.