Figure 6.

UPARANT effects on AQP2 expression and localization. (A) Representative blots showing protein levels of AQP2 in the kidney medulla. β‐actin was used as the loading control. (B) Densitometric analysis showing that UPARANT at 8 mg/kg increased high glucose‐induced AQP2 up‐regulation, while it was ineffective at 1 mg/kg (*P < 0.01 and **P < 0.001 vs control; ^§ P < 0.001 vs STZ; one‐way ANOVA followed by Newman‐Keuls’ multiple comparison posttest). Data are presented as scatter plots. Each plot represents the mean ± SEM of data from three independent samples. (C‐K) AQP2 immunoreactivity in control (C‐E) and STZ rats either untreated (F‐H) or treated with UPARANT 8 mg/kg (I‐K). Representative photomicrographs from sections that are representative of three animals/group showing that AQP2 is expressed at the apical plasma membrane of cells lining the collecting ducts of the cortex (C) and the medulla (outer in D and inner in E). STZ did not modify AQP2 expression in the cortex (F), whereas increased the apical expression of AQP2 in the medulla (outer in G and inner in H). UPARANT at 8 mg/kg did not change AQP2 expression in the cortex (I), whereas additionally increased AQP2 apical expression in the medulla (outer in J and inner in K). Scale bar: 50 μm