AQP2 and Wilson disease: For this purpose, levels of total AQP2 and phosphorylated AQP2-S256,mediated by PKA, in the kidney of mice under 24 h of WD conditions were analyzed.Levels of total AQP2 and AQP2-S256 were significantly higher inArg-II−/− mice compared with WT controls, withoutsignificant difference in the ratio of AQP2-S256 to AQP2 (Fig. 6), which suggests that the cAMP/PKA pathway isnot regulated by Arg-II deficiency.