Figure 4
Nedd4-2 mis-localization in PCK kidney is associated with increased apical ENaC and enhanced sodium reabsorption. (a) Kidneys from 12-week old strain control (Crj:CD/SD) (Wt); left) and PCK (right) rats immunostained for Nedd4-2 (red), Lamp1 (green) and DAPI (blue). Similar patterns were observed in sections from three different mutants, and abnormalities were restricted to collecting ducts. Scale bars, 20 μm. (b) Kidneys from 12-week old strain control (Wt) and PCK rats immunostained for each of the three subunits of ENaC (red), DBA (green) and DAPI (blue). Scale bars, 20 μm. (c) Primary CD cells from 12-week old strain control and PCK rats were isolated and cultured on Transwell filters and then immunostained for each of the three ENaC subunits (red) and DAPI (blue). Scale bars, 10 μm. (d) Open-circuit measurements of primary CD cells from three 12-week old strain control rats (Wt1, Wt2 and Wt3) and three PCK rats (PCK1, PCK2, PCK3) cultured on Transwell filters either in the absence or presence (“+Amil) of 50 μM amiloride in the apical side. Measurements were collected from at least 10 independent wells per animal. *P < 0.05, ** P < 0.01.
