Figure 2. Effects of high and low dietary Na⁺ intake on ENaC-mediated colonic Na⁺ transport and on the plasma aldosterone concentration (P_Aldo).

Similar experiments to those described in Fig. 1 were performed to determine the amiloride-sensitive I_SC component (ΔI_SC-Ami) in colon tissues from WT (open columns), +/L (hatched columns) and L/L animals (filled columns) exposed to a low salt or high salt diet. The ΔI_SC-Ami values for animals on a standard salt diet were calculated from the data shown in Fig. 1. Plasma aldosterone concentrations (P_Aldo) were determined in all groups of animals. In each dietary group, the mean ΔI_SC-Ami and P_Aldo values of the +/L and the L/L animals were compared to the corresponding values of the wild-type animals (*P < 0.05; **P < 0.01; ***P < 0.001; n.s., not significant).