Figure 6.

The stimulatory effect of PGE₂ upon ENaC activity is preserved in cells pretreated with aldosterone. The left panel shows representative I_SC recordings in which vehicle (control; dashed line) or aldosterone (3 nM; solid line) were added bilaterally at the time point indicated by an arrow. Approximately 2 h later, cells were exposed to 100 nM basolateral PGE₂ and subsequently to apical amiloride (Ami; 10 µM) as indicated. Summary data (right panel) are presented as ΔI_SC values, which were determined by subtracting the corresponding baseline I_SC from the I_SC reached in the presence (+) or absence (−) of aldosterone and PGE₂ as indicated. Data are presented as individual values and their mean ± SEM. Paired data are connected by dashed lines. Numbers of experiments are given in parentheses. ***, P < 0.001, paired Student’s t test.