Effect of amiloride and spironolactone on renal tubular function, ambulatory blood pressure, and pulse wave velocity in healthy participants in a double-blinded, randomized, placebo-controlled, crossover trial.

We wanted to test the hypothesis that treatment with amiloride or spironolactone reduced ambulatory (ABP) and central blood pressure (CBP) and that tubular transport via ENaCγ and AQP2 was increased after furosemide treatment. During baseline conditions, there were no differences in ABP, CBP, renal tubular function, or plasma concentrations of vasoactive hormones. After furosemide treatment, an increase in CBP, CH(2)o, FE(Na), FE(K), u-AQP2/min, u-ENaCγ/min, PRC, p-Ang II, and p-Aldo was observed. The increases in water and sodium absorption via AQP2 and ENaC after furosemide treatment most likely are compensatory phenomena to antagonize water and sodium depletion.