The aldosterone antagonist, spironolactone, impairs the ability of the kidney to lower the pH of the urine maximally during acute ammonium chloride loading. This action of spironolactone, which to our knowledge has not been previously reported, also implies that aldosterone may participate in the regulation of acid-base homeostasis in man.
Manuel MA, Beirne GJ, Wagnild JP, Weiner MW. An Effect of Spironolactone on Urinary Acidification in Normal Man. Arch Intern Med. 1974;134(3):472-474. doi:10.1001/archinte.1974.00320210082011