Kaliuretic response to aldosterone: influence of the content of potassium in the diet

Am J Kidney Dis. 1993 Feb;21(2):152-60. doi: 10.1016/s0272-6386(12)81086-9.


The excretion of potassium (K+) decreased by 50% (30 v 63 mEq/d, P < .01) when subjects consumed a diet that was low in K+ for 3 days. Although part of this conservation of K+ was achieved in part by suppressing the release of aldosterone, nevertheless providing exogenous mineralocorticoids did not lead to a large kaliuresis when there was a modest degree of K+ depletion. Accordingly, the purpose of this study was to evaluate possible mechanisms for this antikaliuretic response to mineralocorticoids. The renal handling of K+ was examined by independent analysis of the two factors that influence its excretion, the driving force to secrete K+ and the urine volume. This driving force is reflected in a noninvasive fashion by the transtubular [K+] gradient (TTKG). Stimuli to increase the rate of excretion of K+ in subjects on a normal and a low-K+ diet included the administration of 200 micrograms fludrocortisone (9 alpha F), the induction of a high urine flow rate (9 alpha F+furosemide), the induction of bicarbonaturia (9 alpha F+acetazolamide), and the excretion of Cl(-)-poor urine (< 15 mEq/L). On the low-K+ diet, the peak value for the TTKG 3 to 4 hours after 9 alpha F was less than half that while on the normal diet (6.4 v 14, P < 0.01). In contrast, the TTKG was not significantly different on either diet when there was bicarbonaturia or the excretion of a Cl(-)-poor urine (18 v 17 and 17 v 16, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

MeSH terms

  • Acetazolamide / pharmacology
  • Adult
  • Aldosterone / metabolism*
  • Female
  • Fludrocortisone / pharmacology
  • Furosemide / pharmacology
  • Humans
  • Kidney / physiology*
  • Male
  • Potassium / urine*
  • Potassium Deficiency / physiopathology
  • Potassium Deficiency / urine*
  • Potassium, Dietary / administration & dosage*
  • Potassium, Dietary / pharmacology
  • Time Factors


  • Potassium, Dietary
  • Aldosterone
  • Furosemide
  • Acetazolamide
  • Potassium
  • Fludrocortisone