Glycyrrhetinic Acid Decreases Plasma Potassium Concentrations in Patients with Anuria

Andreas Serra, Dominik E. Uehlinger, Paolo Ferrari, Bernhard Dick, Brigitte M. Frey, Felix J. Frey, Bruno Vogt
2002 Journal of the American Society of Nephrology  
ABSTRACT. Licorice-associated hypertension is thought to be due to increased renal sodium retention. The active compound of licorice, glycyrrhetinic acid (GA), inhibits renal 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) and by that mechanism increases access of cortisol to the mineralocorticoid receptor that causes renal sodium retention and potassium loss. In addition, a direct vascular effect of 11β-HSD activity has recently been incriminated to promote hypertension, a contention based
more » ... a contention based on in vitro observations. This investigation was designed to establish whether this extrarenal effect of 11β-HSD is relevant for BP regulation and potassium concentrations in plasma. In a prospective, double-blind, cross-over study, seven patients with anuria on chronic hemodialysis were randomly assigned after a baseline period of 2 wk to placebo or GA (1 g/d) for 2 wk, separated by a washout phase of 3 wk. The ratio of plasma cortisol/cortisone, determined by gas chromatography–mass spectrometry, increased in all patients after GA intake (F = 9.705; P < 0.004), which indicates inhibition of 11β-HSD. Twenty-four–hour BP values did not change throughout the study. The increase of the plasma cortisol/cortisone ratio was paralleled by a decline in the plasma potassium concentration in every patient. The mean ± SD plasma potassium concentration decreased from 5.5 ± 0.6 mM/L at baseline to 4.9 ± 0.7 and 4.5 ± 0.8 mM/L after 1 and 2 wk on GA, respectively (F = 9.934, P < 0.003). Extrarenal 11β-HSD activity influences serum potassium concentrations but does not regulate BP independently of renal sodium retention.
doi:10.1681/asn.v131191 fatcat:5me2j7zsgfdk3cpjbx7lxigzka