Salt loading affects cortisol metabolism in normotensive subjects: relationships with salt sensitivity

MN Kerstens, FGH van der Kleij… - The Journal of …, 2003 - academic.oup.com
MN Kerstens, FGH van der Kleij, AH Boonstra, WJ Sluiter, J Koerts, G Navis, RPF Dullaart
The Journal of Clinical Endocrinology & Metabolism, 2003academic.oup.com
We studied cortisol metabolism together with insulin sensitivity [homeostatic model
assessment (HOMA)] and renal hemodynamics in 19 salt-resistant (sr) and nine salt-
sensitive (ss) normotensive subjects after a low-and high-salt diet. Results are described as
high-vs. low-salt diet. Sum of urinary cortisol metabolite excretion (∑ metabolites) increased
in sr subjects (3.8±1.6 vs. 3.1±1.1 μg/min per square meter, P< 0.05) and decreased in ss
subjects (2.3±1.0 vs. 2.9±1.1 μg/min per square meter, P< 0.05). Plasma 0830 h cortisol …
We studied cortisol metabolism together with insulin sensitivity [homeostatic model assessment (HOMA)] and renal hemodynamics in 19 salt-resistant (sr) and nine salt-sensitive (ss) normotensive subjects after a low- and high-salt diet. Results are described as high- vs. low-salt diet. Sum of urinary cortisol metabolite excretion (∑metabolites) increased in sr subjects (3.8 ± 1.6 vs. 3.1 ± 1.1 μg/min per square meter, P < 0.05) and decreased in ss subjects (2.3 ± 1.0 vs. 2.9 ± 1.1 μg/min per square meter, P < 0.05). Plasma 0830 h cortisol decreased in sr subjects but did not change significantly in ss subjects. In all subjects, the absolute blood pressure change correlated negatively with the percentage change in ∑metabolites (P < 0.05) and positively with the percentage change in renal vascular resistance (P < 0.05). ∑metabolites during high-salt diet correlated negatively with the percentage changes in plasma 0830 h cortisol (P < 0.05) and renal vascular resistance (P = 0.05). HOMA did not change in either group, but the percentage change in HOMA correlated positively with the percentage change in plasma cortisol (P = 0.001) and negatively with the percentage change in ∑metabolites (P < 0.01). Parameters of 11β-hydroxysteroid dehydrogenase activity were not different between groups and did not change. In conclusion, these data suggest that cortisol elimination is affected differently after salt loading in sr and ss subjects. Changes in circulating cortisol might contribute to individual sodium-induced alterations in insulin sensitivity.
Oxford University Press