Urinary cortisol is inversely associated with capillary recruitment in women: a potential explanation for the cortisol-blood pressure relationship

Renate T de Jongh (1) , Richard G Ijzerman , Erik H Serné , Mirjam M van Weissenbruch , Jasper J Voordouw , Henriette A Delemarre-van de Waal , Coen Da Stehouwer

1 Department of Internal Medicine and Institure for Cardiovascular Research-Vrije Universiteit

The relationships of cortisol with elevated blood pressure and insulin resistance are likely to be the result of a complex interplay of different mechanisms. We hypothesized that cortisol is associated with microvascular dysfunction and that this contributes to cortisol-associated high blood pressure and insulin resistance. We examined 24h urinary free cortisol excretion in 56 healthy adults (26 women). Blood pressure was assessed by 24h ambulatory measurements. Insulin sensitivity was determined by the hyperinsulinaemic euglycaemic clamp technique. Skin capillary recruitment after arterial occlusion was visualized with videomicroscopy and endothelium-(in)independent vasodilation was evaluated with iontophoresis of acetylcholine and sodium nitroprusside combined with laser Doppler fluxmetry. Men were characterized by higher urinary cortisol excretion (median (interquartile range), 162 (130-194) vs. 118 (99-156) nmol/24h, P<0.05). In women, but not in men, urinary cortisol excretion was associated with capillary recruitment (r=-0.66, P<0.001), systolic blood pressure (r=0.64, P<0.001) and insulin sensitivity (r=-0.43, P<0.05). Urinary cortisol excretion was not associated with endothelium-(in)dependent vasodilation in men or women. Regression analysis demonstrated that capillary recruitment statistically explained 37% of the association between urinary cortisol and blood pressure in women. Capillary recruitment did not explain part of the association between urinary cortisol and insulin sensitivity. In conclusion, urinary cortisol excretion is associated with capillary recruitment in women, but not in men, and explains part of the cortisol-blood pressure relationship. These data suggest that, in women, impairment of capillary function mediates some of the adverse effects of cortisol and thus provides a target to prevent such adverse effects.

Mots clés: Medicine

Renate T de Jongh, Richard G Ijzerman, Erik H Serné, Mirjam M van Weissenbruch, Jasper J Voordouw, et al.. Urinary cortisol is inversely associated with capillary recruitment in women: a potential explanation for the cortisol-blood pressure relationship. Clinical Science, 2007, 113 (2), pp.83-91. ⟨10.1042/CS20060357⟩. ⟨hal-00479357⟩