ausblenden:
Schlagwörter:
Glucocorticoid feedback, Sleep EEG, Cortisol, ACTH, Fludrocortisone, Metyrapone, Depression
Zusammenfassung:
Nocturnal hyperactivity of hypothalamic-pituitary-adrenal axis (HPA)
indicates decreased feedback inhibition with stress-related conditions
such as major depression and sleep disorders. To characterize the role
of mineralocorticoid (MR) in regulation of HPA axis activity during
nocturnal sleep and involvement in sleep architecture, we investigated
sleep endocrine effects of the MR agonist fludrocortisone in healthy men
after pretreatment with metyrapone to minimize the impact of endogenous
cortisol. Subjects (n=8) were treated on three occasions in a
single-blinded design in random order with a) metyrapone, b)
fludrocortisone after metyrapone, and c) placebo. Polysomnography was
recorded and blood samples were drawn for determination of
adrenocorticotropic hormone (ACTH) and cortisol during the entire night.
After metyrapone administration ACTH was significantly enhanced, while
overall nocturnal cortisol secretion remained largely unchanged. Whereas
administration of fludrocortisone induced a significant inhibitory
effect on basal ACTH and cortisol secretion, no considerable effects on
sleep pattern were detectable. While the involvement of MR in sleep
regulation needs further study, endocrine findings underline the role of
MR in tonic regulation of HPA axis during nocturnal sleep and
demonstrate the ability of fludrocortisone to further suppress HPA axis
activity overnight. Additional studies would be required to evaluate
endocrine and clinical fludrocortisone effects in depressive patients
showing HPA hyperactivity. (C) 2015 Elsevier Ireland Ltd. All rights
reserved.
