PURPOSE The use of morning basal serum cortisol levels as an alternative to dynamic testing for assessment of hypothalamic-pituitary-adrenal (HPA) axis has previously been reported. The purpose of this study was to determine the lower and upper cutoff values that would obviate subsequent HPA axis testing. METHODS A single-centre, retrospective study from a tertiary care endocrinology clinic w...

ACTH-induced-hypertension is commonly employed as a model of stress-related hypertension, and despite extensive investigation, the mechanisms underlying elevated blood pressure (BP) are not well understood. We have reported that ACTH treatment increases tail-cuff systolic pressure in wild-type mice but not in mutant mice expressing ouabain-resistant alpha(2)-Na(+)-K(+)-ATPase subunits (alpha2(R...

Pituitary ACTH drives adrenal glucocorticoid (cortisol) pulses via a time-delayed asymptotic dose-response process. To test the postulate that ACTH stimulates cortisol secretion dynamically (unequally during the initiation and termination of a cortisol secretory burst), a mathematical formalism was developed in which dose-response hysteretic shifts were allowed, but not required, within the tim...

BACKGROUND As supra-physiological intake of corticosteroids is a well known risk factor for the development of adrenal insufficiency, we investigated the function of the hypothalamic-pituitary-adrenal (HPA) axis during a 14-day course of systemic corticosteroids in patients with acute exacerbation of chronic obstructive pulmonary disease using clinical and laboratory measures. METHODS A syste...

BACKGROUND The hypothalamic-pituitary-adrenal (HPA) axis, and in particular cortisol, has been reported to be involved in obesity-associated metabolic disturbances in adults and in selected populations of adolescents. The aim of this study was to investigate the association between morning adrenocorticotropic hormone (ACTH) and cortisol levels and cardiovascular risk factors in overweight or ob...

The continuous 24-h infusion of a maximally stimulating dose (1 micrograms/kg per h) of ovine corticotropin-releasing factor (CRF) in man caused a modest elevation of plasma cortisol (17.2 +/- 1.4 micrograms/dl) and urinary-free cortisol (173 +/- 43 micrograms/24 h) concentrations, which was far less than that seen with a maximally stimulating dose of ACTH (50.4 +/- 2.2 micrograms/dl and 1,200 ...

OBJECTIVE A dose-response study with different doses of dexamethasone (dex) to assess the corticotrophic resistance in Cushing's disease (CD) using salivary cortisol as an end point has not yet been evaluated. We also reported our experience with salivary cortisol compared to plasma cortisol determination during dex suppression test (DST) and after ovine corticotrophin release hormone (oCRH) te...