DRKS00007768; Pre-results.

No abstract

Acute psychological stress of a first time parachute jump stimulated DHEA and cortisol secretion in healthy volunteers. A significant shift from cortisol to DHEA occurred during this stress exposure. This effect was more pronounced in subjects receiving the beta-adrenoceptor antagonist propranolol prior to the jump. In contrast, infusion of epinephrine (0.10 microgram/kg/min) or norepinephrine (0.15 microgram/kg/min) for 20 min neither affected DHEA plasma levels nor the DHEA/cortisol ratio. However, pretreatment with propranolol resulted in a significant increase of the DHEA/cortisol ratio upon infusion of the beta-adrenoceptor agonist epinephrine. These data demonstrate that during acute psychological stress stimulation of adrenal steroid release is accompanied by a shift towards DHEA. Augmentation of this effect by beta-adrenoceptor blockade indicates a beta-adrenoceptor-dependent mechanism affecting DHEA release.

No abstract

It is unknown whether plasma catecholamines have direct physiologic effects on pituitary-adrenocortical secretion in man. Therefore we investigated the effects of epinephrine and norepinephrine on plasma concentrations of adrenocorticotropin (ACTH), beta-endorphin and cortisol. Nineteen healthy male volunteers received infusions of either NaCl, epinephrine (0.10 micrograms/kg/min) or norepinephrine (0.15 micrograms/kg/min) for 20 minutes. 30 min before to 120 min after the infusion blood was continuously drawn to determine plasma levels of epinephrine, norepinephrine, and cortisol. In addition, ACTH and beta-endorphin plasma concentrations were analyzed at 6 time points before, during and after infusion. Infusion of catecholamines increased epinephrine and norepinephrine concentrations in physiological ranges as observed during intense psychological stress or exhausting physical exercise. However, these increases in catecholamine plasma levels neither affected concentrations of POMC-derived hormones nor plasma levels of cortisol. We conclude that in man, physiologic increases in circulating catecholamines have no influence on pituitary-adrenal hormone concentrations.