Endocrine Abstracts

Glucocorticoid hormones (cortisol in man, corticosterone in rodent; CORT) are vital for maintaining normal homeostasis in multiple systems ((e.g., the cardiovascular, metabolic, and immune systems), and for an optimal response to acute and chronic stress. Plasma CORT is released from the adrenal zona fasciculata (ZF) in response to circulating levels of pituitary-derived adrenocorticotropin hormone (ACTH). ACTH binds to the MC2-receptor on the membra...

Pharmacological treatment with synthetic glucocorticoids, which are widely prescribed for the treatment of numerous inflammatory and autoimmune diseases, can also affect the way the adrenal gland produces cortisol. Indeed, patients undergoing synthetic glucocorticoid treatment can develop adrenal insufficiency. This condition is characterised by reduced responsiveness of the adrenal to ACTH stimulation, and adrenal crisis/shock can occur in response to acute physiological stre...

Dexamethasone (DEX) is a widely used synthetic glucocorticoid whose effects are mediated via glucocorticoid receptor (GRs). Synthetic glucocorticoids are widely used in the clinical setting, due to their potent anti-inflammatory actions. However they are associated with numerous systemic side-effects and may also promote cognitive dysfunction, including impaired memory and learning processes in both patients and animal models.Discrete pulses of endogenou...

Background and case: A 38-year-old man presented acutely with left-sided retro-orbital pain, a heavy/numb sensation in his left arm and blurred vision and diplopia on left lateral gaze. Baseline biochemistry, liver function and haematology were normal. His TSH was 3.9 (0.3–4 mU/l) and CRP 92 mg/l (<10). Plain CT head was unremarkable as was the MRI as reported, and atypical migraine was suspected. Vertical diplopia on left lateral gaze and left upper arm paraesthesia ...

Two-way interactions between the hypothalamo–pituitary–adrenal (HPA) axis and the hypothalamo–pituitary–testicular (HPT) axis are well recognised. For example, in rats disruption of the HPT axis alters the circadian secretion of corticosterone. Conversely, stress conditions have varying effects on the level of testosterone secretion in both rats and humans. In contrast to humans, where several pulses of testosterone secretion can be detected across the 24 h...

Sleep and cortisol cycles have a complex inter-relationship that is not fully understood. Slow wave sleep appears to have an inhibitory effect on cortisol production but the effect of other stages is not so clear. From diseases, such as Addisons disease and Cushings syndrome, we know that cortisol levels have an impact on the quality of sleep. In insomnia and depression, both sleep and cortisol is altered.To investigate this relationship properly a minim...

IntroductionThe secretion of multiple hormones occurs in both a circadian and an ultradian manner. Both animal and human studies have shown that cortisol has an ultradian rhythm. Variations in ultradian cortisol secretion may explain inter-individual variation in the stress response.ObjectiveWe have developed an automated blood sampling system (ABS) that allows undisturbed sampling of blood, thus reducing str...

Control mechanisms of adrenocorticotrophic hormone (ACTH) and cortisol (CORT) secretion and metabolism during acute systemic inflammation (e.g. major surgery) have never been clearly elucidated. We sampled blood every 10 minutes for 12 h during and after coronary artery bypass grafting (CABG) in 10 patients to create profiles of ACTH, CORT and inflammatory mediators and compared these to healthy controls. Patients’ ACTH and CORT responses were classified into one of three...

In the clinic, glucocorticoids are widely used due to their anti-inflammatory properties. Despite their huge benefits, prolonged use is often associated with severe side effects as well as the development of glucocorticoid resistance in some cases. Mutations in an important SWI/SNF subunit, ARID1a, have previously been linked to glucocorticoid resistance and are associated with a vast number of human cancers. Determining the functional role of ARID1a...

The hypothalamic-pituitary-adrenal axis is the primary neuroendocrine system activated to establish homeostasis during the stress of critical illness and surgery. However, such critical states also trigger a systemic inflammatory activation that usually precedes the release of adrenocorticotrophic hormone (ACTH) and cortisol. Systemically or locally induced inflammation of the adrenal gland had been described during critical illness. This facilitates...