Pulsatile activation of the hypothalamic-pituitary-adrenal axis during major surgery

Evolution of Viral Hepatitis: Role of Psychosocial Stress

“…(Hinson JP. 1990;Calogero AE et al, 1992) Secreted glucocorticoids regulate T-helper-1 and 2 responses to viral infection by inhibiting the production of Interleukin 12 (IL-12) and Tumor Necrosis Factor Alpha (TNF Alpha). Several other interleukines (IL), such as IL-2 and cytokines IL-10 and IL-4 are stimulated through their actions.…”

Organization and Integration of the Endocrine System: The Arousal and Sleep Perspective

“…[34] In nonstressful situations, both CRH and AVP are secreted in the portal system in a circadian and highly concordant pulsatile fashion. [35][36][37][38][39][40] The amplitude of the CRH and AVP pulses increases in the early morning, resulting eventually in increases in the amplitude and apparent frequency of ACTH and in cortisol secretory bursts in the general circulation. The circadian release of CRH, AVP, ACTH, and cortisol in their characteristic pulsatile manner appears to be controlled by one or more pacemakers, whose location in humans is not known.…”

“…Also, with strong physical stress, recruitment takes place of AVP of magnocellular neuron origin that is secreted into both the hypophysial portal system through collateral neuraxons and the systemic circulation. [40,41] Depending on the stressor, other factors, such as angiotensin II, various cytokines, and lipid mediators of inflammation, are secreted and act on hypothalamic, pituitary, or adrenal components of the HPA axis, mostly to potentiate its activity.…”

“…[42,43] There is evidence that other hormones or cytokines, or both-either originating from the adrenal medulla or coming from the systemic circulation -or neuronal information from the autonomic nerves of the adrenal cortex may also participate in the regulation of cortisol secretion. [40,[44][45][46] Glucocorticoids are the final effectors of the HPA axis. These hormones are pleiotropic, and they exert their effects through their ubiquitously distributed intracellular receptors.…”

Effects of tourniquet-induced ischemia on the release of proopiomelanocortin derivatives determined in peripheral blood plasma

“…PROOPIOMELANOCORTIN (POMC) derivatives such as ␤-endorphin have been reported to be released into the cardiovascular system during physical exercise (10,20,22,27), which has been attributed to the stimulatory effect of elevated concentrations of lactate (3,21), acidosis (10,32), or an alteration of base excess (BE) (32). The pituitary is widely agreed to be the essential source of POMC derivatives, which have been determined in venous blood plasma in those studies.…”