Both physical and emotional stress activate several neuroendocrine systems, the most important being the hypothalamic-pituitary-adrenal axis that stimulates the production and secretion of glucocorticoids (especially cortisol) from the adrenal cortex. Therefore, cortisol is considered to be a "stress hormone" and higher levels of serum cortisol have been observed in patients with acute stress such as those presented with acute MI, compared to healthy controls.