HPA-axis Hypothalamus, pituitary gland and cortex of adrenal gland. Responsible for stress response, elicited by the encounter of an aversive stimulus, interpreted as potentially harmful for the individual.. The release of CRF (corticotrophin releasing factor) by the hypothalamus prompts the pituitary to disperse adrenocorticotropin-releasing hormone (ACTH) into the bloodstream. ACTH is detected by the adrenal cortex, facilitating the release of glucocorticoids such as cortisol. Negative feedback of cortisol on the hypothalamus and pituitary, suppressing the subsequent release of CRF and ACTH.. From class: cortisol increases metabolic glucose, activated the immune system and the body is more ready to respond