Explore the relationship between stress and the immune system. What is the HPA axis? What are stress hormones? Is there a "lab" test to measure stress levels in human beings?

What will be an ideal response?

Sample Answer: The activity of the endocrine system increases when we are stressed, primarily through activation of the hypothalamic-pituitary-adrenocortical (HPA) axis. Although a variety of neurotransmitters begin flowing in the nervous system, much attention has focused on the endocrine system's neuromodulators or neuropeptides, hormones affecting the nervous system that are secreted by the glands directly into the bloodstream. These neuromodulating hormones act much like neurotransmitters in carrying the brain's messages to various parts of the body. One of the neurohormones, corticotropin-releasing factor (CRF), is secreted by the hypothalamus and stimulates the pituitary gland. Farther down the chain of the HPA axis, the pituitary gland (along with the autonomic nervous system) activates the adrenal gland, which secretes, among other things, the hormone cortisol. Because of their close relationship to the stress response, cortisol and other related hormones are known as the stress hormones.The hypothalamus, at the top of the brain stem, is right next to the limbic system, which contains the hippocampus and seems to control our emotional memories. The hippocampus is responsive to cortisol. When stimulated by this hormone during HPA axis activity, the hippocampus helps to turn off the stress response, completing a feedback loop between the limbic system and the various parts of the HPA axis.This answer does not address the last part of the question regarding a "lab test" for stress levels.