WAdrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions. Adrenaline is normally produced both by the adrenal glands and by a small number of neurons in the medulla oblongata. It plays an important role in the fight-or-flight response by increasing blood flow to muscles, output of the heart by acting on the SA node, pupil dilation response and blood sugar level. It does this by binding to alpha and beta receptors. It is found in many animals and some single-celled organisms. Polish physiologist Napoleon Cybulski first isolated adrenaline in 1895.
WAllostatic load is "the wear and tear on the body" which accumulates as an individual is exposed to repeated or chronic stress. The term was coined by Bruce McEwen and Stellar in 1993. It represents the physiological consequences of chronic exposure to fluctuating or heightened neural or neuroendocrine response which results from repeated or prolonged chronic stress.
WCortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone.
WThe cortisol awakening response (CAR) is an increase between 38% and 75% in cortisol levels peaking 30–45 minutes after awakening in the morning in some people. This rise is superimposed upon the late-night rise in cortisol which occurs before awakening. While its purpose is uncertain, it may be linked to the hippocampus' preparation of the hypothalamic-pituitary-adrenal axis (HPA) in order to face anticipated stress.
WThe effects of stress on memory include interference with a person's capacity to encode memory and the ability to retrieve information. During times of stress, the body reacts by secreting stress hormones into the bloodstream. Stress can cause acute and chronic changes in certain brain areas which can cause long-term damage. Over-secretion of stress hormones most frequently impairs long-term delayed recall memory, but can enhance short-term, immediate recall memory. This enhancement is particularly relative in emotional memory. In particular, the hippocampus, prefrontal cortex and the amygdala are affected. One class of stress hormone responsible for negatively affecting long-term, delayed recall memory is the glucocorticoids (GCs), the most notable of which is cortisol. Glucocorticoids facilitate and impair the actions of stress in the brain memory process. Cortisol is a known biomarker for stress. Under normal circumstances, the hippocampus regulates the production of cortisol through negative feedback because it has many receptors that are sensitive to these stress hormones. However, an excess of cortisol can impair the ability of the hippocampus to both encode and recall memories. These stress hormones are also hindering the hippocampus from receiving enough energy by diverting glucose levels to surrounding muscles.
WThe hypothalamic–pituitary–adrenal axis is a complex set of direct influences and feedback interactions among three components: the hypothalamus, the pituitary gland, and the adrenal glands.
WStress, either physiological, biological, or psychological is an organism's response to a stressor such as an environmental condition. Stress is the body's method of reacting to a condition such as a threat, challenge or physical and psychological barrier. Stimuli that alter an organism's environment are responded to by multiple systems in the body. In humans and most mammals, the autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis are the two major systems that respond to stress.
WThe universal stress protein (USP) domain is a superfamily of conserved genes which can be found in bacteria, archaea, fungi, protozoa and plants. Proteins containing the domain are induced by many environmental stressors such as nutrient starvation, drought, extreme temperatures, high salinity, and the presence of uncouplers, antibiotics and metals.
WWhy Zebras Don't Get Ulcers is a 1994 book by Stanford University biologist Robert M. Sapolsky. The book proclaims itself as a "Guide to Stress, Stress-Related Diseases, and Coping" on the front cover of its third and most recent edition.