Hormones that affect short term and long term stress…

Adrenal Glands Located above each kidney Inner gland – adrenal medulla medulla surrounded by outer casing (adrenal cortex), regulated by the nervous system hormones regulate the adrenal cortex Adrenal medulla produces two hormones (produced when cells within adrenal medulla are stimulated by sympathetic nerves in times of stress Epinephrine (adrenaline) Norepinephrine (noradrenaline)

FIGHT OR FLIGHT!! These two hormones initiate fight-or-flight biological responses blood sugar level rises glycogen converted to glucose ensures greater energy reserve available increase heart and breathing rates as well as cell metabolism blood vessels dilate = allowing more oxygen and nutrients to reach tissues irises dilate http://www.youtube.com/watch?v=RyP8L3qTW9 Q

Adrenal Cortex Stimulated by other hormones- ACTH Produces three different types of hormones Glucocorticoids one of the most important - Cortisol, increases level of amino acids in blood and helps in recovery of stress by being converted to glucose in liver, supplying more energy needed for repair or recovery by cells or participating in protein synthesis Mineralocorticoids Salt and water balance – ALDOSTERONE! Sex hormones Small amounts!

Long Term Stress Response hypothalamus sends hormone to anterior lobe of pituitary stimulates pituitary to secrete corticotrophin (adrenocorticotropic hormone; ACTH) blood carries ACTH to target cells in adrenal cortex cells of adrenal cortex secrete mineralocorticoids and glucocorticoids (one of which is cortisol) these are carried to target cells in liver and muscles as cortisol levels rise, hypothalamus and pituitary production of regulatory hormones decreases eventually cortisol levels begin to fall

Effects of stress on a body Nerve signals Spinal cord (cross section) Hypothalamus Releasing hormone Nerve cell Anterior pituitary Blood vessel adrenal medulla secretes epinephrine & norepinephrine Nerve cell Adrenal cortex secretes mineralocorticoids & glucocorticoids ACTH Adrenal gland Kidney MEDULLA CORTEX (A) SHORT-TERM STRESS RESPONSE (B) LONG-TERM STRESS RESPONSE Effects of epinephrine and norepinephrine: 1. Glycogen broken down to glucose; increased blood glucose 2. Increased blood pressure 3. Increased breathing rate 4. Increased metabolic rate 5. Change in blood flow patterns, leading to increased alertness & decreased digestive & kidney activity Effects of mineralocorticoids: 1. Retention of sodium ions & water by kidneys 2. Increased blood volume & blood pressure Effects of glucocorticoids: 1. Proteins & fats broken down & converted to glucose, leading to increased blood glucose 2. Immune system suppressed