Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Chapter Two: The Systems of the Body

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Brain : “the master gland” Interprets threat in the Cortex Hypothalamus: The 4 Fs (fight, flight, fear, sex) Pituitary: Releases hormones to start the stress response 2

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Hypothalamus: Corticotropin Releasing Factor (CRF) Pituitary: Vasopressin (Cardiac Response) Endorphins : Dulls Pain Perception Adrenals: Epinephrine (Adrenaline) Increases Blood Pressure Dilates Pupils and Blood Vessels Mobilizes Muscles to react 4

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Sympathetic Nervous System: Inhibits salivation Accelerate heartbeat Inhibits digestion Stimulates epinephrine (adrenaline) Stimulates arousal and orgasm Reproductive Hormones Suppressed Growth Hormones Suppressed Insulin Suppressed 5

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. 6 ( Source: Lankford, 1979, p. 232)

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Main Idea: Heart Overused Wears Out Increasing the force of fluid through vessels harm arteries: tears, scars, pits Atherosclerosis: fat deposits accumulate in the pits and tears Animal Studies: Stressed monkeys given betablockers, no plaques formed 7

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Angina Pain: Stress constricts not dilate blood vessels Damaged Cardiovascular system becomes over responsive to acute stressors Sudden Cardiac Death: Fibrillation/over- reactive heart is heart attack prone 8

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Huge Meal -> Insulin Pours out of pancreas to blood -> Fatty Acids go into fat cells -> Stimulate Glycogen and Protein Synthesis -> (Glycogen: strings of glycogen) 9

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Stress and Metabolism cont Stress -> Triggers Sympathetic NS Sympathetic NS -> Secrete Glucocorticoids Glucocorticoids blocks energy storage Leaves Glucose in blood available for energy Energy available for quick response: brain and muscles 10

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Sustained Stress -> Expend too much energy Fatigue (muscles do not repair) Diabetes Type II: Glucose builds up in blood vessels, Insulin not effective in storing glucose Glucose plaque in arteries:chronic pain/heart disease Necrosis in tissue: amputation danger Kidney damage (dialysis prone) Eye damage (danger of blindness) 11

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Chronic Stress: Glucocorticoids and Epinephrine: creates insulin ineffectiveness and instability 12

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Conditions to consider: Ulcer, Colitis, IBS Stress -> Shuts down digestion ->Reduces Acid Ulcer: Chronic Stress stomach lining not rebuilt -> walls of stomach thin out Prostaglandins rebuild but inhibited by stress -> H-Pylori Bacteria cause infections in the small holes in stomach walls 13

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Stress diverts energy away from digestion to brain and muscles: Large intestines empties and small intestines stop the absorption IBS: “spastic colon” too sensitive to stress Intestines stop and start erratically Constipation: small intestines stop erratically Diarrhea: large intestines empty erratically 14

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. CRF (Corticotropin Factor) hypothalamus Suppresses Appetite: short stressful events Stimulates Appetite: Glucocorticoids released during chronic stress after acute stressor resolves 15

Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Growth Hormones (Testosterone/Estrogen) Suppressed during Stress Neglect, Abuse, Insufficient Nurturance Overactive sympathetic system Dwarfism in children Recover if stress removed before Puberty Adulthood: Growth hormones repair cells Glucocorticoids block calcium/bone mass decreases 16

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Copyright © 2015 McGraw-Hill Education. All rights reserved. No reproduction or distribution without the prior written consent of McGraw-Hill Education. Acute Stress: Increase STM storage Chronic Stress: Glucocorticoids Reduce concentration Increase forgetting Hippocampus shrinks (permanent damage) Aging: Increased Glucocorticoids natural Severe stress and Aging: Speeds up aging and memory problems 18