Causes adrenal glands to secrete adrenaline and noradrenaline.
This causes an increase in heart rate and increased rate of glucose metabolization
Hypothalamus also causes the release of corticotrophin-releasing hormone (CRH), which stimulates pituitary gland.
Pituitary then secretes adrenocorticotrophic hormone (ACTH) which causes adrenal cortex to produce stress hormone cortisol.
Cortisol prepares body for fight or flight.
Allostatic load—biological cost of adapting to stress
Allostatic load—biological cost of adapting to stress
Hans Selye (1936) General Adaptation Syndrome (GAS)
1) First stage—alarm reaction—fight or flight—autonomic nervous system activates
2) If stressor ends, ANS calms down. If it persists or new ones are added, alarm is followed by a stage of resistance.
3) If stressors continue, state of exhaustion begins as a result of long-term resistance. Physical signs: indigestion, loss of wt., insomnia, fatigue. Psychological signs: violence, delusions, stupor. May result in death.
Experiencing alarm—heightened vigilance and concentration; dizziness, light-headedness, shakiness
Experiencing alarm—heightened vigilance and concentration; dizziness, light-headedness, shakiness
Prolonged stress—release of stress hormones can cause chronically high b.p., damage muscle tissues and inhibit healing after injury
Innate immunity—1st line of defense; skin, mucus membranes
Specific immunity—acquired rather than innate
Detection
Destruction
Once battle is over, suppressor T cells call a halt, if not, body turns on itself.