The Adrenal Glands Flashcards
Where are the adrenal glands located?
Above each kidney
Why do the adrenal glands release hormones?
In response to stress
What are the two different areas of the adrenal gland?
The adrenal medulla and cortex
What hormones does the adrenal cortex release ? and give a example
Glucocorticoids e.g. cortisol
Mineralcorticoids e.g. aldosterone
Sex steroids e.g. testosterone
What hormones does the medulla secrete?
Epinephrine and norepinephrine
What does Glucocorticoids do?
Regulates blood sugar
What does cortisol do?
Increases blood glucose and increases free fatty acids and suppresses inflammation
What dopes Mineralocortocids (aldosterone) do?
Increase K+ secretion and Na+ uptake by kidneys
What does Androgens (DHEA)do?
Influences secondary sexual characteristics and sexual behaviour
What does epinephrine/norepinephrine do?
Fight and flight response
What are the actions of cortisol?
Stimulates gluconeogenesis (formation of glucose from non carbohydrate sources) in response to low sugar/starvation
Protein breakdown and liberation of free fatty acids
Immune system suppression
Facilitated stress response
Maintains blood pressure
Maintains normal sleep/wake cycles
State the stages of the hypothalamic- pituitary-adrenal axis?
hypothalamus release CRF (corticotrophin releasing factor)-anterior pituitary release ACTH (adrenocorticotrophic hormone)-adrenal cortex release cortisol-increase of blood glucose and pressure and amino acids-negative feedback response that inhibits further release of CRF
Give three examples of medical uses of synthetic Glucocorticoids?
Eczema, Asthma and cancer therapy. (and many more)
Give three actions of adrenaline/Noradrenaline
Vasoconstriction,
Dilation of bronchi- increases oxygen,
Increases heart rate
Name the five triggers for the adrenal glands to produce adrenaline/Noradrenaline
Anxiety, pain, upright posture, exercise, cold
What are the three stages of the general adaptation syndrome (GAS)?
Alarm phase
Resistance phase
Exhaustion phase