Adrenal Gland and hormone

Question 1

Adrenal cortex

Answer 1

1. Zona glomerulosa - mineralcorticoids
2. Zona fasiculata - glucocorticoidss
3. Zona reticularis - weak androgens

Question 2

Mineralcorticoids

Answer 2

Aldosterone
1. Kidneys
• increases reabsorbtion of Na which in turn causes water reabsorbtion.
-> blood volume increases
-> blood pressure increases
• Stimulates kidneys to increase K+ and H+ secretion into urine

Question 3

RAAS system -

Answer 3

dehydration, sodium def, haemorrhage

1. Low blood volume
2. Low blood pressure
3. Juxtaglomerular cells in kidneys secrete enzyme renin
4. Renin converts angiotensinogen made by liver to angiotensin 1
5. Angiotensin 1 converted to ANGIOTENSIN II by ANGIOTENSIN CONVERTING ENZYME

Question 4

Effects of angiotensin II

Answer 4

• Stimulates aldosterone releaseby adrenal cortex

* Vasoconstriction of smooth muscles of arterioles

Question 5

Effects of glucocorticoids

Answer 5

Cortisol;

1. Proteinlysis and increase in amino acids in blood
2. Gluconeogenesis
3. Lipolysis
4. Anti inflammatory effects
5. Depress immune responses

Question 6

Control of glucocorticoid release

Answer 6

1. Low levels of cortisol in the blood stimulate hypothalamus to secrete CRH
2. ACTH released from anterior pituitary
3. Stimulates cortisol and aldoesterone and androgen release

Question 7

Androgens

Answer 7

ACTH stimulates release
• DHEA (dehydroepiandroosterone)
• Males get most androgens from testes
• Females especially after menopause rely on adrenal androgens

Question 8

Adrenal medulla

Answer 8

1. Chromaffin cells
   • innervated by sympathetic neurons of autonomic nervous system
   • Epinephrine (80%)
   • Norepinephrine (20%)

intensify sympathetic response in the body

Question 9

Effect of epinephrine and norepinehrine

Answer 9

• inc heart rate
• force of contraction
• inc blood pressure etc