CMB1004/L28 Adrenal Glands

Question 1

Describe the location of the adrenal glands anatomically.

Answer 1

Sit on top of each kidney

Question 2

What is the combined weight of adrenal glands in an adult?

Answer 2

8-10g

Question 3

What kind of hormones are produced in the cortex of the adrenal glands?

Answer 3

Steroid hormones

Question 4

What kind of hormones are produced in the medulla of the adrenal glands?

Answer 4

Amino acid hormones

Question 5

What kind of tissue is the adrenal cortex derived from?

Answer 5

Mesodermal tissue surrounding kidneys

Question 6

What kind of tissue is the adrenal medulla derived from?

Answer 6

Neural crest tissues

Question 7

What is the neurotransmitter of the sympathetic nervous system?

Answer 7

Norepinephrine

Question 8

Give the 3 ‘zones’ of the adrenal cortex, from inside-outwards.

Answer 8

Zona reticularis
Zona fasiculata
Zona glomerulosa

Question 9

What hormone is produced by the zona glomerulosa (outer layer)?

Answer 9

Aldosterone

Question 10

What hormone acts on receptors in zona glomerulosa?

Answer 10

Angiotensin II

Question 11

What hormones are produced by the zona fasiculata (middle layer)?

Answer 11

Cortisol and androgens

Question 12

What hormones are produced by the zona reticularis (inner layer)?

Answer 12

Cortisol and androgens

Question 13

What hormones are produced by the adrenal medulla?

Answer 13

Mostly epinephrine
Some pre-methylated noradrenaline

Question 14

What enzyme is lacked in the zona glomerulosa?

Answer 14

17 alpha-hydroxylase

Question 15

What kind of molecule is aldosterone?

Answer 15

Mineralocorticoid

Question 16

What is the half-life of aldosterone?

Answer 16

15-20 minutes

Question 17

What is the function of aldosterone?

Answer 17

On kidney, colon and salivary glands
Maintains normal Na+ concentration and extracellular fluid volume

Question 18

Describe the action of aldosterone. (3)

Answer 18

Binds to mineralocorticoid receptors within principal cells
Upregulates ENaC
Upregulates and activates Na+/K+ ATPase

Question 19

What is the Na+ reabsorption with and without aldosterone?

Answer 19

Without: 98%
With: >99.6%

Question 20

What hormone is cleaved by renin to form angiotensin I?

Answer 20

Angiotensinogen

Question 21

What molecule forms angiotensin II from angiotensin I?

Answer 21

ACE

Question 22

What organs does angiotensin II work on? (3)

Answer 22

Vasculature
Hypothalmaus
Adrenal glands (cortex)

Question 23

What enzyme is lacked in the zona fasiculata and zona reticularis?

Answer 23

CYP11B2 gene
P450aldo

Question 24

What kind of molecule is cortisol (hydrocortisone)?

Answer 24

Glucocorticoid

Question 25

What is the half-life of cortisol?

Answer 25

60-90 minutes

Question 26

Give 2 effects of cortisol on glucose metabolism.

Answer 26

Stimulates hepatic gluconeogenesis Inhibits glucose uptake in muscle and adipose tissue

Question 27

What effect does cortisol have on muscle catabolism?

Answer 27

Stimulation of muscle catabolism

Question 28

Give 3 effects of cortisol, NOT including glucose metabolism.

Answer 28

Inhibits bone formation Leads to loss of collagen and connective tissue Increases vascular sensitivity to epinephrine and norepinephrine Can modulate behaviour and cognitive function Inhibits gonadal release of testosterone, oestrogen and progestins

Question 29

How do glucocorticoids produce anti-inflammatory and immunosuppression effects? (2)

Answer 29

Inhibits cytokine production and T cell proliferation Inhibits prostaglandin and leukotriene production

Question 30

Which part of the adrenal glands will respond to adrenocorticotropic hormone?

Answer 30

Zona fasiculata Zona reticularis

Question 31

What is the affinity of cortisol for mineralocorticoid receptors in relation to aldosterone?

Answer 31

100x more

Question 32

What enzyme prevents the mineralocorticoid effects of cortisol being greater?

Answer 32

11 beta-hydroxysteroid dehydrogenase in aldosterone responsive cells