Session 9

Question 1

Where are the adrenal glands?

Answer 1

They cap the upper poles of the kidneys and lie against the diagphragm in the retroperitoneal space

Question 2

What is the structure of the adrenal glands?

Answer 2

2 regions - outer cortex and inner medulla

Question 3

What is the outer cortex made up of?

Answer 3

Zone glomerulosa, zone fasiculata and zone reticularis

Question 4

What is excreted from the zone glomerulosa?

Answer 4

Mineralocorticoids eg aldosterone

Question 5

What is secreted from the zone fasiculata?

Answer 5

Glucocorticoids eg cortisol

Question 6

What is secreted from the zone reticularis?

Answer 6

Secreted glucocorticoids and small amounts of androgens (dehydroepiandosterone)

Question 7

What is the medulla made up of?

Answer 7

Chromaffin cells that produce adrenaline (80%) and noradrenaline (20%)

Question 8

What is the cortex derived from?

Answer 8

Mesoderm

Question 9

What is the medulla derived from?

Answer 9

Neural crest cells

Question 10

What is outside the adrenal cortex?

Answer 10

Connective tissue capsule which contains plexus of blood vessels

Question 11

What is a corticosteroid?

Answer 11

Any group of steroid hormone produced in adrenal cortex

Question 12

What are the key features of steroid hormones?

Answer 12

Synthesised from cholesterol, lipid soluble

Question 13

How do steroid hormones work?

Answer 13

They bind to nuclear receptors to modulate gene transcription

Question 14

Examples of steroid hormones?

Answer 14

Glucocorticoids, mineralocorticoid, androgens, oestrogens

Question 15

What is the most abundant mineralocorticoid?

Answer 15

Aldosterone

Question 16

Where is aldosterone synthesised and released from?

Answer 16

Zona glomerulosa of adrenal cortex

Question 17

What is the carrier proteins for steroid hormones?

Answer 17

Albumin

Question 18

How does aldosterone exert its effects?

Answer 18

Experts its actions by regulating gene transcription

Question 19

What is the most abundant corticosteroid?

Answer 19

Cortisol

Question 20

Where is cortisol synthesised and released from?

Answer 20

Zone fasiculata in response to ACTH

Question 21

What is the carrier proteins in plasma?

Answer 21

Transcortin

Question 22

How does the cortisol receptor exert its actions?

Answer 22

By regulating gene transcription

Question 23

Why do all steroid hormones need to be bound to plasma proteins when travelling in the blood?

Answer 23

Because steroid hormones are lipophilic

Question 24

What are the effects of cortisol?

Answer 24

Inc protein breakdown in muscle
Inc gluconeogenesis
Inc lipolysis in fat 
Dec peripheral uptake of glycolysis 
Dec immune response

Question 25

What can chronic high levels of cortisol result in?

Answer 25

Redistribution of fat especially in the abdomen, subclavicular fat pads and dorsal-cervical fat pad and on the face

Question 26

How does cortisol affect glucose uptake?

Answer 26

Cortisol inhibits GLUT4 translocation in muscles therefore preventing glucose uptake

Question 27

What does the hypothalamic-pituitary-adrenal axis do?

Answer 27

Regulates cortisol secretion

Question 28

What does ACTH stand for?

Answer 28

Adrenocorticotropic hormone

Question 29

What is ACTH?

Answer 29

Single chain polypeptide hormone

Question 30

What is the initial precursor of ACTH?

Answer 30

POMC - large protein

Question 31

How is ACTH released?

Answer 31

Released in circadian rhythm

Question 32

What are the features of ACTH?

Answer 32

Hydrophillic and interacts with high affinity receptors on the surface of cells in the zone fasiculata and reticularis

Question 33

What is the function of ACTH?

Answer 33

Causes conversion of cholesterol esters to free cholesterol.

Question 34

What happens if you get too much aldosterone produced?

Answer 34

Hyperaldosteronism

Question 35

What are the different types of hyperaldosteronism?

Answer 35

Primary and secondary

Question 36

What happens in primary aldosteronism?

Answer 36

Defect in the adrenal cortex caused by hyperactivity on or both adrenal glands.

Question 37

What is a diagnostic feature of primary hyperaldosteronism?

Answer 37

Low renin levels but no decrease in aldosterone levels. (High aldosterone:renin ratio).

Question 38

What is the cause of secondary hyperaldosteronism?

Answer 38

Overactivity of RAAS.

Question 39

What is the diagnostic feature of hyperaldosteronism?

Answer 39

High renin levels (low aldosterone:renin ratio)

Question 40

What are the signs of hyperaldosteronism?

Answer 40

High blood pressure, left ventricular hypertrophy, stroke, hypernatraemia and hyperkalaemia.

Question 41

What is the treatment for hyperalsoteronism?

Answer 41

Depends on type