Session 9- The adrenal gland

Question 1

What hormones are secreted from the cortex

Answer 1

Mineralocorticosteroids- aldosterone

Glucocorticoids- cortisol

Sex steroids- testosterone

Question 2

What hormones are released from the medulla

Answer 2

Adrenaline
Noradrenaline
Dopamine

Question 3

What is Cushing syndrome

Answer 3

Chronic excessive exposure to cortisol

Question 4

What is the external cause of Cushing

Answer 4

Prescribed glucocorticoids which is the most common cause

Question 5

What are the endogenous causes of Cushing syndrome

Answer 5

• Cushing’s disease
• adrenal cushings
• Non pituitary-adrenal tumours producing ACTH

Question 6

What is cushings disease

Answer 6

Benign pituitary adenoma secreting ACTH

Question 7

What is adrenal cushings

Answer 7

Excess cortisol produced by adrenal tumour

Question 8

What are the signs and symptoms of cushings

Answer 8

• Plethoic
• moon shaped face
• abdominal obesity
• purple striae
• acute weight gain
• hyperglycaemia
• hypertension

Question 9

What is the main steroid drug used

Answer 9

Prednisolone- synthetic glucocorticoid

Question 10

What is prednisolone used to treat

Answer 10

ed to treat inflammatory disorders e.g.
• Asthma
• Inflammatory bowel disease
• Rheumatoid arthritis
• Other auto-immune conditions

Question 11

What are the net effects of glucocorticoids

Answer 11

Increased glucose production

Breakdown of protein

Redistribution of fat

Question 12

What are the consequences of redistribution of fat

Answer 12

Higher levels of fat in abdomen

Supraclavicular fat pads

Dorsocervicual fat pads- buffalo hump

Moon face

Question 13

How do you distinguish between the different causes of raised cortisol

Answer 13

If there’s elevated ACTH- thus indicates a ACTH dependant cause- then do a Dexamthasone test

• if suppressed- cushings disease
• if not- ectopic tumours producing ACTH

If there’s suppressed ACTH- ACTH independent- ask if they take glucocorticoids if yes- exogenous cushings, if no- excess cortisol produced by adrenal tumour

Question 14

What is addisonians crisis

Answer 14

Life threatening emergency due to adrenal insufficiency

Question 15

What triggers addisononian crisis

Answer 15

• Severe stress
• Salt depravation
• Infection
• Trauma
• Cold exposure
• Over exertion
• Abrupt steroid drug

Question 16

Treatment of addisonian crisis

Answer 16

Fluid replacement and cortisol

Question 17

Symptoms of addisonian

Answer 17

Nausea
Vomiting 
Pyrexia 
Hypotension 
Vascular collapse

Question 18

What is produced in the zona glomerulosa

Answer 18

Salt

Mineralcorticosteroids- aldosterone

Question 19

What is produced in the zona fasciculata

Answer 19

Glucocorticoids - cortisol
Cortisone

Sugar

Question 20

What is produced in the zona reticularis

Answer 20

Glucocorticoids and small amounts of androgens
-dehydroepiandrosteone
-androstenedione which is converted to testosterone and oestrogen
Sex

Question 21

Order of layers of adrenal cortex

Answer 21

GFR

Glomerulosa
Zona fasiculata
Reticularis

Question 22

What are steroid hormones produced from

Answer 22

Cholesterol

Lipi soluble

Question 23

How to steroid hormones interact

Answer 23

Bind to receptors of the nuclear receptor family to modulate gene transcription

• glucocorticoids
• mineralocorticoids
• androgens
• oestrogen
• progestins

Question 24

How do corticosteroids exert their actions

Answer 24

They regulate gene transcription

• they readily diffuse across plasma membrane and bind to glucocorticoids receptors.
• binding causes dissociation of chaperone proteins
• receptor ligand complex translocates to nucleus
• dimerisation with other receptors can occur

Question 25

What is the carrier protein for aldosterone

Answer 25

Serum albumin and to a lesser extent transcortin

Question 26

What is the role of aldosterone

Answer 26

It promotes expression of the Na/K pump in the collecting ducts and distal tubules of the nephron which promotes reabsorption of Na+ and excretion of K+ thereby influencing water retention, blood volume and therefore blood pressure

Question 27

How can you distinguish between primary and secondary hyperaldosteronism

Answer 27

Primary- low renin high aldosterone:renin ratio Secondary -high renin low aldosterone:renin ratio

Question 28

What is primary hyperaldoseronism

Answer 28

Defect in adrenal cortex

Question 29

What can cause primary hyperaldosteronism

Answer 29

Bilateral idiopathic adrenal hyperplasia Aldosterone secreting adrenal adenoma - Conn’s syndrome

Question 30

What is secondary hyperaldosteronism

Answer 30

Due to over activity of RAAS

Question 31

What an cause secondary hyperaldosteronism

Answer 31

Renin producing tumour-rare Renal artery stenosis

Question 32

Signs of hyperaldosteronism

Answer 32

High BP Left ventricular hypertrophy Stroke Hypernatraemia Hypokalaemis

Question 33

Carrier protein in plasma for cortisol

Answer 33

Transcortin

Question 34

Actions of cortisol

Answer 34

``` Increased proteolysis in muscle Increased lipolysis Increased gluconeogeneis in liver Resistance to stress Anti-inflammatory effects Depression of immune system ```

Question 35

What is Addison’s disease

Answer 35

Chronic adrenal insufficiency Destructive atrophy from autoimmune response

Question 36

Signs and symptoms of addisons

Answer 36

Postural hypertension Lethargy Weight loss Anorexia Increased skin pigmentation Hypoglycaemia

Question 37

Why does Addisons cause hyperpigmentation

Answer 37

Decreased cortisol Negative feedback on ant pituitary More POMC required to synthesis ACTH POMC is used to make MSH therefore more melanin ACTH itself can also activate melanocortin receptors so melanocytes will also contribute

Question 38

What receptors in the heart increase heart rate and contractility

Answer 38

Beta 1

Question 39

Wha receptors cause bronchodilation

Answer 39

B2

Question 40

What receptors cause vasoconstriction in blood vessels in tthe skin and gut

Answer 40

A1

Question 41

What receptors cause vasodilation in blood vessels in skeletal muscle

Answer 41

B2

Question 42

What is phaechromocytoma

Answer 42

Chromaffin cell tumour - rare catecholamine secreting tumour - mainly noradrenaline Phaeo-dark Chromo-colour Cyte-cell Oma-tumour

Question 43

symptoms of phaeochromocytoma

Answer 43

Severe hypertension Headaches Palpitations Diaphoresis Anxiety Weight loss Elevated blood glucose

Question 44

What is the difference between cushings disease and syndrome

Answer 44

Cushing's syndrome refers to the general constellation of symptoms resulting from chronic excessive exposure to cortisol whereas Cushing’s disease refers to the specific case of a benign ACTH secreting pituitary adenoma. Cushing's syndrome is much more common than Cushing's disease.

Question 45

How do you investigate adrenocortical function- cushings

Answer 45

Measure plasma cortisol and ACTH levels and 24hr urinary excretion of cortisol and its breakdown products Dexamthasone suppression test and ACTH stimulation test

Question 46

What is Dexamthasone test

Answer 46

Dexamthasone is a Potent synthetic steroid that when given orally will suppress the secretion of ACTH and then therefore cortisol Suppression dozens occur in adrenal tumours or ectopic ACTH production

Question 47

How would you investigate Addison’s disease

Answer 47

Administration of synacthen- synthetic analogue of ACTH- intramuscularly which would normally increase plans cortisol. If normal excludes Addison