Cortisol

Question 1

What are alpha 1 receptors?

Answer 1

adrenergic receptors in blood vessels
G protein coupled receptors
allow vasoconstriction of vessels when cortisol is present

Question 2

What is an adenoma?

Answer 2

A benign tumour formed from glandular structures in epithelial tissue.

Question 3

What are the 4 causes of Cushing’s syndrome?

Answer 3

exogenous steroids
primary adrenal adenoma
ACTH secreting pituitary adenoma
ectopic ACTH secretion eg. small cell carcinoma of lungs

Question 4

How do we do a suppression test?

Answer 4

Give a high dose of dexamethasone.

In ‘normal’ people it will suppress cortisol production.

Question 5

Define Cushing’s syndrome

Answer 5

Hyperactivity of the adrenal cortex producing increased cortisol levels.

Question 6

Define Cushing’s disease

Answer 6

Cushing’s syndrome resulting specifically from a pituitary tumour secreting ACTH.

Question 7

Name 2 effects of corticosteroids

Answer 7

immunosuppressive

impaired healing

Question 8

Define hirsutism

Answer 8

Excessive hairiness on women in those parts of the body where terminal hair does not normally occur.

Question 9

Name the main features of Cushing’s

Answer 9

moon face
buffalo hump
hyperglycaemia 
menstrual disturbance
osteoporosis
tendency to infections
hypertension
central obesity 
purple striae
muscle wasting

Question 10

What things do we measure when diagnosing Cushing’s?

Answer 10

plasma cortisol level
plasma ACTH level
urinary excretion of degradation products of glucocorticoids

Question 11

How does Cushing’s change the histology of the cortex?

Answer 11

cells will appear depleted in lipid

indicating that they have discharged their secretions

Question 12

Define neoplasm

Answer 12

An abnormal growth of tissue, usually forms a mass (tumour), but not always.

Question 13

What is Addison’s disease?

Answer 13

An insufficient level of cortical hormones in the plasma. Predominantly a decreased plasma cortisol level.

Question 14

What are the main signs of Addison’s?

Answer 14

weight loss
weakness
hypotension
hyperpigmentation 
Hyponatraemia  
dehydration

Question 15

When and how would we perform a ACTH stimulation test?

Answer 15

when diagnosing Addison’s
give Synacthen (synthetic ACTH analogue) which will increase plasma cortisol levels in ‘normal’ people
if cortisol levels are not increased then it may be Addison’s

Question 16

What are the actions of mineralocorticoids?

Answer 16

increase salt and water reabsorption

decrease potassium reabsorption

Question 17

Why would excess mineralocorticoids cause hypertension?

Answer 17

increased sodium reabsorption
increases water retention in blood
increased pressure due to higher blood volume

Question 18

What are the features of glucocorticoid deficiency?

Answer 18

low glucose
weight loss
nausea
hypotension

Question 19

What are the features of glucocorticoid excess?

Answer 19

weight gain
high glucose
increased appetite 
hypertension
Cushingoid

Question 20

What is the ACTH precursor?

Answer 20

POMC

Question 21

If you suspected Cushing’s, when would you measure cortisol?

Answer 21

at midnight when it is supposed to be its lowest

Question 22

What is Addison’s usually caused by?

Answer 22

autoimmune destruction of adrenal cortex

Question 23

What is the treatment for Addison’s?

Answer 23

hydrocortisone (replace glucocorticoids)

fludrocortisone (replace mineralocorticoids)

Question 24

What is the most common cause of Cushing’s?

Answer 24

Pituitary source

Question 25

When can Nelson’s syndrome occur and what is it?

Answer 25

after an adrenalectomy

lack of negative feedback causes uncontrolled pituitary growth

Question 26

What are the roles of cortisol?

Answer 26

maintain blood pressure
bone formation inhibition
anti-inflammatory (inhibits histamine release)
decreases immune function
increases gluconeogenesis, lipolysis and proteolysis