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Pharmacodynamics, Semester 2 > Corticosteroids > Flashcards

Flashcards in Corticosteroids Deck (20)
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1

Corticosteroids derive from which organic molecule?

Cholesterol

2

What can steroid hormones form

Sex hormones
Corticosteroid hormones

3

What are the two types of corticosteroid hormones?

Glucocorticoids and mineralcorticoids

4

What do glucocorticoids do and give an example

They have a role in regulation of glucose metabolism and synthesis.

Cortisol:
Decrease carbohydrate uptake and ultilisation
Increased protein metabolism
Regulatory effects on host defence mechanisms

5

What do mineralcorticoids do and give an example

They link to water and salt balances

Aldosterone:
Regulate water and electrolyte balance

6

Where are BOTH glucocorticoids and mineralocorticoids produced?

Adrenal glands

7

Where are mineralocorticoids synthesised?

Zona glomerulosa (outermost layer on adrenal cortex)

8

Where are glucocorticoids synthesised?

Zona fasciculata (middle layer on adrenal cortex)

9

How are corticosteroids regulated?

They are under the control of the hypothalamic-pituitary- adrenal (HPA) axis

10

What is Cushing's syndrome and what are the symptoms for it?

When there is overactivity and exposure to excessive levels of endogenous glucocorticoids

The symptoms are:
Hypertension
Easy bruising
Increased abdominal fat
Thinning of skin and thin arms and legs
Osteoporosis
Avascular necrosis of femur

11

What is Addison's disease?

When there is adrenal insufficiency

12

How does dimerisation of the receptors lead to the inhibition of transcription?

After the dimerisation of the receptors, they bind to the recognition site on DNA
The dimerisation of the receptors binds to the nGRE, repressing the activity of transcription factors which inhibits transcription

13

Glucocorticoids can also silence proinflammatory genes. What is this called?

Gene transrepression

14

How do glucocorticoids silence proinflammatory genes?

The receptors bind to the TFs Fos and Jun which inhibit transcription of AP-1.
This means there is less response to cytokines, growth factors, stress and bacterial and viral infections

15

Which specific pathway silences proinflammatory genes?

The NKkB pathway

16

Where are glucocorticoids absorbed and metabolised?

They are readily absorbed in the gut
They are extensively metabolised in the gut wall and liver

17

How do hydrocortisones bind in the blood?

Hydrocortisone binds to:
-corticosteroid binding globulin (transcortin)
-albumin in the blood

18

What are the pharmacokinetics of synthetic glucocorticoids?

Only bind to albumin and are more slowly metabolised in the liver

19

How are glucocorticoids usually administered?

Usually tropical to deliver high concentration

20

What are the side effects of glucocorticoid therapy?

Suppression of the response to infection or injury
Cushing's syndrome
Osteoporosis
Hyperglycaemia
Muscle wasting
CNS effects such euphoria and psychosis, depression