Corticosteroids

Question 1

layers of adrenal gland

Answer 1

cortex -
glomerulosa(aldosterone) ;
fasiculata(cortisol),
reticularis(androgens)

medulla -

Question 2

adrenal axis

Answer 2

hypothalamus stimulated by stress / diurnal cycle
releases CRH

pituitary releases ACTH
** {mainly stimulates fasiculata and reticularis} **
increased uptake of cholesterol into cells and mitochondria … conversion to pregnelone

adrenal corticosteroids (-) feedback to hypothalamus

lack of ACTH causes degeneration of FR zones

Question 3

what enzyme converts cholesterol to pregnenolone

Answer 3

desmolase

Question 4

how many carbons in
glucocorticoids (cortisol)
mineralocorticoids (aldosterone)
androgens

Answer 4

21C

19C - androgens

Question 5

corticosteroid biosynthesis

Answer 5

cholesterol –> desmolase
pregnenolone

Glomerulosa:
progesterone --> 21-monooxygenase
11-DOCS --> 11-beta-monooxygenase
corticosterone -->aldosterone synthase
aldosterone

Fasiculata:
pregnenolone –> 17alpha-monooxygenase
17alpha-something –>21-monooxygenase
11-Deoxycortisol –>11-beta-monooxygenase

Reticulata:
pregnenolone –> 17alpha-monooxygenase
17alpha-something
dehydroepiandrosterone & androstenedione
…estrone (little)
…testosterone –>5-alpha-reductase…DHT
…testosterone –> aromatase …estradiol

Question 6

can adrenal corticosteroids be stored in the adrenal gland

Answer 6

no

reservoir is the blood

Question 7

11-beta hydroxysteroid dehydrogenase

11-B-HSD

Answer 7

it deactivates glucocorticoids (cortisol) in mineralocorticoid tissue - so tissue is responsive to aldosterone

Question 8

permissive effect

Answer 8

catecholamines require presence of cortisol to work on vascular and bronchial smooth muscle

Question 9

use corticosteroids in preterm when

Answer 9

24-34 weeks

Question 10

corticosteroids curative?

Answer 10

no

only suppress symptoms

Question 11

ADR of corticosteroids

Answer 11

aldosterone = fluid retention
cortisol = hyperglycemia, glucosuria

immune suppression
orally - thrush
osteoporosis
cushings
muscle wasting
proximal myopathy
depression
hypertension - volume and cortisol independent

Question 12

adrenal insufficiency

Answer 12

lack of aldosterone = Na wasting
fatigue
orthostatic hypotension
hyperpigmentation

primary adrenal dysfunction then ACTH will be high
autoimmune (addisons)
adenoma
secondary due to pituitary dysfunction ACTH low

Question 13

cushings syndrome

Answer 13

hypercortesolemia
moon facies
dorsal fat pad
abdominal stria
abdominal adiposity

exogenous
endogenous -
primary adrenal dysfunction ACTH low
secondary due to high ACTH

key causes:
pituitary adenoma (cushing's  disease)
actopic ACTH
adrenal adenoma
ectopic glucocorticosteroids