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Flashcards in Corticosteroids Deck (13):
1

layers of adrenal gland

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

medulla -

2

adrenal axis

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

3

what enzyme converts cholesterol to pregnenolone

desmolase

4

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

21C
19C - androgens

5

corticosteroid biosynthesis

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

6

can adrenal corticosteroids be stored in the adrenal gland

no
reservoir is the blood

7

11-beta hydroxysteroid dehydrogenase
11-B-HSD

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

8

permissive effect

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

9

use corticosteroids in preterm when

24-34 weeks

10

corticosteroids curative?

no
only suppress symptoms

11

ADR of corticosteroids

aldosterone = fluid retention
cortisol = hyperglycemia, glucosuria

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

12

adrenal insufficiency

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

13

cushings syndrome

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