Adrenocortical steroids Flashcards
What does the hypothalamus release to stimulate the adrenal cortex? what does it act on?
corticotropin releasing hormone CRH
Pituitary
What does the pituitary release to stimulate the adrenal cortex?
adrenocorticotropin ACTH
What is the major precursor to the creation of aldosterone, cortisol, and androgens?
cholesterol and pregnenolone
What zone is aldosterone released from?
zona glomerulosa
What zone is cortisol and androgens from?
zona fasciculata and reticularis
What also increases activity of zone glomerulosa besides ACTH?
K and angiotensin II
What does increased ACTH levels result in?
adrenal hyperplasia and decreased ACTH levels result in hypoplasia
What are the 5 main effects of glucocorticoids?
- increased protein breakdown
- increase lipolysis and cause fat redistribution
- increase gluconeogenesis and glycogen synthesis
4 decrease glucose utilization - inhibit immune system and inflammatory response
T-f–do cytokines from the immune system inhibit the hypothalamus and pituitary and their release of CRH and ACTH?
False- they increase release
The kidney is the main effector organ of mineral corticoids…what are the 3 main effects?
Increase Na reabsorption
Increase K excretion
Increse H excretion
T-F mineral corticoids are usefule in treating adrenal insuficiency and immune/inflammatory disorders?
false- only glucocoticoids do both, mineral corticoids only for adrenal insuficiency
What is the glucocorticoid activity, mineral corticoid activity and method of administration for the following steroids-
- cortisol
- prednisolone
- Fludrocortisone
- Dexamethasone
- 1, 1, oral, injection, topical
- 5, .3, oral,injection
- 10, 250, oral
- 30, 0, oral, injectable, topical
What are 4 common uses of glucocorticoids for non-adrenal disorders?
- speed up lung maturation prior to birth
- suppressing the immune system prior to organ transplant
- treatment of childhood acute lymphoblastic leukemia (w/methotrexate)
- suppressing immune system for a variety of inflammatory and immune disorders
T-F-side effects are few when used systemically for under 2 weeks?
True
When do we see side effects with glucocorticoids?
Used at high doses (greater 100mg) for over 2 weeks
Review the list of side effects of glucocorticoids–
- hyperglycemia and glycosuria
- increased protein breakdown
- increased infection risk
- myopathy
- osteoporosis
- behavior change
- cataracts
- ulcers
- sodium and fluid retention, loss of potassium
- growth retardation in children
- supression of HPA acis
What commonly results from withdrawal of glucocortcoids?
flare up of underlying disease and adrenal insufficiency
T-f–when administering glucocorticoids we should use the smallest possible dose?
True and check periodically
Why should we use alternate day administration of glucocorticoids?
Alleviates suppression of the HPA axis
T-F with glucocorticoids we should administer together with newer immune suppressants?
True
How should we modify our diet when using glucocorticoids?
high protein, high K and low Na
What is the most widely used mineral corticoids?
fludrocortisone
Are both glucocorticoids and mineral corticoids useful in acute adrenal insufficiency and chronic adrenal insufficiency?
yes
In congenital adrenal hyperplasia 1, what enzyme is taken out?
21 beta hydroxylase– see increases in pregnenolone, progesterone, and androgens.
In congenital adrenal hyperplasia 2, what enzyme is taken out?
11 beta hydroxylase– see increases in 11- deoxycorticosterone and 11 desoxycortisol and pregnenolone, progesterone, and androgens.
How to treat CAH 1?
- Mineralocorticoids + salt as replacement
therapy - Glucocorticoids
- Antiandrogens
How to treat CAH 2
- Mineralocorticoid antagonists and salt
restriction - Glucocorticoids
- Antiandrogens
Is eplerenone or spironolactone an androgen antagonist?
spironolactone
Cushings syndrome that increases cortisol production is caused by what 2 things?
- primary adrenal defect
- increased ACTH (pituitary or other tissue)
[hypertension, hyperglycemia, fat redistribution and muscle wasting]
What are the 2 main treatments for cushings?
Surgery or irradiation
drugs that block adrenocortical steroid
When does dexamethasone suppress cortisol?
If cushings is due to increase ACTH secretion by pituitary (cushing’s disease)
What does it mean if dexamethasone does not suppress cortisol?
- primary adrenocortical hyper function
2. ACTH secretion by tumor or other tissues
