Adrenal Cortex Flashcards
Glucocortiocoids
increase availability of glucose
Cortisol: most important product
Physiological effects occur at low levels
Pharmacological effects occurs at high levels
Cushing Disease
when a physiological effect results in high levels of cortisol
Glucocorticoids Physiological effects
opposite of insulin
promote glucose availability
maintain integrety of vasucylar system
reduced GC = vasucalr permeability increases = BP falls
increase RBC counts
Stress response
GC= increased cortisol (blood glucose)
Adrenal Meducal = increased secretion of epinephrine (increased BP)
regulation of GC
neg. feedback system
secretion: 2 activations
1) Bassal stimulation to maintain a basal level that follows circadian rhythm
2) stress: increased cortisol at times of stress
Aldosterone
renal physiological effects
promote sodium and potassium hemostasis
maintains BV/BP
promtes sodium reabsorption in exchange for potassium secretion
Aldosterone regulation
via RAAS
Cushing Syndrome
excessive circulatory glucocorticoids
cause: hyper secretion of ACTH by
(1) pituitary adenomas
(2) adrenal adenomas
Cushing Syndrome treatment
partial or full surgical removal of diseased adrenal glad
replacement with glucocorticoids/ mineralocorticoids as needed
Mitotane: anticancer drug that destroys adrenal cortex tissue
drugs adjucts to surgery and radiation
Adenoma
tumor that is not cancer
Osilodrostat for cushings
when surgery is not appropriate/ successful
po/ inhibits final step cortisol synthesis in adrenal gland
adverse effect: prolong QT
- hypokalemia, hypermagnesemia
Primary Hyperaldosteronism
effect of increased renal reabsorption of sodium and water
= incrased BV/BP
Result: Hyptertension hyper kalemia, heart failure
Cause: adrenal adenoma or bilateral adreal hyperplasia
Treatment for Primary Hyperaldosternosim
adrenal adenoma = surgery
bilateral adrenal hyperplasia = aldosterone antagonist
Adrenocortical Hormone Insufficiency
Cause: malfunction along hormonal pathway, including destruction of adrenal gland
treatment lifelong replacement therapy
glucocorticoids/ mineralocorticoids or both
Glucocorticoid drugs
what should they do
Hydrocortisone, prednisone, dexamethasone
mimic circadian rhythm of glucocorticoids
mineral corticoids can be administered 1x/day
primary Adrenocortical Hormone Insufficiency Diseases
Addisons disease
autoimmune destruction of adrenal glands
adrenal atrophy
= reduced glucocorticoids/mineralocorticoids
primary adrenocortical insufficient treatment
replacement therapy with hydrocortisones
(has both glucocorticoids and mineralocorticoids)
administration: IM or IV
secondary and tertiary adrenocortical insufficiency
secondary: decreased secretion of ACTH
tertiary: decreased secretion of CRH
adverse effects: glucocorticoids diminished/ no effect on mineral corticoids
treatment: replacement therapy with Hydrocortisone
acute adrenal insufficiency (Adrenal Crisis)
Cause: pituitary/ adrenal failure/ failure to provide replacement patients adequate dose of glucocorticoids
Symptoms:
hypotension, dehydration, vomiting, diarrhea/ can progress to shock/death
treatment of acute adrenal insufficiency (adrenal crisis)
Step1: rapid replacement of fluids, salt, and glucocorticoids
Step 2: inject 100 mg hydrocortisone (IV bolus), followed by IV infusion of normal saline with dextrose/ additional hydrocortisone given at a rate of 50 mg every 8 hours
Gongenital Adrenal Hyperplasia
Cause: inborn deficiency of enzymes needed for glucocorticoid synthesis (doesnt effect mineralocorticoids)
note: to attempt to compensate, pituitary releases large amounts of ACTH
Treatment of congenital adrenal hyperplasia
1) ensure adequate levels of glucocorticoids
2) prevent excess production of ACTH
- Hydrocortisone= (1) supplies glucocorticoids which then (2) suppresses ACTH production
Hydrocortisone
synthetic steroid identical to cortisol
PO: chronic replacement therapy
Parenteral: acute and to supplement oral doses at times of stress
nonendocrine disorders: allergic reactions to cancer
adverse effects:
low doses: no adverse effects
large doses = highly toxic
Fludrocortisone
treatment for hypoaldosteronism
adverse effects
doses too large = magnified effect of mineralocorticoids
result: increased BV/BP, hypokalemia
preparations
available in 0.1mg tablets
normal dose: 1 tablet/ day
