25.5 Phys: Adrenocortical function and dysfunction Flashcards
Where are sex hormones, glucocorticoids and aldosterone made within the adrenal cortex?
SH: zona reticularis
GC: zona fasiculata
AL: zona glomerulosa
What areas is ACTH tropic to?
ZF, ZR
What is special about mineralcorticoids in terms of location made compared to the other hormones?
They are only made in the glomerulosa (others have overlap)
What are mineralcorticoids stimulated by?
RAAS and plasma K+
What 2 precursors can we get androgens from?
Progesterone and DHEA
How do cells produce different steroids?
They contain different enzymes
What is POMC? What can it produce (inside and outside the pituitary)
Pro-opiomelanocortin
Inside: (ACTH and B-endorphin)
Outside: a-MSH
When does cortisol peak? What kind of rhythm is this?
Peaks in the morning (diurnal rhythm), low at night
What is cortisol permissive for?
Glucagon and catecholamine action
What does cortisol do to calcium balance?
Causes negative calcium balance (decreased absorption, increased excretion)
What does long term cortisol (therapeutically) do to the body? What does this mean you have to do with the dose?
Inhibits ACTH and atrohpy of cortisol-secreting cells (taper the doses gradually)
What can primary and secondary hyperaldosteronism be due to?
What do they cause?
1: Conn’s syndrome
2: RAS
Increased Na, decreased K+, hypertension
What are primary and secondary causes of excess cortisol aka Cushing’s syndrome?
1: adrenal cortex tumour
2: Cushing’s disease, pituitary tumour
What do we treat excess androgen/oestrogen with?
Glucorticoids
What is primary adrenal insufficiency due to?
Addison’s disease
