L5 - mineral cort and androgens Flashcards
what are mineral cort
teroid hormones that regulate salt and water balances
the main mineralcorticois
aldosterone
synthesis of aldosterone
progesterone>
11-deooxycorticosterone > corticosterone>
18 hydroxycorticosterone> aldosterone
how is aldosterone or minercal cort transported in the blood
- free in plasma
- can bind to albumin or trasncortin
- doesnt have specific binding protein
how to regulate Aldosterone secretion
- only high levels of ACTh increase it
- increase in plsma potassium to increase
- decrease plasma Na to increase
- renin - angiotensin system
mechanism for using aldosterone to restore ECF AND BP
ECF falls
- BP falls
- cells in kidney detect the drop in press ure
- Juxtaglomerular cells release renin
- cause angiotensin to convert to angiotensin I
- then again converted to angiotensin II then bind to receptor in the kidney cortex
- the angiotensin II increases aldosterone secretion
- increases Na + and increases BP
receptors that interact with aldosterone
- glucort receptor but has affinity of cortisol> aldosterone
- mineral cort receptor and has same affinity for cortisol and aldosterone but prefers cortisol over aldosterone
symptoms associated with mineralcort excess
- severe HP (BP too high)
- has low levels of K cos aldosterone decrease K levels and increase Na level
- low renin, low aldosterone
effects of mineralcort
- increase Na reabsorption on DCT, collecting duct, sweat glands
- decrease K reabsorption
- increases H loss - leads to metabl alkosis
- increases water reabsorption
whats the primary and secondary conditon assoicated with hyperaldosterism
primary - autonomous production of aldosterone
secondary - increase aldosterone levels due to high renin levels
disease associated with primary hyperaldosterism
conn syndrome
causes for primary hyperaldosterism
hyperplasia
- adrenal adenoma in the zona glomerulsosa
- renin not affected here so normal or lowe level
symptoms for primary hyperaldosterism
hypertension
-alkalosis
hypokalaemia
treat ment for primary hyperaldosterism
surgery
cause for secondary hyperaldosterism
renal artery probelm
- duiertic therapy
- renin levels high so increase aldosterone levels
disease associated with secondary hyperaldosterism
addisons disease
where are adrenal androgen synthesised
in small amounts in zona reticularis like DHEA and androstenedione
what is CAH
congenital adrenal hyperplasia
- where the adrenal glands is enlarged during childhood or development
symptoms of CAH
dehyration, salt loss, weakness
treatment for CAH
corticosteroids replacement
cause for CAH
mutation of 21 hydrolase in the enzyme
- decreases glucort and mineralcort production
-decreases neg feedback >
increase ACTH >
makes the adrenal glands to release DHEA then release androgens > adrenal hyperplasia
