Adrenal Flashcards
3 cell layers of the adrenal cortex from out to in and what they produce
- glomerulosa - aldosterone
- fasiculata - cortisol
- reticularis - DHEA
what does hypo release in response to stress
CRH and ADH
what does CRH do?
stim ACTH
what does ACTH do
- stim. cortisol release
2. adrenal hyperplasia and hypertrophy
what does ADH do in the ant. pit?
works to increase ACTH upregulation
what does cortisol feed back onto?
-ve to hypo, pit
where are glucocorticoid receptors located
hypo and ant. pit
where are mineralocorticoid receptors found
in brain- act as glucocorticoid receptors
what happens with long-term glucocoritcoid therapy
adrenal hypertrophy
4 metabolic effects of glucocorticoids
- up hepatic glucogenisis - conversion of AA to glucose
- up protein catabolism - more AA in blood
- down glucose tissue uptake - more glucose for brain
- up lipolysis - alternative E source
permissive effect of GCs
increase catecholamines - more CV response in stress
immune effects of CG
immunosuppresive via less imflammation
behavioral effects of CG
mood and memory
what are steroids derived from
pregnane
what happens when missing cholesterol desmolase
no hormones- lethal
what happens when don’t have 21B or 11B hydroxylase
don’t get conversion from pregane to cortisol - CAH
what is cortisol to corticosterone ratio in humans
7:1
what is step to make cortisol
- ACTH bind and SF-1 does enzyme synthesis
- cholesterol to pregnenolone in mitochond.
- preg to ER
- Pre to deoxycortisol in ER
- deoxycortisol to mitochond.
- deoxycortisol to cortisol in mito
half life of cortisol
60-90 mins
peak and nadir of cortisol (time)
peak - 7am
nadir - 7pm-12am
what area is responsible for HPA rhythms
suprachiasmatic nucleus
how does cortisol move in blood
5% free
95% bound to CBG and albumin
where is CBG created
in liver
what is 11B-HSD
enzyme that coverts cortisol to cortisone
2 types of HSD and fucntion
HSD1 - back and forth
HSD2 - cortisol to cortisone only
what is function of HSD2
protects fetus and kidneys from cortisol
what does skin do via HSD1
turns cortisone cream to cortisol
how is cortisol excreted
turned into tetrahydrocortisone glocuurinide and out liver and kidney
how are androgent regulated in adrenal
by ACTH
how is more androgen made in adrenals
99.9% sulphoconjugated
what happens to androstendione
converted to T and E in circulation
what is aldosterone pathway
- low ECF volume and renal artery pressure signals
- Renin secreted
- renin converts angiotensinogen to angiot 1
- ACE converts 1 to 2
- angio 2 stims adrenal to produce aldosterone
- aldosterone increased Na and H2O absorbtion
what happens if have no 17a hydroxylase
only produce glucocorticoids
what is syndrome name, cause and Sx of excess aldosterone
Syndrome: Conn’s
Cause: hypersecreting tumor of glomurelosa
Sx: hypernatremia and hypertension
what is syndrome name, cause and Sx of excess cortisol
Syndrome: cushings
Cause: hypersecreting tumor of fasciulata
Sx: excess glucose, protein shortage, fat dist weird, poor wound healing
what is syndrome name, cause and Sx of excess androgen
Syndrome: andrenogenital syndrome
Cause: lack of enzyme to convert to cortisol
Sx: masc. in women and prepuberty in boys
what is syndrome name, cause and Sx of deficit in aldosterone and cortisol
Syndrome: Addisons
Cause: destruction or atrophy of adrenal cortex
Sx: hyponatremia and hypotension
what is syndrome name, cause and Sx of cortisol deficit
Syndrome: secondary adrenocortical insufficiency
Cause: HPA failure, insuff CRH/ACTH
Sx: poor stress response, hypoglycemia, metabolic deficits
