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Vustipalli. Ravi kanth Reddy

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Adrenocorticotropic hormone (ACTH)
CONTENTS
Adreno cortcotropic harmone (ACTH) or CORTICOTROPIN
ACTH is secreted from the anterior pituitary in response to corticotropin-releasing hormone (CRH) from the hypothalamus. CRH is secreted in response to many types of stress( Corticotropin-releasing hormone itself is inhibited by glucocorticoids, making it part of a classical negative feedback loop.)
ACTH acts on adrenal cortex to release cortisol.
Cortisol is needed for life, so its levels in the blood are closely controlled. When cortisol levels rise, ACTH levels normally fall. When cortisol levels fall, ACTH levels normally rise.
Within the pituitary gland, ACTH is produced in a process that also generates several other hormones. A large precursor protein named proopiomelanocortin (POMC, "Big Mama") is synthesized and proteolytically chopped into several fragments as depicted below.
MOA: on adrenal cortex.
Both ACTH and cortisol levels change throughout the day. ACTH is normally highest in the early morning (between 6 - 8 a.m.) and lowest in the evening (between 6 -11 p.m.).
Normal values: 9 - 52 pg/mL
Low levels of ACTH :
Pituitary insufficiency
Cushing's syndrome
DEXAMETHASONE FLUDROCORTISONE HYDROCORTISONE (cortisol) METYRAPONE PREDNISOLONE beclomethasone betamethasone dehydroepiandrosterone (DHEA) fluocinonide
TREATMENT:
ACTH THERAPEUTIC USE:
ACTH stimulation test :
The ACTH stimulation test (also called the  cosyntropin test,  tetracosactide test or  Synacthen test) is a medical test to assess the functioning of the adrenal glands stress response by measuring the adrenal response to adrenocorticotropic hormone
TYPES:
the low-dose short test
conventional-dose short test
The prolonged-stimulation test
Preparation 4 test :
The person must fast atleast 8 hours b4 the test .
During the test, a small amount of synthetic ACTH is injected, Approximately 20 mL of heparinized venous blood is collected at 30 and 60 minutes after the injection.
the amount of cortisol,& sometimes aldosterone, the adrenals produce in response is measured.
 glucocorticoids, Spironolactone, contraceptives, licorice,estrogen, androgen  and progesterone therapy may also affect both aldosterone and cortisol stimulation test results.
sodium must be fasted for 24 hours prior to testing. (allows aldosterone to rise as far as possible)
Cortisol stimulation
In healthy individuals, the cortisol level should double from a baseline of 20-30 ug/dl within 60 minutes.
For example, if the serum cortisol level was 25 ug/dl before the stimulation, it should reach at least 50 ug/dl.
Interpretation for primary adrenal insufficiency and Addison's disease