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Hypothalamus
Anterior Pituitary Category
Adrenals
Cortisol & Steroids
Actions & Feedback
100
What are some stimuli that cause release of the hypothalamic hormone onto the AP? 
Circadian rhythm, stress, low glucose
100
What hormone of the HPA axis negatively feeds back on the AP and Hypothalamus? 
Cortisol
100
Cortex has 3 layers, which are ______, _______, _______ from outside to inside? 
ZG 

ZF 

ZR

100
All steroids are produced from this 27 C precursor? 
Cholesterol 
100
Cortisol is considered ___________ (characterized by gluconeogenesis, lipolysis, proteolysis) and Diabetogenic 
Catabolic 
200
What hormone is released from the hypothalamus onto the AP?
CRH 
200
What hormone is released in response to CRH (from the hypothalamus) from the AP? 
ACTH
200
In general (with a little blurring of the lines), the 3 regions in the adrenal cortex produce these 3 types of steroids respectively.... 
1. ZG--> Mineralocorticoids 

2. ZF--> Glucocorticoids 

3. ZR--> Adrenal Androgens 

200
Name at least 5 of the 7 types of compounds that can synthesized from cholesterol? 
Glucocorticoids (Cortisol) 

Mineralocorticoids (Aldosterone) 

Androgens (Testosterone, Estrogen) 

Progesterone 

1, 25 dihydroxide CCF 

Thyroxine 

200
One reason we were concerned about infection in our patient is that cortisol has this effect on the immune system?
Suppress 
300
From what nucleus in the hypothalamus is CRH released? 
Paraventricular Nucleus
300

CRH from the hypothalamus exerts its effects on this cell type in the anterior pituitary? 

Corticotrophs
300
What condition are we concerned about after surgical resection of a cortisol-producing tumor that the patient has become sensitized to? 
Addison's Disease 
300
Cortisol is synthesized ____________ 


Cortisol most often diffuses through the cell membrane to reach the _________ where it has most of its actions. 

On demand 


Nucleus, DNA, genes, etc same idea with things that have to do with increased transcription 

300
Cortisol is considered to be the long term pathway associated with prolonged stress. The short pathway when stressors occur takes what route? 
Hypothalamus with sympathetic fibers to the adrenal medulla, where epinephrine and NE are released to directly cause the fight or flight response. 
400
For hormones of the Posterior Pituitary, hormones are (synthesized in/released by) the hypothalamus & go to the Posterior Pituitary where they have their action. Think of ADH for example.  


For hormones of the Anterior Pituitary, hormones are (synthesized in/ released by) the hypothalamus & act on the Anterior Pituitary. 

PP: Synthesized in 


AP: Released by 

400
What happens to the level of ACTH in a normal patient if they are given a dexamethasone suppression test? 


The high dose steroid would decrease the level of ACTH. 

400
The adrenals have to pick up this compound from the blood (in addition to ACTH) to be able to synthesize steroids. 
Cholesterol from LDL 
400

ACTH directly stimulates the first step in steroid synthesis from cholesterol, which is catalyzed by what enzyme? 

Cholesterol Desmolase
400

The presence of an appropriately functioning feedback mechanism allows for distinguishing between a cortisol producing tumor and an ACTH producing tumor. How? 

Dexamethasone test 


If you give Dexamethasone (like cortisol) and there is an ACTH-producing tumor, ACTH will remain high and it will not work to feed back on the AP. 


If you give Dexamethasone (like cortisol) and there is a cortisol-producing tumor, ACTH will decrease due to the proper functioning of negative feedback. 

500

From what nucleus do the Sympathetic NS fibers that act on the adrenal medulla originate? 

Posterior Nuclei 
500
What is one short vs. long term effect of ACTH on target cells?

Short Term effects of ACTH are to transfer stored cholesterol to the mitochondria, stimulate cholesterol binding to CYP450, and stimulate Cholesterol Desmolase  


Long term effects of ACTH are stimulation of transcription of genes for CYP450, and upregulation of ACTH receptors



500
Detecting 17 ketosteroids refers to which two compounds? 
DHEA and Androstenedione 


They are weak adrenal androgens with ketone group rather than the OH found in testosterone/ estradiol. 

500
What one C # (what position) has a OH group in cortisol that aldosterone does not have?  
17
500
If there is a mutation in 21 hydroxylase or 11 hydroxylase, what will be the predominant steroid hormone that produced from cholesterol? 
Androgens