Term
What are the two regions of the adrenal gland? |
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Definition
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Term
What are the three layers of the adrenal cortex (superficial to deep)? |
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Definition
Zona glomerulosa mineralcorticoids: primarily aldosterone Zona fasciculata glucocorticoids: primarily cortisol Zona reticularis androgens: primarily DHEA |
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Term
What is the most secreted hormone from the adrenal cortex, its subgroup, and its zone of the cortex. |
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Definition
Cortisol Glucocorticoids Zona Fasciculata |
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Term
What are the three components of the HPA axis? |
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Definition
Hypothalamus Anterior Pituitary Adrenal Cortex |
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Term
What are the effects of ACTH on the adrenal cortex? |
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Definition
Adrenocorticotrophic Hormone -Promotes growth and function of all 3 cortical zones. -Effects secretion of glucocorticoids (much more than mineralcorticoid secretion) FYI: Adreno (Adrenal Gland)--Cortico (Cortex)--Tropic (Growth) |
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Term
In the synthesis of steroid hormones from cholesterol, what is the first and rate limiting step? |
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Definition
The conversion of cholesterol to pregnanolone. |
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Term
Glucocorticoids 1. anabolic or catabolic? 2. Where are they produced and secreted? 3. What are their main targets? 4. What are they derived from? |
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Definition
1. Catabolic 2. Zona fasiculata of the adrenal cortex 3. Liver, skeletal muscle, fat 4. Derived from pregnenolone, which is from cholesterol. |
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Term
What are the major effects of cortisol? |
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Definition
Catabolism Energy metabolism sympathoadenal effects Anti-inflammatory and immunosupressive |
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Term
What is the primary glucocorticoid in humans? Is it bound in circulation? |
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Definition
Cortisol Yes, it is bound to CBG (Transcortin) -Blunts fluctuations in cortisol blood levels High on the half-life continuum |
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Term
Describe glucocorticoid receptor activation pathway? |
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Definition
1. The bound hormone comes to the membrane dissociates from its carrier and enters the cell. 2. Hormone binds to its intracellular receptor, activates it and causes dissociation of heat shock proteins. 3. Dimerization occurs and it binds to the hormone response element on the DNA target (glucocorticoid response element) |
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Term
What types of stress stimulate cortisol secretion. |
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Definition
Physical stress hypoglycemia trauma exercise Mental Stress acute anxiety and chronic anxiety |
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Term
Compare and contrast glucagon and cortisol |
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Definition
Compare Both are catabolic both focus on increasing blood glucose Breaks down proteins, this generates urea Contrast Cortisol, unlike glucagon, promotes the synthesis of glycogen. Cortisol is from the fasiculata layer of the adrenal cortex while glucagon is from alpha cells of the islets of langerhans in the pancreas. |
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Term
What is cortisol's effect on inflammation and immune response? How can this be beneficial and also harmful? |
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Definition
It supresses both the immune and inflammatory response. It can beneficial at stopping transplant rejection, stopping rashes, or for sore joints. Its bad because it supresses your immune system's ability to fend off infections. |
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Term
Mineralcorticoids 1. What are their protein carriers? 2. Where are they produced and secreted? 3. What are their main targets? -what's their function |
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Definition
Example: Aldosterone 1. Albumin, CBP carrier 2. Zona glomerulosa of the adrenal cortex 3. Kidneys -Sodium Retention -Water Retention -Potassium Excretion |
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Term
Summarize control of aldosterone |
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Definition
1. juxtaglomerular cells sense decrease in blood pressure or volume. 2. Rennin is secreted 3. Angiotensinogen is converted to angiotensin I 4. Angiotensin I is converted to angiotensin II, which targets Zona glomerulosa cells to produce aldosterone. |
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Term
Since cortisol has limited mineralcorticoid activity similar to that of aldosterone and considering cortisol is produced in much larger quantities... Why doesn't cortisol take over for aldosterone? |
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Definition
The Enzyme Protective Effect! In aldosterone responsive cells, cortisol becomes inactivated to cortisone. |
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Term
What conditions occur from an adrenal cortex pathology? |
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Definition
Addison's Disease (Destruction of Adrenal Cortex, lack of gluco- and mineral- corticoids) Cushing's Disease (excess cortisol) These can be cause by primary causes (autoimmune destruction or infection) or by secondary causes (Hypothalamic/pituitary failure) |
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Term
What are some signs and symptoms of Addison's Disease? |
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Definition
Basically no mineral- or gluco- corticoids Can see pigmentation of Mucosa Low Aldosterone causes Hypotension (not retaining water) Hyponatremia (not retaining sodium) Hyperkalemia (not excreting potassium) Low Cortisol Causes hypoglycemia weight loss apetite loss |
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Term
What are some causes of Cushing's Syndrome |
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Definition
Cushing's aka hypercortisolism can happen from: Secondary: Tumor on the anterior pituitary, secretes excess ACTH (Adrenocorticotropic Hormone) Or more commonly, exposure to exogenous sources of cortisol |
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