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Discussion Starter · #1 ·
An obese individual is brought to the emergency room by a concerned friend. The patient has been on a self-imposed "starvation diet" for four months, and has lost 60 pounds while consuming only water and vitamin pills. If extensive blood studies were performed, which of the following would be expected to be elevated?

A. Acetoacetic acid
B. Alanine
C. Bicarbonate
D. Chylomicrons
E. Glucose
 

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emm kind a confused b/w alanine and acetoacetic acid.... i think Alanine bkz he is taking vit pills... B6 pyridoxine so this reaction will eventually make alpha ketogluarate from alanine using alanine transferase (SGPT) and ast (SGOT) and tca cycle will continue

B- alanine
 

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emm kind a confused b/w alanine and acetoacetic acid.... i think Alanine bkz he is taking vit pills... B6 pyridoxine so this reaction will eventually make alpha ketogluarate from alanine using alanine transferase (SGPT) and ast (SGOT) and tca cycle will continue

B- alanine
i tot acetoacetic acid too. because when ure starving then yr FAs are mobilized for use instead. also, how do u know the patient is taking B6 vitamin. maybe she's taking only vit c?:(
 

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Discussion Starter · #5 ·
A is correct

Sorry guys you got it wrong cuz serum alanine drops dramatically in starvation, due to its conversion to glucose.In starvation state glucose cannot be synthesized from lipids, and is instead made from amino acids such as alanine in
the process of gluconeogenesis.the body's energy requirements are supplied by both glucose and lipid-derived ketone bodies, including acetoacetic acid and beta-hydroxybutyric acid.So ,A is the right answer
 

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Sorry guys you got it wrong cuz serum alanine drops dramatically in starvation, due to its conversion to glucose.In starvation state glucose cannot be synthesized from lipids, and is instead made from amino acids such as alanine in
the process of gluconeogenesis.the body's energy requirements are supplied by both glucose and lipid-derived ketone bodies, including acetoacetic acid and beta-hydroxybutyric acid.So ,A is the right answer
dear dr.sam...

i answered acetoacetic acid! :p
 

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o lolz!!!!:))
i didnt think carefully that wats elevated is asked... happens often!!:D
 

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the actual answer is alanine of course - yes you are correct that alanine is actively converted to glucose by the liver but in fact the levels go up because muscles catabolize protein to make glucose and then since there is no urea cycle in the muscle the only way to eliminate the leftover amino groups is by synthesizing them into alanine so the relative concentration of alanine in the serum goes up quite a bit as a result since this is the only method in muscle to eliminate nitrogen groups (some other tissue can do it differently). This would be much higher in early starvation but higher in late starvation as well.

This is also a trick question - you can't measure acetoacetate in serum - the only ketone you measure by standard tests is b-hydroxybuterate that is why that is an incorrect answer
 

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A) Acetoacetic acid

An obese individual is brought to the emergency room by a concerned friend. The patient has been on a self-imposed "starvation diet" for four months, and has lost 60 pounds while consuming only water and vitamin pills. If extensive blood studies were performed, which of the following would be expected to be elevated?

A. Acetoacetic acid
B. Alanine
C. Bicarbonate
D. Chylomicrons
E. Glucose
The correct answer is A. Long-term starvation induces many biochemical changes. Much of the body's energy requirements are normally supplied by serum glucose, but in starvation are supplied by both glucose and lipid-derived ketone bodies, including acetoacetic acid and beta-hydroxybutyric acid. Glucose cannot be synthesized from lipids, and is instead made from amino acids such as alanine in the process of gluconeogenesis.

Serum alanine (choice B) drops dramatically in starvation, due to its conversion to glucose.

Bicarbonate (choice C) levels drop as the bicarbonate buffers the hydrogen ions produced by the ketone bodies.

Chylomicrons (choice D) are the lipid form seen after absorption of dietary fat, and would drop because the person is not feeding.

Glucose (choice E) is maintained in the blood at a much lower than normal level during starvation.
 

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My understanding is that excess amino groups can be transported in the blood to the portal system as Glutamate (by adding NH3 to alpha-ketoglutarate) or glutamine (by adding another NH3 to glutamate) - I don't think alanine alone has to be used. However, I was still wondering about Alanine though. Isn't skeletal muscle derived alanine transported to the liver for gluconeogenesis because skeletal muscle can't perform this? And after 4 months wouldn't there be a fair chance she's gotten to the point of protein metabolism? I guess she must have been rather obese and still had sufficient fat stores.
 
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