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q-3

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8 Posts

me007
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Topics: 72
Posts: 803

01/17/07 - 11:45 PM

women with Cushing has hypeglycemia
Which of the following enzymes is most likely causing the hyperglycemia?
a. aspartate aminotransferase
b. capillary lipoprotein lipase
c. phosphoenolpyruvate carboxykinase
d.pyruvate carboxylase
e. pyruvate dehydrogenase

Ancylostoma
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Topics: 42
Posts: 642

01/18/07 - 12:04 AM

D. Gluconeogenesis rate limiting enzyme

Luckyall
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01/18/07 - 01:03 PM

me007
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Posts: 803

01/18/07 - 01:05 PM

try again

Luckyall
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01/18/07 - 01:20 PM

pepck, b c is te key limiting enzyme and is regulated by Cortisol

MRMAVERICK
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Posts: 721

01/18/07 - 01:58 PM

PEPCK is induced by cortisol-

Ancylostoma
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Topics: 42
Posts: 642

01/18/07 - 02:01 PM

I'm glad you put this up there, I'll make sure I memorise it

me007
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Topics: 72
Posts: 803

01/18/07 - 02:20 PM

ok, pyruvate carboxilase is rate limiting in gluconeogenesis, the reaction it catalyzes is pyruvate ->OAA
And hyperglycemia and diabetes mellitus in Cushing's is due to gluconeogenesis
But pyruvate carboxylase is not affected by glucocorticoids! sad

Choice C - PEP carboxykinase is correct.
It is gluconeogenic enzime affected by glucocorticoids.

B - no. Hormone- sensitive lipase, not lipoprotein lipase is increased by glucocorticoids

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