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  #1  
Old 07-05-2011
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Pancreas Exogenous vs Endogenous insulin

Exogenous peripherally injected insulin differs from endogenously secreted insulin in a number of aspects, including which of the following?


(A) achieves a higher concentration in the periphery than in the liver, contrary to endogenous insulin
(B) contains C-peptide, which is missing from secreted endogenous insulin
(C) is able to bypass insulin resistance observed with endogenous insulin
(D) is always extracted from animal sources and, therefore, is less effective due to sequence differences and anti-insulin antibodies
(E) is in the form of proinsulin, whereas endogenous insulin has had C-peptide removed
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Old 07-06-2011
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mm good question i could go for A but im not sure
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Old 07-06-2011
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(A) achieves a higher concentration in the periphery than in the liver, contrary to endogenous insulin
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Old 07-06-2011
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the answer is A
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Old 07-06-2011
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i pick A... through the process of elimination(POE)
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Old 07-06-2011
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the ans is u !
we could also discuss the factious hypoglyceamia n c- peptide levels
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Old 07-07-2011
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Can anybody put some explanation , and ( if possible) a source to read about this topic (physiology of endogenous and exogenous insulin) ?
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Old 07-07-2011
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Insulin is normally secreted by the endocrine pancreas into the portal venous drainage. Thus, it passes through the liver before being seen by the periphery. A certain fraction of insulin is extracted by the liver; so that the concentration of insulin seen by the liver is normally higher than that seen by the periphery. This discrepancy between exogenous and endogenous insulin might contribute to the problems experienced by diabetics such as hypertension and cardiovascular disease.
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