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pro·in·su·lin (')prō-'in(t)-s(ə-)lən n a single-chain pancreatic polypeptide precursor of insulin that gives rise to the double chain of insulin by loss of the middle part of the molecule
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n.
a substance produced in the pancreas from which the hormone insulin is derived.
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pro·in·su·lin (pro-inґsə-lin) a precursor of insulin, with a molecular weight of 8,000 to 10,000; it has minimal hormonal activity and is converted to insulin by removal of the connecting C peptide, leaving the two (A and B)-chain, active insulin molecule.Medical dictionary. 2011.