C-peptide

C-pep·tide

(pep'tiīd),

The 30-amino-acid chain that connects the A and B chains of insulin in proinsulin; removed in the conversion of proinsulin to insulin.

Synonym(s): C chain

Farlex Partner Medical Dictionary © Farlex 2012

C-peptide

Connecting peptide Endocrinology A biologically inactive moiety of proinsulin produced endogenously in the pancreas, and stored in secretory granules in a 1:1 ratio with insulin; unlike factitious hypoglycemia, which is induced by insulin of exogenous origin, an ↑ in C-peptide–≥
0.2 nmol/L, as well as ↑ insulin, ≥ 42 pmol/L is characteristic of insulinoma; C-peptide quantification is used to detect fictitious insulin injection and diagnose insulin-secreting tumors in diabetics, where > 7 ng/ml of C-peptide after induced hypoglycemia supports a diagnosis of insulinoma. See Diabetes, Insulin.

McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.