C-Peptide

**Definition:** The middle segment of proinsulin that is between the N-terminal B-chain and the C-terminal A-chain. It is a pancreatic peptide of about 31 residues, depending on the species. Upon proteolytic cleavage of proinsulin, equimolar INSULIN and C-peptide are released. C-peptide immunoassay has been used to assess pancreatic beta cell function in diabetic patients with circulating insulin antibodies or exogenous insulin. Half-life of C-peptide is 30 min, almost 8 times that of insulin.

**Tree numbers:** - D06.472.699.587.200.500.250 - D12.644.548.586.200.500.250

**Synonyms:** - C-Peptide, Proinsulin - Connecting Peptide - Proinsulin C-Peptide