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.
from proinsulin only: not for peptide fragments from other proteins (
Other names Proinsulin C-Peptide; Proinsulin C Peptide; C Peptide, Proinsulin; C Peptide; Connecting Peptide; C-Peptide, Proinsulin