C peptide

(redirected from connecting peptide)

C peptide

a biologically inactive residue of insulin formation in the beta cells of the pancreas. When proinsulin is converted to insulin, an equal amount of C peptide, a chain of amino acids, is also secreted into the bloodstream. Beta cell secretory function can be determined by measuring the C peptide in a blood sample.

C peptide

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 increased C-peptide (= 0.2 nmol/L) as well as increased insulin (= 42 pmol/L) is characteristic of insulinoma. C peptide quantification is used to detect fictitious insulin injection and diagnose insulin-secreting tumours in diabetics, where > 7 ng/ml of C peptide after induced hypoglycemia supports the diagnosis of insulinoma.
References in periodicals archive ?
A novel secretory product of the rat pancreatic [beta] cell produced by truncation of proinsulin connecting peptide in secretory granules.
The insertion in the HA protein sequence from the Fraser Valley isolates does not conform to the consensus motif (R-X-R/K-R*-G-L-F) for an HA1 HA2 connecting peptide in HPAI viruses because a threonine is at the -2 position.