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PubMed · 194989

C-peptide suppression test for insulinoma.

F J Service·D L Horwitz·A H Rubenstein·H Kuzuya·M E Mako·C Reynolds·G D Molnar
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Abstract

During hypoglycemia induced by an infusion of porcine insulin, impaired suppression of endogenous insulin secretion as measured by C-peptide was demonstrated in 11 of 12 patients with insulinoma. During hypoglycemia (plasma glucose less than or equal to 40 mg/dl) the mean C-peptide immunoreactivity (CPR) of normal subjects was less than or equal to 1.2 ng/ml, whereas 11 of 12 insulinoma patients had a mean CPR of larger than or equal to 1.9 ng/ml. One patient showed normal CPR suppression by these criteria but may have shown impaired CPR suppression for glucose less than or equal to 30 mg/dl. Impaired CPR suppression during insulin-induced hypoglycemia may prove to be a useful test for insulinoma.

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Adenoma, Islet CellAdultAgedBlood GlucoseC-PeptideFeedbackFemaleHumansInsulinInsulin SecretionMaleMiddle AgedPancreatic NeoplasmsPeptidesProinsulinTime FactorsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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F J Service, D L Horwitz, A H Rubenstein, H Kuzuya, M E Mako, C Reynolds, G D Molnar. 1977. C-peptide suppression test for insulinoma.. https://pubmed.ncbi.nlm.nih.gov/194989/

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