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Updated: Jul 27, 2026
11:10
Hyperinsulinemic-euglycemic Clamps in Conscious, Unrestrained Mice
Published on: November 16, 2011
Summary
This study shows that C-peptide levels are a more stable indicator of insulin secretion than immunoreactive insulin (IRI) in normal and diabetic individuals. Insulin antibodies can impair IRI and C-peptide responses, highlighting C-peptide
Area of Science:
- Endocrinology
- Metabolic Disorders
- Diabetes Research
Background:
- Assessing pancreatic beta-cell function is crucial for understanding diabetes.
- Human C-peptide and immunoreactive insulin (IRI) are key markers of insulin secretion.
- Variations in insulin secretion can be influenced by factors like insulin antibodies.
Purpose of the Study:
- To compare the reliability of C-peptide and IRI measurements in assessing insulin secretion.
- To investigate the impact of insulin antibodies on C-peptide and IRI responses.
- To evaluate C-peptide as a diagnostic marker in different diabetes types.
Main Methods:
- Oral glucose tolerance test (OGTT) administered with 1.75 g glucose/kg ideal body weight.
- Measurement of serum glucose, C-peptide, and immunoreactive insulin (IRI) concentrations.
- Analysis of fasting and post-glucose C-peptide and IRI levels in normal and diabetic subjects.
Main Results:
- Maturity-onset diabetics exhibited higher fasting C-peptide and IRI levels than normal subjects.
- In normal individuals, C-peptide responses to OGTT showed less variation than IRI responses.
- Patients with insulin antibodies demonstrated significantly reduced C-peptide responses, which improved after antibody disappearance.
Conclusions:
- C-peptide offers a more consistent measure of insulin secretion compared to IRI, especially in the presence of insulin antibodies.
- Insulin antibodies can interfere with both IRI and C-peptide measurements by affecting insulin metabolism.
- Radioimmunoassay for C-peptide provides valuable supplementary information to insulin assays for evaluating insulin secretion in diabetes.
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