C-peptide
How GLP-1 receptor agonists work — receptors, gastric emptying, and the satiety pathway.
Definition
A protein fragment released by the pancreas in 1:1 ratio with endogenous insulin. Used clinically to distinguish patients still producing insulin (type 2 diabetes, prediabetes) from those who are not (type 1 diabetes, end-stage type 2). GLP-1 agonists work by augmenting endogenous insulin secretion — patients with very low C-peptide (<0.6 ng/mL) typically respond poorly, which is one reason GLP-1s are FDA-labeled for type 2 (not type 1) diabetes.
Definition curated by Weight Loss Rankings — sourced from FDA labels and peer-reviewed PubMed literature, never AI-generated summaries.
Related terms in Mechanism
- GLP-1 receptor
- GIP receptor
- Dual agonist
- Gastric emptying
- Food noise
- Triple agonist
- Amylin
- GLP-1 tachyphylaxis
- Non-peptide GLP-1 agonist
- A1C (glycated hemoglobin)
- MASH / MASLD
- TBWL (Total Body Weight Loss)
- eGFR (estimated glomerular filtration rate)
- Visceral adipose tissue (VAT)
- AHI (apnea-hypopnea index)
- SNAC (oral semaglutide absorption enhancer)
Looking for more depth?
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- Browse the full GLP-1 glossary (124 terms across 8 categories)
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