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Updated: Jul 18, 2026
12:33
A Method for Mouse Pancreatic Islet Isolation and Intracellular cAMP Determination
Published on: June 25, 2014
Nutrient control of insulin secretion in isolated normal human islets
Jean-Claude Henquin1, Denis Dufrane, Myriam Nenquin
1Unité d'Endocrinologie et Métabolisme, UCL 55.30, Ave. Hippocrate 55, B-1200 Brussels, Belgium. henquin@endo.ucl.ac.be
Diabetes
|November 30, 2006
Summary
Human pancreatic islets show robust nutrient-induced insulin secretion, similar to rodent models but with unique nutrient influences. This study characterizes glucose and amino acid effects on insulin release from human islets.
Area of Science:
- Endocrinology
- Metabolism
- Cell Biology
Background:
- Pancreatic islets regulate blood glucose by secreting insulin.
- Understanding nutrient-stimulated insulin secretion is crucial for diabetes research.
Purpose of the Study:
- To characterize nutrient-induced insulin secretion in human pancreatic islets.
- To compare human islet function with rodent models.
Main Methods:
- Isolation and culture of human pancreatic islets from organ donors.
- Perifusion experiments to measure insulin secretion in response to various nutrients.
- Pharmacological manipulation of ATP-sensitive K(+) channels.
Main Results:
- Glucose evoked concentration-dependent, biphasic insulin secretion with specific kinetic parameters (K(m), V(max)).
- ATP-sensitive K(+) channels play a key role, modulated by diazoxide and tolbutamide.
- Amino acids (glutamine, leucine, BCH, arginine) significantly influenced insulin secretion, often potentiated by glucose.
Conclusions:
- Human islet nutrient-induced insulin secretion is substantial and shares similarities with rodent islets.
- Distinct nutrient patterns, especially amino acids, affect human islet function within physiological glucose ranges.
- Both triggering and amplifying pathways are operative in human islets.
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