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Mixed Primary Cultures of Murine Small Intestine Intended for the Study of Gut Hormone Secretion and Live Cell Imaging of Enteroendocrine Cells
Published on: April 20, 2017
Electrical activity-triggered glucagon-like peptide-1 secretion from primary murine L-cells
G J Rogers1, G Tolhurst, A Ramzan
1Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke's Hospital, Box 139, Hills Road, Cambridge CB2 0XY, UK.
The Journal of Physiology
|January 13, 2011
Summary
Glucagon-like peptide 1 (GLP-1) release from intestinal L-cells is driven by electrical activity. Voltage-gated sodium and calcium channels are crucial for regulating GLP-1 secretion, offering new therapeutic targets for diabetes.
Area of Science:
- Endocrinology
- Cell Physiology
- Molecular Biology
Background:
- Glucagon-like peptide 1 (GLP-1) therapies are vital for type 2 diabetes management.
- Understanding intestinal L-cell function is key to developing novel GLP-1-based treatments.
Purpose of the Study:
- To characterize the electrical activity of primary L-cells.
- To determine the role of voltage-gated sodium and calcium channels in GLP-1 secretion.
Main Methods:
- Primary murine L-cells were identified and purified using fluorescent reporters.
- Patch clamp electrophysiology was used to record electrical activity.
- GLP-1 secretion, gene expression (microarray, RT-PCR) were measured.
Main Results:
- L-cells exhibit significant voltage-gated sodium currents, essential for basal and stimulated GLP-1 secretion.
- L-type, Q-type, and T-type calcium channels are involved in GLP-1 release.
- Potassium currents were observed, with a minor chromanol-sensitive component.
Conclusions:
- GLP-1 secretion from L-cells is intrinsically linked to their electrical activity.
- Activation of specific calcium channel types (L-type, Q-type) is critical for GLP-1 release.
- The electrically excitable nature of L-cells provides a framework for modulating GLP-1 release via various stimuli.
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