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A Method for Mouse Pancreatic Islet Isolation and Intracellular cAMP Determination
Published on: June 25, 2014
Insulin secretion and insulin-producing tumors
Jean-Marc Guettier1, Phillip Gorden
1National Institute of Diabetes and Digestive and Kidney Diseases, Building 10-CRC, Room 6-5952, 10 Center Drive, Bethesda, MD 20892-1612, USA, Tel.: +1 301 496 1913, , guettierj@mail.nih.gov.
Expert Review of Endocrinology & Metabolism
|April 20, 2010
Summary
Insulinomas, rare pancreatic tumors, cause fasting hypoglycemia by overproducing insulin. Surgical resection offers a cure for most patients with this condition.
Area of Science:
- Endocrinology
- Oncology
- Cell Biology
Background:
- Insulinomas are rare neuroendocrine tumors originating from pancreatic islet cells.
- These tumors autonomously produce and secrete insulin and proinsulin, even at low blood glucose levels.
- This leads to clinical manifestations of fasting hypoglycemia.
Purpose of the Study:
- To review the molecular pathways of normal insulin secretion and beta-cell growth.
- To contrast these pathways with the biology of insulinomas.
- To summarize the clinical approach to diagnosing and managing insulinomas.
Main Methods:
- Review of molecular pathways governing insulin secretion and beta-cell growth.
- Clinical review of diagnostic and localization strategies for insulinomas.
- Emphasis on supervised fasting protocols for diagnosis.
Main Results:
- Insulinoma cells exhibit deregulated insulin secretion independent of blood glucose levels.
- Diagnosis relies on identifying inappropriately high insulin during hypoglycemia.
- Localization can be challenging due to tumor size, impacting surgical planning.
Conclusions:
- Successful surgical resection is the primary curative treatment for insulinomas.
- Early and accurate diagnosis and localization are crucial for optimal surgical outcomes.
- Most patients achieve a lifelong cure after successful surgical removal.
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