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Published on: April 20, 2017
Human gastrinoma cells express calcium-sensing receptor
1Department of Surgery and Surgical Basic Science, Graduate School of Medicine, Kyoto University, Japan. itami@kuhp.kyoto-u.ac.jp
Life Sciences
|January 15, 2002
Summary
The calcium-sensing receptor (CaR) plays a key role in how gastrinoma cells release gastrin when exposed to calcium. This finding clarifies the mechanism behind calcium-stimulated gastrin release.
Area of Science:
- Endocrinology
- Cell Biology
- Oncology
Background:
- The intravenous calcium injection test aids gastrinoma diagnosis.
- The precise mechanism of calcium-induced gastrin release remains unclear.
Purpose of the Study:
- To investigate the mechanism of calcium-stimulated gastrin release from gastrinoma cells.
- To determine the role of the calcium-sensing receptor (CaR) in this process.
Main Methods:
- Human gastrinoma cells were isolated and studied in a perifusion system.
- Gastrin release, intracellular calcium levels, and CaR gene expression were analyzed.
- Immunohistochemistry confirmed CaR expression in gastrinoma tissues.
Main Results:
- High extracellular calcium ([Ca2+]o) stimulated gastrin release from gastrinoma cells.
- Increased [Ca2+]o led to a rapid rise in intracellular calcium ([Ca2+]i).
- The calcium-sensing receptor (CaR) gene was present and expressed in gastrinoma tissues.
Conclusions:
- The calcium-sensing receptor (CaR) is expressed in human gastrinoma cells.
- CaR is likely involved in the mechanism of calcium-evoked gastrin release.
- This study provides insights into the diagnostic utility of calcium tests for gastrinoma.
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