Hasan GENÇOĞLU, Peter M. JONES, Kazim ŞAHİN

Determining the insulin secretion potential for certain specific G-protein coupled receptors in MIN6 pancreatic beta cells

Background/aim: The polypeptide hormone insulin is essential for the maintenance of whole-body fuel homeostasis, and defects ininsulin secretion and/or action are associated with the development of type 1 and type 2 diabetes. The aim of this study was to assessthe role of some G-protein coupled receptors (GPCRs), GPR54, GPR56, and GPR75, and cannabinoid receptors CB1R and CB2R, inthe regulation of pancreatic β-cell function.Materials and methods: Insulin secretion from mouse insulinoma β-cell line (MIN6) monolayers was assessed via insulin radioimmunoassay (RIA). Reverse transcription-polymerase chain reaction (RT-PCR) was used to assess the expression of some specific GPCRsand the other receptors by MIN6 pancreatic β-cells.Results: The agonists were not found to be toxic for the MIN6 pancreatic β-cells within the range of the doses used in this study, whereasinsulin secretion altered depending on the ligands and receptors. In addition, arachidonyl-2’-chloroethylamide (ACEA), carbachol,chemokine (C-C motif) ligand-5 (CCL5), and exendin as well as phorbol myristate acetate (PMA) ligands showed significant increasesin the insulin secretion of MIN6 pancreatic β-cells.Conclusion: Understanding the normal β-cell function and identifying the defects in β-cell function that lead to the development ofdiabetes will generate new therapeutic targets.

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