Small Mouse Islets Are Deficient in Glucagon-Producing Alpha Cells but Rich in Somatostatin-Secreting Delta Cells.

J Diabetes Res

Department of Medical Cell Biology, Uppsala University, Box 571, 751 23 Uppsala, Sweden.

Published: June 2017

Small and big mouse islets were compared with special reference to their content of glucagon-producing α-cells and somatostatin-producing δ-cells. Areas stained for glucagon and somatostatin were measured in the largest cross section of small (diameter < 60 μm) and big (diameter > 100 μm) islets. Comparison of the areas indicated proportionally more δ- than α-cells in the small islets. After isolation with collagenase these islets were practically devoid of α-cells. We evaluated the functional importance of the islet size by measuring the Ca(2+) signal for insulin release. A majority of the small islets responded to the hyperpolarization action of somatostatin with periodic decrease of cytoplasmic Ca(2+) when glucose was elevated after tolbutamide blockade of the KATP channels.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4967688PMC
http://dx.doi.org/10.1155/2016/4930741DOI Listing

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