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A High-content In Vitro Pancreatic Islet β-cell Replication Discovery Platform
09:35

A High-content In Vitro Pancreatic Islet β-cell Replication Discovery Platform

Published on: July 16, 2016

Preptin derived from proinsulin-like growth factor II (proIGF-II) is secreted from pancreatic islet beta-cells and

C M Buchanan1, A R Phillips, G J Cooper

  • 1School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.

The Biochemical Journal
|November 22, 2001
PubMed

Pancreatic islet beta-cells secrete the hormones insulin, amylin and pancreastatin. To search for further beta-cell hormones, we purified peptides from secretory granules isolated from cultured murine beta TC6-F7 beta-cells. We identified a 34-amino-acid peptide (3948 Da), corresponding to Asp(69)-Leu(102) of the proinsulin-like growth factor II E-peptide, which we have termed 'preptin'. Preptin, is present in islet beta-cells and undergoes glucose-mediated co-secretion with insulin. Synthetic preptin increases insulin secretion from glucose-stimulated beta TC6-F7 cells in a concentration-dependent and saturable manner. Preptin infusion into the isolated, perfused rat pancreas increases the second phase of glucose-mediated insulin secretion by 30%, while anti-preptin immunoglobulin infusion decreases the first and second phases of insulin secretion by 29 and 26% respectively. These findings suggest that preptin is a physiological amplifier of glucose-mediated insulin secretion.

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