Galanin message-associated polypeptide (GMAP) does not affect insulin secretion from isolated islets.

S Gregersen; U Langel; T Bartfai; B Ahrén

doi:10.1016/0014-2999(94)90161-9

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Galanin message-associated polypeptide (GMAP) does not affect insulin secretion from isolated islets.

S Gregersen·U Langel·T Bartfai·B Ahrén

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Abstract

Galanin message-associated polypeptide (GMAP) is processed from preprogalanin. Recently, GMAP-like immunoreactivity was demonstrated in insulin cells in the endocrine pancreas. We therefore examined whether synthetic rat GMAP, like galanin, inhibits glucose-stimulated insulin secretion from isolated rat and mouse islets. We found, however, that over a wide dose range (0.1 nM to 1 microM) GMAP did not affect insulin secretion stimulated by 8.3 or 11.1 mM glucose during a 60-min incubation of single rat or mouse islets. In contrast, rat galanin, as expected, completely abolished glucose-stimulated insulin secretion at 100 nM. Thus, in contrast to galanin, GMAP does not affect insulin secretion in isolated rodent islets.

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Amino Acid Sequence Animals Female Galanin In Vitro Techniques Insulin Insulin Secretion Islets of Langerhans Male Mice Molecular Sequence Data Peptides Protein Precursors Rats Journal Article Research Support, Non-U.S. Gov't

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S Gregersen, U Langel, T Bartfai, B Ahrén. 1994-06-23. Galanin message-associated polypeptide (GMAP) does not affect insulin secretion from isolated islets.. https://doi.org/10.1016/0014-2999(94)90161-9

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