Summary
Glucose, glucagon, tolbutamide and L-leucine stimulated insulin secretion from rabbit pancreas studiedin vitro. In each case stimulation was inhibited by omitting calcium from the incubation medium. The omission of magnesium had no effect on glucose stimulated insulin secretion but 10 mM magnesium inhibited secretion. Optimal secretion of insulin occurred at an extracellular calcium concentration of 2.64 mM. The omission of calcium inhibited glucose-stimulated insulin secretion from pancreas of 27 day rabbit foetuses.
Résumé
Le glucose, le glucagon, le tolbutamide et la L-leucine stimulent la libération d'insuline par le pancréas de lapin étudié in vitro. Cette stimulation n'a pas lieu lorsque le milieu d'incubation est préparé sans calcium. L'absence de magnésium n'a pas d'effet sur la sécrétion insulinique stimulée par le glucose, alors que le magnésium à la concentration de 10mM exerce un effet inhibiteur. La concentration optimale du calcium extracellulaire pour la sécrétion insulinique est de 2.64 mM. La stimulation de la sécrétion insulinique par le glucose est également supprimée par l'absence de calcium pour le pancréas de foetus de lapin âgé de 27 jours.
Zusammenfassung
Die Freisetzung von Insulin aus Kaninchen-Pankreas in vitro wird durch Glucose, Glucagon, Tolbutamid oder L-Leucin stimuliert. In allen diesen Fällen bleibt die Stimulation in Abwesenheit von Calcium in Inkubationsmedium aus. In Abwesenheit von Magnesium stimulierte Glucose die Insulinsekretion weiter, währenddem eine Erhöhung der Magnesiumkonzentration auf 10 mM deutlich hemmend wirkte. Die optimale Sekretion von Insulin erfolgte bei einer Calciumkonzentration von 2.64 mM. In Abwesenheit von Calcium wurde die Freisetzung von Insulin auch aus dem Pankreas von 27 Tage alten Foeten gehemmt.
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Milner, R.D.G., Hales, C.N. The role of calcium and magnesium in insulin secretion from rabbit pancreas studied in vitro. Diabetologia 3, 47–49 (1967). https://doi.org/10.1007/BF01269910
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DOI: https://doi.org/10.1007/BF01269910