Glucose-induced oscillations of cytoplasmic Ca2+ in the pancreatic beta-cell

Biochem Biophys Res Commun. 1988 Mar 30;151(3):1299-304. doi: 10.1016/s0006-291x(88)80503-5.

Abstract

The cytoplasmic calcium concentration (Ca2+i) was measured in individual mouse pancreatic beta-cells loaded with fura-2 by recording the 340/380 nm fluorescence excitation ratio. An increase of the glucose concentration from 3 to 20 mM, caused initial lowering of Ca2+i followed by a rise with a peak preceding constant elevation at an intermediary level. However, at 11 mM glucose there were large Ca2+i oscillations with a frequency of 1 cycle per 2-6 min. The results indicate that both first and second phase secretion depend on elevated Ca2+i, and that many electrically coupled cells collectively determine the pace of rhythmic depolarization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benzofurans
  • Cytoplasm / drug effects
  • Cytoplasm / metabolism*
  • Fura-2
  • Glucose / pharmacology*
  • Islets of Langerhans / cytology*
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / metabolism
  • Mice
  • Mice, Obese

Substances

  • Benzofurans
  • Glucose
  • Fura-2