Synchronous glucose-dependent [Ca(2+)](i) oscillations in mouse pancreatic islets of Langerhans recorded in vivo

FEBS Lett. 2000 Jul 14;477(1-2):33-6. doi: 10.1016/s0014-5793(00)01631-8.

Abstract

Using microfluorescence in combination with image-analysis techniques we monitored intracellular calcium ([Ca(2+)](i)) dynamics in mouse islets of Langerhans loaded with fura-2 and recorded in vivo. [Ca(2+)](i) oscillates in the glycaemias range 5-10 mM, the duration of the oscillations being directly proportional to the blood glucose concentration. The analysis of different areas within the same islet shows that [Ca(2+)](i) oscillations are synchronous throughout the islet. These results show that in vivo, individual islets of Langerhans behave as a functional syncytium and suggest the existence of secretory pulses of insulin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Glucose / metabolism
  • Calcium / metabolism*
  • Calcium Signaling / drug effects
  • Fluorescence
  • Fura-2 / metabolism
  • Glucose / metabolism
  • Glucose / pharmacology*
  • Islets of Langerhans / drug effects*
  • Islets of Langerhans / metabolism*
  • Membrane Potentials / drug effects
  • Mice

Substances

  • Blood Glucose
  • Glucose
  • Calcium
  • Fura-2