Measurements of cytoplasmic free Ca2+ concentration in human pancreatic islets and insulinoma cells

FEBS Lett. 1991 Oct 21;291(2):310-4. doi: 10.1016/0014-5793(91)81309-v.


In human pancreatic islets an increase in the glucose concentration from 3 to 20 mM raised the free cytoplasmic Ca2+ concentration [( Ca2+]i), an effect being reversible upon withdrawal of the sugar. Depolarization with a high concentration of K+ or the sulphonylurea tolbutamide also raised [Ca2+]i. Addition of extracellular ATP produced a transient rapid rise in [Ca2+]i. Oscillations in [Ca2+]i were observed in the presence of 10 mM glucose. Insulinoma cells responded to glucose and tolbutamide with increases in [Ca2+]i, whereas the sulphonamide diazoxide caused a decrease in [Ca2+]i. These findings confirm previous results obtained in rodent beta-cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Calcium / chemistry*
  • Cytoplasm / chemistry*
  • Female
  • Fura-2
  • Humans
  • Insulinoma / chemistry*
  • Insulinoma / pathology
  • Islets of Langerhans / chemistry*
  • Male
  • Tumor Cells, Cultured


  • Calcium
  • Fura-2