Ca2+ triggers massive exocytosis in Chinese hamster ovary cells

EMBO J. 1996 Aug 1;15(15):3787-91.

Abstract

We have tracked the cell surface area of CHO cells by measuring the membrane capacitance, Cm. An increase in cytosolic [Ca2+], [Ca2+]i, increased the cell surface area by 20-30%. At micromolar [Ca2+]i the increase occurred in minutes, while at 20 microM or higher [Ca2+]i it occurred in seconds and was transient. GTPgammaS caused a 3% increase even at 0.1 microM [Ca2+]i. We conclude that CHO cells, previously thought capable only of constitutive exocytosis, can perform Ca2+-triggered exocytosis that is both massive and rapid. Ca2+-triggered exocytosis was also observed in 3T3 fibroblasts. Our findings add evidence to the view that Ca induces exocytosis in cells other than known secretory cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Calcium / physiology*
  • Cricetinae
  • Cricetulus
  • Exocytosis* / drug effects
  • Female
  • Guanosine 5'-O-(3-Thiotriphosphate) / pharmacology
  • Magnesium / pharmacology
  • Ovary / cytology
  • Ovary / drug effects
  • Ovary / metabolism*
  • Photolysis

Substances

  • Guanosine 5'-O-(3-Thiotriphosphate)
  • Magnesium
  • Calcium