Simultaneous detection of intracellular free calcium and zinc using fura-2FF and FluoZin-3.

Journal Article (Journal Article)

Elevation of intracellular free zinc ([Zn2+]i) probably contributes to cell death in injury paradigms involving calcium deregulation and oxidative stress such as glutamate excitotoxicity. However, it is difficult to monitor both ions simultaneously in live cells. Here we present a new method using fluorescence microscopy and the ion sensitive indicators fura-2FF and FluoZin-3 to monitor both [Ca2+]i and [Zn2+]i in primary cortical neurons. We show that the new single wavelength dye FluoZin-3 responds robustly to small zinc loads, is insensitive to high Ca2+ or Mg2+, and is relatively unaffected by low pH or oxidants. The ratiometric indicator fura-2FF is sensitive to both Ca2+ and Zn2+. However, in conditions analogous to excitotoxic glutamate exposure where [Ca2+]i is high relative to [Zn2+]i, we found that fura-2FF responds mostly to [Ca2+]i but is relatively unaffected by low [Zn2+]i. Moreover, fura-2FF ratio changes caused by high [Ca2+]i or high [Zn2+]i could be distinguished because each ion produces a different spectral response. Finally, dual dye experiments showed that FluoZin-3 and fura-2FF respond robustly to [Zn2+]i and [Ca2+]j, respectively, in the same neurons during intense glutamate exposure. These studies provide a novel method for the simultaneous detection of both calcium and zinc in cells.

Full Text

Duke Authors

Cited Authors

  • Devinney, MJ; Reynolds, IJ; Dineley, KE

Published Date

  • March 2005

Published In

Volume / Issue

  • 37 / 3

Start / End Page

  • 225 - 232

PubMed ID

  • 15670869

Pubmed Central ID

  • 15670869

International Standard Serial Number (ISSN)

  • 0143-4160

Digital Object Identifier (DOI)

  • 10.1016/j.ceca.2004.10.003

Language

  • eng

Conference Location

  • Netherlands