Control of mitochondrial matrix calcium: Studies using fluo-3 as a fluorescent calcium indicator

doi:10.1016/0006-291X(90)91743-C

Biochemical and Biophysical Research Communications

Volume 167, Issue 1, 28 February 1990, Pages 148-153

https://doi.org/10.1016/0006-291X(90)91743-C Get rights and content

Abstract

Fluo-3, a fluorescent Ca²⁺ indicator, is sequestered by isolated rat liver mitochondria and is an effective probe for evaluating the concentration and kinetics of change of mitochondrial matrix ionized calcium ([Ca²⁺]m) under a variety of conditions. At the wavelengths employed, there is no significant interference by auto-fluorescence. There is an insignificant release of the indicator over four hours and the loading and presence of fluo-3 has no effect on respiratory rate or oxidative phosphorylation. The [Ca²⁺]m steady state can be altered by the assay conditions, i.e. the presence of extramitochondrial Ca²⁺, Mg²⁺, phosphate and respiratory inhibitors. The total matrix ionized calcium represents a small percent (<0.01%) of the total mitochondrial calcium.

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Control of mitochondrial matrix calcium: Studies using fluo-3 as a fluorescent calcium indicator

Abstract

Curr. Top. Membr. Transp

J. Biol. Chem

Biochem. Biophys. Res. Commun

Biochim. Biophys. Acta

J. Biol. Chem

J. Biol. Chem

Biochim. Biophys. Acta