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Updated: Aug 15, 2026

Simultaneous Measurement of Mitochondrial Calcium and Mitochondrial Membrane Potential in Live Cells by Fluorescent Microscopy
08:43

Simultaneous Measurement of Mitochondrial Calcium and Mitochondrial Membrane Potential in Live Cells by Fluorescent Microscopy

Published on: January 24, 2017

Transport of calcium by mitochondria

K K Gunter1, T E Gunter

  • 1Department of Biophysics, University of Rochester Medical School, New York 14642.

Journal of Bioenergetics and Biomembranes
|October 1, 1994
PubMed

Insights

Mitochondrial calcium transport mechanisms are crucial for cellular metabolism. This review details the energetics and kinetics of calcium transport across the inner mitochondrial membrane, including updated concepts.

Area of Science:

  • Mitochondrial Physiology
  • Cellular Metabolism
  • Biochemistry

Background:

  • Intramitochondrial free calcium ([Ca2+]m) is a key metabolic mediator.
  • Understanding mechanisms controlling [Ca2+]m is vital.

Purpose of the Study:

  • To update descriptions of Ca2+ transport mechanisms across the mitochondrial inner membrane.
  • To emphasize the energetics of each transport mechanism.
  • To review new and older concepts in mitochondrial calcium transport.

Main Methods:

  • Review of existing literature and recent evidence.
  • Mathematical interpolation of membrane potential and concentration dependence for the uniporter.
  • Analysis of energetics and stoichiometries of Ca2+ efflux mechanisms.

Main Results:

  • Updated descriptions of Ca2+ transport mechanisms.
  • Consideration of Vmax as an explicit function of membrane potential.
  • Discussion of a transient rapid conductance state of the uniporter.
  • Review of new evidence on Na(+)-dependent and Na(+)-independent efflux mechanisms.

Conclusions:

  • Explicit mathematical expressions are provided for energetics and kinetics.
  • The review offers a comprehensive update on mitochondrial calcium transport.
  • Highlights new concepts and provides deeper insights into older ones.

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