Membrane Potentials and Resistances of Giant Mitochondria: Metabolic Dependence and the Effects of Valinomycin

Authors

Bruce L. Maloff, University at Albany, State University of New York
Stylianos P. Scordilis, University at Albany, State University of New YorkFollow
Christopher Reynolds, University at Albany, State University of New York
Henry Tedeschi, University at Albany, State University of New York

Document Type

Article

Publication Date

7-1-1978

Publication Title

Journal of Cell Biology

Abstract

The membrane potentials and resistances of giant mitochondria from mice fed cuprizone have been studied. They were found to correspond approx. 10-20 mV, positive inside, and 2 M omega, respectively. These properties were found to be independent of the metabolic state. The microelectrodes were in the inner mitochondrial space since (a) the potentials in the presence of valinomycin depended on the K+ concentration of the medium and magnitude of the K+ diffusion potentials was consistent with the presence of a high internal concentration of K+, (b) almost identical results were obtained with mitochondria from which the external membrane had been removed and the cristae were evaginated, and (c) punch-through experiments, in which the microelectrodes were advanced until they emerged through the other side of the mitochondria, showed an identical membrane potential both in the presence and in the absence of valinomycin. The potentials were stable under a variety of conditions and showed no sign of decay of membrane leakiness. Detailed evidence that the impaled mitochondria are metabolically viable will be presented in a separate publication.

Keywords

mitochondrial potentials, microelectrodes, oxidative phosphorylation

Volume

78

Issue

1

First Page

199

Last Page

213

DOI

doi.org/10.1083/jcb.78.1.199

Rights

© The Rockefeller University Press

Comments

Archived as published.

Open access article.

Recommended Citation

Maloff, Bruce L.; Scordilis, Stylianos P.; Reynolds, Christopher; and Tedeschi, Henry, "Membrane Potentials and Resistances of Giant Mitochondria: Metabolic Dependence and the Effects of Valinomycin" (1978). Biological Sciences: Faculty Publications, Smith College, Northampton, MA.
https://scholarworks.smith.edu/bio_facpubs/149