Nonspecific Depolarization of the Plasma Membrane Potential Induces Cytoskeletal Modifications of Bovine Corneal Endothelial Cells in Culture

doi:10.1006/excr.2002.5664

Experimental Cell Research

Volume 282, Issue 1, 1 January 2003, Pages 1-13

https://doi.org/10.1006/excr.2002.5664 Get rights and content

Abstract

Modifications in the cell membrane potential have been suggested to affect signaling mechanisms participating in diverse cellular processes, many of which involve structural cellular alterations. In order to contribute some evidence in this respect, we explored the effects of several depolarizing procedures on the structure and monolayer organization of bovine corneal endothelial cells in culture. Visually confluent cell monolayers were incubated with or without the depolarizing agent, either in a saline solution or in culture medium for up to 30 min. Membrane potential was monitored by fluorescence microscopy using oxonol V. Fluorescent probes were employed for F-actin, microtubules, and vinculin. Depolarization of the plasma membrane, achieved via the incorporation of gramicidin D into confluent endothelial cells or by modifications of the extracellular saline composition, provoked an increment of oxonol fluorescence and changes in cell morphology, consisting mainly of modifications in the cytoskeletal organization. In some areas, noticeable intercellular spaces appear. The cytoskeleton modifications mainly consist of a marked redistribution of F-actin and microtubules, with accompanying changes in vinculin localization. The results suggest that the depolarization of the plasma membrane potential may participate in mechanisms involved in cytoskeleton organization and monolayer continuity in corneal endothelial cells in culture.

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Regular ArticleNonspecific Depolarization of the Plasma Membrane Potential Induces Cytoskeletal Modifications of Bovine Corneal Endothelial Cells in Culture

Abstract

Curr. Opin. Genet. Dev.

Curr. Opin. Cell Biol.

Curr. Opin. Cell Biol.

Methods Enzymol.

Methods Enzymol.

Bone

Biochim. Biophys. Acta

Curr. Opin. Cell Biol.

Epithelial organization

Morphogenesis of the polarized epithelial cell phenotype

Science

New perspectives on mechanisms involved in generating epithelial cell polarity

Physiol. Rev.

Transport across cell membranes

Molecular Cell Biology

Electric fields at the plasma membrane level: A neglected element in the mechanisms of cell signalling

BioEssays

Functional significance of cell volume regulatory mechanisms

Physiol. Rev.

Modeling cell volume regulation in nonexcitable cells: The roles of the Na+ pump and of cotransport systems

Am. J. Physiol.

Electrical coupling between smooth muscle cells and endothelial cells in pig coronary arteries

Pflugers Arch.

Simultaneous oscillations in the membrane potential of pig coronary artery endothelial and smooth muscle cells

J. Physiol. (Lond.)

Pathways controlling healthy and diseased arterial smooth muscle

Am. J. Cardiol.

The role of the membrane potential of endothelial and smooth muscle cells in the regulation of coronary blood flow

J. Cardiovasc. Electrophysiol.

Endothelium–smooth muscle interactions in blood vessels

Clin. Exp. Pharmacol. Physiol.

Fluid transport and electroosmosis across corneal endothelium

Cellular and monolayer structural modifications induced by gramicidin in bovine corneal endothelial cells in culture

Invest. Ophthalmol. Vis. Sci.

Monolayer organization by serially cultured bovine corneal endothelial cells: Effects of a retina-derived growth-promoting activity

Exp. Eye Res.

Membrane potential changes visualized in complete growth media through confocal laser scanning microscopy of bis-oxonol-loaded cells

Exp. Cell Res.

Regular Article
Nonspecific Depolarization of the Plasma Membrane Potential Induces Cytoskeletal Modifications of Bovine Corneal Endothelial Cells in Culture

Modeling cell volume regulation in nonexcitable cells: The roles of the Na⁺ pump and of cotransport systems