Dye coupling in the corneal endothelium : effects of ouabain and extracellular calcium removal

• Published in: Cell and tissue research Vol. 269; no. 1; pp. 57 - 63
• Main Authors: WATSKY, M. A, RAE, J. L
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01-07-1992
• Subjects: Animals; Biological and medical sciences; Calcium - metabolism; Cell Communication; Cells, Cultured; Endothelium, Corneal - drug effects; Endothelium, Corneal - metabolism; Eye and associated structures. Visual pathways and centers. Vision; Fundamental and applied biological sciences. Psychology; Intercellular Junctions - metabolism; Isoquinolines; Microinjections; Ouabain - pharmacology; Rabbits; Vertebrates: nervous system and sense organs; Cornea; Calcium; Cell junction; Rabbit; Cell cell interaction; Lagomorpha; Extracellular; Gap junction; Endothelium; Eye; Visual system; Vertebrata; Mammalia
• ISSN: 0302-766X; 1432-0878
• DOI: 10.1007/BF00384726

The effects of ouabain and extracellular calcium removal on gap junctional coupling of isolated rabbit corneal endothelium was examined using a modified dye-spread technique. This technique is a modification of a microelectrode procedure that now utilizes patch electrodes connected to a current-clamp circuit for dye iontophoresis and a shuttering system in the excitation light path to reduce phototoxic effects in the monolayer. It was found that a significant degree of junctional uncoupling occurred after 45 min of exposure to ouabain, quantified as a reduction in the effective diffusion coefficient of injected Lucifer yellow CH: 1.74 x 10(-7) cm2/s (control) versus 0.43 x 10(-7) cm2/s (ouabain-treated). It was also determined that no gap junctional uncoupling occurs after extended exposure (up to 3.5 h) to a calcium-free extracellular environment.