Dye coupling of rabbit ciliary epithelial cells in vitro.

This content is PDF only. Please click on the PDF icon to access.

Abstract

PURPOSE: To examine the in vitro properties of gap junctions on the isolated rabbit ciliary epithelium. METHODS: Intracellular potential was measured and lucifer yellow (5% in 1 M LiCl) was iontophoretically injected into a ciliary epithelial cell. Fixated tissue was examined with a laser confocal microscope. RESULTS: Dye spread was observed throughout both layers (horizontally and vertically) of the ciliary epithelium adjacent to the injected cell that was more intensely labeled. Dye reflux did not occur at the site of microimpalement. Microiontophoretic dye injection in a bathing solution with a high Ca2+ (10 mM) or an acidic pH (6.3) completely inhibited cell-cell dye coupling in the rabbit ciliary epithelial cells. CONCLUSIONS: Laser confocal microscopy of intracellularly injected lucifer yellow dye demonstrates the physiologic presence of gap junctions between both ciliary epithelial layers. Extracellular acidosis and high concentration of extracellular Ca2+ cause loss of cell-cell coupling in the rabbit ciliary epithelium.