ABSTRACT
This chapter presents a synopsis of what is known about the physiology of lens junctions. It includes fiber-fiber, fiber-epithelial, and epithelial-epithelial junctions. A. I. Cohen used transmission electron micrographs to describe cell-to-cell junctions between fiber cells in mouse lenses. He was the first to suggest that such junctions might be involved in cell-to-cell movement of electric current and render the lens essentially syncytial. Only the quantitative measurements on fiber-fiber junctions have utilized electrical techniques. While several papers have presented the results of dye injections utilizing optical techniques, these have been entirely qualitative. One anticipates that it will be very difficult to quantitate dye spread in the lens because of the difficulty with out-of-plane fluorescence. Electrical measurements provided quantitative estimates of the extent of electrical coupling in several lens types. Very little is known about the extent of coupling between the epithelium and fiber cells of any lens.
