Gaps between lens epithelial cells due to contractions

Abstract

AbstractPurpose The purpose of the study was to characterize the contractions of human anterior lens capsule epithelial cells that create gaps between cells, and to assess the physiological mechanisms and a possible association of the contractions with cataract formation.Methods Lens capsules obtained during cataract surgery were stained with fluorescent dye Fura‐2. Its fluorescence, upon excitation at 360 and 380 nm, was imaged to monitor changes in cell morphology and cytosolic free Ca2+ concentrations ([Ca2+]i) in response to pharmacological stimulation by acetylcholine and to mechanical stimulation. Contractions were also studied by scanning electron microscope.Results Epithelial cells contracted in about a third of preparations after stimulation. Contractions started either before or at best simultaneously with the rise in [Ca2+]i. They also occurred when there was hardly any change in [Ca2+]i upon application of physiological saline alone. The probability of contractions occurring did not differ significantly among cortical, nuclear and combined cortical+nuclear cataract.Conclusion The contractions of the anterior lens epithelial cells occur in significant part of human lens anterior capsule postoperative preparations. They can be mechanically induced, are localized and reversible, have a fast response and did not differ among different types of cataract. They are at least partly independent of changes in [Ca2+]i. This mechanism could represent physiological basis of cataract formation in phakic intraocular lenses that touch the crystalline lens.