title: [Scanning microscopy study of the corneal epithelium. Relation of various aspects to the lacrimal film].
abstract: Cells of the superficial layer of the corneal epithelium demonstrate differences in luminosity on scanning electron microscopy which has led to their classification as clear, intermediate or dark cells, differences attributed to varying amounts of surface microvillosities. Evidence is provided confirming that differences between cells is not due to artefacts during preparation or observation of specimens. On the other hand, this technique cannot demonstrate whether different evolutory stages of the same cell are involved. Scanning microscopy cannot confirm a single evolutory epithelial cell are involved. Scanning microscopy cannot confirm a single evolutory epithelial cell cycle from the position of the cell in relation to adjacent desquamating cells, or the study of the cell nuclei. Nor can a satisfactory response to the problem be supplied by studying mucosubstances deposited by the lacrimal film on the surface of the epithelium, either by optical microscopy or after scanning electron microscopy with or without washing with acetylcysteine. The presence of superficial epithelial cells of different appearances on scanning microscopy must be due to variations in the amount of glycocalix, the mucus film adsorbed onto the cell surface.
mesh_terms: D000818:Animals; D002453:Cell Cycle; D003315:Cornea / Q000166:cytology / Q000648:ultrastructure*; D004847:Epithelial Cells; D004848:Epithelium / Q000648:ultrastructure; D006023:Glycoproteins / Q000032:analysis; D006801:Humans; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008871:Microvilli / Q000648:ultrastructure; D009093:Mucus / Q000032:analysis; D011134:Polysaccharides / Q000032:analysis; D011817:Rabbits; D013666:Tears / Q000032:analysis / Q000502:physiology*
chemical_list: D006023:Glycoproteins; D011134:Polysaccharides
vernacular_title: Etude en microscopie à balayage de l'épithélium cornéen. Relation de certains aspects avec le film lacrymal.