The role of the corneal epithelium in regulating the concentration of glucose in the underlying stroma was investigated in rabbits. In some animals the epithelium was scraped off for 24 hours, and the glucose concentration and glucose gradient in such corneas was not found to be significantly different from those values found in normal corneas. Using a chamber to apply artificial tear solution to the bare corneal stroma, thereby maximizing leaching, it was found that the concentrations of glucose in the anterior and posterior stromal layers were substantially lower than normal. Additional experiments measured glucose flux across the front of the cornea in the presence and absence of epithelium and showed that the maximal glucose flux present at the anterior stromal surface is not in great excess of the epithelial nutritional requirements.
Thoft RA, Friend J, Dohlman CH. Corneal Glucose ConcentrationFlux in the Presence and Absence of Epithelium. Arch Ophthalmol. 1971;85(4):467-472. doi:10.1001/archopht.1971.00990050469013