The flux of glucose at the anterior stromal surface of the cornea is 575 nanomol/sq cm/hr in anesthetized rabbits. Blockade of the endothelial surface with air and silicone oil reduces the glucose flux to less than 20% of normal, reflecting the small amount of glucose which is available to the epithelium from the limbus. Blood in the anterior chamber reduces the flux to about 50% of normal. Interference with normal endothelial function by mechanical or thermal damage increases the movement of glucose across the cornea, which may indicate that the endothelium ordinarily acts as a relative permeability barrier to glucose penetration from the aqueous humor into the corneal stroma.
Thoft RA, Friend J, Dohlman CH. Corneal Glucose FluxII. Its Response to Anterior Chamber Blockade and Endothelial Damage. Arch Ophthalmol. 1971;86(6):685-691. doi:10.1001/archopht.1971.01000010687013