Diffusion of oxygen at the endothelial surface of the rabbit cornea

1. An in vitro investigation was made to determine the oxygen tension level required at the endothelial surface of rabbit cornea to produce a net oxygen flux into the cornea across this surface when the epithelial surface was exposed to air. 2. The experimental design was based on a mathematical model which showed that the direction of oxygen flux measured in an agar layer adjacent to the endothelium was the same as the direction of oxygen flux across the endothelial surface. 3. From micro-electrode measurements of oxygen tension in the agar layer, it was found that an oxygen tension greater than 102 mmHg at the endothelial surface was required tocause a net flux of oxygen into the cornea. 4. Comparing this result to the in vivo situation,it was concluded that all layers of the rabbit cornea receive oxygen from the atmosphere under open eye conditions.