The effect of vitreous humor on fluid transport by rabbit corneal endothelium

The effects of vitreous humor and some of its components on the function of rabbit corneal endothelium were investigated and compared to those of artificial and natural aqueous humor. The rate of fluid pumping across the endothelium was measured while that layer was in contact with: (1) complete medium, an artificial aqueous solution; (2) pooled rabbit aqueous humor; (3) filtered and (4) unfiltered pooled rabbit vitreous humor; and (5) solid residue from vitreous humor. The relative magnitudes of the rates were: complete medium greater than aqueous larger than or equal to filtered vitreous greater than vitreous larger than or equal to solid residue. A definite adverse effect of unfiltered vitreous and of its solid residue on endothelial pumping was observed. It is suggested that the solid (collagenous) elements in vitreous humor may be responsible for these effects and perhaps for those generically referred to as the "vitreous touch syndrome" in clinical studies.