ENHANCING FLUID SECRETION BY CORNEAL EPITHELIUM

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  • 1 January 1977
    • journal article
    • research article
    • Vol. 16  (10) , 968-973
Abstract
Swollen rabbit corneas incubated in vitro with their posterior surfaces blocked with silicone oil maintained fairly constant thickness over an 11 h period. Increasing the simulated intraocular pressure from 10 to 30 mm Hg did not produce stromal thinning. When theophylline was added to stimulate epithelial Cl- secretion by increasing the Cl- permeability of the tear-facing epithelial membrane, corneas thinned at the average rate of 1.3 .mu.m/h over a 6.5 h period. When the epithelial perfusion solution was made Cl--free by SO42-substitution to favor the passive flow of Cl- from the cells to the tear solution, thinning of 3.91 .mu.m/h over a 7 h period was observed. When corneas were perfused with Cl--free medium plus theophylline, thinning at the average rate of 6.20 .mu.m/h over an 8 h period was achieved. The corneal epithelium is capable of thinning a swollen stroma by transport of fluid coupled to its Cl- secretion, which can be enhanced by simple substitutions in the tear-side bathing solution.