Isolated human and rabbit eye: Models of corneal toxicity

Human and rabbit isolated eyes were compared, not in order to propose yet another test, but to explore the boundaries of the rabbit isolated cornea as a model for primary damage to human cornea. Changes in corneal thickness and in epithelial morphology were followed on recovery from cold-induced oedema and after exposure to the test chemicals. There was no statistical difference between control human and rabbit eyes in recovery from severe oedema. The effects of exposure to allyl alcohol, Arlagard E, NaOH (1 N), NaCl, sodium lauryl sulphate (2%) and Tween-20 were similar in human and rabbit eyes. Acetone, ethanol and glycerol had opposed-sign effects on corneal thickness in human and rabbit. From the small number of substances tested it can be concluded qualitatively that stored rabbit eyes behave in a manner similar to freshly isolated rabbit eyes, and that substances in which penetration depends on surface properties of the cornea may have species-specific effects.