Relationship between various concentrations of NaOH and metabolic effects in experimentally burned rabbit cornea. A biochemical and histochemical study.

In order to assess the extent of injury and the response of the cornea to alkali burns, NaOH in concentrations of 0.5, 0.25, 0.1, 0.05, and 0.01 N was applied to rabbit eyes and the histologic and metabolic changes studied. The activities of alkaline and acid phosphatases in homogenates and in cold microtome sections were examined on days 1, 4, and 7 after injury. At all time intervals 0.5 N and 0.25 N NaOH induced a remarkable decrease in enzyme activities. On the other hand, after 0.05 N and 0.01 N NaOH only very slight changes were observed. Using 0.1 N NaOH, both phosphatases decreased on day 4 after treatment and acid phosphatase reached normal values in a week, whereas alkaline phosphatase increased with a maximum on day 7. Its role in synthetic processes during corneal regeneration is discussed. Both histologic and metabolic patterns in the experimentally burned cornea were shown to be a function of NaOH concentration and the duration of contact. The process of re-epithelization of the cornea during healing after 0.1 N NaOH for 1 min is described.