Regional distribution of mammalian corneal aldehyde dehydrogenase and alcohol dehydrogenase.

The regional distribution of mouse aldehyde dehydrogenase (ALDH) and alcohol dehydrogenase activities in mouse ocular tissues was examined using spectrophotometric and agarose-isoelectric focusing techniques. The results established that these enzymes are predominantly localized in the cornea. Biochemical and histochemical analyses of the localization of these enzymes in the corneas of common domestic mammals (pigs, sheep, and cattle) and in baboons revealed species differences, with high levels being reported in corneal epithelium (pigs and baboons) and endothelium (sheep and cattle). The presence of these enzymes in the corneal epithelium is consistent with their proposed catalytic role in the detoxification of ultraviolet (UV)-induced peroxidic aldehydes, and with the proposed role for corneal ALDH in UVB absorption.