A Ringvold1. 1. University Eye Department, National Hospital Oslo, Norway.
Abstract
PURPOSE: To study UV-absorption and UV-induced fluorescence in the bovine corneal epithelium. METHODS: Spectrophotometry and spectrofluorimetry. RESULTS: The corneal epithelium absorbs UV-B radiation mainly owing to its content of protein, RNA, and ascorbate. Some of the absorbed energy is transformed to the less biotoxic UV-A radiation by fluorescence. RNA and ascorbate reduce tissue fluorescence. CONCLUSIONS: The corneal epithelium acts as a UV-filter, protecting internal eye structures through three different mechanisms: (1) Absorption of UV-B roughly below 310 nm wavelength. (2) Fluorescence-mediated ray transformation to longer wavelengths. (3) Fluorescence reduction. The extremely high ascorbate concentration in the corneal epithelium has a key role in two of these processes.
PURPOSE: To study UV-absorption and UV-induced fluorescence in the bovine corneal epithelium. METHODS: Spectrophotometry and spectrofluorimetry. RESULTS: The corneal epithelium absorbs UV-B radiation mainly owing to its content of protein, RNA, and ascorbate. Some of the absorbed energy is transformed to the less biotoxic UV-A radiation by fluorescence. RNA and ascorbate reduce tissue fluorescence. CONCLUSIONS: The corneal epithelium acts as a UV-filter, protecting internal eye structures through three different mechanisms: (1) Absorption of UV-B roughly below 310 nm wavelength. (2) Fluorescence-mediated ray transformation to longer wavelengths. (3) Fluorescence reduction. The extremely high ascorbate concentration in the corneal epithelium has a key role in two of these processes.
Authors: Natalie Lassen; J Bronwyn Bateman; Tia Estey; Jer R Kuszak; David W Nees; Joram Piatigorsky; Gregg Duester; Brian J Day; Jie Huang; Lisa M Hines; Vasilis Vasiliou Journal: J Biol Chem Date: 2007-06-13 Impact factor: 5.157