Morphological change and Raman spectrum of rabbit lens irradiated with ultraviolet laser beam

The effect of ultraviolet rays on eyes was studied. An ultraviolet laser beam (XeCl 308 nm) was irradiated to rabbit eyes to investigate morphological changes of the lens fibers and molecular structural changes of the lens proteins at immediately, 15 days and 32 days after irradiation. 1. Scanning electron microscopic findings of the lens The lens fibers in the control eye were regularly and densely arranged in neat layers of hexahedrons. In the irradiated eye, the fibers at areas that seemed injured were disrupted and the disrupted ends were spherical-shaped. 2. Raman spectra of the lens 1) The relative intensity ratio (I825/I850) of the Raman scattering for the tyrosine residue and the relative intensity ratio (I3390/I2960) of the OH stretching mode (3390 cm-1) of water contained in the lens cortex showed slight changes in the irradiated eye compared to the control eye. 2) The relative intensity ratio (I2572/I2721) of the SH stretching mode (2572 cm-1) for the cysteine residue was 1.05 in the irradiated eye at 32 days after irradiation. It was lower than that in the control eye (1.22 +/- 0.08). This suggested the synthesis of S-S binding by oxidization.