Abstract
In the investigation reported here, intensity of blue fluorescence or coloration associated with human lens protein of nuclear cataract has been compared with that in the one of normal human. Blue fluorescence as well as coloration associated with proteins of aged normal lens and of nuclear cataractous lens appears to be localized in the nucleus which contains more water-insoluble protein than the cortex. In cortex and nucleus of normal lens, and in cortex of the cataractous lens, the blue fluorescence intensity of the lens protein seems to elevate linearly with an increase of percent urea-soluble protein, accompanied by a decrease of percent water-soluble protein. In nucleus of the cataractous lens, however, the fluorescence intensity tends to decrease significantly with an increase of percent urea-insoluble protein, mostly accompanied by a decrease of percent urea-soluble protein. Coloration of the lens protein tends to become deeper as human lens protein becomes insoluble. Particularly, in nucleus of the cataractous lens which contains urea-insoluble protein at a high concentration, the coloration seems to increase sharply as the content of urea-insoluble protein goes up. These results suggest the possibility that changes in the blue fluorescence intensity and coloration of human lens protein during aging of normal lens and development of nuclear cataract may be related to aggregation of the lens protein.