Posterior subcapsular cortical cataract by inhibitor on DNA replication

2',3'-dideoxythymidine (d2T) and 1-beta-D-arabinofuranosyl-cytosine (ara C) were added to the cultured rat crystalline lens and histological changes were observed until the 7th day. With the addition of d2T, no development of cataract was observed in the gross or histological examinations. With the addition of ara C, however, anterior capsular opacity developed by the 3rd day and histological observations revealed a marked reduction in the number of anterior epithelial cells. By the 7th day, opacity of the posterior subcapsular cortex was added to the gross findings and the histological features included vesicle formation and development of Morgagni vesicles immediately below the posterior capsule vesicle formation and development of Morgagni vesicles immediately below the posterior capsule (corresponding to the area of opacity of the gross findings), total disappearance of the anterior capsular epithelial cells, and the existence of degenerated epithelial cells and bladder cells in the bow area. 1) Lack of development of cataracts in spite of the addition of d2T was interpreted to indicate that suppression of the DNA repair mechanism not participate in the etiology of a cataract. 2) Development of cataracts with addition of ara C appeared to implicate suppression of replication of the lens epithelial cells as a cause of cataracts.