Ultrastructural study of selenite-induced nuclear cataracts.

The formation of the selenite-induced cataract was investigated by examining the ultrastructure of the cataract with transmission electron microscopy (TEM). A lacy, or honeycomb, appearance of the nuclear cataract seen by light microscopy was resolved by TEM to be due to the aggregation or precipitation of cytoplasmic material. Despite severe intracellular changes the fibers retained their close apposition to one another. These results are consistent with the hypothesis that a major lesion in selenite-induced nuclear cataracts is the formation of insoluble cytoplasmic aggregates.