Histopathological study of congenitally diabetic yellow KK mouse lens.

Lenses of Yellow KK mice with marked obesity and diabetic symptoms were examined by light and electron microscopy. At 2 months of age, the entire lens appeared normal. At 4 months, however, epithelial cells sometimes had become necrotic and showed intranuclear inclusions. At 6 months, the anterior cortical fibers were swollen. At 8 months, the number of intranuclear inclusions of the epithelial cells had increased, and the posterior cortex contained densely stained cells among the fibers, with swollen cytoplasm. At 10 months, these cells had become atrophic. At 12 months, the lens cells in the posterior sutural area showed marked swelling, and the suture was almost separated. This animal model showed a slow progressive cataract in the superficial cortical zone which is similar to the diabetic cataract in human eyes.