Sugar and Sugar Alcohol Levels in the Aging Rat Lens.

Fructose and sorbitol accumulate in the aging rat lens, the levels rising from values of 7 and 17 mg. per 100 Gin. wet lens weight, respectively, in weanlings, to 27 and 34 mg. per 100 Gm. in 200-day-old animals. The formation of fructose and sorbitol from glucose via the sorbitol pathway apparently decreases with age. Penetration of the lens in vitro by fructose-U-C-14 decreases with age. Furthermore, since the levels of glucose in the lens and aqueous humor and of fructose in the aqueous humor do not increase with age, the increased levels of fructose and sorbitol in older lenses must be a consequence of the failure of fructose to escape as readily from older lenses as from younger lenses.