Formation of Polyols by the Lens of the Rat with ‘Sugar’ Cataract

Abstract

CATARACT (opacity) of the lens inevitably develops in young rats fed xylose or galactose1, or in young diabetic rats if the blood glucose is maintained at a level above 2.5 mgm./ml. blood2. These three forms of cataract which resemble each other closely in clinical and histological appearance, are known as ‘sugar’ cataracts because in all cases there is a raised level of monosaccharides in the blood. The early metabolic changes within the lens, which lead to gradual loss of transparency, are unknown. It was decided to examine the carbohydrates and their derivatives in normal and cataractous lenses to see if changes occurred in ‘sugar’ cataract, and if so whether there was any similarity in this respect between the three forms of cataract.