Increased synthesis of glycosaminoglycans of the cornea during fasting and refeeding in rats.

The effect of a 48 hour fast on sulfate incorporation of corneal mucopolysaccharides was investigated in the rat. After fasting for 24 hours, experimental and control rats were injected intraperitoneally with 35S-sulfate. After fasting an additional 24 hours, the rats were sacrificed and incorporation of the label into the acid mucopolysaccharide fraction of the cornea was determined. Incorporation of the label into the acid mucopolysaccharide fraction was significantly increased in the fasted rat cornea. Increased synthesis of corneal sulfated mucopolysaccharides during fasting in the rat contrasts with the well known decreased synthesis in cartilage under the same conditions. These findings suggest that corneal acid mucopolysaccharide synthesis is selectively preserved and/or increased during fasting.