EFFECT OF EXCESS VITAMIN A ON ACID MUCOPOLYSACCHARIDES IN RAT LIVER

Oral administration of excess vitamin A caused a marked decrease of acid mucopolysaccharides in rat liver. This decrease was pronounced in the non-sulfated fraction of acid mucopolysaccharides, but a reduction of chondroitin sulfates A and C was also noticed with prolonged administration. An increase of hepatic hyaluronidase activity in the whole homogenate and the release of the enzyme into the soluble fraction were found with the hypervitaminotic A treatment. The mechanism which causes quantitative and qualitative changes in hepatic acid mucopolysaccharides with hypervitaminosis A is discussed in relation to the changes in hepatic hyaluronidase activity. © 1969.