Hypervitaminosis D and Glycosaminoglycan Metabolism in Rats Fed Normal and High Fat Cholesterol Diets

Abstract
Hypervitaminosis D for a period of 3 weeks was found to result in inereased total cholesterol, phospholipid and triglyceride levels of the serum, liver and aorta in both normal and high fat cholesterol diet-fed rats, the extent of increase being more in the latter group. Hypervitaminosis D was also found to result in decrease in the glycosaminoglycans—hyaluronic acid, heparan sulphate, chondroitin sulphates A, B and C and heparin—in the aorta of rats fed normal and high fat cholesterol diets, the decrease being more in the latter group. The lipoprotein lipase activity was found to decrease in the aorta, liver and heart of rats fed massive doses of vitamin D. DNA, RNA and soluble proteins were also found to decrease in the liver and aorta, while collagen was found to increase and elastin to decrease in the aorta. All these changes were observed to a greater extent in the high fat cholesterol diet-fed rats receiving massive doses of vitamin D, as compared to the normal diet-fed rats receiving vitamin D.