Metabolic Characteristics of the Carbohydrate-sensitive BHE Strain of Rats

Abstract

The metabolic responses to variations in kind and amount of dietary carbohydrate were investigated in young and mature male BHE rats. Kind of carbohydrate influenced weight gain, serum cholesterol levels, and the activities in the fasting state of glucose-6-phosphate dehydrogenase and malic enzyme. The age at which the pre-β-lipoprotein band appeared in the fasting sera appeared to be influenced by the carbohydrate composition of the diet. In 100-day-old rats an increased level of carbohydrate intake also increased carcass lipid. In the mature rats, the higher carbohydrate intake also resulted in greater liver lipid levels. The older animals had higher levels of serum cholesterol than the young animals fed the same diets. Histological evaluation of the kidneys and hearts of the older animals revealed the presence of hydronephrosis in all of the animals fed the 65% carbohydrate diet and in most of the animals fed the 45% carbohydrate diet. Myocardial degeneration was common to all animals examined. Arteriosclerosis of the coronary vessels was also observed in 20% of the animals fed the 45% carbohydrate diet and in 40% of the animals fed the 65% carbohydrate diet. The results of these studies indicate that the BHE strain is apparently predisposed to carbohydrate-induced hyperlipemia and thus could serve as an animal model for the investigation of the interrelationships between carbohydrate and lipid metabolism.