Plasma triglycerides in genetically obese rats

Abstract

Plasma triglycerides and cholesterol have been measured in rats with genetic obesity, lean littermates, and rats with obesity and hyperphagia secondary to ventromedial hypothalamic lesions. The genetically obese rats ate more than their lean littermates. Obese rats, whether genetic or hypothalamic, had comparably elevated levels of plasma triglyceride but in only the genetic obese rats was the cholesterol high. Fasting for seven days reduced the triglycerides to normal levels. When the food intake of genetic obese and hyperphagic rats was restricted to that of lean littermates (pair-feeding) the genetic obese rats had significantly higher levels of triglycerides than the other two groups. Feeding glycerol enhanced the triglyceride value comparably in the two groups. We conclude that the elevated plasma triglycerides in the genetically obese rats are related in part to the genetic basis for the obesity and not due simply to overeating.