Comparison of ovarian and hypothalamic obesity syndromes in the female rat: Effects of diet palability on food intake and body weight.

Abstract

Both ovariectomy and hypothalamic knife cuts produced hyperphagia and obesity in adult female rats. The ovarian obesity was virtually independent of diet palatability. Ovariectomized rats became obese on quinine-adulterated diets, which completely blocked hypothalamic obesity, and they displayed little further weight gain when given a high-fat diet, which greatly potentiated hypothalamic obesity. Ovarian and hypothalamic obesity were also additive irrespective of diet condition when both surgical treatments were combined in the same animal; ovariectomy increased the food intake and body weight of knife-cut animals given the quinine or high-fat diet. Ovariectomy, hypothalamic cuts and the combined surgeries did not differentially alter the aversion to a .01% quinine solution. Ovarian obesity and hypothalamic obesity represented 2 different feeding disorders and were mediated by separate neural mechanisms. The functional nature of these disorders was discussed in light of recent body weight set point interpretations.