出版社：American Society for Biochemistry and Molecular Biology
摘要：Subcutaneous fat cells were isolated from genetically obese rats and from rats with obesity produced by hypothalamic lesions. Insulin did not augment the oxidation of fatty acids or their synthesis from glucose-1-14c or glucose-1-3H by fat cells from either group. Radioactivity from pyruvate-3-14C was incorporated into fatty acids to the same degree by fat cells from these two groups. The presence of 5 m m glucose in the incubation medium containing fat cells and pyruvate-3-14C or aspartate-3-14C stimulated the synthesis of fatty acids to a greater extent in cells of genetically obese rats. Fasting, in contrast, reduced the incorporation of radioactivity from pyruvate and glucose into fatty acids by fat cells from the genetically obese animals. In all experiments the fat cells from genetically obese rats converted more radioactivity into glyceride-glycerol relative to CO2 than did fat cells from hypothalamic obese rats. Parabiosis between one thin and one genetically obese litter mate was performed in three pairs of rats without influencing growth of either rat. Thus in the present studies fat cells from genetically obese rats showed two differences from normal fat cells: they channeled more radioactivity from pyruvate into fatty acids in the presence of glucose, and they uniformly converted more radioactivity into glyceride-glycerol.
