On the flux of lipid metabolism in diabetic animals

The influence of diabetes on the balance of lipid metabolism has been studied by measuring the simultaneous incorporation in vivo of 3H- and 14C-labelled glycerol into all the major tissues and lipid classes of diabetic mice. The induction of the diabetic condition caused significant alterations in the relative utilization of these labels, with double isotope ratios (3H/14C) being increased in the total lipid fractions of all tissues, but most extensively in muscle and adipose tissue. A degree of individuality was evident in relation to the response of tissue phospholipids, particularly in regard to the incorporation of tritium label into phosphatidyl choline fractions. These data establish that diabetes causes widespread and major perturbations of lipid metabolism in these animals, and indicate the detailed nature of the responses in relation to individual tissues and lipid classes. The implications of these alterations have been discussed with respect to tissue-specific and whole body aspects of the regulation of lipid metabolism.