The diabetic heart: a porcine model evaluated with positron emission tomography using 1-11C-palmitate and...

The potential value of positron emission tomography (PET) in evaluating the myocardial energy metabolism was studied in two previously healthy mini-pigs before, during and after the induction of non-insulin dependent diabetes with alloxan. The distribution and kinetics of radioactivity derived from trace amounts of 11C-pyruvate and 1-11C-palmitate were followed in different sections of the myocardium. The early distribution of both tracers was similar even after the development of diabetes. The elimination of 11C-pyruvate derived radioactivity was slower in the diabetic heart. The rate of beta-oxidation was also decreased as suggested by the elimination curve of 11C-palmitate and the incorporation of 11C-palmitate into the triglyceride and phospholipid pool of the myocardium was increased in the diabetic animals. The results are consistent with previous observations using other techniques. Positron emission tomography offers the opportunity to characterize regional tissue metabolism quantitatively in vivo. This method may become a powerful tool in studying myocardial metabolism and the metabolic basis for the cardiac dysfunction in diabetes mellitus.