Fat metabolism in three forms of experimental obesity; fatty acid turnover.

NLY 0 two studies on fatty acid turnover in experimental obesity could be found in the literature. In 1943 Salcedo and Stetten (I) determined the rate of lipolysis in yellow congenitally obese mice (CHS silver) using deuterium as their tracer. They used four female mice, followed them for an experimental period of only 9 days, and used as control values the results of Schoenheimer and Rittenberg (2) obtained with a different strain of mice. The exact half-life of fatty acids and daily amount of fatty acid oxidized could not be determined under these conditions. The authors concluded that, in the obese mice, fatty acid half-life time is much longer than in normal mice and that the obese mice probably burn less than normal quantities of depot fatty acids daily. In 1950, Mankin et al. (3) measured turnover of body fat in hypothalamic injury also with the aid of deuterium as a tracer. Only five animals were used, the rats being killed one by one over a span of 24 days. The rats used in this experiment had been operated on 3 months previously and their fat depots were of such size that it was difficult to measure over a period of’24 days the change in isotope concentration. It appeared, however, that the amount of fat mobilized daily by the hypothalamic animals was less than that previously reported for normal rats (4).