PREVIOUS DIET AND THE APPARENT UTILIZATION OF FAT IN THE ABSENCE OF THE LIVER

Abstract

Adult [male] rats, force-fed a high fat diet for 3-6 wks., and then fasted 24-30 hrs., exhibited a much slower fall in blood sugar, and survived twice as long as similar animals previously maintained on a high carbohydrate diet; they did not exhibit convulsions or a blood glucose level of practically zero at death as did the carbohydrate-fed animals. Fasting O2 consumption and the rate of decline in O2 utilization after evisceration were similar in both groups and renal glyco-gen and blood acetone bodies were insignificant in all animals 5 hrs. after evisceration. Protein metabolism, as indicated by the rate of rise of blood N.P.N., was unaffected by previous diet. In animals maintained on a particular diet for a period of time, the foodstuff predominantly burned by the extra-hepatic tissues during the early stages of fasting corresponds to the major constituent of the previous diet, whether this be fat or carbohydrate.