Palmitic acid-1-C14 oxidation by hemidiaphragms was measured in tissues from fed and starved normal and alloxanized rats. Muscle from normal rats starved for 3 days or longer showed an enhanced conversion of added palmitate to C14O2, while fasting for 1 or 2 days had little effect on fatty acid degradation by diaphragms from normal rats. Tissues from fed or starved alloxan diabetic animals had an augmented oxidation of labeled palmitate. The addition of glucose to the medium spared fatty acid oxidation by diaphragms from starved or diabetic rats but did not influence palmitate degradation by tissues from normal fed rats. The presence of insulin increased the glucose sparing action on long-chain fatty acid oxidation but was without effect on palmitate oxidation in the absence of added glucose. The conversion of C14-octanoic acid to C14O2 by muscle was not influenced by previous starvation nor by addition of glucose to the medium. Glucose-U-C14 and glucose-1-C14 conversion to C14O2 and glycogen were essentially the same in diaphragms from fed and starved animals.
- Copyright © 1960 by American Physiological Society