SUBCELLULAR-DISTRIBUTION OF [1-C-14]PALMITATE AND [1-C-14]OLEATE INCORPORATED INTO LIPIDS IN PERFUSED RAT-HEART - COMPARISON UNDER ISOTHERMAL AND HYPOTHERMIC CONDITIONS

Isolated rat hearts have been perfused with [1-14C]palmitate and [1-14C]oleate for varying periods of time followed by unlabelled perfusion for varying periods of time. The degree of incorporation of the label into the lipids of mitochondrial, microsomal and cytoplasmic fractions has been studied. At the same time lipid separation by thin layer chromatography has given an indication of rates and location of esterification to triglyceride. The results have been analyzed in the light of the previously defined limitations of the methods of cell fractionation. The accumulation of lipid radioactivity reached a plateau in the cytoplasmic and mitochondrial fractions at 60 s. Radioactivity continued to increase in the microsomal fraction due to the progressive formation of triglyceride. The formation of triglyceride was dependent on temperature. The uptake of palmitate into lipid was greater than that of oleate. © 1978.