[Mode of fatty acid synthesis in rat liver mitochondria (author's transl)].

In order to clarify the mode of fatty acid synthesis in rat liver mitochondria, metabolism of labeled fatty acid was examined after portal and intraperitoneal administration of several labeled fatty acids. 1) After portal administration of palmitic acid-1-14C, alpha, beta-mono-unsaturated fatty acid (C18:1) was synthesized as a result of chain elongation by addition of endogenous C2 compound 20 min. after injection. 2) Similarly, after lauric acid-1-14C injection, myristic acid (C14) and palmitic acid (C16) were found 20 min. after injection and even C18:2 was detected 30 min. after injection. 3) Following intraperitoneal administration of lauric acid-1-14C, the appearance of palmitic acid (C16) was confirmed in inner mitochondrial membranes 60 min. after injection. From the analysis of intramolecular distribution of labeled carbon, it is surmised that lauric acid is first decomposed into C2 fragments which then are used for the chain elongation.