Inhibitory effect of erucylcarnitine on the oxidation of palmitate by rat heart mitochondria.

In rat and some other species a diet with a high caloric per cent of rapeseed oil induces the rapid accumulation in their heart muscles of fat droplets, consisting mainly of triglycerides [ 1, 21. Macroscopically the hearts grow pale and the contractile force of the heart muscles decreases markedly after 2-3 days, The adverse effect of rapeseed oil is mainly caused by erucic acid (cis13-docosenoic acid) which constitutes 30-40% of the fatty acids in rapeseed oil [2, 31. In many countries this oil is used in small amounts for domestic consumption and as a constituent for the production of margarine [4] . The present knowledge about the effects of erutic acid stems largely from studies of the growth of rats, histopathological studies and lipid analyses of organs from animals fed on rapeseed oil [2, 5,6]. The biochemical mechanisms of the effects have been little studied. In viva studies have shown that erucic acid can be &oxidized [7] . It has recently been shown that heart mitochondria from rats which have been fed on rapeseed oil, oxidize several substrates such as cr-oxoglutarate, succinate and caprinate at a reduced rate and give low P/O ratios [8]. In the present work evidence is presented that erucic acid or some of its metabolites inhibits the oxidation of other fatty acids in the heart.