Male Sprague-Dawley rats were fed diets containing 20% (w/w) soya-bean oil, high-erucic acid rapeseed oil or low-erucic acid rapeseed oil for 0, 12 or 23 days. The type of fat present in the diet had no effect on the total phospholipid content of heart mitochondria (micrograms/mg of protein) but did influence the phospholipid class distribution. Rats fed high-erucic acid rapeseed oil for 12 or 23 days had significantly higher mitochondrial phosphatidylcholine content than rats fed soya-bean oil. Low-erucic acid rapeseed oil resulted in elevation of cardiac mitochondrial cardiolipin content after dietary treatment for 12 days. The results demonstrate in vivo that diet is a significant determinant of the phospholipid class content of subcellular membranes.
