Changes in rat heart phospholipid composition after rapeseed oil feeding.

The influence of long duration rapeseed oil feeding with high or low levels of erucic acid has been investigated on rat heart phospholipids. The rats treated for 20 wk with rapeseed oil containing 46.2% erucic acid showed a twofold increase in the sphingomyelin content of the heart. Treatment with primor rapeseed oil (3.7% erucic acid) for 20 wk did not modify phospholipid composition of rat heart. The fatty acid patterns of phosphatidylethanolamine and phosphatidylcholine were slightly influenced by the high erucic rapeseed oil; eicosenoic acid was incorporated preferentially into position one, but erucic acid showed a random distribution in both. After high erucic rapeseed oil feeding, 22:1 was incorporated into cardiolipin (5.6%) and sphingomyelin (10.5%). The incorporation of 22:1 into sphingomyelin was associated with an increase of the percentage of 24:1 (14.6%) and a decrease of saturated long chain fatty acid (22:0, 24:0) percentages. Primor rapeseed oil caused a slight increase of 24:1 and a decrease of 22:0 and 24:0 in rat heart sphingomyelin. As cardiolipin is localized in the inner membrane of mitochondria and sphingomyelin in plasma and microsomal membranes, the acyl-moiety alterations of both phospholipids might be correlated to the pathological lesions of rat heart after a long duration of rapeseed oil feeding.