Circannual variation in the fatty acid composition of high-density lipoprotein phospholipids during acclimatization in trout

Abstract

A circannual variation in the fatty acid composition of plasma and high-density lipoprotein (HDL) phospholipids occurs in rainbow trout ( Oncorhynchus mykiss) in response to seasonal alterations in environmental water temperature. The compensatory mechanisms employed in cold adaptation include a decrease in the level of saturated fatty acids and of monoenes of the oleic acid ( n − 9) family and an increase in the level of unsaturated fatty acids of the linolenic acid ( n − 3) family, especially in docosahexaenoic acid (22:6( n − 3)). The present study demonstrates that in trout, a poikilothermic vertebrate, the weight percentage of 22:6( n − 3) in HDL phospholipids is inversely correlated ( r = − 0.88, P < 0.0001) with water temperature.