Abstract
The influence of long-term n-3 fatty acid deficiency on the rate of protein synthesis in rat brain and liver was investigated in relation to learning behavior or a presumed survival time-shorttening factor (SSF) in rapeseed oil, using a large-dose [3H]phynylalanine (Phe) injection method. When Wister rats were made n-3 fatty acid-deficient by feeding a safflower oil (α-linolenate-deficient) diet for 2 generations, conditions under which the safflower oil group had been shown to exhibit altered learning behaviors, compared with the perilla oil group, no significant changes in the rate of protein synthesis were observed compared with the perilla oil (α-linolenate-sufficient) of rapeseed oil (α-linolenate-sufficient but SSF-containing) groups. However, the rapeseed oil group had a reduced specific raioactivity of free Phe in the cerebral cortex, compared with the safflower oil group. In contrast to the reported oservation of very long-term n-3 fatty acid deficiency inducing an almost 2-fold increase in the rate of protein synthesis in the brain, our results indicate that altered learning behavior resulting from n-3 fatty acid deficiecy in rats is not associated with any substantial changes in the rate of protein synthesis in the brain.
