[Relationship between polyunsaturated fatty acid (PUFA) and learning ability in the brain of rat fetus and newborn]

We prepared rat newborns deficient in omega 3-polyunsaturated fatty acid (SA group) and studied the relationship between the fatty acid composition of the brain and the learning ability. DHA in the brain was decreased and the conditioned avoidance rate was lower in the SA than in the control group (SO group). In the SAO-1 group in which PUFA deficient diet was changed to the control diet on weaning (21 days after birth) and the SAO-2 group in which the diet PUFA deficient diet was changed to the control diet at the start of the Shuttle Box (60 days after birth), the conditioned avoidance rate increased later than in the SO group. After completion of the experiment the levels of, DHA, C22:5 omega 6 in the SAO-1 and SAO-2 groups recovered to the level of the SO group. Accordingly, it is suggested that the fatty acid composition of the brain is affected by the diet and that the learning ability is altered in parallel with the composition of the DHA. These findings confirm the importance of DHA as a constituent element of the brain.