CHRONIC DIETARY N-3 POLYUNSATURATED FATTY-ACIDS DEFICIENCY AFFECTS THE FATTY-ACID COMPOSITION OF PLASMENYLETHANOLAMINE AND PHOSPHATIDYLETHANOLAMINE DIFFERENTLY IN RAT FRONTAL-CORTEX, STRIATUM, AND CEREBELLUM

As chronic consumption of a diet devoid of n-3 fatty acid induced modi fication of neurotransmission pathways in the frontal cortex of rats, plasmalogen alteration could occur in this area. Because of the propen sity to facilitate membrane fusion, plasmenylethanolamine (PmE), a maj or plasmalogen of brain, may be involved in synaptic transmission. Fem ale rats were fed diet containing peanut oil [(n-3)-deficient diet] th rough two generations, Two weeks before mating, half of the female rat s of the second generation received a diet containing peanut oil and r apeseed oil (control group). The distribution and acyl composition of major phospholipids, phosphatidylethanolamine and PmE, were measured i n the frontal cortex, striatum, and cerebellum of the male progeny of the two groups at 60 d of age. The n-3 polyunsaturated fatty acid (PUF A) deficiency had no effect on the distribution of phospholipids in al l brain regions but affected their acyl composition differently. The l evel of 22:6n-3 was significantly lower and compensated for by higher levels of n-6 fatty acids in all regions and phospholipids studied. Ho wever, docosahexaenoic acid, being more concentrated in the PmE of fro ntal cortex, is also more decreased in the n-3-deficient rats compared to the striatum. By contrast, striatum PmE has retained more 22:6n-3 than PmE of the other regions. In addition, the increase of n-6 PUFA w as significantly lower in frontal cortex PmE compared to the striatum and cerebellum PmE. In association with altered neurotransmission obse rved in frontal cortex of n-3-deficient rats, our results suggest that frontal cortex PmE might be more affected in chronically alpha-linole nic-deficient rats. However, by retaining 22:6n-3, striatum PmE could be most resilient.