title: N-3 fatty acid deficiency induced by a modified artificial rearing method leads to poorer performance in spatial learning tasks.
abstract: Docosahexaenoic acid (DHA) is a major structural component of the nervous system, and depletion may lead to losses in neural function. Our objective was to demonstrate a deficit in spatial task performance in rats with low brain DHA due to a low n-3 fatty acid intake using a first-generational artificial rearing technique. Newborn rat pups were separated on d 2 and assigned to two artificial rearing groups or a dam-reared control group. Pups were hand fed artificial milk via custom-designed nursing bottles containing either 0.02% (n-3 Def) or 3.1% (n-3 Adq) of total fatty acids as LNA. At d 21, rats were weaned to either n-3 Def or n-3 Adq pelleted diets and several behavioral tasks were evaluated at 9 wk of age. Brain DHA was lower (58% and 61%, p < 0.001) in n-3 Def in comparison to n-3 Adq and dam-reared rats, respectively. At adulthood, the n-3 fatty acid-deficient rats had a significantly greater moving time than the dam-reared group (p < 0.05), but there were no differences among the three groups in the elevated plus maze test. The n-3 fatty acid deficient rats exhibited a longer escape latency (p < 0.05) and poorer memory retention in the Morris water maze compared with n-3 fatty acid adequate and dam-reared rats. We concluded that artificial rearing can be used to produce n-3 fatty acid deficiency in the first generation. This deficiency was associated with significantly reduced spatial learning. Adequate brain DHA levels are required for optimal spatial learning.
authors.affiliation: Marine Environment and Bioscience, Korea Maritime University, Busan.
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Lim
authors.forename: Junji
authors.initials: J
authors.lastname: Hoshiba
authors.forename: Toru
authors.initials: T
authors.lastname: Moriguchi
authors.forename: Norman
authors.initials: N
authors.lastname: Salem
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D000831:Animals, Newborn; D016718:Arachidonic Acid / Q000378:metabolism; D001835:Body Weight; D001921:Brain / Q000378:metabolism; D004281:Docosahexaenoic Acids / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000378:metabolism* / Q000494:pharmacology; D005260:Female; D007858:Learning; D008055:Lipids / Q000737:chemistry; D018782:Maze Learning; D008568:Memory; D051381:Rats; D020318:Rats, Long-Evans; D013037:Spatial Behavior; D013997:Time Factors
chemical_list: D015525:Fatty Acids, Omega-3; D008055:Lipids; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid