An n-3 fatty acid deficiency impairs rat spatial learning in the Barnes maze.
In this study, the authors demonstrate that rats with n-3 fatty acid deficiency display spatial learning deficits in the Barnes circular maze. Dams were deprived of n-3 fatty acids during pregnancy and lactation, and their offspring were weaned to the same deficient diet. There was a 58% loss of brain docosahexaenoic acid (DHA) in the n-3 fatty acid-deficient rats in comparison to n-3 fatty acid-adequate rats. At 8 weeks of age, deficient rats demonstrated moderate impairment in Barnes maze performance compared with the n-3 fatty acid-adequate rats during the initial training. In the reversal learning task, the n-3 fatty acid-deficient rats showed a profound deficit in performance: They required more time to find a new position of the escape tunnel, which was accompanied by a higher number of errors and perseverations. The n-3 fatty acid-deficient rats had reduced tissue levels of dopamine in the ventral striatum and enhanced levels of the metabolite 3,4-dihydroxyphenylacetic acid in frontal cortex and hypothalamus. In summary, this study demonstrates that rats with low brain DHA have a deficit in spatial reversal learning that could be related to changes in dopamine transmission in critical brain circuits.
Fedorova
Irina
I
Laboratory of Membrane Biochemistry and Biophysics, Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism (NIAAA), Rockville, Maryland, USA. ifedorova@martek.com
Hussein
Nahed
N
Baumann
Michael H
MH
Di Martino
Carmine
C
Salem
Norman
N
D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D001923:Brain Chemistry / Q000187:drug effects; D004041:Dietary Fats / Q000008:administration & dosage*; D004281:Docosahexaenoic Acids / Q000378:metabolism; D005106:Exploratory Behavior / Q000187:drug effects / Q000502:physiology; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage* / Q000378:metabolism; D005260:Female; D018782:Maze Learning / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D020318:Rats, Long-Evans; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D013037:Spatial Behavior / Q000502:physiology*
D004041:Dietary Fats; D015525:Fatty Acids, Omega-3; D018377:Neurotransmitter Agents; D004281:Docosahexaenoic Acids