EFFECTS OF DIETARY ALPHA-LINOLENIC ACID DEFICIENCY ON NEUROMUSCULAR AND COGNITIVE FUNCTIONS IN MICE

Mice were fed a diet deficient in alpha-linolenic acid [18 : 3 (n-3)] or a control diet and the effect of this deficiency was assessed by behavioral and pharmacological measurements. Three weeks before mating female mice were fed a diet containing either peanut oil poor in alpha-linolenic acid (n-3)(-) or peanut + rapeseed oil rich in alpha-linolenic acid (n-3)(+) = controls. Pups, aged 47 to 61 days, fed the same diet as their dams, were used for behavioral experiments. Muscular function and neuromuscular coordination assessed by the traction test, the elevated rotarod test and swimming endurance were unchanged by the (n-3)(-) deficiency. The level of anxiety assesed by the elevated plus-maze (anxiety protocol), the light-dark transition and the neophobia tests did not differ between (n-3)(-) and control (n-3)(+) mice. Defensive behavior was not changed by the diet. The pentobarbital-induced loss of the righting reflex had the same duration in males, females, and controls as in (n-3) deficient mice; the latency to pentobarbital-induced loss of the righting reflex was significantly shorter in females than in males but did not differ according to the diet. Mice fed the (n-3)(-) deficient diet showed less efficient learning in the elevated plus-maze (learning protocol) and poorer understanding of the situation (or less motivation to escape) in the low rotarod test than mice fed the control (n-3)(+) diet.