The effect of bilateral intrahippocampal injection of phosphatidylcholine on spatial learning in adult male rats

The previous studies have shown that lecithin (phosphatidylcholine), as an important lipid in the diet and plasma membrane has a crucial role in the release of acethylcholine and process of learning and memory. Due to the fact that hippocampus is the most important part of the brain involved in learning, The aim of this research is to study, the effect of intrahippocampal (CA1) injection of lecithin (phosphatidylcholine) on spatial learning. In so doing, 49 Adult male rats dividing in to 7 groups as fallow; test groups (1 – 4), have received 1µl of lecithin dissolved in the physiological salin at concentration of (0.5, 1, 2, 4 µg / µl) 4 days sequentially, 90 minutes, before training. Group 5 received, 1µl of physiological salin, the groups 6 and 7 were respectively sham operate and control (intact). Data analysis showed that lecithin at concentration of 4 µg /µl improved spatial learning in Morris Water Maze (p< 0/05). It seems that lecithin improves spatial learning via enhancing choline and acetylcholine levels in hippocampus and increasing of fluidity of plasma membrane.