Changes of oligosaccharides and fatty acids in monkey hippocampus by synaptic potentiation

We measured the release of free fatty acids and structural changes of glycoprotein glycans induced by tetraethylammonium (TEA) salt in hippocampal slices of cynomolgus monkey brain. The release of free fatty acids in the hippocampal slices occurred after synaptic potentiation by TEA in a different manner from rat hippocampus. Arachidonic acid release in monkey hippocampus occurred much faster than that in rat. Several types of glycans of monkey hippocampal glycoproteins were determined depending on the duration time after TEA treatment. 5-Mannose was increased within 2 min, while polysialoglycans were increased after 5 min or later. Comparative study of glycans of monkey and rat hippocampal slices revealed the presence of relatively larger amount of sialo- and multi-anntenary glycans in rat than in monkey. These results indicate that the depolarizing stimulation of monkey hippocampal slices induced the change of glycoprotein glycan structures and release of free fatty acids in a different manner from rat hippocampus.