Intraperitoneal injection of 1-oleoyl-2-docosahexaenoyl phosphatidylcholine enhances discriminatory shock avoidance learning in rats.

Effects of injection of 1-oleoyl-2-docosahexaenoyl-sn-glycero-3-phosphorylcholine (ODHPC) on learning ability were investigated in rats using discriminatory shock avoidance learning task. When ODHPC (2 mumol) was intraperitonealy administered 5 min before the beginning of the first trial of learning task from the second to fifth sessions, avoiding rates of the ODHPC-injected group were significantly higher than those of the control group. However, any injection of ODHPC derivatives, such as 1-oleoyl-2-docosahexaenoyl-diacylglycerol, 1,2-dioleoyl-sn-glycero-3-phosphorylcholine, glycerophosphorylcholine, docosahexaenoate, oleate and choline chloride, did not affect learning. These results suggest that intraperitoneal ODHPC injection enhances learning ability by its specific conformation.