Abstract: AIM: To research the effects of hemp seed oil on learning and memory performances in senile mice induced by D-galactose and its mechanisms.METHODS: By using the D-galactose-induced aging mice, learning and memory performances were tested with step down, water maze and Morris water maze test, and determined the activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and content of malonaldehyde (MDA) in brain tissue, determined the content of acetylcholine (Ach) and activities of acetylcholine esterase (AchE), choline acetyltransferase (ChAT) in cerebral cortex and hippocampus; analyzed brain tissue histopathological examination simultaneously.RESULTS: Hemp seed oil (3, 6, 12 mL/kg) could significantly prolong the latency, reduce the error frequency in step down test, reduce the reaching time and error frequency in water maze test, obviously shorten the escape latency and reaching primary platform time, increase passing through primary platform frequency and resided time in Morris water maze test. It could obviously reduce the content of MDA, increase activities of T-AOC, SOD, GSH-Px in brain tissue, remarkably increase the content of Ach and activities of AchE, ChAT in cerebral cortex and hippocampus and reduce the brain tissue injury.CONCLUSION: Hemp seed oil improves the learning and memory performances of the D-galactose-induced aging mice. The mechanism may be related to increased activity of antioxidation and scavenge of free radicals, improved function of the central cholinesterase system.

Key words: Hemp seed oil, Senile, Learning and memory, Reactive oxygen species, Cholinesterase system, Mice