Abstract: To investigate the protective effects of gypenosides(GP) against glutamate-induced oxidative injury to the hippocampus of rats. Methods60 Wistar rats were randomly divided into 5 groups: the sham-operation group, the glutamate-induced injury group, the GP low (200mg/kg), medium(400mg/kg) and high (800mg/kg) dose groups. Intra-gastric administration of GP was used for 10d. 2h after injection with glutamate through the lateral ventricle, the homogenate of the hippocampus was collected and the MDA, SOD, GSH-Px activity and the hydroxyl radical generation capacity were determined. Results: The MDA concentration and hydroxyl radical generation capacity were significantly increased(P＜0.05), however activities of SOD and GSH-Px were significantly decreased (P＜0.01)in the glutamate-induced injury group compared with the sham-operation group. Also, the MDA concentration and hydroxyl radical generation capacity were significantly decreased in the GP groups compared with the glutamate-induced injury group (P＜0.01), and activities of SOD and GSH-Px were significantly increased (P＜0.01) by GP treatments, and 400mg/kg GP had the most effective action. ConclusionThe protective effects of GP against Glu-mediated nerve injury may be mediated by increasing the activity of antioxidant enzymes and inhibiting the hydroxyl radical production.

Key words: Gypenosides, Glutamate, Oxidative neurotoxicity