绞股蓝总皂苷对谷氨酸所致大鼠海马组织损伤的保护作用

目的探讨绞股蓝总皂苷(gypenosides, GP)对大鼠侧脑室注射谷氨酸(glutamate, Glu)引起的海马组织氧化损伤的保护作用。方法将大鼠随机分为假手术组、Glu损伤组、GP低（200mg/kg）、中（400mg/kg）、高（800mg/kg）剂量组。GP组预先灌胃给药10d。大鼠经侧脑室注射Glu后2h取脑，测定各组大鼠海马组织匀浆中的丙二醛(MDA)含量、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶(GSH-Px) 活性及产生羟自由基的能力;制备海马组织切片，观察各组形态学变化。结果Glu损伤组大鼠海马组织中MDA含量和羟自由基生成能力均高于假手术组(P＜0.05)，而SOD和GSH-Px活性降低(P＜0.05)；与Glu损伤组比较，GP组MDA含量和产生羟自由基的能力降低(P＜0.01)，SOD和GSH-PX活性明显增强(P＜0.01)；HE染色显示, GP组海马神经元变性及坏死较Glu损伤组明显减少。GP 400mg/kg对Glu所致海马组织氧化损伤的保护作用最为明显。结论GP通过增强抗氧化酶活性，抑制羟自由基和脂质过氧化物生成而减轻Glu介导的氧化性神经损伤，发挥神经保护作用。

Protective effects of gypenosides against glutamate-induced hippocampus injury in rats

Objective To investigate the protective effects of gypenosides(GP) against glutamate-induced oxidative injury to the hippocampus of rats.Methods 60 Wistar rats were randomly divided into 5 groups: the sham-operation group,the glutamate-induced injury group,the GP low(200 mg/kg),medium(400 mg/kg) and high(800 mg/kg) dose groups.Intra-gastric administration of GP was used for 10 d.2 h 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 400 mg/kg GP had the most effective action.Conclusion The 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.