银杏内酯B对谷氨酸诱导大鼠大脑皮质神经元氧化损伤的影响

【目的】探讨银杏内酯B(ginkgolide B)对谷氨酸(glutamate)引起原代培养的脑皮质神经元氧化损伤的保护作用。【方法】采用改良的方法原代培养胎鼠脑皮质神经元,用噻唑蓝(MTT)及乳酸脱氢酶法分别检测神经元的存活率和损伤情况;用硫代巴比妥酸法测定细胞脂质过氧化的程度;并同时检测了细胞内抗氧化酶的活性。【结果】银杏内酯B(10～100μmol/L)能剂量依赖性地抑制谷氨酸(0.8 mmol/L)引起的细胞存活率下降和细胞损伤,同时提高细胞内抗氧化酶活性和减轻细胞脂质过氧化。【结论】银杏内酯B可拮抗谷氨酸所致的神经细胞毒性作用,这可能与其能提高神经细胞内抗氧化酶活性和清除氧自由基有关。

Effects of Ginkgolide B on Glutamate- induced Oxidation Insult in the Cultured Cortical Neurons of Rat

[Objective ]To explore the neuroprotective effects of ginkgolide B on glutamate - induced cortical neurons cytotoxicity. [Methods ] Primary neuron culture was prepared according to slight modification of a previously reported procedure. Neuron damage was induced by 0. 8 mmol/L glutamate. The cell survival rate was monitored by lactate dehydrogenase(LDH) release and 3-(4, 5-dimethylthia zol-2-yl)- 2, 5-diphenyltetrazolium bromide (MTT) assays. The content of malondialdehyde (MDA), as the index of lipid peroxidation, was measured by a fluorometric assay. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were detected according to the kits. [Results] The cells, exposed to glutamate (0. 8 mmol/L for 12 h), showed characteristic change of damage, which could be relieved by the treatment of ginkgolide B, with survival increasing and LDH release decreasing. The falls of antioxdant enzyme activities were involved in glutamate neurotoxicity. Ginkgolide B could reverse the falls and decrease the content of MDA or the lipid peroxidation. [Conclusion] Ginkgolide B can prevent the neurons from the insults induced by glutamate. The function of ginkgolide B may be correlated with the increased activities of antioxidant enzymes and the clearance of free radicals.