l-S·R-daurisoline protects cultured hippocampal neurons against glutamate neurotoxicity by reducing nitric oxide production

l S·R daurisoline protects cultured hippocampal neurons against glutamate neurotoxicity by reducing nitric oxide production 1

目的：探讨ｌＳ·Ｒ蝙蝠葛苏林碱（ＤＳ）保护神经元的作用机制．方法：原代培养大鼠海马神经细胞，用台盼蓝染色和ＭＴＴ法检测神经细胞损伤，以去内皮的大鼠胸主动脉作为分析ＮＯ含量的生物检测器．结果：ＤＳ００１－１０μｍｏｌ·Ｌ－１剂量依赖性地抑制谷氨酸（Ｇｌｕ）神经毒性，ＩＣ５０为２８μｍｏｌ·Ｌ－１（９５％可信限为１２－５９μｍｏｌ·Ｌ－１），ＤＳ１０μｍｏｌ·Ｌ－１能够抑制Ｇｌｕ引起的主动脉条舒张，但对亚硝基铁氰化钠（ＳＮＰ）的动脉条舒张和神经毒性无明显的影响．表明ＤＳ不能直接对抗ＮＯ的毒性，但能抑制Ｇｌｕ刺激ＮＯ的产生．结论：ＤＳ对抗Ｇｌｕ引起的神经毒性的作用与抑制Ｇｌｕ刺激ＮＯ的合成有关．

AIM: To explore mechanisms of l S·R dau￣risoline (DS) mediated protection of cultured hippocampal neurons from sodium glutamate (Glu) cytotoxicity. METHODS: Cultured neurons obtained from rat hippocampus were used to examine the protective effect of DS against Glu neurotoxicity. Cell viability was estimated using trypan blue dye exclusion method and [3 (4,5 dimethylthiazol 2 yl) 2,5 diphenyl￣tetrazo￣lium bro￣mide] (MTT) assay. Release of nitric oxide (NO) from the hippocampus was assayed using rat thoracic aorta in vitro . RESULTS: DS 0 01-10 μmol·L -1 concentration dependently inhibited Glu cytotoxicity and increased cell viability with 50 % prevention of cell death 2 8 μmol·L -1 (95 % confidence limit 1 2-5 9 μmol·L -1 ). This protection was mostly attenu￣ated by L arginine (Arg) 1 mmol·L -1 . DS 0 01-10 μmol·L -1 did not prevent sodium nitropusside (SNP) 500 μmol·L -1 induced cytotoxicity. DS 10 μmol·L -1 blocked Glu elicited relaxation of the endothelium denued rat aortic rings contracted by norepinephrine (NE) 10 μmol·L -1 in the presence of hippocampal tissue, but did not affect that induced by SNP. This indicated that DS inhibited Glu triggered NO generation but did not prevent the effects of NO. CONCLUSION: DS prevented neurons from Glu neurotoxicity by inhibiting Glu trigged NO generation.