Estevez A G, Stutzmann J M, Barbeito L
Instituto C. Estable, Montevideo, Uruguay.
Eur J Pharmacol. 1995 Jun 23;280(1):47-53. doi: 10.1016/0014-2999(95)00186-o.
Excitatory amino acid-mediated neurotoxicity was investigated in motoneuron-enriched cultures from fetal rats at 12-14 days of gestation. The cultures were mainly composed of differentiated motoneurons identified by choline acetyl transferase and calcitonin gene-related peptide (CGRP) immunoreactivity. Addition of glutamate (600 microM) to the conditioned medium induced no acute neuronal swelling. However, it was followed by a widespread neuronal degeneration over the next 24 h, accounting for 77% of the total cell number. Glutamate toxicity was dose dependent, with an EC50 around 300 microM. Treatment for 24 h with the agonists, N-methyl-D-aspartate (NMDA, 100 microM), kainate (500 microM) or RS-alpha-amino-3-hydroxy-5-methyl-4-isoxalopropionate (AMPA, 10 microM), also induced a significant cell loss. Riluzole (2 amino 6-trifluoromethoxybenzothiazole), a compound known to interfere with glutamatergic transmission pre- and postsynaptically, significantly reduced glutamate and NMDA neurotoxicity in a dose-dependent manner. These results suggest that a prolonged activation of one or more subtypes of ionotropic excitatory amino acid receptors can lead to motoneuron degeneration in vitro, and provide direct experimental evidence supporting the neuroprotective effect of riluzole in cultured motoneurons.
在妊娠12 - 14天的胎鼠富含运动神经元的培养物中研究了兴奋性氨基酸介导的神经毒性。这些培养物主要由通过胆碱乙酰转移酶和降钙素基因相关肽（CGRP）免疫反应性鉴定的分化运动神经元组成。向条件培养基中添加谷氨酸（600微摩尔）未引起急性神经元肿胀。然而，在接下来的24小时内随后出现广泛的神经元变性，占总细胞数的77%。谷氨酸毒性呈剂量依赖性，半数有效浓度（EC50）约为300微摩尔。用激动剂N - 甲基 - D - 天冬氨酸（NMDA，100微摩尔）、海人藻酸（500微摩尔）或RS - α - 氨基 - 3 - 羟基 - 5 - 甲基 - 4 - 异恶唑丙酸（AMPA，10微摩尔）处理24小时也诱导了显著的细胞损失。利鲁唑（2 - 氨基 - 6 - 三氟甲氧基苯并噻唑）是一种已知能在突触前和突触后干扰谷氨酸能传递的化合物，以剂量依赖性方式显著降低谷氨酸和NMDA的神经毒性。这些结果表明，离子型兴奋性氨基酸受体的一种或多种亚型的长期激活可导致体外运动神经元变性，并提供了支持利鲁唑对培养的运动神经元具有神经保护作用的直接实验证据。
