母体IgG对NMDA诱导的其幼鼠海马神经元损伤的保护作用的研究

目的研究母体免疫球蛋白G（immunoglobulin G,IgG）对N甲基D天冬氨酸（N-methyl-D-aspartate,NMDA）诱导的其幼鼠海马神经元损伤的作用及机制。方法通过体外幼鼠海马神经元原代培养,观察海马神经元在NMDA神经毒性作用下的变化,以及给予不同浓度的母体IgG后的影响。通过测定神经元漏出的乳酸脱氢酶（lactic dehydrogenase,LDH）活力,观察神经元损伤情况,用锥虫蓝染色观察细胞死亡率。结果体外神经毒性损伤后,培养神经元漏出的LDH较NMDA处理前和正常对照组高（P〈0．01）;给予不同浓度的母体IgG（分别为10mg／L、100mg／L）后,LDH漏出较NMDA组低（均P〈0．01）,而且较大剂量比小剂量的保护作用更为显著（P〈0．05）。锥虫蓝染色显示NMDA组神经元死亡率较NMDA处理前和正常对照组高（P〈0．01）;给予不同浓度的母体IgG（分别为10mg／L、100mg／L）,死亡率均比NMDA组低（P〈0．05、0．01）,而且较大剂量比小剂量的保护作用更强（P〈0．05）。结论体外幼鼠海马神经元原代培养结果表明,50μmol／L NMDA可诱导幼鼠海马神经元损伤,母体IgG对NMDA的神经毒性有保护性作用,而且有剂量依赖关系。

Protective effect of maternal immunoglobulin G against NMDA-induced neurotoxicity on hippocampus neurons

OBJECTIVE: To investigate possible protective effect of maternal immunoglobulin G (IgG) against N-methyl-D-aspartate-mediated neurotoxicity on primary-cultured rat hippocampal neurons and the mechanism of the effect. METHODS: An in vitro system had been developed for the study of hippocampal neurons. Intracellular lactic dehydrogenase (LDH) release was used as a marker to measure the rates of neuronal damage. The cells were stained with Trypan blue to measure the rate of neuronal death. RESULTS: N-methyl-D-aspartate (NMDA) at a concentration of 50 micromol/L resulted in increased release of LDH and the cell mortality (P < 0.01, respectively). Maternal IgG of different concentration (10 mg/L, 100 mg/L) inhibited NMDA-induced intracellular LDH release (P < 0.01, respectively) and cell mortality (P < 0.05, 0.01, respectively), and larger dose had stronger effect (P < 0.05). CONCLUSIONS: Maternal IgG had protective effect on primary-cultured rat hippocampal neurons injured by NMDA and the effect was dose-dependent.