去铁敏对体外培养的大鼠海马神经元谷氨酸毒性的保护作用

目的 探讨去铁敏对体外培养的海马神经元谷氨酸损伤的保护作用及可能机制.方法 建立体外培养的大鼠海马神经元谷氨酸毒性模型.细胞分为去铁敏组、对照组.采用形态学观察、Hoechst 33342染色、乳酸脱氢酶(LDH)检测评价细胞损伤情况.生化法检测羟自由基、丙二醛变化.用显微荧光测量技术监测神经元内钙信号的动态变化.结果 去铁敏组较对照组神经元形态保持良好.去铁敏组及对照组细胞核固缩率分别为14%±6%和58%±6%(t=8.98,P＜0.01),LDH分别为(36.42±8.99)U/L和(68.06±11.26)U/L(t=3.25,P＜0.05),羟自由基分别为(34.21±4.23)U/L和(47.06±8.79)U/L(t=3.11,P＜0.05),丙二醛分别为(12.26±2.78)nmol/mg和(28.86±5.19)nmol/mg(t=4.88,P＜0.01).结论 去铁敏能减轻谷氨酸导致的神经元损伤,其可能的机制与去铁敏减少谷氨酸导致的神经元内钙浓度的升高及自由基水平有关.

Protective effect of deferroxamine on glutamate induced neurotoxicity in cultured rat hippocampal neurons

Objective To investigate the protectve effects and underlying mechanisms of deferroxamine on glutamate-induced injury in cultured hippocampal neurons.Methods Primarily cultured hippocampal neurons from fetal rat were used in a model of glutamate induced neurotoxicity.There were two experimental groups.Neurons were pretreated with deferroxamine before glutamate in the deferroxamine group, and neurons were treated with glutamate only in the control group.The morphological change was examined under microscope.Hoechst 33342 DNA staining method was used to study the ratio of condensed nuclei.The levels of lactate dehydrogenase (LDH), malonaldehyde (MDA) and hydroxyl radical were determined using biochemistry.The change in calcium signal was detected using microfluorescent technique.Results The neurons pretreated by deferroxamine had intact morphology with the ratio of condensed nuclei at 14% ± 6% compared to 58% ± 6% (t= 8.98, P ＜0.01 ) in the control group.LDH level was (36.42 ± 8.99) U/L in the deferroxamine group and was (68.06 ± 11.26) U/L in the control group ( t =3.25,P＜0.05).The respective levels of hydroxyl radical were (34.21 ±4.23) U/L and (47.06 ±8.79) U/L (t = 3.11, P ＜0.05 ).The respective levels of MDA were (12.26 ± 2.78 ) nmol/mg and (28.86±5.19) nmol/mg(t =4.88,P＜0.01).Conclusion Deferroxamine can protect neurons from glutamate induced damage.The mechanisms include an inhibition of Ca2+ overload and reduction in the levels of MDA and hydroxyl radicals.