p38MAPK信号通路抑制剂对NMDA诱导的体外培养的皮层神经元损伤的保护作用及机制

目的 观察MK801及SB203580对N-甲基-D-天（门）冬氨酸（NMDA）诱导的皮层神经元损伤的影响, 探讨p38丝裂原活化蛋白激酶（p38MAPK)信号通路在神经元损伤中的作用和机制。方法 培养7d的新生SD大鼠皮层神经元随机分为对照组、NMDA损伤组、MK801干预组、SB203580干预组、联合干预组（SB203580+MK801）。MTT比色实验评价细胞生存力,乳酸脱氢酶(LDH)释放率测定细胞损伤程度，吖啶橙/溴化乙锭 (AO/EB) 双重荧光染色观察细胞凋亡形态和数目，Western blotting检测大鼠皮层神经元各组p38MAPK、BCL-2和BAX表达情况。结果 与对照组比较，NMDA损伤组神经细胞存活力降低、培养上清液中LDH含量增加、凋亡细胞增多、p38MAPK和BAX表达增加(P均＜0.01)，BCL-2表达降低(P＜0.05)；与NMDA损伤组比较，各个干预组细胞生存力提高、LDH释放率降低、凋亡减少、p38MAPK及BAX的表达减少、BCL-2表达增多(P均＜0.01)。结论 MK801，SB203580对NMDA诱导的皮质神经元损伤具有保护作用，p38MAPK通路可能参与介导MK801的保护作用，其共同机制是通过抑制p38MAPK信号通路介导的凋亡相关蛋白实现的。

Protective effects and mechanism of p38MAPK signaling pathway inhibitors on NMDA-induced primary cultured cortical neurons injury in vitro

Objective To observe the effects of MK801 and SB203580 on N-methyl-D-aspartic acid (NMDA)-induced cerebral cortical neurons injury and to explore the role of p38 mitogen-activated protein kinases(p38MAPK) signaling pathway in neurons injury and its possible mechanisms. Methods Newborn SD rat cortical neurons were cultured for 7 days, then randomly divided into the control group, NMDA injury group, MK801 intervention group, SB203580 intervention group and combined intervention group（SB203580 + MK801）． MTT assays and LDH release were employed to assess viability of primary neurons and cell membrane damage, respectively. Acridine orange/ethidium bromide (AO/EB) double fluorescent staining was used to observe morphology and cell apoptosis. Expression of p38MAPK, BCL-2 and BAX were observed respectively by Western blotting. Results Compared to the control group, NMDA injury group showed decreased cells viability(P＜0.01) and the expression of BCL-2(P＜0.05), increased leakage of LDH, the number of apoptotic cells and expression of p38MAPK and BAX(all P＜0.01). Compared to NMDA injury group, MK801 and SB203580 improved the cell viability, reduced LDH release rate and apoptosis, decreased the expressions of p38MAPK and BAX, and increased the expression of BCL-2(all P＜0.01). Conclusion MK801 and SB203580 have protective effects on NMDA-induced injury neurons, and MK801 may protect the neurons from NMDA injury through p38MAPK pathway; they can inhibit the apoptosis-related proteins which are mediated by p38MAPK signaling pathway.