中文摘要：

目的探讨泊洛沙姆188（Poloxamer 188,P188）对体外神经元损伤引起的细胞死亡及线粒体损害可能发挥的作用机制。方法采用小鼠的原代神经元培养并建立体外神经元离心损伤模型（VCID）,在损伤后10 min加入P188,观察神经元的形态变化,MTT法与LDH法检测P188对体外神经元损伤引起细胞死亡的影响。分离线粒体亚成分,采用免疫印记法检测损伤后6 h与24 h线粒体内与胞质中CytC的表达情况,并检测P188对体外神经元损伤后caspase-3表达的影响。结果显微镜观察到：与正常组相比,损伤组在外伤后24 h出现了一些结构与形态上的改变。P188处理过的神经元在损伤后24 h,在形态特征上发生明显的恢复,与对照组的形态特征类似。MTT法与乳酸脱氢酶（LDH）法结果显示：P188能明显减轻损伤引起的神经元死亡与乳酸脱氢酶漏出率。Western blot结果显示：在损伤后6 h与24 h,P188处理后均能明显抑制损伤后线粒体成分中CytC蛋白水平的下调（P〈0.05）,及胞质成分中CytC蛋白水平的上调（P〈0.05）,提示P188能明显抑制外伤引起CytC蛋白的释放。同时,P188也能抑制外伤引起的激活型caspase-3（p20）的上调（P〈0.05）。结论 P188对体外神经元损伤引起的细胞死亡及线粒体损害具有明显的神经保护作用,这种保护作用可能与抑制线粒体膜完整性破坏和抑制凋亡的线粒体途径有关。

英文摘要：

effects on chondrial Aim To investigate neuronal injury-induced cell damage and its mechanisms neuroprotective death and mitoin vitro. Methotis In cultured primary neurons of mice, a model was produced with an in vitro centrifugal injury device （VCID）, and neurons were treated with P188 after VCID 10 min. The morphological changes of neurons were first detected visually with a light microscope. The effects of P188 on VCID-induced cell death were detected by MTY assay and Lactate dehydrogenase （LDH） assay. Isolation of mitochondria was performed, and blotting for cytochrome c in mitochondrial fraction and the cytosolic fraction was observed at 6 h and 24 h after VCID. Protein levels of caspase-3 after VCID were assessed with Western blot. Results Detected visually with a light microscope, a subpopulation of mechanically injured cells without P188 treatment exhibited some structural and morphological changes after 24 h, campared with controls. Neuronal cells treated with P188 at 24 h showed a remarkable recovery of the morphological characteristic of uninjured cells. MTT assay and LDH assay revealed that P188 treatment significantly attenuated cell death and LDH leakage in neurons induced by VCID. Western bolt analysis revealed that a reduction in protein levels of CytC in mitochondrial fraction （ P 〈 0. 05 ） and a concomitant increase in CytC levels in the cytosolic fraction （P 〈 0. 05 ） were significantly inhibited by P188 treatment at 6 h and 24 h after VCID, suggesting that treatment with P188 could significantly inhibit VCID-induced release of cytochrome C from mitochondria to cytosol. In addition, treatment with P188 significantly inhibited the VCID-induced up-regulation of truncated caspase-3 （p20） levels at6 h and24 h after VCID （P〈0.01）. Conclusion The neuroprotective effects of P188 on VCID-induced cell death and mitochondrial damage, may be related to inhibiting mitochondrial membrane permeability and mitochondria-mediated apoptotic pathway.