【作者】 王怀立；

【导师】 金润铭；

【作者基本信息】 华中科技大学 ， 儿科学， 2008， 博士

【摘要】 第一部分脂多糖致幼年大鼠感染性脑损伤模型的建立目的:探讨一种新的模型制作方法—通过颈外动脉注射脂多糖建立幼年大鼠感染性脑损伤模型。方法:160只大鼠颈外动脉注射LPS及NS,至相应时间点处死,制备脑组织标本。检测脑组织的伊文思蓝(EB)含量,NSE、GFAP蛋白的表达量,确定大鼠感染性脑损伤模型的成功建立。结果:LPS组脑组织病理形态学改变明显,脑组织EB含量,NES、GFAP蛋白表达量均较NS组高(P＜0.01)。结论:经幼年大鼠颈外动脉注射LPS可以成功建立起稳定、可靠的感染性脑损伤实验动物模型。第二部分脂多糖诱导的幼年大鼠神经细胞凋亡及凋亡诱导因子的表达目的:研究脂多糖诱导的幼年大鼠脑损伤过程中神经细胞凋亡及凋亡诱导因子(AIF)的表达情况。方法:免疫组织化学技术检测脑组织的AIF表达情况,TUNEL法检测神经细胞凋亡数。结果:与NS对照组相比,LPS组脑组织AIF蛋白表达及神经细胞凋亡增多,差异有统计学意义(P＜0.01)。结论:凋亡参与了LPS致脑损伤的发生发展过程。AIF表达增加可能是导致神经细胞凋亡的原因之一。第三部分肝细胞生长因子对脂多糖致幼年大鼠感染性脑损伤的保护作用目的:探讨肝细胞生长因子(HGF)对脂多糖致幼年大鼠感染性脑损伤的保护作用。方法:经大鼠颈外动脉注射LPS后即刻注射HGF,观察脑组织EB含量、GFAP、NSE、AIF蛋白表达量,以及神经细胞凋亡数。结果:HGF组各时间点脑组织EB含量、NSE、GFAP、AIF蛋白表达水平低于LPS组(P＜0.01)。结论:早期应用肝细胞生长因子对LPS致幼年大鼠脑损伤具有保护作用。第四部分褪黑素在LPS致幼年大鼠脑损伤中的保护作用目的:探讨褪黑素在LPS致脑损伤中的保护作用。方法:应用LPS经大鼠颈外动脉注射,分别提前及同时腹腔注射MT,观察脑组织EB含量、GFAP、NSE、AIF蛋白表达量,以及神经细胞凋亡数。结果:MT保护组24h、48h时间点脑组织EB含量、NSE、AIF、GFAP蛋白及凋亡表达变化均低于LPS组(P＜0.05),提前组和0小时组相比无统计学意义(P＞0.05)。结论:MT对LPS致幼年大鼠脑损伤具有保护作用,可能与其降低凋亡诱导因子AIF的表达,减少神经细胞凋亡有关,与抗生素同时应用即可起到保护作用。更多还原

【Abstract】 PartⅠ:Establishment of infectious brain injury model of rats induced by LPSObjective:To explore a new kind of methods of establishing brain injury model of rats induced by LPS—injecting LPS through external carotid.Methods:160 rats were injected LPS or NS respectively and decapitated at different time points to take brain tissue samples for use.Results:Significant change were observed in LPS groups,the levels of Brain EB content,NSE and GFAP protein were all higher in LPS groups at different time points comparing with those in corresponding NS subgroups(P＜0.01).Conclusions:By injecting LPS into infant rats’ external carotid,the infectious brain injury model could be established steadily and reliably.PartⅡ:Expression of AIF and the apoptosis of nervous cells on infectious brain injury model of rats induced by LPSObjective:To study the Expression Of AIF and the apoptosis of nervous cells on infectious brain injury model of rats induced by LPS.Methods:the expressing levels of AIF protein were detected by immunohistochemistry technology and the apoptosis of neural cell was measured by TUNEL technology after the injury brain model were established.Results:The expression levels of AIF protein and the apoptosis of neural cells in LPS group were all higher than that of NS groups(P＜0.05).Conclusion:Up-regulating expression of AIF protein and the apoptosis of neural cell indicated that apoptosis might play important roles in brain metabolic homeostasis associated with the pathophysiology of brain injury induced by LPS injection.PartⅢ:Protection of HGF in the infectious brain injury model of rats induced by LPSObjective:To investigate the Protection of HGF in the infectious brain injury model of rats induced by LPS.Methods:The infectious brain injury model were established by giving LPS to the rats,at the same time HGF was given by the same methods to observe the expressing of GFAP,NSE,AIF protein,EB content and the apoptosis number of neuron to study the action of HGF in such model.Results:The levels of NSE,AIF protein,EB content and the apoptosis number of neuron were all lower in HGF groups at different time points comparing with those in corresponding LPS subgroups(P＜0.01).Conclusion:The earlier use of HGF in brain injury induced by LPS could lighten the damage of brain.PartⅣ:Protection of MT in the infectious brain Injury model of rats induced by LPSObjective:To investigate the Protection of MT in the infectious brain injury model of rats induced by LPS.Methods:The infectious brain injury model were established by giving LPS to the rats.At the same time MT was given as the same as the method of HGF to observe the expression of GFAP,NSE,AIF protein,EB content and the apoptosis number of neuron to study the action of MT in such model.Results:In MT protective groups,Compared with LPS groups,EB content and the expression levels of NSE,GFAP, AIF protein and the apoptosis nerve cells were lower,the difference was significant(P＜0.05).But no significant difference was observed between MT advanced groups and MT 0 hour groups(P＞0.05).Conclusions:MT maybe have the protective effect to the infectious injury brain,.The possible mechanism is that MT can inhibit the expression of AIF which could be related to apoptosis of nerve ceils.更多还原