脑损伤论文：创伤性脑损伤大鼠乙酰胆碱、脑源性神经生长因子表达变化的研究

脑损伤论文：创伤性脑损伤大鼠乙酰胆碱、脑源性神经生长因子表达变化的研究 脑损伤论文:创伤性脑损伤大鼠乙酰胆碱、脑源性神经生长因子表达变化的研究 【中文摘要】建立创伤性脑损伤(traumatic brain injury，TBI )模型，探讨创伤性脑损伤大鼠乙酰胆碱(Acetylcholine,Ach)和脑源性神经生长因子(Brain-derived neurotrophic factor,BDNF)变化及其意义。方法健康雄性SD大鼠192只，体重250-300g，随机分为脑损伤组(简称TBI组，n=144只)及对照组(n=48只)。TBI组再随机化分为:轻、中、重度颅脑损伤组3组(各组48只)。各TBI组及对照组，皆随机化分为15min、0.5、1、3、6、12、24、48h各8个亚组，每亚组均为6只。参照FEENEY’S法，采用自制自由落体打击装置，对轻度、中度、重度组分别给予200g(cm、600g(cm和1000g.cm打击力致伤，制作轻度、中度、重度TBI模型。各TBI组及对照组于损伤后相应观察时间点处死，取海马、皮质等脑组织。用酶联免疫吸附ELISA法检测Ach、BDNF在不同脑组织中的含量，HE染色观察TBI中组织病理改变。结果(1)TBI中Ach与BDNF海马含量变化呈明显正相关(r_s=0.340，P<0.01), Ach与BDNF皮质含量变化亦呈正相关(r_s=0.311，P<0.01)。颅脑损伤后，脑组织Ach含量先立刻升高，随之迅速下降，降至正常水平以下;BDNF变化规律是损伤后缓慢升高，随之缓慢下降。不同程度TBI组及对照组之间Ach、BDNF脑组织总含量不相同，差异具有统计学意义(P<0.01)。TBI相同 损伤程度中不同观察时间点之间脑组织ACH、BDNF含量不同,差异具 有统计学意义(P<0.01)。(2)光镜观察显示:轻度颅脑损伤组:局灶 性脑组织表面血管破裂致出血，血液流入蛛网膜下腔，大鼠脑皮质分 子层，外颗粒层等部位受挫伤，其周边仍可见神经细胞存在，细胞质 伊红染色程度加深;神经元、星形胶质细胞、小胶质细胞等周边间隙 加大。中度颅脑损伤组:顶叶部位脑组织表面血管破裂致出血，血液 流入蛛网膜下腔，大鼠脑皮质分子层，外颗粒层，外锥体细胞层，内 颗粒层，内锥体细胞层等处受挫伤，伴有不同程度的出血，变性、坏 死的神经元增多。重度颅脑损伤组:顶叶脑组织表面血管破裂致出血， 血液流入蛛网膜下腔，有些可出现硬膜下血肿;挫伤灶除可见于大鼠 脑皮质分子层，外颗粒层，外锥体细胞层，内颗粒层，内锥体细胞层， 多形细胞层等,还见于白质深处的胼胝体、海马等。变性、坏死的神 经元进一步增多。结论TBI中ACH与BDNF在脑组织含量变化呈正相 关，且与损伤程度有关，通过ACH与BDNF脑组织含量可以间接反映 TBI病变及损伤程度,有可能为临床脑损伤的治疗、损伤程度及预后 的判断提供新的方法。 【英文摘要】0bjective:To explore the profiles of acetylcholine (Ach)and brain-derived neurotrophicfactor(BDNF) in rat models of traumatic brain injury(TBI).Methods:192 healthy male SD rats (weight 250g,300g)were randomized into theinjury(n=144) and control groups(n=48)(The injury group was further divided randomly into 3secondary groups based on severity of injury(mild，moderate and severe，n=48 eAch)(Theseinjury—graded groups and control group were again stratified into 8sub-groups according totime from TBI(15min， 0.5，1，3，6，1 2，24 and 48 h)，such that every sub—group had 6 rats(Tocreate TBI models，the rats assigned to injury group received different powers delivered withreference to FEENEY’ S method. Injury groups’rats were respectively given the different power(200g(cm、600g(cm and 1000g.cm)by the equipment of hitting by freely falling，and thenthe rats were made into three types of traumatic brain injury models. Immediately after theinjury and at specific time spots，hippocampus and cortex samples were collected from eAchrat. The brain tissue 1evels of Ach and BDNF were measured with ELISA method(Part ofbrain tissues were also examined by hematoxylin-eosine dyeing method in order to study thehistopathological changes.Results: (1)There was a positive correlation between post—TBI brain tissue 1evels of Achand BDNF(rank correlation coefficient: Hippocampus samples r_s=0.340，P<0.01; cortexsamples r_s=0.311，P<0.01)(The changes in brain tissue Ach featured by a sudden rise aftertrauma，a quick decline that ensued and bellowed the normal level(The changes in brain tissueBDNF featured by a gradual rise after trauma，a gradual decline that ensued(The brain tissuelevels of Ach and BDNF varied significantly across all groups with different severity ofTBI(P<0.01)and time from injury(P<0.01)((2) Demonstrate by the light microscope: Mild injury group: The focal subarAchnoidhemorrhage and shallow contusion hemorrhagic in cerebral cortex were observed, theneurons with unclear nucleolus and neuronal cell bodies enhanced in eosinophilic stainingaround contusion were visible.The gap between Neurons and neuroglial cell were widened.Moderate injury group: Parietal subarAchnoid hemorrhage were observed. The cerebral corticalcontused . Neuronal around contusion lesions degenerated .Necrotic area increased. Severeinjury group:parietal subarAchnoid hemorrhage, and even subdural hematoma formed. Contusion lesions were seen in the cerebral cortex,even hippocampus, corpus callosum. Thedegeneration of neuronal around contusion lesions and the scope of necrosis further increased.Conclusion:In traumatic brain injury，both brain tissue levels of Ach and BDNF changeregularly to the degree of injury. Detection of brain tissue Ach and BDNF will be helpful toestimate the degree of injury and pathological changes of the traumatic brain injury( 【关键词】脑损伤 乙酰胆碱 脑源性神经生长因子 【英文关键词】Brain injuries Acetylcholine Brain-derived neurotrophic factor 【目录】创伤性脑损伤大鼠乙酰胆碱、脑源性神经生长因子表达变化的研究 中文摘要 5-6 英文摘要 6-7 中英文缩写词 8-9 前言 9-10 课题和技术策略 10-11 第一章 创伤性脑损伤动物模型的建立 11-19 材料与方法 11-16 结果 16-17 讨论 17-18 附图 18-19 第二章 创伤性脑损伤大鼠脑组织 Ach 及 BDNF 的表达 19-28 材料与方法 19-22 结果 22-26 讨论 26-28 参考文献 28-29 实验结论与展望 29-32 实验结论 29-31 展望 31-32 综述 32-41 参考文献 39-41 个人简历 41-42 致谢 42