缺血预适应对局灶性脑缺血再灌注大鼠细胞色素C、凋亡诱导因子表达的实验研究

发布时间：2018-07-05 18:10

本文选题：缺血预适应 + 脑缺血再灌注损伤　；参考：《河北联合大学》2014年硕士论文

【摘要】：目的通过观察缺血预适应对局灶性脑缺血再灌注后大鼠神经功能缺损评分、脑梗死体积、病理组织学损伤的影响及缺血灶周围皮质区及海马CA1区细胞色素C（CytC）、凋亡诱导因子（AIF）表达的变化，探讨缺血预适应的脑保护作用方法采用线栓法制备雄性SD大鼠局灶性脑缺血再灌注改良模型，将100只大鼠随机分为假手术组（SO组）、缺血组（MCAO组）、预适应组（BIP组），其中MCAO组与BIP组分别于缺血2h再灌注2h、6h、12h、24h、48h、72h时间点处死，每时间点5只。每组于再灌注6h、24h、72h时间点各多5只大鼠做TTC染色，进行脑梗死体积的测定；SO组于24h时间点处死，取5只大鼠进行TTC染色。处死大鼠前各组均行神经功能缺损评分，各组大鼠脑组织切片行HE染色，并观察组织病理学改变、原位末端标记（TUNEL染色法）观察缺血灶周围皮质区及海马CA1区凋亡神经元数、免疫组化染色观察缺血灶周围皮质区及海马CA1区CytC、AIF阳性神经元的表达结果1神经功能缺损评分、脑梗死体积及脑组织病理形态学观察：SO组未见神经功能缺损症状、缺血灶及脑组织病理性改变。与MCAO组对比，BIP组在再灌注各时间点神经功能缺损评分低、缺血灶体积百分比小、脑组织病理学改变轻。2SO组皮质区、海马CA1区可见1~2个TUNEL染色阳性神经元表达。MCAO组和BIP组缺血灶周围皮质区及海马CA1区TUNEL染色阳性神经元数均于缺血再灌注2h开始增加，之后随再灌注时间的延长TUNEL染色阳性神经元数逐渐增高，缺血灶周围皮质区及海马CA1区再灌注24h在各观察时间点中表达水平最高，随后随再灌注时间点变化，表达有下降趋势，组内相邻时间点比较，差异有统计学意义（P0.05）；在相同时间点BIP组缺血灶周围皮质区及海马CA1区TUNEL染色阳性神经元数量较MCAO组明显减少，差异有统计学意义（P0.05）；与SO组比较，，MCAO组和BIP组各时间点TUNEL染色阳性神经元表达均增高，差异有统计学意义（P0.05）。3SO组皮质区、海马CA1区均可见少量CytC阳性神经元表达；MCAO组和BIP组缺血灶周围皮质区及海马CA1区CytC阳性神经元表达均于缺血再灌注2h开始增加，随再灌注时间的变化CytC阳性神经元表达呈增高趋势，再灌注24h在各时间点表达水平最高，组内相邻时间点比较，差异有统计学意义（P0.05）；在相同时间点BIP组缺血灶周围皮质区及海马CA1区CytC阳性神经元表达数量较MCAO组明显减少，差异有统计学意义（P0.05）；与SO组比较，MCAO组和BIP组各时间点CytC阳性神经元表达均增高，差异有统计学意义（P0.05）。4SO组皮质区、海马CA1区均有少量AIF阳性神经元表达；MCAO组和BIP组缺血灶周围皮质区及海马CA1区AIF阳性神经元表达趋势基本一致，均于缺血再灌注2h表达开始增加，之后随时间的延长表达逐渐增多，在皮质区再灌注48h在各时间点表达水平最高，海马CA1区于再灌注24h在各时间点表达水平最高，组内相邻时间点比较，差异有统计学意义（P0.05）；在相同时间点BIP组缺血灶周围皮质区及海马CA1区AIF阳性神经元表达数量较MCAO组明显减少，差异有统计学意义（P0.05）；与SO组比较，MCAO组和BIP组各时间点AIF阳性神经元表达均增高，差异有统计学意义（P0.05）。结论1缺血预适应后局灶性脑缺血再灌注大鼠神经功能缺损评分降低、脑梗死体积减小、脑组织病理组织学损伤减轻，有效地减轻了脑缺血再灌注损伤。2缺血预适应后局灶性脑缺血再灌注大鼠缺血灶周围皮质区及海马CA1区神经细胞凋亡减少，起到脑保护作用。3缺血预适应后局灶性脑缺血再灌注大鼠缺血灶周围皮质区及海马CA1区CytC、AIF的表达减少，可能通过抑制CytC、AIF的表达，抑制凋亡的发生
[Abstract]:Objective To observe the effects of ischemic preconditioning on neurological deficit score, cerebral infarction volume, histopathological injury, cytochrome C (CytC) and apoptosis inducible factor (AIF) expression in the cortex and hippocampus CA1 area around the ischemic area, and to explore the protective effect of ischemic preconditioning on cerebral protection.
Methods the improved model of focal cerebral ischemia reperfusion in male SD rats was prepared by thread emboli, and 100 rats were randomly divided into sham operation group (group SO), ischemia group (group MCAO) and pre adaptation group (group BIP), of which group MCAO and BIP were reperfusion with 2H, 6h, 12h, 24h, 48h, and 5 rats at each time point. At the time point, 5 rats were stained with TTC, and the volume of cerebral infarction was measured. Group SO was killed at the time point of 24h and 5 rats were stained with TTC. The nerve function defect scores were performed in each group before the death of rats. The brain tissue sections of each group were stained with HE, and the histopathological changes were observed, and the site terminal labeling (TUNEL staining) was used to observe the focal ischemia. The number of apoptotic neurons in the peripheral cortex and hippocampus CA1 area was observed. The expression of CytC and AIF positive neurons in the cortex and hippocampus CA1 area of ischemic foci was observed by immunohistochemical staining.
Results 1 nerve function defect score, cerebral infarction volume and brain tissue pathomorphology observation: in group SO, no neurological deficit symptoms, ischemic foci and pathological changes of brain tissue were not found. Compared with group MCAO, the score of nerve function defect in group BIP was low, the percentage of ischemic focus was small, and the pathological changes of brain tissue were light in group.2SO. In the CA1 region of the hippocampus, the expression of 1~2 TUNEL staining positive neurons expressed in the.MCAO group and the number of TUNEL staining positive neurons in the cortical area around the ischemic foci and the CA1 region of the BIP group began to increase, and the number of positive neurons in the TUNEL staining increased gradually with the time of reperfusion, and the cortical area around the ischemic focus and the CA1 region of the hippocampus were reformed. The expression level of perfusion 24h was the highest in each observation time point, then the expression decreased with the time point of reperfusion, and the difference was statistically significant (P0.05). The number of TUNEL staining positive neurons in the cortex and hippocampus CA1 region of BIP group at the same time point was significantly lower than that in the MCAO group, and the difference was found. Statistical significance (P0.05); compared with group SO, the expression of TUNEL staining positive neurons in each time point of group MCAO and BIP increased, the difference was statistically significant (P0.05) in the cortical area of the.3SO group, and the expression of a small amount of CytC positive neurons in the hippocampal CA1 area; the expression of the positive neurons in the peripheral cortex and the hippocampal CA1 region of the MCAO and BIP groups were all in the MCAO group and the BIP group. The expression of CytC positive neurons was increased with the change of reperfusion time, and the expression level of 24h at each time point was the highest. The difference was statistically significant (P0.05) in the adjacent time points in the group (P0.05), and the expression of CytC positive neurons in the peripheral cortex and CA1 region of the hippocampus at the same time point was in the same time point. The expression of CytC positive neurons in the BIP group of BIP group and the hippocampal CytC positive neurons were in the same time point. Compared with group MCAO, the difference was statistically significant (P0.05). Compared with group SO, the expression of CytC positive neurons in each time point of group MCAO and BIP group increased, the difference was statistically significant (P0.05) in the cortex area of.4SO group, and a small amount of AIF positive neurons in the CA1 region of the hippocampus, and the MCAO group and the cortex of the ischemic foci in the BIP group and the hippocampal region. The expression trend of sexual neurons was basically the same, the expression of 2h in ischemic reperfusion began to increase, and then increased with time. The expression level of 48h in cortical area was the highest at all time points, and the expression level of 24h in hippocampus CA1 region was the highest at all time points, and the difference was statistically significant in the adjacent time points in the group (P0.05 In the same time point, the number of AIF positive neurons in the cortex and hippocampal CA1 area of the BIP group was significantly lower than that in the MCAO group, and the difference was statistically significant (P0.05). Compared with the SO group, the expression of AIF positive neurons in each time point of group MCAO and BIP group increased, and the difference had the significance (P0.05).
Conclusion 1 after ischemic preconditioning, the score of neural function defect in focal cerebral ischemia reperfusion rats decreased, the volume of cerebral infarction decreased, and the injury of brain histopathology decreased, which effectively alleviated the cerebral ischemia reperfusion injury of cerebral ischemia reperfusion injury in the cortex and CA1 region of the hippocampus after.2 ischemic preconditioning. The expression of CytC and AIF in the cortex and CA1 region of the hippocampus of rats with focal cerebral ischemia reperfusion after ischemic preconditioning.3 decreased, and the expression of AIF may be inhibited by inhibiting the expression of CytC and AIF and inhibiting the occurrence of apoptosis.
【学位授予单位】：河北联合大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R743.3

【参考文献】