脑缺血预处理对大鼠局灶性脑缺血再灌注后自噬及凋亡的影响

发布时间：2018-04-11 07:49

本文选题：自噬 + 凋亡　；参考：《河北联合大学》2014年硕士论文

【摘要】：目的研究脑缺血预处理对大鼠局灶性脑缺血再灌注后自噬及凋亡的影响。方法采用线栓法建立大鼠右侧大脑中动脉缺血预处理和缺血再灌注模型，将实验动物随机分为3组：假手术组、缺血再灌注组及缺血预处理组，各组按照再灌注后2h、6h、12h、24h、3d、5d分为6个亚组，各亚组大鼠在规定时间点行神经功能障碍评分观察神经功能缺损情况，，TTC染色观察脑梗死体积，HE染色观察脑组织病理形态，免疫组织化学染色观察自噬及凋亡相关蛋白Beclin-l、LC3-II、Bcl-2、Caspase-3表达变化，透射电子显微镜观察神经细胞中自噬及凋亡形态结构变化。结果1与假手术组大鼠相比，缺血再灌注组及缺血预处理组大鼠均可见不同程度神经功能缺损、缺血侧大脑半球梗死及梗死区神经细胞损伤。与缺血再灌注组大鼠相比，缺血预处理组大鼠神经功能障碍评分明显减低（P0.05），缺血侧大脑半球梗死体积明显缩小（P0.05），梗死区神经细胞损伤明显减轻。2与假手术组大鼠相比，缺血再灌注组及缺血预处理组大鼠再灌注后各时间点Beclin-l和LC3-II表达不同程度增多。与缺血再灌注组大鼠相比，缺血预处理组大鼠再灌注后各时间点Beclin-l和LC3-II表达不同程度减少（P0.05）。3与假手术组大鼠相比，缺血再灌注组及缺血预处理组大鼠再灌注后各时间点Bcl-2和Caspase-3表达不同程度增多。与缺血再灌注组大鼠相比，缺血预处理组大鼠再灌注后各时间点Bcl-2表达不同程度增多（P0.05），Caspase-3表达不同程度减少（P0.05）。4假手术组大鼠神经细胞未见自噬及凋亡形态结构。缺血再灌注后2h可见少量自噬溶酶体，凋亡仍不明显；缺血再灌注后6h自噬溶酶体数量增多，可见轻度细胞凋亡改变；缺血再灌注后12~24h自噬溶酶体数量增多，细胞凋亡改变程度增加，表现为核染色质块状边集，核形态不规则等，持续到3d；缺血再灌注后5d仍可见自噬及凋亡形态结构。缺血预处理组大鼠与缺血再灌注组大鼠相比，神经细胞自噬及凋亡发生程度减低。结论1脑缺血再灌注可损伤神经细胞，使细胞发生自噬及凋亡，表现为神经功能缺损，缺血侧大脑半球梗死及梗死区神经细胞损伤，自噬及凋亡相关蛋白Beclin-l、LC3-II、Bcl-2和Caspase-3表达显著增加，神经细胞自噬溶酶体数量增多，并出现明显的细胞凋亡改变。2脑缺血预处理对神经细胞具有保护作用，使细胞自噬及凋亡发生程度减低，表现为减少神经功能缺损，缩小缺血侧大脑半球梗死体积及减轻梗死区神经细胞损伤，自噬及凋亡相关蛋白Beclin-l、LC3-II和Caspase-3表达明显减少，Bcl-2表达明显增多，神经细胞自噬溶酶体数量减少，而且细胞凋亡改变程度减低。
[Abstract]:Objective to study the effect of ischemic preconditioning on autophagy and apoptosis after focal cerebral ischemia reperfusion in rats.
Methods to establish the rat middle cerebral artery ischemia preconditioning and ischemia reperfusion model by using suture method, the experimental animal were randomly divided into 3 groups: sham operation group, ischemia reperfusion group and ischemic preconditioning group, each group in 2h after reperfusion, 6h, 12h, 24h, 3D, 5D is divided into 6 sub groups, each sub group of rats at the specified time point for observation of neurological dysfunction score of neurological function, infarct volume was observed with TTC staining, to observe the brain tissue pathological HE staining, observe the autophagy and apoptosis related protein Beclin-l, immunohistochemistry staining of LC3-II, Bcl-2, Caspase-3 expression changes were observed by transmission electron microscopy, nerve cell autophagy apoptosis and morphological changes.
Results 1 rats compared with sham operation group, ischemia reperfusion group and ischemic preconditioning group rats showed different degrees of neurological defects, ischemic cerebral hemisphere infarction and infarction area of nerve cell injury. Compared with ischemia reperfusion rats, ischemic preconditioning group rats decreased obviously (P0.05 nerve function disorder), ischemic cerebral hemisphere infarction volume was significantly reduced (P0.05), nerve cell injury infarct area significantly reduced.2 than those of sham operation group rats, ischemia reperfusion group and ischemic preconditioning group after reperfusion in rats at different time points of Beclin-l and LC3-II expression increased at different degrees. Compared with the ischemia-reperfusion group rats. Ischemic preconditioning group after reperfusion in rats at different time points of Beclin-l and LC3-II expression decreased in different degree (P0.05) of.3 compared with sham operation group, ischemia reperfusion group and ischemic preconditioning group after reperfusion in rats at different time points Bcl-2 The expression of Caspase-3 and increased at different degrees. Compared with the ischemia-reperfusion group rats, ischemia preconditioning group rats after reperfusion, the expression of Bcl-2 in different degree (P0.05) increased, Caspase-3 expression decreased in different degree (P0.05).4 sham operation group rats had no nerve cell autophagy and apoptosis morphology after ischemia reperfusion. 2H is little autolysosome, apoptosis is not obvious; the number of 6h after ischemia reperfusion autophagy lysosome apoptosis cells showed mild changes; ischemia reperfusion 12~24h autophagy lysosome apoptosis change degree is increased, nuclear as well as massive margination of chromatin, nuclear morphology was irregular, sustained to 3D; ischemia after reperfusion, 5D is still visible. Morphology of autophagy and apoptosis in ischemic preconditioning group rats compared with ischemia reperfusion group rats, nerve cell autophagy and apoptosis occurred decreased.
Conclusion 1 cerebral ischemia reperfusion injury of nerve cells, the cell autophagy and apoptosis, manifested as nerve function and ischemic cerebral hemisphere infarction and infarction area of the nerve cells, autophagy and apoptosis related proteins Beclin-l, LC3-II, Bcl-2 and Caspase-3 expression increased significantly, the number of nerve cell autophagy lysosome and apoptosis significantly the change of.2 in cerebral ischemia preconditioning has protective effect on nerve cells, autophagy and apoptosis to decrease, to reduce neurological deficits, reduce ischemic cerebral hemisphere infarction volume and reduce the infarct area of the nerve cells, autophagy and apoptosis related proteins Beclin-l, LC3-II and Caspase-3 expression decreased, Bcl-2 expression increased significantly the number of nerve cells, reduce the cell apoptosis and autophagy lysosome, reduce the degree of change.

【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

【参考文献】