激光多普勒技术在线栓法制备大鼠脑缺血模型中的应用研究

发布时间：2018-05-01 16:27

本文选题：脑缺血 + 大脑中动脉阻塞　；参考：《新乡医学院》2017年硕士论文

【摘要】：背景脑卒中以其高发病率、高致死率、高复发率的特点,目前是中国居民的第一位死因,给社会及家庭造成了严重的负担。而急性缺血性脑卒中(即脑梗死)是最常见的脑卒中类型,约占全部脑卒中的60%~80%,加强针对其病因、发病机制、预防及治疗的研究,可以为减少其发病率、降低其不良预后率提供更多可选择的途径。而可重复的、对缺血性卒中病理过程有较好模拟性的动物模型是进行相关缺血性脑损伤研究的一个至关重要的因素。线栓法制备的大鼠大脑中动脉闭塞模型是目前应用最多的一种急性局灶性脑缺血模型,其建模方法、梗死体积、神经功能缺失均较稳定,但因缺乏相对客观、便捷的评价手段,仍有一定的建模失败率。激光多普勒脑血流监测可以准确的反应建模期间脑皮质血液灌注的变化程度和持续时间。目的探讨激光多普勒脑血流监测在以线栓法制备大鼠大脑中动脉闭塞模型时的评价作用,为模型制备的评价提供更加客观的标准。方法分别将线栓插入30只SPF级Wistar Han大鼠颈内动脉颅内段(16.0±0.5)、(18.0±0.5)和(20.0±0.5)mm,制备3种局灶性脑缺血模型(各10只)。缺血及再灌注后6 h对所有实验大鼠进行Longa神经行为学评分,然后依据颅底有无血凝块及2,3,5氯化三苯基四氮染色后大脑中动脉供血区有无梗死灶将其分为不全阻塞组、完全阻塞组及过深阻塞组3组,对阻塞颈内动脉颅内段前后及拔出线栓再灌注后每只大鼠大脑中动脉供血区脑皮质的血流量以激光多普勒法进行监测记录并进行统计学分析。大脑中动脉供血区脑皮质的血流量以相对流量单位PU值表示;阻塞后及再灌注后的脑皮质血流量变化以与阻塞前脑皮质血流量的百分比表示。结果模型制作过程中,1只大鼠死亡;纳入不全阻塞组9只,完全阻塞组15只,过深阻塞组5只。不全阻塞组线栓插入深度在(16.0±0.5)mm的大鼠有8只,不能完全阻止大脑前动脉向大脑中动脉的血流,缺血6 h后大鼠Longa评分0~1分;颅底动脉环周围无血凝块,经TTC染色后无梗死灶。完全阻塞组线栓插入深度在(18.0±0.5)mm的大鼠有9只,大脑前动脉的血流被完全阻断,缺血6 h后大鼠存在明显的神经功能缺失,Longa评分2~3分;颅底动脉环周围无血凝块而TTC染色提示存在大脑中动脉供血区的梗死灶。过深阻塞组线栓插入深度在(20.0±0.5)mm的大鼠有5只,可完全阻断大脑前动脉的血流,缺血6 h后大鼠神经功能存在严重缺失,Longa评分3~4分;解剖可见颅底血凝块,TTC染色后可见中动脉供血区梗死灶。插入线栓后,不全阻塞组、完全阻塞组和过深阻塞组大鼠脑皮质血流量均较阻塞前下降(分别为94±17比256±36、43±9比286±44、44±6比294±46,均P0.05),组间差异有统计学意义(F=56.57,P0.01),完全阻塞组和过深阻塞组血流量明显低于不全阻塞组(均P0.05),完全阻塞组与过深阻塞组间差异无统计学意义(P0.05);3组与阻塞前脑皮质血流量的百分比分别为(36.93±0.06)%、(15.09±0.02)%、(15.52±0.04)%,组间差异有统计学意义(F=39.14,P0.01)。再灌注后,不全阻塞组、完全阻塞组和过深阻塞组脑皮质血流量(分别为213±31、147±17、96±14)均较阻塞后有明显回升(均P0.05),组间差异有统计学意义(F=50.05,P0.01),过深阻塞组脑皮质血流量明显低于完全阻塞组(P0.05);3组与阻塞前脑血流量水平百分比分别为(83.10±0.02)%、(51.83±0.05)%、(33.49±0.09)%,差异有统计学意义(F=93.23,P0.01)。以激光多普勒监测的脑皮质血流量变化作为MCAO缺血模型制备成功的判断标准,其灵敏度和特异度要高于神经行为学评分(93.33 vs 80.00,92.86 vs78.57)。结论以激光多普勒对脑血流进行监测,可作为判断线栓法制备大鼠MCAO脑缺血模型成功的一种实时、便捷、微创、客观可靠的评价标准,其灵敏度和特异度均高于神经行为学评分。
[Abstract]:Background cerebral apoplexy, with its high incidence, high mortality and high recurrence rate, is the first cause of death in Chinese residents, causing serious burden to society and family. Acute ischemic stroke (cerebral infarction) is the most common stroke type, which accounts for 60%~80% of all stroke, and strengthens its etiology, pathogenesis, prevention and prevention. And the study of treatment can provide more alternative ways to reduce its incidence and reduce its bad prognosis. But repeatable, a better simulated animal model for the pathological process of ischemic stroke is a vital factor in the study of ischemic brain damage. The rat middle cerebral artery occlusion model is prepared by the thread embolus method. A model of acute focal cerebral ischemia is the most widely used model at present. Its modeling method, infarct volume and neural function loss are all stable. However, there is still a certain failure rate of modeling because of lack of relative objective and convenient evaluation methods. Laser Doppler cerebral blood flow monitoring can be accurate during the process of cerebral cortex blood perfusion during the reaction modeling. Objective to investigate the role of laser Doppler cerebral blood flow monitoring in the evaluation of rat middle cerebral artery occlusion model by thread emboli, and to provide more objective criteria for the evaluation of the model preparation. Methods the thread plug was inserted into the intracranial segment of the internal carotid artery of 30 SPF Wistar Han rats (16 + 0.5), (18 + 0.5) and (20 + 0.5) m, respectively. M, 3 focal cerebral ischemia models were prepared (10 rats each). 6 h after ischemia and reperfusion, all experimental rats were evaluated by Longa neurobehavioral score. Then the infarcts in the middle cerebral artery were divided into incomplete occlusion group based on whether the skull base had blood clots and 2,3,5 chlorination three phenyl four nitrogen, and the total occlusion group and the over deep obstruction group were 3. The blood flow of the cerebral cortex in the cerebral cortex of the middle cerebral artery of each rat after the occlusion of the intracranial segment of the internal carotid artery and the pulling out thread embolus was monitored and recorded by the laser Doppler method. The blood flow of the cerebral cortex in the blood supply area of the middle cerebral artery was represented by the relative flow single PU value; the cerebral cortex after the obstruction and after the reperfusion was carried out. In the process of making the model, 1 rats died, 9 rats were included in the incomplete obstruction group, 15 in the complete obstruction group and 5 in the deep blocking group. The insertion depth of the incomplete occlusion group was 8 in the rats of (16 + 0.5) mm, and the anterior cerebral artery could not be completely prevented from the middle cerebral artery. Blood flow, Longa score 0~1 score of rats after 6 h ischemia; no blood clot around the skull base artery ring, no infarct after TTC staining. There were 9 rats with deep occlusion group insertion depth (18 + 0.5) mm. The blood flow of the anterior cerebral artery was completely blocked. After 6 h of ischemia, the rats had obvious nerve function loss, Longa score 2~3, and cranial artery ring. There was no blood clot around and TTC staining showed the presence of infarct in the middle cerebral artery supply area. There were 5 rats (20 + 0.5) mm in the deep occlusion group, which could completely block the blood flow of the anterior cerebral artery. After 6 h ischemia, the nerve function was seriously missing, the Longa score was 3~4, and the blood clot of the skull base was visible and the TTC staining was visible. Infarcts in the middle artery supply area. The cerebral cortex blood flow of the rats in the complete occlusion group and the over deep block group was lower than that before the occlusion (94 + 17 to 256 + 36,43 + 9, 286 + 44,44 + 6 and 294 + 6, 294 +, respectively, P0.05). The difference between the groups was statistically significant (F= 56.57, P0.01). The blood flow of the complete obstruction group and the over deep block group was clear. There was no significant difference in the total occlusion group (P0.05). There was no significant difference between the complete occlusion group and the over deep obstruction group (P0.05); the percentage of the 3 groups and the obstructive anterior cerebral cortex was (36.93 + 0.06)%, (15.09 + 0.02)%, (15.52 + 0.04)%, and the difference between the groups was statistically significant (F=39.14, P0.01). The cerebral cortex blood flow (213 + 31147 + 17,96 + 14 respectively) in the deep blocking group was significantly higher than that of the obstruction (P0.05). The difference between the groups was statistically significant (F=50.05, P0.01). The cerebral cortex blood flow was significantly lower than that in the complete occlusion group (P0.05), and the percentage of the 3 group and the obstructive forebrain blood flow was (83.10 + 0.02)%, (51.83 + 0.05)%, respectively. (33.49 + 0.09)%, the difference was statistically significant (F=93.23, P0.01). The change of cerebral cortex blood flow measured by laser Doppler was used as a criterion for the success of MCAO ischemia model, and its sensitivity and specificity were higher than that of neurobehavioral score (93.33 vs 80.00,92.86 vs78.57). A real-time, convenient, minimally invasive, objective and reliable evaluation criterion for the success of the rat MCAO cerebral ischemia model prepared by the method of thread emboli was used to evaluate the sensitivity and specificity of the rat model. The sensitivity and specificity of the evaluation were higher than that of the neurobehavioral score.

【学位授予单位】：新乡医学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R743.3;R-332

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