【作者】 巴迎春；

【导师】 王廷华； 潘兴华；

【作者基本信息】 昆明医学院 ， 人体解剖与组织胚胎学， 2004， 硕士

【摘要】 目的：建立慢性轻、重度大鼠脑缺血的动物模型，观察慢性脑缺血时皮质、海马中的NGF、BDNF、NT-3的表达变化，探讨缺血性脑损伤及修复机制。方法：结扎右颈总动脉和双侧颈总动脉分别制作出慢性轻度脑缺血和慢性重度脑缺血的Wistar大鼠动物模型，分三个组：假手术对照组、慢性轻度脑缺血组(30天、120天)、慢性重度脑缺血120天组，除慢性轻度脑缺血组因有两个时间段，故有10只Wistar大鼠，其余每个组5只。分别于手术后30天、120天处死动物，取脑组织进行冰冻连续冠状切片，片厚20μm，分别用兔抗NGF(1：200)、BDNF(1：200)、NT-3(1：200)抗体进行免疫组化ABC法染色，计数皮质、海马中这三种因子的阳性神经元数。用q检验及配对T检验进行统计分析。结果：1．在对照组的皮质、海马中都可见三种因子较强的表达。2．NGF：在轻度脑缺血时，皮质中NGF的表达在缺血第30天下降，低于对照组(P＜0.05)，第120天比第30天增强(P＜0.05)，但与对照组无显著性差异(P＞0.05)；重度脑缺血120天时，与轻度脑缺血120天及对照组都无显著性差异(P＞0.05)。在海马，当轻度脑缺血第30天时，NGF的表达与对照组无显著性差异(P＞0.05)，到第120天时，NGF的表达比对照组强(P＜0.05)，与30天时无显著性差异(P＞0.05)；但在重度脑缺血120天时与轻度脑缺血120天及对照组都无显著性差异(P＞0.05)。3．BDNF：在轻度脑缺血30天时，皮质、海马的BDNF表达与对照组无显著性差异(P＞0.05)。在皮质，轻度脑缺血120天时，与对照组无显著性差异(P＞0.05)，但低于轻度脑缺血30天(P＜0.05)；轻度脑缺血120天时，海马的BDNF表达高于轻度脑缺血30天(P＜0.05)，与对照组无显著性差异(P＞0.05)。而当重度脑缺血120天时，在皮质，与轻度脑缺血120天及对照组比较都无显著性差异(P＞0.05)；在海马，比轻度脑缺血120天及对照组都增强(P＜0.05)。4．NT-3：在轻、重度脑缺血时，皮质、海马的NT-3表达与对照组都无显著性差异(P＞0.05)。结论：1．NGF、BDNF、NT-3能表达于硕士研究生学位论文慢性脑缺血大鼠皮质、海马中NGF、BDNF、NT-3的表达变化正常大鼠的皮质和海马，维持神经元的存活。2.轻度脑缺血30、120天时:在皮质中这三种因子的表达都不高于对照组;在海马中，1加天时，仅NGF的表达高于对照组。3.重度脑缺血120天时，仅海马中的BDNF表达显著增强高于对照组。以上提示:在慢性脑缺血时，这三种因子对海马中的神经元的保护作用可能大于皮质。更多还原

【Abstract】 Objective: to set up the animal model of the chronic light and severe cerebral ischemia, observe the expression of NGF, BDNF, NT-3 in cortex and hippocampus of chronic cerebral ischemia rats, explore the mechanism of ischemia damage and recovery. Method:The chronic light and severe cerebral ischemia rats model were made by clipping respectively right common carotid artery and double common carotid arteries. The rats were divided into three groups: control group, Chronic light cerebral ischemia group (30 days , 120 days) , chronic severe cerebral ischemia group(120 days), every group consisted of five rats, but chronic light cerebral ischemia group consisted of ten rats, because it contained two time points. The rats were sacrificed on the 30th day and the 120th day, the brain tissue of rats were taken out and made into frozen sections 20 μm on the thickness respectively. Then, the sections were stained under same condition using specif icNGF (1:200) , BDNF(1:200), NT-3 (1:200) antibody by ABC method. The positive neurons were counted in each group, all were analyzed by q test or Paired samples T test . Results:1. The expression of the three factors in cortex and hippocampus of control group were apparently seen. 2. NGF: When the light cerebral ischemia of rats occured, the expression of NGF in cortex declined under the level of control group on the 30th day (P<0.05) ,and the expression on the 120th day increased above the expression on the 30th day (P<0.05) , but it had no obvious difference with control group (P>.05) ; on the 120th day after the severe cerebral ischemia of rats occured , the expression of NGF at the time in cortex had no obvious difference with light cerebral ischemia on the 120th day and control group (P>0.05) . In hippocampus, after light cerebral ischemia occured, the expression of NGF on the 30th day had no difference with control group (P>0.05) , the expression on the 120th day increased above control group (P<0.05) ,but had no obvious difference with the expression on the 30th day (P>0.05);however, on the 120th day after the severe ischemia occured, the expression of NGF in hippocampus had no obvious difference with the expression of the 120th day of light cerebral ischemia and the control group (P>0.05) . 3. BDNF: On the 30th day after light cerebral ischemia occured, the expression of BDNF in cortex and hippocampus had no obvious difference with the control group (P>0.05) . On the 120th day after light cerebral ischemia occured, the expression in cortex had no obvious difference with control group (P>0.05) , but it is lower than the expressionof the 30th day of light cerebral ischemia (P<0.05) ; On the 120th day after light cerebral ischemia occured, the expression in hippocampus increased above the expression of the 30th day of light cerebral ischemia (P<0.05) , and had no obvious difference with control group (P>.05) . However , on the 120th day after severe cerebral ischemia occurred, the expression in cortex had no obvious difference with the expression of the 120th day of light cerebral ischemia and control group (P>0.05) ; but the expression in hippocampus of the 120th day of severe cerebral ischemia increased above the expression of the 120th day of light cerebral ischemia and control group (P<0.05) . 3. The expression of NT-3 in cortex and hippocampus didn’ t apparently change with the degree of cerebral ischemia (P>0.05) .Conclusion:1. NGF, BDNF, NT-3 can express in cortex and hippocampus of normal rats, and maintain neurons’ survival. 2. After the light cerebral ischemia of rats occured, on the 30th day or the 120th day, in cortex, the expression of the three factors didn’ t increase above control group ; in hippocampus, on the 120th day, the expression of NGF increased above control group. 3. After the severe cerebral ischemia of rats occured, on the 120th day, only the expression of BDNF in hippocampus apparently increased above control group. 3. The results suggest that the three factors possibly can protect injured neurons more effective in hippocampus than in cortex更多还原