【作者】 于波；

【导师】 王鹤鸣； 韩群颖； 丁炯；

【作者基本信息】 南京医科大学 ， 人体解剖学， 2004， 硕士

【摘要】 目的：观察慢性脑缺血及去势对雌性大鼠行为学、大脑皮质和海马组织病理学、海马CA1区NOS阳性神经元数目的影响。同时探讨补充外源性雌激素替代治疗对去势后上述检测指标的影响。为研究雌激素在慢性脑缺血过程中的保护作用提供形态学基础。 材料和方法：利用双侧颈总动脉永久结扎术(2VO)和卵巢摘除术(OVX)制备动物模型。≥10月龄的雌性SD大鼠随机分为5组：A组，空白对照组，未予处理；B组，假手术组，仅暴露双侧卵巢及双侧颈总动脉，术后予煮沸过的麻油(0.2ml／3d)腹腔注射；C组，单纯缺血组，2VO；D组，雌激素治疗组，OVX+2VO+苯甲酸雌二醇0.2ml／3d腹腔注射；E组，模型组，OVX+2VO+煮沸过的麻油0.2ml／3d腹腔注射。注射至第9周末，进行行为学检测，观察开场实验、T迷宫实验中大鼠反应及表现。常规灌注固定、取含有海马部位的冠状脑块，分为前、后两片。前片做冰冻切片标本，后片做石蜡切片标本。分别做NADPH组织化学染色和HE染色。观察分析神经元形态、海马CA1区存活神经元数目、海马CA1区NOS阳性神经元数目。A、C组各有一只大鼠取海马CA1区组织做电镜标本，观察神经元超微结构的变化。 结果：1、行为学结果显示，慢性脑缺血后大鼠的行为学学习能力下降，而E组的下降最明显。D组雌激素替代治疗后好转。2、HE染色显示缺血后海马顶叶皮质、海马神经元出现不同程度死亡、数目减少；海马CA1区存活神经元数目下降，E组的下降最明显。3、超微结构显示缺血后大鼠神经元细胞核、线粒体等出现变性、溶解等现象。4、C、D、E组海马CA1区NOS阳性神经元数目在慢性脑缺血后也出现减少，去势后，E组NOS阳性神经元减少更加明显，低于补充外源性雌激素的D组。南京医科大学硕上学位论文结论:1、慢性脑缺血能使大鼠行为学能力下降;海马CAI区正常神经元数目减少;细胞器变性、溶解消失、神经元死亡;海马CAI区NOS阳性神经元数目减少。2、去势后，缺少雌激素使各种损伤加重。加用外源性雌激素替代治疗后，出现好转。更多还原

【Abstract】 Objective: To observe the effects of estrogen and chronic brain ischemia on the behavior tests , histopathology , the number of nitric oxide synthase(NOS) positive neurons in hippocampal CA1 area of rats after 2VO(bilateral common carotid occlusion) and OVX(ovariectomy). Furthermore, to study the effects of estrogen replacement on the rats after OVX. Gathering morphologic evidence of the neuro-protection effects of estrogen on the rat chronic brain ischemia.Methods: The animal models were established by 2VO(bilateral common carotid occlusion) and OVX(ovariectomy). 10 months old female Sprague-Dawley rats were randomly divided into 5 groups: A group , control group , with no treatments ; B group , sham-operation group , only bilateral common carotid and ovary were exposed , and boiled sesame 0.2ml/3d after operation were injected into abdominal cavity ; C group, 2VO ; D group, OVX+2VO, and were treated estrogen 0.2ml/3d correspondingly; E group, OVX+2VO, and were treated boiled sesame 0.2ml/3d correspondingly. After 9 weeks, all rats were studied in open field test and T maze test to detect the ability of memory and studying. Then all rats were killed and extracted the pieces of the hippocampus ,which were divided into 2 halves: the anterior half were freezed and sliced to stained by NADPH histochemical method; and the posterior were immersed into wax and sliced for HE staining. We also observed the ultrastructure changes of the neurons in hippocampal CA1 area of the rats of A and C group.Results: 1.It was showed by the behavior tests that the learning and memory abilities of the rats deduced after 2VO and OVX , especially inE group, the D group improved after estrogen treatment. 2.Morphological study demonstrated that the neurons were dead in different grades after 2VO by HE staining , the number of survival neurons of hippocampal CA1 area decreased, especially in E group. 3.Significant changes in neurons and the affiliated structure such as mitochondria were found at the electronic microscopic level. 4.The NADPH histochemical staining showed that the number of NOS positive neurons of hippocampal CA1 area of C, D and E group decreased after 2VO, compared with D group, the E group decreased more obviously.Conclusions: l.The abilities of learning and memory deduced; the number of survival neurons and NOS positive neurons of hippocampal CA1 area decreased; the change of neurons at ultrastructure level were found after 2VO. 2. The impairments were aggravated and the decreasing of NOS positive cells is more significant after OVX, but reversed by the estrogen replacement therapy.更多还原