构建全脑缺血与鞘内置管结合的SD大鼠模型

背景：脑缺血性损伤可导致神经元不可逆性功能丧失,而鞘内用药是目前临床镇痛及神经保护类药物的常用施药途径。大脑损伤后可于鞘内注入神经保护类物质进行干预的实验动物模型是相关神经保护类物质研究的基础。目的：构建全脑缺血与鞘内置管相结合的动物模型。 方法：采用Pulsinelli四血管阻断全脑缺血模型结合鞘内置管术,将实验大鼠进行四血管阻断与鞘内置管,另设置假手术组不进行血管阻断。术后除假手术组外,一部分大鼠注射虎纹蜘蛛毒素Ⅰ (1.0 µL/kg),设为虎纹蜘蛛毒素Ⅰ组;另一部分大鼠注射等量生理盐水,设为模型组。缺血再灌注4 d后用尼氏染色观察脑组织海马CA1区锥体神经元结构的变化。结果与结论：假手术组可见大量锥体神经元,排列整齐紧密,胞浆染色清晰,呈蓝色,胞浆内尼氏体均匀丰富。虎纹蜘蛛毒素Ⅰ组锥体神经元排列较整齐,稀疏分布,出现少量胞体浓缩、深染,细胞体积缩小等特征。模型组可见锥体神经元排列散乱,层次不完整,稀疏分布,出现大量胞体浓缩、深染,细胞体积缩小等特征。虎纹蜘蛛毒素Ⅰ组相比模型组大鼠海马CA1区锥体神经元受损程度变小。结果提示,实验成功构建了全脑缺血与鞘内置管相结合的大鼠模型。

Establishment of global cerebral ischemia combined with intrathecal catheterization models in Sprague-Dawley rats

BACKGROUND:Cerebral ischemia-reperfusion injury can result in irreversible neuronal function loss, whereas intrathecal administration of analgesia and neuroprotective drugs has been frequently used in the clinic. The animal models undergoing intrathecal administration of neuroprotective substances after cerebral injury are the basis of studies on the effects of neuroprotective substances.OBJECTIVE:To establish animal models of global cerebral ischemia combined with intrathecal catheterization for drug admistration. METHODS:Global cerebral ischemia was induced by four-vessel occlusion method and intrathecal catheterization was performed. Rats were randomly assigned to three groups with 10 rats per group: sham-surgery, model, and huwena toxin-Ⅰ (HWTX-Ⅰ). Rat models of global cerebral ischemia were established and intrathecal catheterization for drug administration was performed in the model and HWTX-Ⅰ groups. After model establishment, rats from the HWTX-Ⅰ group received HWTX-Ⅰ(1.0 µL/kg), and rats from the model group received the same amount of physiological saline. At 4 days after ischemia/reperfusion, Nissl staining was performed to observe the morphological changes of pyramidal neurons in rat hippocampal CA1 region. RESULTS AND CONCLUSION:In the sham-surgery group, numerous pyramidal neurons were densely and orderly arranged, endochylema was blue-stained, and Nissl body staining was even. In the HWTX-Ⅰ group, pyramidal neurons were orderly arranged, sparsely distributed, and some neuronal bodies were atrophic and darkly stained. In the model group, pyramidal neurons were disorderly arranged, and sparsely distributed in the whole CA1 region; in addition, a large number of neurons were atrophic and darkly stained. There was a larger degree of morphological change of hippocampal CA1 region pyramidal neurons in the HWTX-Ⅰ group than in the model group. Results indicate that rat models of global cerebral ischemia combined with intrathecal catheterization were successfully established.