蛛网膜下腔出血后皮层微血管及神经元的超微结构改变

目的 观察蛛网膜下腔出血(SAH)后皮层微血管及神经元超微结构的动态变化.方法 将SD大鼠随机分为正常、假手术和手术组,采用改良血管内穿刺法制作大鼠蛛网膜下腔出血的动物模型,通过透射电子显微镜观察不同时间点各组脑组织皮层微血管及神经元的超微结构改变.结果 蛛网膜下腔出血后1 h即可观察到皮层神经元和血管内皮细胞出现轻度水肿,其后水肿逐渐加重,并出现线粒体的嵴膜融合、消失,粗面内质网脱颗粒,毛细血管内皮细胞核固缩,甚至部分微血管闭塞;出血后48 h损伤达到高峰,神经元坏死增多,部分呈裸核改变;随后水肿逐渐减退,于7 d时基本恢复正常.结论 蛛网膜下腔出血后皮层微血管及神经元存在明显的病理性损伤与修复过程,及早保护血管内皮结构与功能的完整,改善微循环功能,对蛛网膜下腔出血的治疗和预后具有重要意义.

Abstract：

Objective To investigate the dynamic ultrastructural changes of micrangiums and neurons in cortex after subarachnoid hemorrhage (SAH). Methods The SD rats were divided into three groups: normal control group, sham-operated control group and SAH group. A modified endovascular perforation model was used to induce SAH in rats. In each group, the brains were collected at different time points for observation on the ultrastructural changes of micrangiums and neurons in cortex under the transmission electron microscopy (TEM). Results The mild edema could be obviously seen in cortex micrangiums and neurons at 1 h after SAH. Thereafter, the edema became serious gradually, membrane and cristae fusion appeared or disappeared, rough endoplasmic reticulum degranulated, and there was pyrosis of capillary endothelial cell nuclei, even blockage of partial capillaries. At the 48th h week aftyer onset of SAH, pathologic changes reached the peak: neurons necrosis increased, and partial showed naked nucleus. Then, the edem was gradually alleviated and returned basically to the normal state at the 7th day.Conclusion There were obviously pathologic changes and repair procedures in cortex micrangiums and neurons after SAH. It was very important for the therapy and prognosis of SAH to protect structural and functional integrity as soon as possible and improve microcirculation.

Ultrastructural changes of micrangiums and neurons in cortex after subarachnoid hemorrhage

Objective To investigate the dynamic ultrastructural changes of micrangiums and neurons in cortex after subarachnoid hemorrhage (SAH). Methods The SD rats were divided into three groups: normal control group, sham-operated control group and SAH group. A modified endovascular perforation model was used to induce SAH in rats. In each group, the brains were collected at different time points for observation on the ultrastructural changes of micrangiums and neurons in cortex under the transmission electron microscopy (TEM). Results The mild edema could be obviously seen in cortex micrangiums and neurons at 1 h after SAH. Thereafter, the edema became serious gradually, membrane and cristae fusion appeared or disappeared, rough endoplasmic reticulum degranulated, and there was pyrosis of capillary endothelial cell nuclei, even blockage of partial capillaries. At the 48th h week aftyer onset of SAH, pathologic changes reached the peak: neurons necrosis increased, and partial showed naked nucleus. Then, the edem was gradually alleviated and returned basically to the normal state at the 7th day.Conclusion There were obviously pathologic changes and repair procedures in cortex micrangiums and neurons after SAH. It was very important for the therapy and prognosis of SAH to protect structural and functional integrity as soon as possible and improve microcirculation.