大鼠颅内动脉瘤模型的建立

目的探讨大鼠颅内动脉瘤动物模型的建市方法。方法SD雌性大鼠60只，随机分为三组，即A组35只：结扎双侧肾动脉后支＋结扎左侧颈总动脉＋术后2％盐水喂养；B组15只：结扎双侧肾动脉后支＋术后2％盐水喂养；C组10只：正常大鼠，未采取任何干预措施。术后12周处死大鼠，观察颅内动脉瘤形成情况及病理学改变。结果A组35只大鼠共出现13个颅内动脉瘤，包括12个睫状和1个梭形脑动脉瘤，成功诱导率为37．14％。光镜下病理学可见动脉瘤壁内膜垫消失，内弹性膜断裂，中膜平滑肌层变薄；电镜下可见中层血管平滑肌细胞的胞核染色质边聚，胞质和胞核浓缩等典型细胞凋广改变。大鼠颅内动脉瘤的组织结构变化与人类脑动脉瘤的超微结构变化极其类似。B组和C组未能诱导出颅内动脉瘤。结论结扎双侧肾动脉后支＋结扎花侧坝总动脉＋高盐饮食喂养诱导的颅内动脉瘤，是研究人类颅内动脉瘤发病机制较可靠的动物模型。

Establishment of a model of intracranial aneurysm in rats

Objective To explore the method of developing a model of intracranial aneurysm in rats.Methods Sixty SD rats were randomly allocated into 3 groups: Group A (n=35) was treated with ligations of left common carotid arteries and posterior branches of bilateral renal arteries, and was fed with 2% saline after procedures; Group B (n=15) was treated with ligations of posterior branches of bilateral renal arteries, and was fed with 2% saline after procedures; and Group C (n=10) served as normal controls without any intervention. Twelve weeks after the procedures, the rats were killed; the formation of intracranial aneurysms and their pathological changes were observed by light microscope and transmission electron microscope.Results Of the 35 rats in group A, 13 intracranial aneurysms were induced, including 12 saccular aneurysms and 1 fusiform aneurysm, and 37.14% was induced successfully. The disappearance of intimal cushion in the wall of aneurysm, the breakdown of internal elastic lamina and the thinner of medial smooth muscle layer were observed under the light microscope; the typical apoptotic changes of the medial vascular smooth muscle cell nucleus chromatin condensation, the concentration of cytoplasm and nucleus were observed under the electron microscope. The changes of histological structure of intracranial aneurysms in rats were extremely similar to the changes of ultrastructure in human cerebral aneurysms. No intracranial aneurysm was induced in Group B and C.Conclusion Ligations of left common carotid arteries and posterior branches of bilateral renal arteries with high salt diet induced intracranial aneurysm are reliable animal model for investigation of the pathogenesis in human intracranial aneurysm.