大鼠脑干缺血模型的建立

Study on the Model Foundation of Brainstem Ischemia in Rats

目的:建立稳定的大鼠脑干缺血模型,探讨脑干缺血早期病理改变及其血流变化。方法:雄性Wistar大鼠,手术暴露大鼠基底动脉,于上下两点凝闭基底动脉。应用亚甲蓝和2,3,5氯化三苯基四氮唑盐(TTC)染色确定缺血范围和程度,并分别在基底动脉闭塞后2,6,12,24h处死动物,取脑干组织进行HE和髓鞘染色观察。并应用激光多普勒技术测量基底动脉闭塞前后的血流值。结果:两点电凝基底动脉后亚甲蓝及TTC染色显示缺血区主要位于桥脑及延髓上部小部分区域,基底动脉闭塞后脑干局部血流较闭塞前显著降低。病理学观察可见各时间段脑干组织出现不同程度的神经细胞的缺血性损害,并有髓鞘脱失现象。结论:该模型基底动脉闭塞效果可靠,缺血部位恒定,可用来模拟某些临床过程。

Objective： To establish a stable model of brainstem ischemia in rats, and to explore the pathology and blood flow changes in early stage brainstem ischemia. Methods： Male Wistar rats were used in this study. The basilar arteries were exposed and coagulated at two points. Area and degree of ischemia were defined by methylene and TIC staining. Animals were sacrificed at 2, 6, 12, 24 hours after basilar artery occlusion respectively. Brainstem tissues were observed by HE and myelin sheath staining. The values of blood flow were measured by Laser-Dopplar technique before and after basilar artery occlusion. Results： The ischemic area mainly located at pons and part of superior medulla by methylene and TIC staining after two-point occlusion of basilar artery. Local blood flow in brainstem decreased significantly after basilar artery occlusion compared with that before occlusion. Various degrees of ischemic changes of nerve cells at different observing points and loss of myelin sheath were found by pathological study. Conclusion： The result of basilar artery occlusion is reliable, and the ischemic location is fixed. Some clinical courses can be simulate by this model.