椎动脉阻断对犬中枢神经系统功能的影响

目的：研究椎动脉阻断对小脑组织及颈脊髓功能的影响。方法：将杂种家犬按处死时间分为1d组,7d组,28d组及对照组,每组5条犬,结扎犬颈4,颈5水平双侧椎动脉,于术后1,7,28d分别观察犬行为,诱发电位,颈脊髓与小脑后下叶的影像,组织学的变化及毛细血管灌注的定量分析。结果：术后1d组动物出现轻度缺血性损害,其余动物椎动脉阻后小脑后下叶及颈脊髓组织无明显改变。结论：颈内动脉可以短期内完成对椎动脉阻断后的缺血代偿,椎动脉血流障碍并非椎动脉型颈椎病的主要病理机制,而该动物模型可以节段性模拟人类颈脊髓的微循环。

Impact of ligation of vertebral artery on function of central nervous system, an experimental study

OBJECTIVE: To study the impact of ligation of bilateral vertebral arteries on the function of central nervous system. METHODS: Twenty dogs underwent ligation of bilateral vertebral arteries at the level of C4 approximately C5 and then were divided into 4 groups, 5 in each: E1 group (killed in one day after the operation), E7 (killed on the 7(th) day postoperatively), E28 (killed on the 28(th) day postoperatively), and control group. Scoring of the function of central nervous system was conducted after awakening from anaesthesia and before being killed according ro modified Tarlov method. Cortical somatosense evoked potential (CSEP), and motor evoked potential (MEP) were examined by electromyograph. CT, MRI, and magnetic resonance angiography (MRA) of the cervical vertebrae were conducted before the dogs were killed. Histological examination of the spinal cord and brain was made and microangiography was performed. RESULTS: The myodynamia, gait, and reflex returned to normal 2 approximately 3 days after the operation with the Tarlov score of 6 for all dogs. Imaging examination and histological examination showed no abnormality, including ischemic injury in posterior inferior lobe of cerebellum. CONCLUSION: Internal carotid artery compensates for the blood obstruction of the vertebral artery in a short time. Cerebral ischemia caused by compression of the vertebral artery is not the main pathomechanism of cervical spondylotic arteriopathy. Microcirculation of human cervical cord can be mimicked in dog model segmentally.