电刺激背侧中脑导水管周围灰质和再灌注对大鼠脑缺血的作用  

Effects of Dorsal Periaqueductal Gray Stimulation and Reperfusion on Cerebral Ischemic Injury in Rats

作　　者：雷霆[1] 黄慧明[2] 金英雄[1] 杨卓[2] 张涛[1] 

机构地区：[1]南开大学生命科学学院教育部生物活性材料重点实验室,天津300071 [2]南开大学医学院,天津300071

出　　处：《航天医学与医学工程》2007年第3期174-179,共6页Space Medicine & Medical Engineering

基　　金：国家自然科学基金资助项目(30370386;30470453)

摘　　要：目的观察电刺激背侧中脑导水管周围灰质(periaqueductal gray,PAG)和再灌注对SD大鼠脑缺血后的神经损伤和自主神经功能的影响。方法SD大鼠24只随机分为缺血5h组、缺血2h再灌注3h组和脑缺血2h加电刺激dPAG1h组。脑缺血模型采用大脑中动脉阻塞(middle cerebral artery occlusion,MCAO)的方法。实验过程中同时记录血压、心电图和肾交感神经活动。应用功率谱分析技术,获得了心率变异性和肾交感神经活动的频谱特征。计算了TTC染色后的梗死体积。结果电刺激dPAG使缺血后梗死体积减小(P<0.05),并提高自主神经系统的总活性。再灌注使缺血后梗死体积增大(P<0.05),但对缺血后的自主神经功能障碍有很好的改善。结论缺血后再灌注的优势主要在缺血远期,而电刺激有利于脑缺血后的早期恢复并有可能作为再灌注的辅助治疗手段而发挥作用。Objective To investigate the effects of dorsal periaqueductal gray （dPAG） stimulation or reperfusion on neural injury and autonomic dysfunction after cerebral ischemia in rats. Methods Twenty-four male Spague-Dawley rats were randomly divided into three groups： ischemia for 5 h group, ischemia for 2 h plus reperfusion for 3 h group, ischemia for 2 h plus stimulation of dPAG for 1 h group. Cerebral ischemia was induced by intraluminal occlusion of middle cerebral artery. Blood pressure, electrocardiograph and renal sympathetic nerve activity were collected during experiments. Heart rate variability and renal sympathetic nerve activity signals were estimated by power spectral analysis. And infarction volume was measured as well. Results Stimulation of dPAG reduced infarction volume after cerebral ischemia and increased total power of autonomic system and parasympathetic nerve activity. Reperfusion increased infarction volume after cerebral ischemia and increased sympathetic and parasympathetic nerve activites. Conclusion Reperfusion has ascendancy in long-dated effects. Electrical stimulation could be beneficial for early injury after cerebral ischemia and may be an accessorial therapy of reperfusion.

关 键 词：电刺激 再灌注 脑缺血 自主功能障碍 

分 类 号：Q424[生物学—神经生物学]