阿魏酸钠对缺血预处理后大鼠脑缺血再灌注损伤的保护作用

背景:缺血性脑损伤后,如何减少神经细胞的死亡促进神经功能的恢复?脑缺血预处理在一定程度上可减轻再次缺血导致的缺血性脑损伤。阿魏酸钠亦被证实能减少脑缺血后的神经元凋亡的发生。而阿魏酸钠是否能增强脑缺血预处理的神经保护作用?目的:探讨阿魏酸钠联合缺血预处理对脑缺血再灌注损伤的保护作用。设计:随机对照动物实验。单位:江西医学院第二附属医院神经外科,江西医学院生理教研室,江西医学院泌尿外科研究所。材料:实验于2001-05/2002-04在江西医学院第二附属医院神经外科实验室完成。雄性Wistar大鼠85只,体质量250～300g。方法:大鼠随机分为四组:①非缺血对照组(10只):仅结扎双侧椎动脉而不夹闭双侧颈总动脉。②缺血对照组(25只):结扎双侧椎动脉48h,夹闭颈总动脉10min。③缺血预处理组(25只):结扎双侧椎动脉48h,夹闭颈总动脉2min后24h再次夹闭颈总动脉10min。④阿魏酸钠联合缺血预处理组(25只):缺血预处理后,再次夹闭颈总动脉前30min,尾静脉注射阿魏酸钠(200mg/kg)。非缺血对照组分为再灌注后2,7d二个亚组(各5只);缺血对照组、缺血预处理组及阿魏酸钠联合缺血预处理组又分为再灌注后6,12,24h,2,7d五个亚组(各5只)。各组在相应时点将大鼠断头取脑,于视交叉后2.2mm切取冠状脑片,观察阿魏酸钠联合缺血预处理在脑缺血再灌注时对皮层和海马CA1区神经元数及凋亡细胞数的影响。主要观察指标:皮层和海马CA1区神经元数及凋亡细胞数。结果:实验大鼠85只均进入结果分析。①大脑皮层及海马CA1神经元计数:缺血7d时,缺血预处理组和阿魏酸钠 缺血预处理组高于缺血对照组(268±8.5,244±12.5,135±5.6,P<0.01)。②大脑皮层及海马CA1区TUNEL阳性细胞计数:阿魏酸钠 缺血预处理组低于缺血预处理组和缺血对照组(12h:1.2±0.8,15.5±2.1,39.8±3.9;24h:1.8±1.6,39.3±11.8,191.3±19.1;2d:2.8±1.2,68.3±13.6,328.4±24.0,P<0.01);缺血预处理组低于缺血对照组(P<0.01)。结论:缺血预处理可减少缺血区神经元凋亡细胞数,阿魏酸钠联合缺血预处理可以进一步加强此效应,对脑缺血再灌注损伤起保护作用。

Protection of sodium ferulate on cerebral ischemic-reperfusion injury in rats after ischemic preconditioning

BACKGROUND: How to lessen neuronal necrosis to promote recovery of nerve function after ischemic cerebral injury? Cerebral ischemic preconditioning (IP) alleviates ischemic cerebral injury caused by re-ischemia to certain extent. It has been verified that sodium ferulate can lessen the incidence of neuron apoptosis after cerebral ischemia. Whether does sodium ferulate enhance the nerve protection of IP brain to not?OBJECTIVE: To explore the protection of sodium ferulate allied with IP in cerebral ischemic-reperfusion injury.DESIGN: Randomized controlled animal experiment was designed.SETTING: Neurological Surgery Department of 2nd Affiliated Hospital of Jiangxi Medical College, Department of Physiology of Jiangxi Medical College, Institute of Urinary Surgery of Jiangxi Medical College.MATERIALS: The experiment was perforned in Laboratory Room of Neurological Surgery Department of 2nd affiliated Hospital of Jiangxi Medical College from May 2001 to April 2002, in which, 85 Wistar male rats were employed, mass weighted varied from 250-300 g.METHODS: The rats were randomized into 4 groups: ① The control without ischemia (10 rats): Vertebral artery was ligatured bilaterally and common carotid artery was not clipped bilaterally. ② The control with ischemia (25 rats): Vertebral artery was ligatured bilaterally for 48 hours and common carotid artery was clipped for 10 minutes. ③ IP group (25rats): Vertebral artery was ligatured bilaterally for 48 hours and common carotid artery was clipped for 2 minutes, and 24 hours later, the common carotid artery was clipped again for another 10 minutes. ④ Sodium ferulate allied with IP group (Allied group) (24 rats): After IP, the common carotid artery was clipped again for 30 minutes and sodium ferulate (200 mg/kg)was injected intravenously from tail. The control without ischemia was subdivided into two groups of 2 days and 7 days after reperfusion respectively (5 rats for each one). The control with ischemia, IP group and allied group were subdivided into 5 groups of 6 bours, 12 hours, 24 hours,2 days and 7 days after reperfusion successively (5 rats for each one).The rats were sacrificed to collect brains at phase spots in each group.Coronary brain slice was collected 2.2 mm posterior to the optic chiasm and the effects of allied with was observed on neuron count and apoptotic cell count in cortex and hippocampal CA1 in cerebral ischemia reperfusion.MAIN OUTCOME MEASURES: Neuron count and apoptotic cell count in cortex and hippocampal CA1.RESULTS: Totally 85 experimental rats all entered result analysis. ①Neuron count in cerebral cortex and hippocampal CA1: On the 7th day after ischemia, the counts in IP group and allied group were higher than ischemia control (268±8.5, 244±12.5, 135±5.6, P ＜ 0.01). ② Count of TUNEL positive cell in cerebral cortex and hippocampal CA1: The count in allied group was lower than that in IP group and ischemia control (12 hours:1.2±0.8, 15.5±2.1, 39.8±3.9; 24 hours: 1.8±1.6, 39.3±11.8, 191.3±19.1;2 days: 2.8±1.2, 68.3±13.6, 328.4±24.0, P ＜ 0.01), and that in IP group was lower than ischemic control (P ＜ 0.01).CONCLUSION: IP lessens apoptotic neuron count in ischemic region.Sodium ferulate allied with IP further intensifies such effect and provides the protection of ischemic reperfusion injury of brain.