【摘要】 目的 :利用大鼠 4血管结扎的急性脑缺血再灌注模型研究缺血预处理对一氧化氮 (NO)代谢的影响。方法 :实验前 1天将大鼠行双椎动脉烧灼术 ,使其闭合。实验时行微动脉夹同时夹闭双侧颈总动脉。将 3 0只大鼠分为模型组、缺血预处理 (IPC)组和对照组 ,观察血清和脑皮质中NO、自由基变化及神经元型nNOS表达等指标。结果 :模型组大鼠脑内及血清脂质过氧化物 (LPO)、NO水平升高 ,而超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH Px)水平降低 ,较对照组有统计学差异 (P <0 .0 1 ) ,神经元型一氧化氮合酶 (nNOS)表达增加。缺血预处理组上述指标均有改善。模型组和IPC组相比血清中NO含量增加 (P <0 .0 1 ) ,脑皮质中NO含量降低 (P <0 .0 1 )。结论 :缺血预处理可通过抗自由基功能影响NO代谢并保护神经细胞。更多还原

【Abstract】 Objective: To study the effect of NO metabolism and mechanism of ischemic preconditioning in the acute ischemia reperfusion model of rat brain with 4 vessels blocked. Methods: The two carotid vessels were closed with artery nip after the vertebra artery had been cauterized and closed for 1 day . The rats were divided into model group,ischemic preconditioning group(IPC ) and control group. The changes in metabolism of scavenging oxygen free radicals and NO and the expression of nNOS in the cortex and the serum were observed. Results: Compared with the control group, in the model group the concentrations of LPO and NO increased significantly, the activities of SOD decreased distinctly in the cortex and the serum and the exprission of nNOS increased. The parameters of all the items mentioned above were markedly improved in the IPC group compared with the model group. NO concentration increased in the IPC group in the serum and decreased in the cortex. Conclusion: The protective action of preconditioning is related to the scavenging of oxygen free radicals to decrease NO.更多还原