活血化瘀系列方对脑缺血再灌注损伤的保护作用及机制研究

Protective effects and mechanisms of serial TCM "Huoxuehuayu" prescriptions on cerebral ischemia-reperfusion injury in rats

目的 :探讨活血化瘀系列方 (活血汤、活血益气汤、活血养阴汤 )对大鼠脑缺血再灌注损伤的保护作用及其机制。方法 :采用大脑中动脉阻断法制备大鼠脑缺血再灌注模型 ,缺血 6 0 min,再灌注 3d。观察药物对脑缺血再灌注引起的神经功能缺损症状及病理损伤的影响 ,检测脑组织一氧化氮合酶 (NOS)、超氧化物歧化酶 (SOD)活性的变化和丙二醛 (MDA)含量的变化 ,免疫印迹分析 NMDA受体亚单位蛋白 NR1和内皮型 NOS(e NOS)的表达。结果 :活血化瘀系列方及尼莫地平能显著改善神经功能缺失症状 ,减小梗死体积和脑水肿面积 ,减少神经元损伤 (P<0 .0 5 ) ,组间没有显著性差异 ;活血化瘀系列方和尼莫地平不同程度降低脑组织内 NOS活性和 MDA含量 ,抑制NR1表达 ,增加 SOD的活性 ,但对 e NOS的表达均无明显影响。结论 :活血化瘀系列方对大鼠脑缺血再灌注损伤有保护作用 ,其机制可能与降低脑组织内 NOS活性 ,降低 NR1的表达 ,减少 MDA含量和增加 SOD活性有关。

Objective: To determine effects and mechanisms of traditional Chinese medicine serial 'Huoxuehuayu' (activating blood flow and removing blood stasis) prescriptions on cerebral ischemia-reperfusion injury in rats. Methods: Focal cerebral ischemia was induced by 60 min of middle cerebral artery occlusion (MCAO) and followed by 3 d reperfusion. Drugs were orally administered 1 h before MCAO and 4 h after reperfusion and the following 2 d. The neurological scores were evaluated 3 d after reperfusion. Then the animals were sacrificed, the infarct volumes, right and left areas of brain section, the pathologic changes and the normal neurons in hippocampal CA1 and cortex were determined by using an image analyzer. Nitric oxide synthase (NOS), supe-roxide dismutase (SOD) activities and malondialdehyde (MDA) content in brain tissue were evaluated by spectrophotography. The expression of NMDA R1subunit (NR1) and endothelial NOS (eNOS) was determined by immunoblotting technique. Results: Serial 'Huoxuehuayu' prescriptions and nimodipine improved neuronal dysfunction, and reduced infarct size and brain edema. Serial Huoxuehuayu prescriptions and nimodipine reduced MDA content and NOS activity, and increased SOD activity. Western blotting analysis demonstrated induction of NR1. Conclusion: Serial Huoxuehuayu prescriptions have a protective effect on cerebral ischemia-reperfusion injury by reducing NOS activity, MDA content, expression of NR1 and increasing SOD activity.