通络清脑注射液对大鼠脑缺血再灌注致脑水肿的影响

Effects of Tongluo Qingnao Injection on brain edema induced by cerebral ischemia-reperfusion in rats

目的:探讨清热解毒活血中药有效组分配伍通络清脑(TLQN)注射液对大鼠脑缺血再灌注所致脑水肿的影响及其可能的作用机制。方法:60只SD大鼠随机分为假手术组,模型组,尼莫地平组(0.4mg/kg),通络清脑注射液低、中、高剂量组(24、48、95mg/kg),每组10只。线栓法建立大鼠脑缺血模型,1.5h后再灌注,同时经大鼠尾静脉注射相应药物。缺血后24h处死大鼠,取各组脑组织标本及血清,干湿重法检测脑组织含水量,HE染色后观察皮层、海马病理形态变化,免疫组化法分析皮层及海马AQP-4蛋白表达,ELISA法检测血清中TNF-α、IL-6含量。结果:通络清脑注射液高剂量组可显著降低模型大鼠脑指数与脑组织含水量(P<0.01,P<0.05),各剂量组均可不同程度改善缺血再灌注损伤所致的病理形态变化,高剂量组可显著下调模型大鼠皮层、海马AQP-4蛋白表达(P<0.05,P<0.01),各剂量组均可显著降低血清TNF-α含量(P<0.01),中、高剂量组可显著降低血清IL-6含量(P<0.05)。结论:通络清脑注射液具有减轻和改善脑缺血再灌注损伤后脑水肿的作用,其机制可能是通过抑制TNF-α、IL-6的释放,减轻脑内炎症免疫反应,从而抑制脑组织中AQP-4的表达,降低血脑屏障的通透性,对神经功能起到保护作用。

Objective： To explore the protective effect of Tongluo Qingnao （TLQN） Injection on brain edema induced by cerebral ischemia-reperfusion in rats and its possible therapeutic mechanism. Methods： Sixty SD rats were randomly divided into sham-operation group, model group, Nimodipine group （0.4mg/kg）, TLQN low-dose, TLQN medium-dose and TLQN high-dose （24, 48 and 95mg/kg） groups, 10 rats in each group. The rat models of middle cerebral artery occlusion/reperfusion （MCAO/RP） were established by suture-occluded method, 1.5h after ischemia, the drugs were injected via tail vein while reperfusion. 24h after ischemia, the rats were sacrificed, the brain tissues and serum in each group were got, the water content of brain was measured by dry-wet method, the pathological changes of cortex and hippocampus were observed by HE staining, the expression of cortical and hippocampal AQP-4 were analyzed by immunohistochemistry, and the levels of serum TNF-α and IL-6 were detected by ELISA. Results： The brain index and water content of brain were reduced in TLQN high-dose group （P〈0.05, P〈0.01）, the pathologic changes of cortex and hippocampns induced by MCAO/RP were improved at different degrees in all TLQN groups, the expression of cortical and hippocampal AQP-4 were down-regulated in high-dose group （P〈0.05, P〈0.01）. The level of serum TNF-αe was significantly reduced in all TLQN groups （P〈0.01）, and the level of serum IL-6 was reduced in middle-dose group and high-dose group （P〈0.05）. Conclusion： The Tongluo Qingnao Injection could alleviate and improve the brain edema induced by cerebral ischemia-reperfusion injury, and the mechanisms may be related to inhibiting the release of TNF-α and IL-6, alleviating cerebral inflammatory reaction, and then inhibiting the expression of AQP-4, reducing the blood brain barrier permeability, so as to protect the nerve function.