葛根素预处理对局灶性脑缺血再灌注大鼠海马 CA1区神经元损伤的影响及其机制

目的：探讨葛根素预处理对局灶性脑缺血再灌注大鼠海马 CA1区神经元损伤的保护作用及其机制。方法雄性 SD 大鼠30只，随机均等分为假手术组、模型组、葛根素预处理组。采用线栓法阻断大鼠大脑中动脉血供，60 min 后拔出栓线造成局部脑缺血再灌注损伤。葛根素预处理组在缺血前1 h 腹腔注射葛根素（100 mg/ kg ）。脑缺血再灌注后第5天，HE 染色法观察海马 CA1区神经元的组织形态学变化，免疫组化法检测海马 CA1区半胱氨酸天冬氨酸蛋白酶-3（Caspase-3）及半胱氨酸天冬氨酸蛋白酶-9（Caspase-9）的表达。结果 HE 染色结果显示，与模型组相比较，葛根素预处理明显减少脑缺血再灌注引起的海马 CA1区神经元损伤（P<0.05）；免疫组化结果显示，与模型组相比，葛根素预处理使海马 CA1区 Caspase-3、Caspase-9的表达明显降低（ P <0.05）。结论缺血前1 h 葛根素预处理对局灶性脑缺血大鼠海马 CA1区神经元损伤有保护作用，其主要机制可能与抑制凋亡相关蛋白 Caspase-3、Caspase-9的表达有关。

Effects and related mechanisms of preconditioning with puerarin on hippocampus CA1 region neuronal injury after focal cerebral ischemia-reperfusion

Objective To observe the effect of puerarin preconditioning on hippocampal CA1 region neuronal injury and further explore its mechanisms. Methods 30 male Sprague-Dawley rats were randomly assigned into sham, model,and puerarin preconditioning ischemia-reperfusion groups. The middle cerebral artery was occluded for 60 min by an intraluminal filament before reperfusion to induce transient focal cerebral ischemia reperfusion rats. Puer-arin preconditioning groups rats received puerarin(100 mg / kg,i. p)1 h before ischemia. The histological changes of hippocampal CA1 region neurons were measured by HE staining on the 5th day after reperfusion. The expressions of Caspase-3 and Caspase-9 proteins in the CA1 region were examined by immunohistochemistry staining. Results The results of HE staining showed that,compared with the model group,puerarin preconditioning significantly re-duced the number of cerebral ischemia induced injury of hippocampal CA1 region neurons(P < 0. 05). Immunohis-tochemistry data showed that the expressions of Caspase-3 and Caspase-9 in the hippocampal CA1 region of puerarin preconditioning group were significantly lower than that of model group(P < 0. 05). Conclusion The results indi-cate that puerarin preconditioning 1 h before ischemia exerts neuroprotective effects on focal cerebral ischemia-reperfusion induced neuronal injury. The neuroprotective mechanisms of puerarin may attribute to inhibiting the ex-pressions of Caspase-3 and Caspase-9 protein.