辛伐他汀、阿托伐他汀对脑缺血再灌注大鼠血清MDA、SOD的影响

1、辛伐他汀、阿托伐他汀对脑缺血再灌注大鼠血清MDA、SOD的影响                         作者：袁胜山余昌胤，张骏，蔡志友，陈然  【摘要】  目的 观察阿托伐他汀、辛伐他汀对大鼠脑缺血再灌注血清超氧化物歧化酶(SOD)和丙二醛(MDA)浓度的影响，探讨他汀类药物对脑缺血再灌注后自由基的清除作用。方法 将3

2、6只Wistar大鼠随机分为假手术组，缺血再灌注组，阿托伐他汀预处理高、低剂量组，辛伐他汀预处理高、低剂量组(每组6只)。高、低剂量组分别予6mg/(kg·d)和1.5mg/(kg·d)阿托伐他汀/辛伐他汀灌胃，连续给药7天。用线栓法制备大脑中动脉缺血再灌注模型，缺血2h，再灌注22h。用比色法检测外周血中MDA、SOD的浓度。HE染色观察大鼠脑组织的病理学改变。结果 辛伐他汀、阿托伐他汀预处理各组外周血SOD浓度较缺血再灌注组显著升高、MDA浓度显著降低(P<0.05或P<0.01)。各预处理组之间差异无显著性(P>0.05)。结论 辛伐他汀、阿托伐他汀

3、预处理能提高大鼠脑缺血再灌注后外周血SOD浓度、降低MDA浓度。 【关键词】  脑缺血;再灌注损伤;辛伐他汀;阿托伐他汀;超氧化物歧化酶;丙二醛Simvastatin and atorvastatin influence on serum MDA, SODin rats with focal cerebral ischemia-reperfusion injuryYUAN Sheng-shan1, YU Chang-yin2, Zhang Jun2, CAI Zhi-you2, CHEN Ran3(1. Department of Neurology, Affiliated Hosp

4、ital of Youjiang Medical College for Nationalities,Baise, Guangxi 533000, China; 2. Department of Neurology, Affiliated Hospital of Zunyi MedicalCollege, Zunyi, Guizhou 563003, China; 3. Department of Neurology, Liuan People'sHospital, Liuan, Anhui 237005, China)Abstract: Objective To observe th

5、e influences of simvastatin (Sim) and atorvastatin (Ator) on concentration of serum malondialdehyde (MDA), superoxide dismutase (SOD) in rats with focal cerebral ischemia reperfusion injury and to evaluate the capability of tatin drugs for free radical scavenging. Methods 36 Wistar rats were randoml

6、y divided into: sham ischemic group (Sham group), ischemia-reperfusion group (IR group), and Sim and Ator preconditioning in high and low dose groups, 6 rats in each group. High and low dose groups were respectively oral perfused with 6mg/(kg·d) and 1.5 mg/(kg·d) for 7 days continuously. T

7、o produce the focal cerebral ischemia-reperfusion injury model, the middle cerebral artery of rat was occluded by inserting a nylon suture through the internal carotid artery for 2h, followed by reperfusion for 22h after withdrawing the suture. The serum concentration of SOD and MDA was measured by

8、the chemical colorimetry, the pathological feature of cerebral tissue was detected by HE staining. Results Compared to IR group, Sim and Ator preconditioning groups in serum concentration of SOD were significantly higher (P<0.05). The serum concentration of MDA in Sim and Ator preconditioning gro

9、ups was significantly lower than that in IR group (P<0.05 or P<0.01). Among the preconditioning groups there was no significant difference (P>0.05). Conclusion Simvastatin and atorvastatin can increase the serum concentration of SOD and decrease the concentration of MDA in rats with focal c

10、erebral ischemic-reperfusion injury, they can protect neural function by enhancing clearance of free radical.Key words: brain ischemia; reperfusion injury; simvastatin; atorvastatin; superoxide dismutase; malondialdehyde缺血性脑损害是多种致病机制共同作用的结果，其中氧自由基损伤为重要且肯定的因素之一。近年来的研究表明1,2，他汀类药物具有多向性神经保护作用。在国内外研究中，他汀

11、类药物对急性缺血性脑血管病血清超氧化物歧化酶(SOD)和丙二醛(MDA)的影响报道较少。本实验采用不同剂量辛伐他汀和阿托伐他汀预处理,观察其对大鼠血清SOD、MDA浓度的影响,以探讨辛伐他汀对脑缺血再灌注的保护作用机制。1 材料和方法1.1 实验动物与分组 雌性Wistar大鼠36只，体重200250mg，购于第三军医大学野战医院动物研究所，清洁级，动物中心许可证号:渝实动设施准第260 号。采用单纯随机原则分为：假手术组(Sham组)、缺血再灌注组(IR组)、阿托伐他汀预处理高剂量组(H-Ator组)和低剂量组(L-Ator组)、辛伐他汀预处理高剂量组(H-Sim组)和低剂量组(L-Sim组

12、)，每组6只。术中出血较多、出现呼吸困难、取脑时发现蛛网膜下腔出血及提前死亡者剔除，并补足相应例数。1.2 给药方法 药物剂量参照Db=Da×Rb/Ra(Wa/Wb)1/3计算3，给药时间以血药浓度达稳定为依据。低、高剂量组分别予1.5mg/(kg·d)、6mg/(kg·d)辛伐他汀/阿托伐他汀，用生理盐水配成0.3mg/ml和1.2mg/ml混悬液，每天1次连续灌胃7天。Sham组与IR 组均予等量生理盐水灌胃。1.3 动物模型制作及标本收集 除Sham组外，其余各组参照文献4，5描述的大脑中动脉线栓方法制作大鼠脑缺血再灌注模型。Sham组插入线栓长度约1cm

13、，其余步骤同其他组。大鼠苏醒后，除Sham组外，其余各组参考Longa等6的5分评分法，2分或2分以上者入选本实验。各组分别于缺血2h再灌注22h后，断头取脑，留取血标本。1.4 SOD和MDA检测方法 化学比色法：MDA采用硫代巴比妥酸法测定;SOD采用黄嘌呤氧化酶法。试剂均采用南京建成生物工程研究所的试剂盒。操作步骤严格按照说明书进行。仪器采用上海产721型分光光度计。1.5 统计学分析 计量资料采用单因素方差分析，进一步进行两两比较。全部数据采用SPSS 12.0软件包进行统计学处理。2 结果2.1 各组大鼠脑组织病理学改变 光镜下Sham组大鼠皮层各层细胞排列整齐，神经元结构完整;IR

14、组HE染色见脑组织坏死明显，白质内小血管周围有大量淋巴细胞、巨噬细胞等炎性细胞浸润。Sim组和Ator组坏死面积较IR组小，白质内小血管周围有少量淋巴细胞、巨噬细胞等炎性细胞浸润(见图1图4)。2.2 各组大鼠外周血SOD浓度和MDA浓度 见表1。实验结果显示，缺血后SOD、MDA浓度均下降，IR组下降最为显著(P<0.01)。与IR组比较预处理组可以显著提高血清SOD浓度，降低MDA含量，差异有显著性(P均<0.05)，其中，L-Ator和H-Sim两组差异有高度显著性(P<0.01)。各预处理组之间比较差异无显著性(P>0.05)。图1 Sham组大鼠脑组织 HE染色(×400)。可见细胞排列整齐神经元结构完整。 图2 IR组大鼠脑组织 HE染色(×400)。可见细胞大量缺失坏死，有广泛的炎性细胞浸润。 图3 Sim预处理组大鼠脑组织 HE染色(×400)。显示梗塞范围较小，坏死较IR组轻，