缺血预处理-后处理对大鼠肠缺血再灌注损伤的影响

Objective To evaluate the effects of ischemic preconditioning-postconditioning on the intestinal ischemia-reperfusion (IR) injury in rats. Methods Forty healthy male SD weighing 225-275 g were randomly assigned into 5 groups ( n = 8 each): group I sham operation (group S) ; group II intestinal IR (group IIR); group Ⅲ ischemic preconditioning (group Ipr); group IV ischemic postconditioning (group Ipo); group V Ipr+ Ipo. The rats were anesthetized with intraperitonel 20% urethane 5 ml/kg. Superior mesenteric artery (SMA) was occluded for 60 min followed by 60 min reperfusion. In group S, SMA was isolated but not occluded. In group Ipr, SMA was occluded for 10 min followed by 10 min reperfusion, and the rest procedures were performed using the method described in group IIR. In group Ipo, 60 min ischemia was followed by three 30 s episodes of ischemia at 30 s intervals for reperfusion. In group Ipr+ Ipo, Ipr was performed followed by Ipo and the procedures were performed using the methods described in group Ipr and Ipo. The animals were killed at 60 min of reperfusion. The intestinal tissues were immediately removed for determination of MDA content, SOD and MPO activities and the degree of damage to intestinal mucous membrane was scored according to Chiu score. Arterial blood samples were taken for determination of plasma concentrations of TNF-α and 1L-6. Results Compared with group S, Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly increased, whereas SOD activity decreased in the other 4 groups ( P < 0.05). Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly decreased, whereas SOD activity increased in group Ipr, Ipo and Ipr + Ipo as compared with group IIR ( P < 0.05). Chiu score and MDA content were significantly lower, whereas SOD activity higher in group Ipr + Ipo than in group Ipr and Ipo ( P < 0.05). No significant differences were detected in the indices between group Ipr and group Ipo ( P > 0.05). Conclusion Ischemic preconditioning-postconditioning can attenuate the intestinal IR injury in rats, and the efficacy is better than that of either Ipr or Ipo alone.     

梯度降压缺氧预激对小鼠心肌缺氧耐受性影响及其初探

目的：探讨反复缺氧预激对小鼠缺氧耐受性的影响及其可能机制。方法：用正常小鼠及经５次梯度降压缺氧预激小鼠分别制备血浆及心肌匀浆。将来自正常小鼠及预激小鼠的血浆分别注入两组正常小鼠腹腔（Ｎｏｎ－ＰＰ组和ＰＰ组），将自来正常小鼠及预激小鼠的心肌匀浆分别注入另两组正常小鼠腹腔（Ｎｏｎ－ＰＨ组ＰＨ组）。各小鼠分别于注射后３０ｍｉｎ置于２８．７ｋＰａ低压所氧环境下测心电活动时间（ＣＥＡＴ）。结果：ＰＨ组ＣＥＡ     

四逆汤对动脉粥样硬化家兔脂代谢及血管内皮功能的影响

目的 观察四逆汤预防性用药对家兔实验性动脉粥样硬化（ＡＳ）脂代谢及血管内皮功能的影响，探讨四逆汤的抗ＡＳ作用及可能机制。方法 运用图象分析法测定主动脉内膜脂质斑块面积百分比，脂代谢各指标分别运用酶动力学法、一步法、公式计算法、免疫透射比浊法等方法测定。血清一氧化氮（ＮＯ）及血浆内皮素（ＥＴ）分别用酶法及放射免疫法检测。结果 四逆汤可明显缩小主动脉内膜脂质愉面积，降低血清总胆固醇旨脂蛋白＝胆固醇、载     

热休克对大鼠缺血-再灌心肌的保护作用探讨

目的：从离体和在体两方面探讨热休克反应对缺血再灌心肌的保护作用。方法：实验采用ＳＤ大鼠，随机分为热休克组和对照组。动物经热休克处理恢复２４ｈ后，离体部分取心进行Ｌａｎｇｅｎｄｏｒｆ灌流，复制缺血３０ｍｉｎ／再灌３０ｍｉｎ的模型，实验中全程记录心电图（ＥＣＧ）及心肌收缩幅度，并测定冠脉流出液的流量变化、肌酸激酶（ＣＫ）活性及丙二醛（ＭＤＡ）含量；在体部分行冠脉左前降支结扎／松绑术复制缺血３０ｍｉｎ／再灌３０ｍｉｎ的模型，实验全程记录ＥＣＧ并测定ＭＤＡ的含量。结果：离体部分热休克组再灌注２、５、１０、１５、２０、３０ｍｉｎ，６个时点心肌收缩幅度及冠脉流量的恢复率显著高于对照组，再灌最初５ｍｉｎ内心律失常的发生率显著低于对照组，再灌３０ｍｉｎ时心肌内ＭＤＡ的含量也显著低于对照组；在体部分热休克组再灌最初５ｍｉｎ内心律失常的发生率及再灌３０ｍｉｎ时心肌内ＭＤＡ的含量均显著低于对照组。结论：热休克反应对大鼠离体与在体的缺血再灌心肌均有一定的保护作用。     

中药防治脑缺血再灌注损伤的研究

现代医学研究认为缺血再灌注损伤是大多数缺血性脑血管病的主要的病理生理过程 ,其发生机制主要有自由基学说、钙超载学说、兴奋性氨基酸学说、花生四烯酸代谢失衡和白细胞损伤作用等。中医将本病归属中风范畴 ,病机为气虚不能帅血 ,或气滞血瘀阻滞脉络所致 ,是临床常见的预后较差的一种疾病 ,因而如何防止脑缺血损伤引起国内外广泛重视。近年来的研究表明 ,许多中药有抗脑缺血再灌注损伤的作用。本文就中药防治脑缺血再灌注的研究状况作一综述。1　清除自由基　人体正常代谢产生的自由基可被体内相应的自由基清除酶如超氧化物歧化酶(ＳＯＤ…     

热休克反应对缺血-再灌心肌保护作用的机制探讨

目的：探讨热休克反应对大鼠缺血-再灌心肌保护作用的可能机制。方法：SD大鼠,随机分为对照组及热休克组,动物经热休克处理恢复2或24h后复制缺血再灌模型并进行各项检测。结果：①热休克处理后心肌组织内SOD活性显著高于对照组,MDA含量则显著低于对照组。②热休克组心肌组织内乳酸及ATP含量均显著高于对照组,糖原含量则显著低于对照组。③热休克反应能诱导HSP70i的转录。结论：热休克反应对缺血-再灌心肌的保护作用与心肌能量代谢的改善、抗氧化能力的增强以及HSP70i的转录合成增强有关。     

保心胶囊对急性心肌缺血犬一氧化氮和内皮素的影响

目的探讨中药复方保心胶囊(四逆汤胶囊)对实验性急性心肌缺血犬一氧化氮(NO)和内皮素-1(ET-1)的影响.方法结扎冠状动脉左前降支建立急性心肌缺血犬模型,在心肌缺血前、缺血后30、60和120min,分别观察犬血清NO和血浆ET-1水平的变化,并测定心肌组织NO和ET-1的含量.结果在犬急性心肌缺血过程中,血清和心肌NO水平明显下降,而血浆和心肌ET-1水平明显增高;在保心胶囊治疗组,血清和心肌的NO水平明显升高,ET-1水平明显降低,与缺血组比较有显著性差异(P＜0.05).结论促进NO的产生和抑制ET-1的合成可能是保心胶囊抗心肌缺血性损伤的重要机制之一.     

离子对萃取—分光光度法测定保心提取液中乌头类生物碱的含量

目的 :测定保心提取液中乌头类生物碱的含量。方法 :采用离子对萃取—分光光度法测定 ,并对标准曲线制备、加样回收率试验、精密度试验、专属性试验、耐用性试验等项目进行了方法学考察。结果 :测定方法线性关系良好 ,平均回收率 99.4 % ,并具有良好的精密度、专属性和耐用性。结论 :该法用于测定保心提取液中乌头类生物碱的含量准确可靠、简便易行、专属性强