三七总皂甙对实验性脑缺血脑血流及血脑屏障的影响作用

目的 观察三七总皂甙对脑缺血后再灌流期间血脑屏障及脑血流的影响。方法 利用大鼠局灶性脑缺血再灌流和全脑缺血再灌流损伤两种实验模型。结果 与相应对照组比较，不论是全脑缺血还是局灶性脑缺血1h后再灌注3d，应用三七总皂甙的各组动物及水肿明显减轻，血脑屏障通透性改善，大脑局部血流量显著增加。结论 三七总皂甙对脑缺血后脑水肿、血脑屏障、大脑局部血流量具有保护作用。     

血必净对大鼠肝缺血-再灌注后急性肺损伤的保护作用

目的观察肝脏缺血-再灌注后急性肺损伤的发病机制及血必净对其的干预作用。方法将健康雄性Wistar大鼠90只随机分3组:假手术组(SOG组)30只,缺血再灌注组(I/R组)30只,血必净组(XBJ组)组30只。XBJ组术前3d经尾静脉注射血必净注射液5ml·kg-1·d-1。于再灌注6h、12h、24h各组分别随机选取10只大鼠进行标本检测:观察大鼠肺脏组织病理切片;取新鲜肺组织测定湿/干重比(W/D)、肺组织髓过氧化物酶(MPO)含量,取动脉血检测血气分析(PaO2)。结果XBJ组较I/R组在相同时相点的肺脏病理改变较轻,MPO含量显著降低(P<0.01);W/D显著降低(P<0.01);PaO2升高(P<0.05)。结论血必净注射液对肝脏缺血-再灌注后急性肺损伤具有保护作用,该作用与抑制中性粒细胞在肺内集聚、减少氧自由基的产生有关。     

姜黄素对大鼠视网膜缺血/再灌注损伤时内质网应激的影响

目的:探讨姜黄素对大鼠视网膜缺血/再灌注损伤(RIRI)时内质网应激(ERS)的影响。方法:选取清洁级SpragueDawley(SD)雄性大鼠96只,采用随机数字表法分为3组(n=32):对照组(C组)、缺血/再灌注组(I/R组)和姜黄素组(CUR组)。I/R组和CUR组采用前房灌注法使眼内压升高而制备大鼠RIRI模型,缺血60 min,再灌注24 h后结束实验。于缺血前60 min时,CUR组腹腔注射姜黄素100 mg/kg,C组和I/R组腹腔注射等容量生理盐水。各组于再灌注24 h时处死8只大鼠,取视网膜组织,光镜下观察病理学改变;采用TUNEL法检测视网膜组织细胞凋亡情况并计算凋亡指数(AI)。3组于再灌注24 h时处死8只大鼠,取视网膜组织,电镜下观察大鼠视网膜组织超微结构改变。3组于再灌注24h时处死8只大鼠,取视网膜组织,逆转录-聚合酶链式反应(RT-PCR)检测大鼠视网膜组织中CCAAT增强子结合蛋白(C/EBP)同源蛋白(CHOP)、活化的转录因子4(ATF4)和X-盒结合蛋白-1(XBP1)mRNA表达。3组于再灌注24 h时处死8只大鼠,取视网膜组织,蛋白免疫印迹法(Western Blot)检测大鼠视网膜组织中、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)及含半胱氨酸的天冬氨酸蛋白水解酶3(caspase-3)的蛋白表达,计算Bcl-2/Bax比值。结果:与C组比较,I/R组大鼠视网膜组织XBP-1、ATF4和CHOP mRNA表达明显上调(P0.05);与I/R组比较,CUR组大鼠视网膜组织XBP-1、ATF4和CHOP mRNA表达明显下调(P0.05)。与C组比较,I/R组大鼠视网膜组织CHOP、Bax和caspase-3蛋白表达升高,Bcl-2蛋白表达及Bcl-2/Bax比值均下降,与C组比较,差异均有统计学意义(P0.05),CUR组大鼠视网膜组织CHOP、Bax和caspase-3蛋白表达下降,Bcl-2蛋白表达及Bcl-2/Bax比值均升高,与I/R组比较,差异均有统计学意义(P0.05)。与C组比较,I/R组大鼠视网膜组织出现形态结构及超微结构损伤,AI值升高(P0.05)。与I/R组比较,CUR组大鼠视网膜组织形态结构及超微结构损伤均减轻,AI值降低(P0.05)。结论:姜黄素可减轻大鼠RIRI,其机制可能与抑制ERS介导的细胞凋亡有关。     

Protective effects of Terminalia arjuna against Doxorubicin-induced cardiotoxicity

Terminalia arjuna has been marked as a potential cardioprotective agent since vedic period. The present study was aimed to investigate the effects of butanolic fraction of Terminalia arjuna bark (TA-05) on Doxorubicin (Dox)-induced cardiotoxicity. Male wistar rats were used as in vivo model for the study. TA-05 was administered orally to Wistar rats at different doses (0.42 mg/kg, 0.85 mg/kg, 1.7 mg/kg, 3.4 mg/kg and 6.8 mg/kg) for 6 days/week for 4 weeks. Thereafter, all the animals except saline and TA-05-treated controls were administered 20 mg/kg Dox intraperitonially. There was a significant decrease in myocardial superoxide dismutase (38.94%) and reduced glutathione (23.84%) in animals treated with Dox. Concurrently marked increase in serum creatine kinase-MB (CKMB) activity (48.11%) as well as increase in extent of lipid peroxidation (2.55-fold) was reported. Co-treatment of TA-05 and Dox resulted in an increase in the cardiac antioxidant enzymes, decrease in serum CKMB levels and reduction in lipid peroxidation as compared to Dox-treated animals. Electron microscopic studies in Dox-treated animals revealed mitochondrial swelling, Z-band disarray, focal dilatation of smooth endoplasmic reticulum (SER) and lipid inclusions, whereas the concurrent administration of TA-05 led to a lesser degree of Dox-induced histological alterations. These findings suggest that butanolic fraction of Terminalia arjuna bark has protective effects against Dox-induced cardiotoxicity and may have potential as a cardioprotective agent.     

大鼠心肌急性缺血再灌注Fos蛋白表达及其意义

目的:探讨急性心肌缺血再灌注早期不同时间心肌细胞内Fos蛋白表达的变化,为心肌早期缺血再灌注损伤致死死后诊断提供新方法。方法:在32只SD大鼠建立心肌早期缺血再灌注损伤模型,另外40只大鼠分为正常与缺血对照组。用免疫组化SABC法结合图象分析研究心肌细胞核Fos蛋白的累积情况。结果:缺血30min再灌注30min后,再灌注区有部分心肌细胞核呈弱阳性着色,以后随缺血时间延长核阳性增强。缺血90min再灌注30min后核棕褐色染色最强,180min后又开始减弱。正常和单纯缺血组心肌细胞核未见有阳性反应。HE染色无明显病理改变。结论:Fos蛋白表达高峰在缺血90～180min之间,FosSABC染色法可诊断缺血30min再灌注30min或更长时间的损伤。免疫组化染色法检测心肌细胞核Fos蛋白的表达有望成为急性心肌缺血再灌注死后诊断的一种有意义的手段。     

Melatonin protects N2a against ischemia/reperfusion injury through autophagy enhancement

Researches have shown that melatonin is neuroprotectant in ischemia/reperfusion-mediated injury.Although melatonin is known as an effective antioxidant,the mechanism of the protection cannot be explained merely by antioxidation.This study was devoted to explore other existing mechanisms by investigating whether melatonin protects ischemia/reperfusion-injured neurons through elevating autophagy,since autophagy has been frequently suggested to play a crucial role in neuron survival.To find it out,an ischemia/...     

PI3K/AKT/Bcl-2通路在吡格列酮保护缺血再灌注损伤心肌细胞中作用的研究

目的 研究吡格列酮对缺血再灌注损伤心肌细胞的保护作用机制中PI3K/AKT/Bcl-2信号通路的作用.方法 取Wistar大鼠乳鼠心室肌细胞进行体外培养,缺氧、复氧各3 h后建立缺血再灌注损伤细胞模型.采用免疫细胞化学染色法检测细胞内Bcl-2蛋白含量,采用Western-bloting检测细胞内Bcl-2蛋白表达水平.结果 免疫细胞化学染色法及Western-bloting结果均显示：与Ⅰ组比较,P组Bcl-2表达明显增加（P〈0.05）;与P组比较,P＋Ly组Bcl-2表达明显减少（P〈0.05）.结论 吡格列酮减轻心肌缺血再灌注损伤保护机制与其激活PI3K/AKT/ Bcl-2信号通路有关.     

多巴酚丁胺负荷核素心肌显像在冠心病诊断中的应用

目的 药物负荷核素心肌显像在冠心病诊断中的价值。方法 选取本院胸痛可疑冠心病，且能耐受平板运动试验的住院患者55例，进行多巴酚丁胺(DBA)负荷99m^Tc-MIBI门控心肌灌注断层显像(SPECT)，平板运动试验检查，部分行冠脉造影检查。结果DBA-SPECT结果40％(22／55)的患者DBA负荷SPECT结果呈可逆性放射性稀疏(即心肌缺血改变)。20例有冠脉造影对照的患者中，DBA负荷SPECT诊断冠心病的灵敏度87．5％(7／8)，特异性75％(9／12)，准确率80％(16／20)。结论DBA负荷SPECT是诊断冠心病的一种敏感性及特异性较高的非创伤性方法。