腺嘌呤核苷酸转运体在缺血-再灌注大鼠心肌中的表达

目的：通过观察大鼠心肌缺血-再灌注模型中腺嘌呤核苷酸转运体(ANT)变化情况，以探讨ANT对心肌的保护作用。方法：将大鼠左冠状动脉前室间(前降)支闭塞20min后，再灌注4h、1天、3天和7天四个时相进行观察，用RT-PCR计算机凝胶成像分析系统检测心肌ANT1、ANT2 mRNA含量。结果：心肌缺血20min，再灌注4h时，ANT1 mRNA达高峰；再灌注1天时，ANT2 mRNA达峰值。两者与对照组相比差异均有显著性意义。结论：心肌缺血-再灌注后，心肌ATP的需求和心肌细胞的凋亡均在24h左右达高峰。     

大鼠脑缺血／再灌注过程中脑型葡萄糖转运体在缺血半影区的表达

【目的】研究大鼠局灶性脑缺血不同缺血时间和不同再灌注时间的脑梗死体积比、皮质半影区脑型葡萄糖转运体（GLUT1、GLUT3）转录水平和蛋白水平的表达。【方法】用线栓法复制大鼠局灶性脑缺血模型，用Kontron IBAS2．5全自动图像分析系统检测脑梗死体积比；剥取缺血半影区皮质组织，采用逆转录-聚合酶链反应（RT-PCR），测定GLUT1、GLUT3 mRNA水平的变化；用免疫组织化学半定量测定GLUT1、GLUT3蛋白水平的变化。【结果】脑缺血1h后再灌注（MCAO1h／R）较缺血3h再灌注（MCAO3h／R）脑梗死体积明显减小。MCAO1h／R组GLUT1、GLUT3 mRNA缺血后升高，24h到达高峰，但GLUT1比GLUT3提前升高，且升高的幅度更大。MCA03h／R组GLUT1在3h开始升高，24h到高峰；GLUT3在缺血3h有一下降点，然后升高，24h到高峰，一周恢复正常，同样GLUT1比GLUT3提前升高，且升高的幅度更大。MCAO3h／R组较MCAO1h／R组的GLUT1、GLUT3峰值低。GLUT1、3蛋白水平的表达与mRNA相符合。【结论】GLUT1、GLUT3在缺血半影区的表达上调，可能是机体对缺血，再灌注损伤的保护性反应。     

大鼠脑缺血/再灌注过程中脑型葡萄糖转运体在缺血半影区的表达

【目的】研究大鼠局灶性脑缺血不同缺血时间和不同再灌注时间的脑梗死体积比、皮质半影区脑型 葡萄糖转运体(GLUT1、GLUT3) 转录水平和蛋白水平的表达。【方法】用线栓法复制大鼠局灶性脑缺血模型, 用 Kontron IBAS2.5 全自动图像分析系统检测脑梗死体积比; 剥取缺血半影区皮质组织, 采用逆转录- 聚合酶链反应 (RT-PCR) , 测定GLUT1、GLUT3 mRNA 水平的变化; 用免疫组织化学半定量测定GLUT1、GLUT3 蛋白水平的变 化。【结果】脑缺血1 h 后再灌注(MCAO1h/R) 较缺血3 h 再灌注(MCAO3h/R) 脑梗死体积明显减小。MCAO1h/R 组GLUT1、GLUT3 mRNA 缺血后升高, 24 h 到达高峰, 但GLUT1 比GLUT3 提前升高, 且升高的幅度更大。 MCAO3h/R 组GLUT1 在3 h 开始升高, 24 h 到高峰; GLUT3 在缺血3 h 有一下降点, 然后升高, 24 h 到高峰, 一 周恢复正常, 同样GLUT1 比GLUT3 提前升高, 且升高的幅度更大。MCAO3h/R 组较MCAO1h/R 组的GLUT1、 GLUT3 峰值低。GLUT1、3 蛋白水平的表达与mRNA 相符合。【结论】GLUT1、GLUT3 在缺血半影区的表达上调, 可 能是机体对缺血/再灌注损伤的保护性反应。     

逐级再灌注对缺血心肌的保护作用

本文旨在探讨膛有再灌注对心肌缺血－再灌注损伤的保护作用。离体豚鼠心工作模型，心脏缺血停搏１２０ｍｉｎ后再灌注６０ｍｉｎ。再灌注时，对照组以５．３９ｋＰａ常规压力行ｌａｎｇｅｎｄｏｒｆｆ灌流１５ｍｉｎ，再转为工作心状态。实验组则在Ｌａｎｇｅｎｄｏｒｆｆ灌注期间，逐级提高灌注压，分别以１．９６、２．９４和５．３９ｋＰａ的压力各灌注５ｍｉｎ。结果显示：探讨性再灌注可减轻心肌超微结构损伤，降低心肌肌酸磷酸     

镁对缺血后再灌注心肌线粒体膜的影响

在大鼠离体等容收缩心脏观察缺血后再灌注对心肌线粒体的损伤及镁的保护作用。结果表明，在缺血期灌注高镁溶液可保护线粒体的谷胱甘肽过氧化物酶活性，减轻脂质过氧化反应，线粒体膜流动性维持较好，钙超载现象明显减轻。     

静脉心肌声学造影观察心肌微血管缺血再灌注损伤的实验研究

为探讨急性心肌缺血再灌注后心肌微血管状态，观察了三条开胸犬关降支阻断前后，心肌声学造影显示的心肌微血管对Ａｃｈ反应情况。结果表明；ＬＡＤ阻断３０ｍｉｎ再开放后，心肌微血管灌注于血流重建后９０ｍｉｎ才恢复。说明心肌微血管内皮损伤是心肌顿抑的原因之一。     

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只大鼠分业怀缺血对照组，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。     

阿托伐他汀对大鼠心肌缺血再灌注的影响及作用机制

目的:探讨阿托伐他汀预处理对大鼠心肌缺血再灌注后的作用及其可能的机制。方法:42只Wistar大鼠随机分为3组:假手术组、缺血再灌注组、阿托伐他汀预处理组;建立大鼠心肌缺血再灌注损伤模型,测定肌酸激酶(CK)水平,Evans b lue、TTC染色后,用计算机图像分析软件计算梗死面积;测定心肌髓过氧化物酶(MPO)、血清白介素-6(IL-6)及白介素-8(IL-8)含量。结果:与缺血再灌注组比较,阿托伐他汀预处理组CK减少,心肌梗死面积显著减小;M PO、IL-6、IL-8显著降低。结论:阿托伐他汀能明显减轻心肌再灌注损伤的发生和发展,其作用机制可能通过抑制炎症因子的合成,减少中性粒细胞的浸润,从而改善心肌缺血再灌注损伤的发生。     

大鼠脑缺血再灌注后GDNF mRNA的表达及人参皂甙Rb1对其的影响

目的:从分子水平探讨大鼠局灶性脑缺血再灌注后的GDNFmRNA表达规律及人参皂甙Rb1对其的影响。方法:阻塞大鼠大脑中动脉2h再灌注3h至10d制备脑缺血模型,通过RT-PCR方法克隆的大鼠GDNFcDNA构建重组腺病毒质粒,并用质粒制备地高辛标记的GDNFcDNA探针,采用原位杂交技术观察脑缺血模型不同时程GDNFmRNA的表达及人参皂甙Rb1对其的影响。结果:GDNFmRNA主要分布于神经细胞的突起,在纤维束处更明显。脑缺血再灌注3h后GDNFmRNA表达出现上调反应,3d达高峰,此后逐渐减弱。人参皂甙Rb1能促进GDNFmRNA的表达。结论:脑缺血再灌注后GDNFmRNA的表达与缺血性损伤有一定的联系,人参皂甙Rb1对中枢神经系统有保护作用。     

地尔硫Zhuo及过氧歧化酶对心肌缺血再灌注损害的保护

对比地尔硫Ｚｈｕｏ及过氧歧化酶（ＳＯＤ）对心肌缺血再灌注损害的保护作用,以及明确联合应用ＳＯＤ＋ＤＴＺ的疗效是否比单一药物更好。方法：将３７只小猪造成在体心肌缺血再灌注模,分为４组。Ⅰ组１０只于再灌注前５分 静脉注射生理盐水作为对照组,Ⅱ组９只再灌注前５分钟静脉注射ＳＯＤ,Ⅲ组８只于再灌注前５分钟静脉注射ＤＴＺ,Ⅳ组９只于再灌注前５分钟静脉注射ＤＴＺ＋ＳＯＤ,结果：（１）心梗范围;用药各组与对照组     

Dynamic expression of glucose transporters 1 and 3 in the brain of diabetic rats with cerebral ischemia reperfusion

Background Blood glucose control improves the outcome of diabetic patients with stroke, but the target range of blood glucose control remains controversial. The functional recruitment of ischemia penumbra is extremely important to the recovery after stroke. The present study aimed to explore the expression of brain-type glucose transporters （GLUT1 and GLUT3） in cerebral ischemic penumbra at different blood glucose levels and different ischemic-reperfusion time in diabetic hypoxia-ischemia rats. The results might provide an experimental basis for clinical treatment of diabetic patients with stroke. Methods The Wistar rats included in this study were randomly assigned to 4 groups （50 rats each）： normal control group （NC）, uncontrolled diabetic group （DM1）, poorly-controlled diabetic group （DM2）, and well-controlled diabetic group （DM3）. Diabetic rats were induced by single intraperitoneal injection of streptozotocin, and the focal ischemic rat model of middle artery occlusion （MCAO） was made by insertion of fishing thread in 6 weeks after the establishment of the diabetic model. Each group was divided into 5 subgroups （10 rats each）： four focal ischemic subgroups at different ischemic-reperfusion time （at 3,12, 24 and 72 hours after reperfusion, respectively） and one sham-operated subgroup. The mRNA and protein expression of GLUT1 and GLUT3 was assessed by RT-PCR and Western blotting, respectively. Results There was significant difference in the mRNA expression of GLUT1 and GLUT3 between the four focal ischemic subgroups and the sham-operated subgroup at different reperfusion time in each group. The mRNA expression of GLUT1 and GLUT3 in the 4 ischemic groups began to increase at 3 hours, peaked at 24 hours after reperfusion and maintained at a higher level even at 72 hours compared with that of the sham-operated subgroup. The mRNA expression of GLUT1 increased more significantly than that of GLUT3. The mRNA expression of GLUT1 and GLUT3 was significantly different between the diabetic groups and normal control group. The mRNA expression of GLUT1 and GLUT3 was increased more significantty in the diabetic groups than that in the normal control group. There was a significant difference in the mRNA expression in the groups with different blood glucose levels. The mRNA expression tended to decrease with increased blood glucose levels. The expression trend of GLUT1 and GLUT3 protein was similar to that of GLUT1 and GLUT3 mRNA. Conclusions GLUT1 and GLUT3 expression was notably up-regulated in the penumbra region after cerebral ischemia in this study. But the up-regulated amplitude of GLUT1 and GLUT3 in the diabetic rats with cerebral ischemic injury became smaller than that of the normal controls. In the treatment of diabetic patients with cerebral embolism, blood glucose control should not be too strict, otherwise the up-regulation of GLUT1 and GLUT3 induced by cerebral ischemic injury might not be able to meet the needs of energy metabolism in cells. Chin Med J 2009; 122（ 17）： 1996-2001     

心肌缺血-再灌注损伤的超微结构变化

目的：观察犬急性心肌缺血－再灌注损伤的早期超微结构改变,探讨急性心肌缺血－再灌注损伤所致急死的形态学基础。方法：复制犬急性心肌缺血－再灌注损伤动物模型,在透射电镜下观察心肌纤维、线粒体、内质网和微血管结构变化。结果：缺血30min再灌注120min,心肌细胞线粒体轻度肿胀,基质内可见絮状致密体;缺血60～90min再灌注120min,心肌细胞线粒体嵴断裂,基质内出现絮状致密体和颗粒状致密体。微血管内皮细胞肿胀,血管腔狭窄。结论：再灌注可使缺血30min心肌超微结构得到部分恢复,加重缺血60～90min心肌超微结构改变。     

利多卡因减轻家兔心肌缺血-再灌注炎性损伤的研究

目的研究利多卡因的抗炎作用对心肌缺血-再灌注损伤的保护作用。方法 18只家兔随机分为3组(每组6只),假手术组、缺血-再灌注组和利多卡因组。监测家兔左室内压峰值(LVSP)、±dp/dtmax,测定血浆IL-6的水平,光镜观察心肌损伤及中性粒细胞的浸润程度。结果与缺血-再灌注组比较,利多卡因组LVSP及±dp/dtmax再灌注后的恢复率均高于缺血-再灌注组(P<0.01),血浆IL-6浓度明显低于缺血-再灌注组(P<0.01),心肌损伤及中性粒细胞浸润程度较轻。结论利多卡因可以提高心功能,抑制炎症反应,减轻家兔心肌缺血-再灌注损伤。     

米诺环素预处理对大鼠心肌缺血再灌注损伤和HMGB1表达的影响

目的:探讨米诺环素预处理对大鼠心肌缺血再灌注损伤的保护作用及其可能的机制。方法:成年雄性SD大鼠缺血前1h给予米诺环素(45mg/kg,ip),结扎冠脉前降支缺血30min后,恢复灌注4h;应用2,3,5-氯化三苯基四氮(TTC)法检测心肌梗死面积;试剂盒检测乳酸脱氢酶(LDH)、肌酸激酶(CK)、丙二醛(MDA)和超氧化物歧化酶(SOD);采用原位脱氧糖核苷酸末端转移酶介导的缺口末端标记(TUNEL)法检测心肌细胞的凋亡;Western blot检测高迁移率族蛋B1(HMGB1)表达。结果:与对照组相比,米诺环素预处理显著减小了心肌梗死面积,降低了心肌细胞凋亡和LDH、CK等血清心肌坏死标记物的表达(P<0.05)。米诺环素预处理也显著降低了MDA的表达,抑制了SOD的减少(P<0.05)。同时,米诺环素预处理抑制了缺血再灌注引起的HMGB1的表达(P<0.05)。结论:米诺环素预处理能够减轻心肌缺血再灌注损伤并抑制心肌细胞凋亡,这种保护作用可能与其抑制缺血再灌注诱导的HMGB1的表达有关。     

缺血预处理与心肌缺血/再灌注细胞凋亡及NF-κB表达的关系

目的:研究缺血预处理对心肌缺血/再灌注细胞凋亡及NF-κB表达的影响。方法:健康SD大鼠30只随机分为3组:对照组,缺血/再灌注组,缺血预处理组,每组10只。利用心肌缺血/再灌注模型,采用原位末端标记(TUNEL)法测定凋亡细胞,采用W estern-b lot法测定NF-κB的表达。结果:缺血再灌注组心肌细胞的凋亡百分数和NF-κB的表达均显著增加,与对照组相比有显著差异;而缺血预处理组与缺血/再灌注组相比,其凋亡心肌细胞百分数和NF-κB的表达均显著减少。结论:缺血预处理抑制心肌细胞的凋亡的作用机制与其抑制NF-κB的表达有关。     

七氟烷后处理对大鼠在体心肌缺血再灌注时心肌细胞凋亡的影响

目的研究七氟烷（sevoflurane）后处理对大鼠在体心肌缺血再灌注损伤后细胞凋亡的影响。方法 SD雄性大鼠60只,随机分为5组（n=12）：假手术组（P组）、缺血再灌注组（ischemia-reperfusion,IR组）,小、中、大剂量组（S1、S2、S3组）,建立心肌缺血再灌注模型。光镜下观察各组心肌组织病理变化,检测心肌细胞中Bax、Bcl-2蛋白含量、心肌细胞凋亡指数（AI）。结果与P组相比,IR组、各S组心肌Bax与Bcl-2、AI均显著升高（P〈0.05）,Bcl-2/Bax显著降低（P〈0.05）;与IR组相比,各S组Bax与AI均显著降低（P〈0.05）,Bcl-2与Bcl-2/Bax均显著升高（P〈0.05）;S1组与S3组各指标间无明显差异（P〉0.05）;与S1、S3组相比,S2组Bax与AI均显著降低（P〈0.05）,Bcl-2与Bcl-2/Bax均显著升高（P〈0.05）。结论七氟烷后处理可通过调节Bax与Bcl-2的表达,提高Bcl-2/Bax来发挥心肌保护作用,且中剂量组效果更明显。     

Protective effects of Yindanxinnaotong capsule in a rat model of myocardial ischemia/reperfusion injury

ObjectiveTo investigate the effects of Yindanxinnaotong capsule (YDXNTC) and main components compatibility and ratios on myocardium against ischemia/reperfusion injury and the effect's underlying mechanism.MethodsMyocardial ischemia/reperfusion injury (MIRI) was induced by ischemia for 30 min and reperfusion for 30 min. Electrocardiogram data and coronary flow were recorded, and superoxide dismutase (SOD), malondialdehyde (MDA), lactate dehydrogenase, creatine kinase-MB, cardiac troponin T and I (cTnT, cTnI) and interleukin-1β, interleukin-8, interleukin-18 (IL-1β, IL-8, IL-18) in myocardium were measured. Hypoxia/reoxygenation and hydrogen peroxide (H₂O₂) injury were induced by hypoxia for 3 h/reoxygenation for 2 h, and 100 μM H₂O₂ for 1 h, respectively, in vitro rat myocardial cells (H9c2). Cell viability, SOD, MDA, cTnT and inflammatory factors (IL-1β, IL-8 and IL-18) were determined, and Toll-like receptor 4 (TLR-4) expression was measured by western blotting.ResultsIn the isolated heart experiment, elevated heart function, coronary flow and SOD levels, and decreased MDA levels and inflammatory factors were noted in the YDXNTC, main components and main components compatibility groups. Ventricular tachycardia/ventricular fibrillation occurrence decreased in the ginkgo biloba extract (GBE), and GBE and salvia miltiorrhiza ethanol extract compatibility (SM-E, GSEC) groups. Lactic dehydrogenase levels decreased in the YDXNTC and aqueous extract of salvia miltiorrhiza (SM-H) groups. Creatine kinase-MB decreased with GBE, SM-E, SM-H and GSEC treatment, and cTnI and cTnT levels decreased with GSEC. In the in vitro cell study, YDXNTC and main components ratios improved cell viability and SOD levels, and suppressed MDA, cTnT and inflammatory factors. TLR-4 expression was down-regulated.ConclusionYDXNTC and main components compatibility showed protective effects on MIRI in this rat model and in vitro study. Regulating the Toll-like receptor signaling pathway may affect the mechanism.