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1.
目的:探讨一氧化氮(NO)对大鼠LI/R后肾脏P-选择素表达的影响及意义。方法:采用本室常规方法复制大鼠LI/R模型。将大鼠随机分为四组:对照组,LI/R组,L—Arg组和L-NAME组。观察肢体缺血4h再灌注4h后各组动物血浆NO及肌酐(Cr)、尿素氮(BUN)的变化;观察肾组织NO、髓过氧化物酶(MPO)、总一氧化氮合酶(tNOS)、诱导型一氧化氮合酶(iNOS)、结构型一氧化氮合酶(cNOS)的改变;测定尿蛋白含量、利用聚丙烯酰胺凝胶电泳法检测尿蛋白性质;免疫组织化学方法检测肾组织P-选择素(P—selectin)的蛋白表达,结合自动图象分析系统对其结果进行定量分析;肾组织切片经六氨银染色在光镜下观察其形态学改变。结果:与control组比较.LI/R组大鼠血浆NO、BUN、Cr均明显升高;肾组织MPO、NO、tNOS、iNOS均明显增加,而cNOS明显下降;尿蛋白含量增多,电泳显示,有大分子量蛋白排出;光镜下可见肾小管上皮细胞水肿,有炎细胞浸润:免疫组化结果显示:P-selectin蛋白表达明显较control组增强。与LI/R组相比,L-Arg组各项损伤指标明显减轻;肾组织P—selectin蛋白表达明显减弱;L-NAME组血浆和肾组织各项损伤指标明显加重;肾组织P—selectin蛋白表达明显增加。结论:大鼠LI/R后急性肾损伤的发生可能与P—selectin的表达有关;NO可能通过减弱P-selectin的表达及中性粒细胞的浸润,减轻LI/R后肾脏组织形态学及肾功能的损伤性变化。  相似文献   

2.
目的:研究阿托伐他汀预处理对心肌缺血再灌注损伤大鼠心室重构、炎症反应和氧化应激的影响.方法:选取90只SD级大鼠进行研究,将其随机分成假手术组、缺血再灌注组、阿托伐他汀组,每组30只.假手术组与缺血再灌注组大鼠予以生理盐水(5 mL/d)连续灌胃7d处理,阿托伐他汀组予以阿托伐他汀20 mg/(kg-d)连续灌胃7 d...  相似文献   

3.
摘要 目的:探究低温治疗对大鼠心肌缺血模型再灌注后组织无复流的相关影响。方法:选择标准成年Sprague Dawley大鼠40只(雄性雌性各20只),平均体重(205.6±1.5)g,随机分为对照组和观察组,每组各20只,建立心肌缺血再灌注模型,对照组给予常温处理,观察组则在再灌注结束时晚期给予低温干预,对两组大鼠心肌组织无复流的差异及相关变量进行比较分析。结果:观察组的心肌缺血高危区域所占的百分比平均水平为(16.7±3.5)%,低于对照组的(35.6±2.5)%(P<0.05);观察组的组织坏死区域所占的百分比平均水平为(23.8±5.1)%,低于对照组的(56.4±3.9)%(P<0.05)。与对照组相比,观察组再灌注结束时心率降低,收缩压和平均血压升高(P<0.05);两组大鼠心肌染色宏观评价显示心肌梗死面积无明显差异,但观察组无复流的区域小于对照组。结论:在大鼠心肌缺血动物模型中通过再灌注后晚期给予治疗性的低温处理能够显著改善微血管的堵塞,并且此效应与心肌梗死的面积无关。  相似文献   

4.
目的探讨缺血预处理(IPC)对兔脊髓缺血再灌注损伤后水通道蛋白-4(AQP-4)表达的影响。方法日本大耳白兔72只,随机分为3组:假手术组(S组)、脊髓缺血再灌注损伤组(I/R组)和缺血预处理组(IPC组)。I/R组和IPC组阻断腹主动脉30min造成脊髓缺血再灌注损伤,IPC组在损伤前短暂阻断腹主动脉5min二次实施预处理,S组暴露肾动脉下腹主动脉但不阻断。分别于再灌注损伤后4h和24h进行神经功能评分,并取L4—6脊髓缺血节段,计算脊髓组织含水量,免疫组化法测定脊髓组织中AQP-4表达水平。结果与S组比较,I/R组神经运动功能评分降低,脊髓组织含水量增加,AQP-4表达增加(P〈0.05)。与I/R组比较,IPC组神经运动功能评分增高,脊髓组织含水量降低,AQP-4表达减少(P〈0.05)。结论IPC可抑制脊髓损伤后AQP-4的表达,进而减轻脊髓水肿,保护缺血再灌注损伤的脊髓。  相似文献   

5.
探讨缺血后处理对兔脊髓缺血再灌注微循环损伤的影响.成年新西兰大白兔24只随机分为假手术组(C组),缺血再灌注损伤组(IR组),缺血后处理组(P组).IR组和P组采用Zivin改进法制备脊髓缺血再灌注模型,P组在缺血30 min后行复灌1 min/缺血1 min相同处理3次.采用激光多普勒检测缺血前,缺血时及再灌注各时点血流量值,在再灌注24 h时取兔脊髓组织作HE染色观察病理形态学,比色法检测脊髓组织一氧化氮(Nitric oxide,NO)的含量,放免法检测内皮素-1(Endothelin-1,ET-1)及免疫组化法检测血红素氧合酶(Hemeoxygenase-1,HO-1)的表达.研究发现与缺血前基础值相比,再灌注10 min时IR组与P组血流量均有增高,在再灌注30、60、120 min,IR组血流量值有不同程度的降低;与IR组相比,P组血流量值在再灌注各时点均有不同程度的增高.与IR组相比,P组NO含量与HO-1表达均有增加,ET-1含量明显减少,NO/ET-1显著高于IR组(P<0.05或0.01),且P组脊髓病理学损伤轻于IR组.结果表明缺血后处理可减轻兔脊髓缺血再灌注微循环损伤,改善脊髓血流量,...  相似文献   

6.
目的:观察心肌核因子-κB(NF-κB)在急性心肌梗死(AMI)再灌注后无复流的活化情况,探讨NF-κB促进无复流发生发展的作用机制。方法:24只新西兰大白兔随机分为假手术组(冠状动脉只穿线不结扎)和缺血再灌注组(结扎冠状动脉2小时,再灌注1小时),每组12只。采用凝胶阻滞迁移分析方法(EMSA)检测正常区、缺血区和无复流区心肌组织中NF-κB活性;ELISA法测定不同时点血浆中白细胞介素-6(IL-6)、超敏C反应蛋白(CRP)以及肿瘤坏死因子-α(TNF-α)的含量;光镜、电镜观察心肌组织病理变化。结果:(1)与正常区相比,缺血区和无复流区心肌组织中NF-κB活性异常升高(P〈0.01)。(2)与结扎前相比结扎后2h、再灌注后1h血浆IL-6、CRP、TNF-α水平呈进行性升高(P均〈0.05)。(3)NF-κB的活性与无复流面积、血浆IL-6、CRP以及TNF-α水平呈正相关(分别为r=0.844,P〈0.01;r=0.682,P〈0.05;r=0.687,P〈0.05;r=0.893,P〈0.01)。(4)无复流面积与血浆IL-6、CRP以及TNF-α水平呈正相关(分别为r=0.861,P〈0.01;r=0.806,P〈0.01;r=0.877,P〈0.01)。(5)光镜及电镜结果显示无复流区的心肌组织损伤较缺血区更为严重。结论:急性心肌梗死再灌注后无复流现象的发生可能与局部心肌组织中NF-κB的过度活化有关,活化的NF-κB通过促进IL-6、TNF-α等炎症因子的表达,参与无复流的发生发展过程。  相似文献   

7.
NF-κB激活在兔急性心肌梗死再灌注后无复流中的意义   总被引:1,自引:0,他引:1  
目的:观察心肌核因子-κB(NF-κB)在急性心肌梗死(AMI)再灌注后无复流的活化情况,探讨NF-κB促进无复流发生发展的作用机制。方法:24只新西兰大白兔随机分为假手术组(冠状动脉只穿线不结扎)和缺血再灌注组(结扎冠状动脉2小时,再灌注1小时),每组12只。采用凝胶阻滞迁移分析方法(EMSA)检测正常区、缺血区和无复流区心肌组织中NF-κB活性;ELISA法测定不同时点血浆中白细胞介素-6(IL-6)、超敏C反应蛋白(CRP)以及肿瘤坏死因子-α(TNF-α)的含量;光镜、电镜观察心肌组织病理变化。结果:(1)与正常区相比,缺血区和无复流区心肌组织中NF-κB活性异常升高(P<0.01)。(2)与结扎前相比结扎后2h、再灌注后1h血浆IL-6、CRP、TNF-α水平呈进行性升高(P均<0.05)。(3)NF-κB的活性与无复流面积、血浆IL-6、CRP以及TNF-α水平呈正相关(分别为r=0.844,P<0.01;r=0.682,P<0.05;r=0.687,P<0.05;r=0.893,P<0.01)。(4)无复流面积与血浆IL-6、CRP以及TNF-α水平呈正相关(分别为r=0.861,P<0.01;...  相似文献   

8.
目的:通过检测血清TNF-α,IL-6的变化,评价乌司他丁对小肠缺血再灌注损伤的保护作用及机制。方法i健康Wistar大鼠84只,通过夹闭肠系膜上动脉(SMA)60min制作肠缺血模型,随机分成假手术组(C),肠缺血再灌注组(I),UTI治疗组(u)。根据缺血后再灌注时间不同又将I组和U组分成0min、2h和6h组。I组、U组于手术前经尾静脉分别注入生理盐水2mL、乌司他丁5×10^4U/kg,假手术组仅分离SMA,不夹闭血管。于各时点取腹主动脉血测定血清TNF-α、IL-6含量。结果:肠缺血再灌注各时相点均引起血清TNF-α、IL-6的变化,与假手术组相比,各时点TNF-α值显著升高(P〈0.01),IL-6显著升高(P〈0.01)。u组0min、2h血清TNF-α值低于相应时点的I组(P〈0.01);U组0min、2h、6h血清IL-6值低于相应时点的I组(P〈0.05)。结论:乌司他丁可减轻小肠缺血再灌注后的炎症反应。  相似文献   

9.
摘要 目的:探讨阿托伐他汀钙片治疗脑梗死的疗效及其对基质金属蛋白酶(MMP-2)表达的影响。方法:选择2019年5月-2021年2月在本院诊治的脑梗死患者64例,根据随机信封抽签原则将患者分为阿托伐他汀组32例与对照组32例。对照组给予常规双抗治疗,阿托伐他汀组以对照组为基础给予阿托伐他汀治疗,两组都治疗观察3个月,记录MMP-2表达的变化。结果:治疗后阿托伐他汀组的总有效率为93.8 %,高于对照组的68.8 %(P<0.05)。两组治疗后的低密度脂蛋白胆固醇(LDL-C)、甘油三酯(TG)、总胆固醇(TC)水平均低于治疗前(P<0.05),高密度脂蛋白胆固醇(HDL-C)水平高于治疗前(P<0.05),组间对比无差异(P>0.05)。两组治疗后的大脑中动脉平均血流速度(Vm)明显高于治疗前,搏动指数(PI)明显低于治疗前,阿托伐他汀组与对照组对比差异明显(P<0.05)。两组治疗后的血清MMP-2含量低于治疗前,阿托伐他汀组低于对照组(P<0.05)。两组治疗期间的不良反应主要为恶心呕吐、低血压、静脉血栓、头晕脑胀,组内对比无差异(P>0.05)。结论:阿托伐他汀治疗脑梗死能降低MMP-2水平,可在平衡血脂水平的基础上提高患者的治疗效果,还可提高大脑中动脉的血流速度,且为增加不良反应。  相似文献   

10.
目的 评价细胞外信号调节激酶 (ERK)传导通路对低压灌注缺血后处理兔缺血/再灌注损伤脊髓的保护作用及机制.方法 84只日本大耳白兔随机分为7组,分别为C组(对照组,不给予缺血后处理)、PB组(缺血后处理组)、D、PD1、PD3、PD9组分别于腹主动脉开放前1min鞘内注射DMSO 20μl、PD98059 1μg(20μl)、PD98059 3μg(20μl)、PD98059 9μg(20μl)之后进行缺血后处理及PD组(腹主动脉开放前1min鞘内注射PD98059 3μg(20μl),之后不行缺血后处理).分别于再灌注1、3、7、28d时采用Tarlov评分评价后肢运动功能.每组于再灌注1d时处死6只动物,取L3~5节段脊髓组织,采用Western blot技术测定p-ERK1/2 及Bcl-2,Bax蛋白表达.结果 1、3、7、28d,PB组Tarlov评分明显高于其它各组(P<0.05),缺血后处理可以明显上调p-ERK1/2及凋亡抑制基因Bcl-2的表达,下调凋亡促进基因Bax的表达(P<0.05),而这些调节作用可以被ERK1/2阻断剂PD98059抑制.结论 p-ERK1/2在低压灌注缺血后处理对缺血再灌注损伤脊髓的保护中起重要作用.  相似文献   

11.
This study was undertaken to evaluate the post-operative (post-OP) course of rabbits in a surgical model of myocardial infarction (MI). Ten New Zealand White rabbits were subjected to coronary artery ligation after lateral thoracotomy. Anesthesia was delivered using a xylazine-ketamine-isoflurane protocol after endotracheal intubation. Among other cardiorespiratory parameters, arterial pressure was monitored via central ear artery catheterization. Post-OP care included oxygen, antibiotic and analgesic treatment as well as nutritional and fluid support. A series of cardiorespiratory, hematological, blood biochemical and clinical parameters were assessed during the first 21 days. The mortality rate was 10%. Hypotension and hypothermia, noted during the operation, reverted within the first few post-MI hours. Electrocardiographic alterations, which included ST segment elevation and Q wave, appeared after MI and remained throughout the study period. Tachycardia was observed during the first 5 days. Hematological examination revealed mild and transient anemia during the post-OP period and leucocytosis up to the 5th day. Urea was increased up to the 12th post-MI hour while increased AST, ALT, LDH and CK levels normalized by the first 4-5 days. Although the post-OP anorexia period lasted around 5 days, the animals did not manage to regain their body weight by the end of the study period. In conclusion, the present model offers a low mortality rate and could be useful in mid- or long-term MI studies. The animals go through a critical post-OP period of around 5 days during which special care should be given. After that time, their clinical and blood laboratory parameters tend to normalize.  相似文献   

12.
Interleukin-6 (IL-6) is an inflammatory cytokine whose levels increase significantly during myocardial infarction (MI).It has been hypothesised that the concentrations of IL-6 at admission may be useful in prognosticating long-term outcomes. It is unclear, however, whether IL-6 could improve the prognosis of early mortality in MI.We have compared serum IL-6 levels and analysed the disease course in 158 patients with ST-elevation MI (STEMI) who either survived (n?=?148) or died (n?=?10) within 30 days following the admission. Patients were treated in a single university centre with primary percutaneous coronary intervention (PCI).The non-survivors (6.3%) displayed most of typical risk factors for poor outcome. In addition they had significantly higher concentrations of IL-6 at hospital admission (median values 8.5 vs. 2.0 pg/ml; p?=?0.038). However, they were also significantly older than the survivors (median values 72 vs. 57 years; p?=?0.0001). IL-6 levels are known to increase with age and we could confirm a significant correlation between patients’ calendar age and circulating IL-6 (p?=?0.009). Regression analysis revealed that IL-6 concentrations were significantly affected by patients’ age but they did not independently relate to patients’ outcome.Such results indicate that circulating IL-6 at admission may be of limited value in predicting early mortality in STEMI. It is important to recognize that, because of the small group of patients who died (N?=?10), the results must be interpreted with caution. Therefore, we stress that these results should be viewed as preliminary and further validated in a larger set of patients.  相似文献   

13.
Despite early recanalization of an occluded infarct artery, tissue reperfusion remains impaired in more than one-third of the acute myocardial infarction (AMI) patients owing to a process of reperfusion injury. The role of systemic inflammation in triggering this phenomenon is unknown. Proinflammatory factors (hs-CRP, TNF-alpha ) and anti-inflammatory mediators (IL-1 receptor antagonist, IL-10) were measured in 65 patients during the acute phase of a myocardial infarction as well as in 11 healthy control subjects. Myocardial reperfusion injury was defined as the presence of persistent ST-segment elevation despite successful coronary intervention (> or = 50 of the initial value) and was observed in 28 patients. Systemic proinflammatory mediators (particularly hs-CRP and leukocytes) were higher in AMI patients compared to control subjects. Within the group of AMI patients, only serum TNF-alpha differed significantly between patients with versus without reperfusion injury: a median value of 25 versus 13 pg/mL was observed, respectively. Logistic regression analysis identified a high level of TNF-alpha as the most important independent determinant of reperfusion injury (P = .001), beyond total ischemic time (P = .01) and extent of jeopardized myocardium (P = .08). There was no correlation between the TNF-alpha level and the total ischemic time (P = .8) or the extent of jeopardized myocardium (P = .6). Systemic inflammation, in particular high levels of TNF-alpha , is strongly associated with the occurrence of reperfusion injury after successful recanalization. Our findings suggest that TNF-alpha is involved in the triggering and/or amplification of local inflammatory responses related to ischemia-reperfusion injury.  相似文献   

14.
目的:探讨在体情况下,骨骼肌缺血后处理对兔缺血/再灌注心肌坏死和凋亡的影响。方法:新西兰大白兔36只,随机分成3组(每组随机选取6只进行梗死范围的测定,另外6只进行凋亡测定):①假手术组(Sham组);②缺血/再灌注组(I/R组);③远端后处理组(RPostC组)。在缺血前、后及再灌注60 min、120 min分别抽血测定肌酸激酶(CK),乳酸脱氢酶(LDH)的活性。采用伊文思兰(evans blue)和三苯基氯化四氮唑(TTC)染色方法确定心肌缺血区范围以及心肌坏死区范围。用Tunel法检测兔心肌缺血区细胞凋亡情况,免疫组织化学方法检测心肌缺血区蛋白caspase-3、Bcl-2及Bax的表达。结果:RPostC组心肌坏死程度、再灌注末CK活性较I/R组明显减低。RPostC组缺血区心肌Tunel阳性指数显著低于I/R组(21.79%±1.07%vs35.81%±1.10%,P<0.05)。而RPostC组缺血区心肌细胞caspase-3阳性指数显著低于I/R组(25.03%±1.16%vs39%±2.43%,P<0.05)。与Sham组比较,I/R组及RPostC组Bax蛋白表达指数、Bcl-2蛋白表达指数均升高;但RPostC组的Bax/Bcl-2比值降低,而I/R组的Bax/Bcl-2比值升高。与I/R组相比较,RPostC组Bax蛋白表达指数及Bax/Bcl-2比值显著降低,Bcl-2表达指数显著升高,差异均有统计学意义。结论:远端后处理能够明显的减少缺血/再灌注心肌细胞的坏死和凋亡,其减轻心肌细胞凋亡的机制可能与抑制促凋亡基因caspase-3的活化及Bcl-2表达的上调有关。  相似文献   

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16.
The design of targeted ultrasound contrast agents for molecular imaging of myocardial ischemia–reperfusion (IR) requires the availablity of an adequate in vivo model in a species in which cross reactivity with the target occurs. P-selectin (Psel) is an activation-dependent endothelial receptor that supports rapid and reversible cell adhesion in a flowing system. Together with E- and L-selectins it constitutes the selectin family of adhesion molecules. We investigated the myocardial expression of selectins in a closed chest minimally invasive monkey myocardial IR model. Catheter-based occlusion (30–50 min) followed by reperfusion (3 or 5 h) of left anterior descending artery (LAD) was performed in anesthetised monkeys. At the end of each procedure animals were killed, and their hearts were excised. The tissues were analyzed immunohistochemically using an anti-human Psel antibody (AK-6 clone) that cross reacts with rhesus monkey. Histopathological features confirm the presence of IR injuries in myocardial tissues. There was significant increase in the Psel expression in vessels from the IR areas. However, significantly higher Psel immunoreactivity was also seen in areas which are distant from IR injuries.  相似文献   

17.
Shen W  Shi HM  Fan WH  Luo XP  Jin B  Li Y 《Molecular biology reports》2011,38(6):3821-3828
Statins have shown pleiotropic effects, many of them independent of their impact on lipids. Angiogenesis can be beneficial in the acute myocardial infarction to improve circulation. However, it also can be harmful due to worsening of atherosclerosis. Here, we established a new minimal invasive rabbit model to study ischemic myocardium and atherosclerosis together to mimic clinical scenario. We demonstrated that simvastatin has the effect of pro-angiogenesis and further improve cardiac function in ischemic myocardium, as well as the effect of anti-angiogenesis to improve atherosclerosis in aorta vessels.  相似文献   

18.
Salobir B  Sabovic M 《Cytokine》2004,25(6):265-272
The level of interleukin-6 (IL-6), a cytokine with prothrombotic properties, and its associations with metabolic, coagulation and fibrinolytic parameters were investigated in 68 young women (23-49 years, mean 40 years old) six months to six years after myocardial infarction (MI, N=22), lacunar cerebral infarction (LACI, N=16) and deep vein thrombosis (VT, N=30); all women were in the reproductive period, aged <45 years at the time of acute thrombotic event. Forty-seven age-matched women comprised a control group. Basic and multivariate analysis disclosed different patterns of IL-6 increase in all three groups of patients. In the MI group IL-6 was significantly elevated independently of factors known to increase IL-6 levels; the increase was most pronounced in patients with high lipoprotein(a). This result suggests a prothrombotic association of lipoprotein(a) with IL-6. In the whole LACI group IL-6 was not significantly increased. However, patients with elevated levels of IL-6 had abdominal obesity and elevated fibrinogen, suggesting the possibility that this combination might represent a specific risk profile. In VT group elevated IL-6 level was found in the group of previous users of oral contraceptives (OC). This might be relevant, since it is known that OC could importantly increase (previously elevated) IL-6 level in selected women. Our results suggest the hypothesis that the role of IL-6 might be vascular-bed-specific and further propose that increased IL-6 level might represent a novel, non-classical risk factor for development of MI, LACI and VT in specific subgroups of young women, which have to be clarified in further studies.  相似文献   

19.
AIMS: Atherosclerosis is a chronic disease that, from its origin to its ultimate complications, involves inflammatory cells, inflammatory proteins, and inflammatory responses from vascular cells. It has been demonstrated that cytokine activities are under neuroendocrine control, in part exerted by the pineal gland through the circadian secretion of its main product melatonin. Melatonin is mainly released during the night, but the precise relationship between melatonin and the light/dark rhythm of interleukin-6 in patients with acute myocardial infarction is still unclear. METHODS AND RESULTS: The study included 60 patients diagnosed with acute myocardial infarction and 60 healthy volunteers whose venous blood samples were collected at 09:00 h (light period) and 02:00 h (dark period). Our results demonstrate that interleukin-6 concentrations presented a light/dark pattern with mean serum concentrations being higher in the acute myocardial infarction group than in the control group (101.26 +/- 13.43 and 52.67 +/- 7.73 pg/ml at 02:00 h, 41.93 +/- 5.90 and 22.98 +/- 4.49 pg/ml at 09:00 h, respectively, p < 0.05). Differences in the day/night changes in melatonin levels in control subjects (48.19 +/- 7.82 at 02:00 h, 14.51+/- 2.36 at 09:00 h, pg/ml) and acute myocardial infarction patients (25.97 +/- 3.90 at 02:00 h, 12.29 +/- 4.01 at 09:00 h, pg/ml) (p < 0.05) were a result of a reduced nocturnal elevation of melatonin in the acute myocardial infarction group. CONCLUSIONS: The current findings suggest that the circadian secretion of melatonin may be responsible at least in part for light/dark variations of endogenous interleukin-6 production in patients with acute myocardial infarction. In this study, the melatonin seems to have an anti-inflammatory effect.  相似文献   

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