依普利酮对AMI大鼠心肌炎症反应及心脏功能影响的研究

【摘要】 目的 观察依普利酮对急性心肌梗死（AMI）大鼠心肌炎症反应、心脏功能的影响。方法 将结扎左冠状动脉致AMI大鼠模型随机分为AMI组（n=11）和依普利酮治疗组（AMI-E，n=11），并设立假手术（Sham，n=14）组大鼠。在依普利酮（30 mg·kg-1·d-1）治疗4周后，用超声心动图和血流动力学指标评价心脏功能；心肌Masson染色法测定心肌胶原容积分数（CVF）和血管周围胶原面积（PVCA），碱水解法测定羟脯氨酸（Hyp）含量；酶联免疫吸附法测定心肌组织中肿瘤坏死因子-α（TNF-α），白介素-1β（IL-1β）、白介素-6（IL-6）。结果 ①AMI组大鼠心肌CVF、PVCA、Hyp较Sham组显著增加（P＜0.01）；AMI-E组大鼠心肌CVF、PVCA、Hyp较AMI组均显著减低（P＜0.05）。②AMI组大鼠心肌组织中TNF-α(10.7±3.2pg/g)、IL-1β(14.5±3.5pg/g)、IL-6(21.1±8.0pg/g)表达较Sham组[(5.6±1.1pg/g)、 (8.2±2.1pg/g)、 (9.8±3.1pg/g)]显著增加（P＜0.01）；AMI-E组TNF-α(7.8±2.6pg/g)、IL-1β(11.3±3.2pg/g)、IL-6(14.7±4.7pg/g)表达较AMI组显著减轻（P＜0.05），并伴随心脏功能的改善（P＜0.05）。结论 依普利酮改善AMI大鼠心脏功能，可能与抑制心肌炎症反应、减轻心肌纤维化有关。     

培哚普利对肾性高血压大鼠心肌纤维化及转化生长因子β1的影响

目的探讨培哚普利对肾性高血压大鼠心肌纤维化作用及对转化生长因子-β1表达影响。方法建立双肾一夹肾血管性高血压(2K1C)大鼠模型,将24只实验大鼠随机分为假手术组、高血压组、培哚普利组,术后4周末开始灌胃培哚普利片2mg/(kg.d),共8周。测量大鼠尾动脉收缩压、心脏重量/体重、心肌胶原容积分数(CVF)、血管周围胶原容积分数(PVCA)及转化生长因子-β1(TGF-β1)的表达。结果和假手术组相比,高血压组的收缩压、心脏重量/体重、CVF及PVCA显著增加(P<0.01),TGF-β1表达上调(P<0.01)。和高血压组相比,培哚普利组心脏重量/体重、CVF、PVCA及TGF-β1的表达降低(P<0.05)。结论培哚普利可以减轻肾性高血压大鼠心肌纤维化,其机制可能与下调TGF-β1有关。     

依普利酮对鸟苷酸环化酶偶联受体A基因敲除小鼠心肌纤维化的作用

背景 鸟苷酸环化酶偶联受体A(GC-A)为心钠素(ANP)和脑钠素(BNP)的共有受体,ANP和BNP通过与GC-A结合引起利尿、利钠及扩血管作用,并可抑制肾素和醛固酮分泌,GC-A基因敲除小鼠表现为高血压、心室肥厚和心肌纤维化.目的 探讨高选择性醛固酮受体拮抗剂依普利酮对鸟苷酸环化酶偶联受体A基因敲除(GC-A-KO)小鼠心肌纤维化的作用.方法 12周龄GC-A-KO雄性小鼠21只分成对照组(n=7)、依普利酮组[e-KO组,n=7,100 mg/(kg·d)×4周]和肼苯哒嗪组[h-KO组,n=7,10 mg/(kg·d)×4周],另有野生型(WT)小鼠7只用于测定血压、心率及组织学分析.小鼠于16周龄时处死,计算心脏与体质量比值(HW/BW);利用图像分析系统测量心肌胶原容积分数(CVF)和心肌血管周围胶原面积和管腔面积之比(PVCA);半定量RT-PCR法检测心室胶原纤维Ⅰ和胶原纤维Ⅲ mRNA在心肌组织表达.结果 依普利酮组和肼苯哒嗪组收缩压较对照组明显降低[分别为(103.2±4.2)和(99.6±6.2)vs(130.6±9.2)mm Hg,P均＜0.01];依普利酮组的HW/BW为(4.7±0.3)mg/g低于对照组(5.9±0.5)mg/g(P＜0.05),而肼苯哒嗪组HW/BW为(6.8±0.3)mg/g高于对照组(P＜0.05);与对照组比较,依普利酮组的CVF、PVCA及胶原纤维Ⅰ和胶原纤维Ⅲ mRNA的表达下降(P＜0.01、0.05和0.05),纤维化程度减轻;肼苯哒嗪组尽管血压下降程度与依普利酮组相似,但CVF、PVCA及胶原纤维Ⅰ和胶原纤维Ⅲ mRNA的表达均增加(P均＜0.05),纤维化程度加重.结论 依普利酮可独立于血压改善心肌纤维化和心室重构.     

依普利酮对鸟苷酸环化酶偶联受体A基因敲除小鼠心肌纤维化的作用

背景鸟苷酸环化酶偶联受体A(GC-A)为心钠素(ANP)和脑钠素(BNP)的共有受体,ANP和BNP通过与GC-A结合引起利尿、利钠及扩血管作用,并可抑制肾素和醛固酮分泌,GC-A基因敲除小鼠表现为高血压、心室肥厚和心肌纤维化。目的探讨高选择性醛固酮受体拮抗剂依普利酮对鸟苷酸环化酶偶联受体A基因敲除(GC-A-KO)小鼠心肌纤维化的作用。方法12周龄GC-A-KO雄性小鼠21只分成对照组(n=7)、依普利酮组[e-KO组,n=7,100mg/(kg.d)×4周]和肼苯哒嗪组[h-KO组,n=7,10mg/(kg·d)×4周],另有野生型(WT)小鼠7只用于测定血压、心率及组织学分析。小鼠于16周龄时处死,计算心脏与体质量比值(HW/BW);利用图像分析系统测量心肌胶原容积分数(CVF)和心肌血管周围胶原面积和管腔面积之比(PVCA);半定量RT-PCR法检测心室胶原纤维Ⅰ和胶原纤维ⅢmRNA在心肌组织表达。结果依普利酮组和肼苯哒嗪组收缩压较对照组明显降低[分别为(103.2±4.2)和(99.6±6.2)vs(130.6±9.2)mm Hg,P均<0.01];依普利酮组的HW/BW为(4.7±0.3)mg/g低于对照组(5.9±0.5)mg/g(P<0.05),而肼苯哒嗪组HW/BW为(6.8±0.3)mg/g高于对照组(P<0.05);与对照组比较,依普利酮组的CVF、PVCA及胶原纤维Ⅰ和胶原纤维ⅢmRNA的表达下降(P<0.01、0.05和0.05),纤维化程度减轻;肼苯哒嗪组尽管血压下降程度与依普利酮组相似,但CVF、PVCA及胶原纤维Ⅰ和胶原纤维Ⅲ mRNA的表达均增加(P均<0.05),纤维化程度加重。结论依普利酮可独立于血压改善心肌纤维化和心室重构。     

洛沙坦对老龄大鼠心肌纤维化的影响

目的探讨洛沙坦对老龄大鼠心肌纤维化的影响及其发生机制。方法W istar大鼠30只:青年组10只(3月龄);老年组20只(18月龄),其中非用药组10只,用药组10只(洛沙坦,20 mg.kg-1.d-1,用药8 w)。生化方法测定心肌羟脯氨酸浓度(HC),胶原VG染色法检测心肌胶原容积分数(CVF)、心肌血管周围胶原面积和管腔面积比例(PVCA);免疫组化法检测转化生长因子-β1(TGF-β1)在大鼠心肌组织的表达。结果与青年组相比,老年非用药组HC、CVF和PVCA明显增高(P<0.01,P<0.001,P<0.01);与老年非用药组相比,老年用药组上述指标明显降低(P<0.05,P<0.01,P<0.05),TGF-β1表达在老年非用药组较青年组明显增强(P<0.05)。TGF-β1表达与HC、CVF和PVCA呈正相关(rs分别为0.462、0.391、0.416;P<0.01,P<0.05,P<0.05)。结论TGF-β1随增龄表达逐渐增加,可能参与了增龄过程中老龄大鼠心肌纤维化的形成。洛沙坦在一定程度上抑制了老龄大鼠心肌纤维化的形成。     

中药降压脉净对心肌组织转化生长因子-β1的影响及干预心肌纤维化的作用

目的 探讨中西医结合方法预防和干预自发性高血压大鼠心室重构心肌纤维化的病理改变及其作用机制.方法 自发高血压大鼠(SHR)8周龄40只,随机分为4组,每组10只,并以SD大鼠8周龄10只作为对照组,分别进行药物观察,疗程20周.观察心脏重量指数,心肌胶原容积分数(CVF),血管周围胶原面积(PVCA),Ⅰ、Ⅲ型胶原的表达.免疫组织化学法检测心肌组织转化生长因子-β1(TGF-β1)蛋白水平和RT-PCR检测心肌组织内TGF-β1mRNA的表达.结果 ①心脏重量指数、CVF、PVCA治疗组与模型组比较有显著性减少,与西药对照组和中药对照组比较亦有减少.②病理学改变偏光镜下观察Ⅰ、Ⅲ型胶原的表达中治疗组的表达明显比模型组减少,与西药对照组和中药对照组比较也有减少趋势.③TGF-β1治疗组的药后值显著地低于模型组(P＜0.01),同时也显著低于西药组(P＜0.05).结论 ①心肌中胶原蛋白含量明显增加的机制可能与转化生长因子-β1的高表达有关.②中药降压脉净剂具有抑制自发性高血压大鼠心肌纤维化的作用.其作用机制可能与抑制TGF-β1的高表达有关,在干预和逆转心肌纤维化方面优于单纯西药络活喜对照组,也有优于中药对照组的趋势.     

辛伐他汀对自发性高血压大鼠左心室肥厚作用及心肌转化生长因子-β1表达影响

目的观察辛伐他汀对自发性高血压大鼠左心室肥厚作用及心肌转化生长因子-β1(TGF-β1)表达的的影响。方法实验用WKY大鼠做阴性对照组,SHR大鼠分为对照组和辛伐他汀治疗组。测量大鼠尾动脉收缩压(SBP)及左心室重量指数(LVMI)。应用HE、VG染色、免疫组织化学的方法,结合计算机图像分析技术,检测心肌细胞的直径(TDM)和面积(CA)、心肌组织胶原体积比例(CVF)、血管周围胶原面积和管腔面积比例(PVCA)以及左心室心肌TGF-β1表达。结果辛伐他汀组未能有效降低血压,但可以降低左心室肥厚;SHR辛伐他汀组与SHR对照组相比TDM、CA、CVF、PVCA明显降低,TGF-β1表达下调明显(均P<0.05)。结论应用辛伐他汀治疗可逆转高血压大鼠左心室肥厚形成,TGF-β1可能与辛伐他汀逆转左心室肥厚的机制有关。     

结缔组织生长因子与高血压大鼠心肌纤维化相关性及伊贝沙坦的干预研究

目的探讨结缔组织生长因子(CTGF)在高血压大鼠心肌纤维化发生发展中的作用,以及伊贝沙坦改善高血压所致心室重构和心肌纤维化可能的作用机制。方法20只12周龄雄性自发性高血压大鼠(SHR)随机分为SHR组和伊贝沙坦(IRB)组各10只,IRB组每只大鼠予以伊贝沙坦50 mg.kg-1.d-1灌胃,给药时间12周,同时取10只12周龄雄性Wistar大鼠作为对照组(WKY组),用免疫组织化学的方法对转化生长因子β1(TGF-β1)、CTGF在3组大鼠的左室心肌的分布及表达进行半定量分析;用逆转录-聚合酶链反应检测TGF-β1、CTGF mRNA在心肌表达水平;用MOSSON染色法观察左室心肌胶原形态,图像分析测量胶原容积分数(CVF)和血管周围胶原面积(PVCA)。结果(1)左室重量指数(LVI)、CVF、PVCA在SHR大鼠组明显高于WKY大鼠组(P<0.01);与SHR组比较,伊贝沙坦组则显著降低(P<0.05)。(2)CTGF主要在血管平滑肌和心肌间质中表达,相关分析表明:CTGF与TGF-β1(r=0.562,P<0.05)、CVF(r=0.715,P<0.01)、PVCA(r=0.786,P<0.01)呈正相关;(3)CTGF及其mRNA在SHR组左室心肌中的表达较WKY组明显增强(P<0.05),与SHR组比较,IRB组则明显减少。结论高血压大鼠心室肌CTGF表达增加,伊贝沙坦能抑制高血压大鼠心室肌CGTF表达,且明显改善了高血压心室重构和心肌纤维化。     

阿托伐他汀对大鼠心肌梗死后心肌纤维化的干预作用

目的通过研究阿托伐他汀对大鼠急性心肌梗死(AMI)后periostin蛋白及转化生长因子β1(TGF-β1)mRNA的表达水平的影响,探讨阿托伐他汀对于AMI后心肌纤维化的干预作用机制。方法将60只SD雄性大鼠随机分为正常组(Sham)、单纯心肌梗死组(MI)和心肌梗死联合阿托伐他汀组(Ato);注射异丙肾上腺素造心肌梗死模型,Ato组于心肌梗死造模成功后给予阿托伐他汀5 mg/(kg·d)灌胃,MI组及Sham组以同等剂量生理盐水灌胃;各组分别于术后8周取材,病理技术:Masson染色观察并计算心肌纤维化中胶原纤维的容积分数(CVF);利用RT-PCR技术检测心肌periostin蛋白及TGF-β1 mRNA的表达水平。结果 Masson染色提示MI组及Ato组CVF均显著高于Sham组(P0.01);而Ato组CVF明显低于MI组(P0.05);RT-PCR结果MI组和Ato组较Sham组的TGF-β1 mRNA及periostin蛋白表达量均显著增加(P0.01);Ato组比MI组TGF-β1 mRNA及periostin蛋白的表达量显著下降(P0.05)。结论阿托伐他汀能够抑制periostin蛋白和TGF-β1 mRNA的表达,其机制可能为抑制TGF-β1/periostin信号传导通路,进而抑制心肌纤维化,并保护心脏功能。     

下丘脑室旁核炎性细胞因子在依普利酮改善心力衰竭中的作用

目的探讨下丘脑室旁核(PVN)炎性细胞因子在依普利酮(EPL)改善心力衰竭中的作用。方法Wistar大鼠分为假手术组(n=6)、模型组(n=10)、吡咯烷二硫基甲酸盐(PDTC)组(n=10)、依普利酮组(n=10)。结扎左冠状动脉前降支诱导急性心肌梗死后心力衰竭,根据分组情况分别给予PDTC[(150 mg/(kg·d)]、依普利酮[30 mg/(kg·d)]和清洁蒸馏水灌胃,假手术组只在相同位置穿线而不结扎。6周后进行血流动力学测定,留取下丘脑、血浆标本,检测PVN内肿瘤坏死因子α(TNF-α)、核因子κB/p65(NF-κB/p65)、促肾上腺皮质激素释放激素(CRH)及血管紧张素Ⅱ(AngⅡ)的表达,并检测血浆TNF-α、去甲肾上腺素(NE)、醛固酮(ALD)水平。结果依普利酮和PDTC干预后大鼠心功能较模型组明显改善。模型组血浆ALD、NE、TNF-α水平显著升高,而依普利酮和PDTC干预后ALD、NE、TNF-α水平降低(P0.05)。模型组PVN内CRH、AngⅡ表达显著增多,依普利酮和PDTC干预后PVN内CRH、AngⅡ表达显著减少(P0.05),NF-κB/p65在依普利酮组和PDTC组的表达较模型组显著降低(P0.05)。依普利酮、PDTC可降低PVN内CRH阳性神经元表达。结论心力衰竭时大鼠PVN内炎性细胞因子表达增多,依普利酮可以改善心力衰竭大鼠心功能,与抑制PVN内炎性细胞因子过表达有关。     

Anaerobic myocardial abscess following myocardial infarction

An anaerobic myocardial abscess due to Bacteroides fragilis developed in a 60-year-old man when he had an acute myocardial infarction while recuperating from surgery for a paracolonic abscess. Anaerobic bacteremia is a common event and may lead to infection in areas of low oxygen tension far removed from the original portal of entry.     

曲尼司特对心肌梗死后心肌间质纤维化的影响

目的探讨曲尼司特对兔心肌梗死后心肌间质纤维化干预作用。方法结扎左前降支制作兔心肌梗死模型,分实验组和对照组。3周后经胃管分别给予曲尼司特及安慰剂1月,心脏彩超评价心功能并检测血清转化生长因子（transform ing growth factor,TGF-β1）,I、III型胶原浓度及组织羟脯胺酸含量。结果实验组治疗前后心功能、心腔内径、室壁厚度明显改善,血清TGF-β1,I、III型胶原浓度及羟脯胺酸含量较对照组明显下降。结论曲尼司特可有效拮抗心肌梗死后心肌间质纤维化,预防心室重构。     

Transient myocardial ischaemia after acute myocardial infarction

The prevalence and characteristics of transient myocardial ischaemia were studied in 203 patients with recent acute myocardial infarction by both early (6.4 days) and late (38 days) ambulatory monitoring of the ST segment. Transient ST segment depression was much commoner during late (32% patients) than early (14%) monitoring. Most transient ischaemia (greater than 85% episodes) was silent and 80% of patients had only silent episodes. During late monitoring painful ST depression was accompanied by greater ST depression and tended to occur at a higher heart rate. Late transient ischaemia showed a diurnal distribution, occurred at a higher initial heart rate, and was more often accompanied by a further increase in heart rate than early ischaemia. Thus in the first 2 months after myocardial infarction transient ischaemia became increasingly common and more closely associated with increased myocardial oxygen demand. Because transient ischaemic episodes during early and late ambulatory monitoring have dissimilar characteristics they may also have different pathophysiologies and prognostic implications.     

Assessment of myocardial viability using myocardial contrast echocardiography

Myocardial contrast echocardiography (MCE) is a technique that uses microbubbles as a tracer during simultaneous ultrasound of the heart. The microbubbles can be used to provide quantitative information regarding the adequacy of myocardial blood flow (MBF), as well as the spatial extent of microvascular integrity. In acute myocardial infarction, MCE can identify the presence of collateral flow within the risk area, and can therefore predict preservation of myocardial viability and ultimate infarct size even prior to reperfusion. After reperfusion, the extent of microvascular no-reflow can be determined, and has significant implications for recovery of left ventricular function. In chronic ischemic heart disease, MCE has also been shown to successfully differentiate viable from necrotic myocardium. This technique can accurately predict recovery of function after revascularization. More importantly, MCE can be used to identify viable segments that may help to prevent infarct expansion and remodeling, and thus improve patient outcomes.     

Assessment of myocardial viability with myocardial contrast echocardiography

The application of noninvasive imaging techniques to assess myocardial viability has become an important part of routine management of patients with acute myocardial infarction and chronic coronary artery disease. Information regarding the presence and extent of viability may help identify patients likely to benefit from revascularization or therapy directed at attenuating left ventricular remodeling. Myocardial contrast echocardiography (MCE) is capable of defining the presence and extent of viability by providing an accurate assessment of microvascular integrity needed to maintain myocellular viability. It is especially suited for the spatial assessment of perfusion, even when myocardial blood flow is reduced substantially in the presence of severe epicardial stenoses or in a bed dependent on collateral perfusion. The routine use of MCE to evaluate viability in patients with acute and chronic coronary artery disease is now feasible with the advent of new imaging technologies and microbubble agents capable of myocardial opacification from venous injections. The utility of this technique for determining treatment strategies has not been established but is forthcoming.     

经静脉心肌声学造影评价心肌梗死后存活心肌的价值

目的　探讨经静脉心肌声学造影 (MCE)对心肌梗死后存活心肌的诊断价值。方法　 2 4例心肌梗死患者用二维超声评价室壁运动情况 ,同时经静脉进行MCE ,以 3个月后静态超声心动图左室心肌节段性运动改善为依据评价MCE对心肌梗死后存活心肌的诊断价值。结果　在 2 4例病人的 384个心肌节段中 ,运动异常节段 184个。在运动异常的 184个节段中 ,MCE1分 39段 ,0 5分 5 0段 ,0分 95段。 3个月复查 79个节段有运动改善 ,其中 39段来自MCE1分的心肌 ,4 0段来自MCE0 5分的心肌。MCE对预测心肌梗死后室壁运动改善的敏感性、特异性、阳性预测值、阴性预测值及准确率分别为 :10 0 %、89 7%、84 8%、10 0 %和 94 6 %。结论　MCE能比较准确地预测心肌梗死后心肌的存活性     

Transient myocardial ischaemia after acute myocardial infarction.

The prevalence and characteristics of transient myocardial ischaemia were studied in 203 patients with recent acute myocardial infarction by both early (6.4 days) and late (38 days) ambulatory monitoring of the ST segment. Transient ST segment depression was much commoner during late (32% patients) than early (14%) monitoring. Most transient ischaemia (greater than 85% episodes) was silent and 80% of patients had only silent episodes. During late monitoring painful ST depression was accompanied by greater ST depression and tended to occur at a higher heart rate. Late transient ischaemia showed a diurnal distribution, occurred at a higher initial heart rate, and was more often accompanied by a further increase in heart rate than early ischaemia. Thus in the first 2 months after myocardial infarction transient ischaemia became increasingly common and more closely associated with increased myocardial oxygen demand. Because transient ischaemic episodes during early and late ambulatory monitoring have dissimilar characteristics they may also have different pathophysiologies and prognostic implications.