氯化血红素诱导大鼠肝脏血红素加氧酶1表达对急性乙醇性肝损害的保护作用

目的观察氯化血红素（heroin）对大鼠肝脏血红素加氧酶-1（HO-1）的诱导表达作用，并探讨HO-1对大鼠急性乙醇性肝损害的防治作用。方法SD大鼠28只随机分为三组：模型组（10只），予白酒连续灌胃10d制造急性乙醇性肝损害模型；hemin处理组（10只），在hemin腹腔注射基础上予白酒灌胃；正常对照组（8只），生理盐水灌胃。第10d处死大鼠后检测血清ALT、AST、SOD、MDA水平，光镜观察肝组织细胞形态学改变，采用逆转录聚合酶链反应（RT—PCR）检测肝组织HO-1mRNA表达以及免疫组织化学方法观察HO-1的表达。结果hemin处理组与正常对照组大鼠血清ALT、AST、MDA水平明显低于模型组，SOD水平明显高于模型组。模型组肝细胞肿胀、炎症细胞浸润等形态学改变比hemin处理组与正常对照组明显。hemin处理组HO-1表达明显高于模型组与正常对照组。结论hemin能诱导大鼠肝组织HO-1表达增加，提高HO-1表达对大鼠急性乙醇性肝损伤有保护作用。     

改变血红素加氧酶-1水平对糖尿病大鼠氧化应激状态及肾功能的影响

目的 探讨血红素加氧酶-1(HO-1)对糖尿病(DM)大鼠氧化应激状态及肾功能的影响.方法 以链脲佐菌素诱导DM大鼠模型.SD大鼠分成4组:对照组、DM组、正铁血红素Hemin(HO-1)诱导剂组、ZnPP(HO-1抑制剂)组.检测血清总抗氧化能力(TAOC)、丙二醛(MDA)含量和尿白蛋白排泄率(UEA);RT-PCR法检测肾脏组织TNF-α和HO-1mRNA表达水平.结果 Hemin组血清总抗氧化能力与DM组相比明显增高;而给予ZnPP后DM大鼠MDA含量增加,总抗氧化能力降低;DM大鼠UEA上升(P均<0.01),并随病程延长而加重.Hemin组UEA与DM 5 w组相比已有下降趋势,但尚无统计学差异(P>0.05);ZnPP组大鼠UEA明显增高(P<0.01);与对照组相比,DM大鼠肾组织TNF-α及HO-1 mRNA表达增加;应用Hemin后DM大鼠肾脏组织TNF-α表达减少(P<0.01).结论提高DM大鼠肾脏HO-1表达水平可以改善肾组织氧化应激状态、延缓肾功能障碍.     

血红素氧合酶-1及一氧化碳-胆红素系统对心力衰竭大鼠心功能的保护作用

目的探讨经胃肠道给予氯化高铁血红素后.体内血红素氧合酶-1(HO-1)及一氧化碳-胆红素(CO-胆红素)的反应和对大鼠慢性压力负荷性心力衰竭(心衰)进程的影响。方法将成年雄性SD大鼠63只,随机分为血红素组、心衰组和对照组,每组21只。术后3周血红素组以60 mg·kg~(-1)·d~(-1)氯化高铁血红素灌胃,另外2组同时间灌以同体积生理盐水。并分别在4、8、12周检测血清HO-1、碳氧血红蛋白(COHb);测定尾动脉压;经颈动脉插管检测平均动脉压、左心室收缩压(LVSP)、左心室舒张末压(LVEDP)以及左心室压力最大上升速率(+dp/dt_(max))和左心室压力最大下降速率(—dp/dt_(max))。结果与对照组比较,心衰组8、12周时HO-1和COHb含量明显升高(P<0.01);与心衰组比较,血红素组在4、8、12周时HO 1和COHb含量明显升高(P<0.01),8周时尾动脉压、平均动脉压和LVSP明显降低(P<0.01),8、1 2周时LVEDP明显降低(P<0.05,P<0.01),12周时±dp/dt_(max)明显升高(P<0.01)。结论经胃肠道给予氯化高铁血红素可对体内HO-1产生诱导作用;HO-1及CO-胆红素系统的诱导能减缓压力负荷性心衰大鼠心衰的进展,对心脏的收缩和舒张功能有保护作用。     

硫化氢对大鼠压力负荷性心力衰竭发展过程中氧化应激的影响

目的腹主动脉缩窄大鼠心力衰竭(心衰)模型通过腹腔给予硫化氢(H_2S)供体硫氢化钠(NaHS),观察压力负荷性心衰形成过程中H_2S对氧化应激状态的影响。方法 SD大鼠63只,随机分为对照组、心衰组、NaHS组,每组21只。各组均在第4、8、12周时,各取7只大鼠取血及心脏进行检测。结果心衰组4、8、12周血清H_2S含量、心肌H_2S合酶活性均较对照组明显降低,NaHS组4、8、12周血清H_2S含量较心衰组明显升高,心肌H_2S合酶活性较心衰组略有增高,但仍低于对照组。与对照组比较,心衰组4、8、12周血清MDA含量明显升高,超氧化物歧化酶(SOD)活性明显降低;与心衰组比较,NaHS组SOD活性上升,MDA含量下降,其中MDA含量在8、12周时下降明显,但仍明显高于对照组;SOD在12周时明显增高,但仍明显低于对照组。与心衰组比较,NaHS组4、8、12周血清氧化型低密度脂蛋白含量明显降低,但8、12周时仍明显高于对照组。结论外源性给予H_2S供体NaHS能改善压力负荷引起的心衰大鼠体内和心肌内的氧化应激状态,可能是H_2S心脏保护作用机制之一。     

血红素加氧酶-1对慢性肾功能衰竭大鼠高血压的影响

目的建立大鼠慢性肾功能衰竭高血压模型,研究血红素加氧酶-1(HO-1)对慢性肾功能衰竭大鼠血压的影响,并探讨血红素加氧酶-1在慢性肾衰血压调节中的作用和机制.方法5/6肾切除法建立慢性肾功能衰竭,大鼠随机分成3组①正常组,②肾衰组,③Hemin组(肾衰+HO-1诱导剂组).检测术后第6、8、10周的血压,第10周血清尿素氮、肌酐、血浆和肾组织丙二醛(MDA),双波长分光光度法测量血浆内源性CO的水平,观察第10周肾脏病理改变,免疫组织化学方法检测肾组织HO-1的表达,应用RT-PCR和Western Blot检测肾组织HO-1 mRNA和蛋白质的表达.结果诱导慢性肾功能衰竭大鼠体内HO-1表达可以①明显升高血浆内源性CO水平(P＜0.05);②减少血浆和肾组织MDA;③明显降低慢性肾功能衰竭大鼠血压(P＜0.01);④降低血清尿素氮、肌酐(P＜0.01);⑤减轻肾小球系膜增生、间质损害.结论HO-1可以通过释放内源性CO和减少血浆氧化应激水平而降低慢性肾衰大鼠血压,此外它还可能具有降压效应以外的肾脏保护作用.     

氯高铁血红素对肾性高血压大鼠离体血管反应性的影响

目的:利用两肾一夹(2 K1C)肾性高血压大鼠模型,观察了氯高铁血红素(HL L )对高血压大鼠血压的影响及离体主动脉环反应性的改变,探讨HL L对肾性高血压发生发展的影响及机制。方法:1制作肾性高血压大鼠模型,分别于2、4、6、8周记录大鼠的血压改变。2腹腔注射HL L ,观察血压的改变     

抑制血红素氧合酶-1对大鼠免疫性肝纤维化的影响

目的:逆向观察肝纤维化大鼠血红素氧合酶-1(heme oxygenase 1, HO-1)的表达与肝纤维化形成的关系, 探讨HO-1对免疫性肝纤维化大鼠肝脏的保护作用.方法:应用人体血清白蛋白建立免疫性肝纤维化模型, Zn组在攻击阶段同时腹腔注射Znpp, HE染色、VG染色、Foot氏网状纤维染色等三种染色方法观察肝纤维组织增生程度,Western blot和免疫组化法观察肝组织中HO-1的表达.结果:F组和Zn组免疫组化阳性计分较N组明显升高(4.00±1.31, 2.33±0.78 vs 0.80±0.79,P<0.01);且F组免疫组化阳性计分比Zn组高(4.00±1.31 vs 2.33±0.78, P<0.05). F组成纤维细胞、Ⅰ型胶原及Ⅲ型胶原增生较N组明显( P<0.01);Zn组成纤维细胞、Ⅰ型胶原及Ⅲ型胶原增生较F组更明显( P<0.01).结论:免疫性肝纤维化模型中, 肝脏能够高水平表达HO-1, 对肝脏起保护作用.     

血红素加氧酶-1对慢性肾功能衰竭大鼠高血压的影响

目的 建立大鼠慢性肾功能衰竭高血压模型，研究血红素加氧酶-1(HO-1)对慢性肾功能衰竭大鼠血压的影响，并探讨血红素加氧酶-1在慢性肾衰血压调节中的作用和机制。方法 5／6肾切除法建立慢性肾功能衰竭，大鼠随机分成3组：①正常组，②肾衰组，③Hemin组(肾衰 HO-1诱导剂组)。检测术后第6、8、10周的血压，第10周血清尿素氮、肌酐、血浆和肾组织丙二醛(MDA)，双波长分光光度法测量血浆内源性CO的水平，观察第10周肾脏病理改变，免疫组织化学方法检测肾组织HO-1的表达，应用RT-PCR和Western Blot检测肾组织HO-1 mRNA和蛋白质的表达。结果 诱导慢性肾功能衰竭大鼠体内HO-1表达可以：①明显升高血浆内源性CO水平(P＜0．05)；②减少血浆和肾组织MDA；③明显降低慢性肾功能衰竭大鼠血压(P＜0．01)；④降低血清尿素氮、肌酐(P＜0．01)；⑤减轻肾小球系膜增生、间质损害。结论 HO-1可以通过释放内源性CO和减少血浆氧化应激水平而降低慢性肾衰大鼠血压，此外它还可能具有降压效应以外的肾脏保护作用。     

血红素氧合酶-1对心力衰竭大鼠肠道炎症的保护机制

目的：研究血红素氧合酶-1（HO-1）对心力衰竭（心衰）大鼠肠道炎症的保护机制。方法通过冠状动脉结扎术造成心肌梗死建立心衰大鼠模型（雄性,Wistar大鼠）,每组10只,分为心肌梗死（MI）模型组、MI＋钴-原卟啉（MI＋Copp）组、MI＋锡中卟啉（MI＋SnMP）组,以正常大鼠作为对照组,分别腹腔注射生理盐水、Copp溶液、SnMP溶液。8周后取门静脉及下腔静脉血检测血浆内毒素含量,通过Western印迹测定小肠HO-1的表达,比色法测定小肠一氧化碳（CO）浓度,酶联免疫吸附法测定小肠肿瘤坏死因子-α和白细胞介素-10水平。结果与MI组比较,MI＋Copp组HO-1和CO水平明显升高,血浆内毒素含量减少,肠道炎症减轻,而MI＋SnMP组HO-1无明显变化,CO明显降低,血浆内毒素浓度升高,小肠炎症加重。结论 HO-1可抑制心衰大鼠肠道炎症,该作用可能与CO有关。     

氯化血红素对全脑缺血/再灌注大鼠海马CA1区神经元凋亡和caspase-3表达的影响

目的探讨氯化血红素(Hemin)对全脑缺血/再灌注(I/R)海马CA1区神经元的保护作用及机制。方法将138只Wistar雄性大鼠随机分为四组,对照组只凝闭双侧椎动脉,暴露但不夹闭双侧颈总动脉;I/R组凝闭双侧椎动脉,夹闭双侧颈总动脉8 min后恢复血液再灌流;预防组在全脑缺血前按药物不同剂量、时间、途径、次数给药,手术操作同I/R组;治疗组手术操作同I/R组,按全脑缺血8 min恢复血液再灌流后按药物不同剂量、时间、途径、次数给药。采用凋亡细胞原位标记法检测各组大鼠海马CA1区神经细胞凋亡阳性个数,采用免疫组化法检测半胱氨酸天冬氨酸蛋白酶(caspase)-3表达变化。结果 I/R组、预防组、治疗组凋亡细胞及caspase-3阳性细胞数明显高于对照组,预防组、治疗组凋亡细胞及caspase-3阳性细胞数明显低于I/R组,P均<0.05。结论 Hemin在脑缺血前后的有效时间内对I/R大鼠海马CA1区神经有保护作用,其机制可能为抑制caspase-3表达,减少细胞凋亡。     

Remodeling of outward K+ currents in pressure-overload heart failure

Objectives: Outward K⁺ currents are critical determinants of action potential repolarization and the site of action of a number of electrophysiologically active drugs. Further, expression and processing of the channels underlying these currents is altered in heart disease. Here, we investigated the native transmural gradient of outward K⁺ currents in murine left ventricle (LV) and delineated disease‐related remodeling of these currents in heart failure (HF). Methods: Pressure‐overload heart failure was induced in mice by thoracic aortic constriction. Outward K⁺ currents were recorded using the whole‐cell patch clamp technique in acutely dissociated ventricular myocytes. Results: Unambiguous gradients of outward K⁺ current density and Kv4.2 protein abundance were observed across the wall of the LV, with significantly larger current density and protein levels in subepicardial (SEP) myocytes, compared with subendocardial (SEN) myocytes. Voltage dependences of current activation and inactivation were similar in SEP and SEN myocytes. In failing LV, however, outward K⁺ current density was significantly decreased in SEP but not in SEN cells leading to elimination of the native transmural gradient. In failing LV, the voltage dependences of K⁺ current activation and inactivation were not altered. However, current inactivation (decay) was significantly accelerated and recovery from inactivation was significantly slowed. Consistent with this, Western blot analysis revealed a decrease in KChIP2 protein abundance in failing LV. Conclusions: This is the first report of HF‐related remodeling of outward K⁺ currents in murine LV. Similar to humans, disease‐related remodeling occurs differentially across the murine ventricular wall, leading to loss of the native gradient of repolarization. Together with slowed recovery from inactivation, these alterations likely promote abnormal impulse conduction, a major proarrhythmic mechanism.     

氟伐他汀防治缺血性心脏病心衰及其抗氧化应激作用的实验研究

目的:探讨羟甲基戊二酰辅酶A（HMG CoA）还原酶抑制剂氟伐他汀防治缺血性心脏病心衰疗效及其抗氧化应激作用。方法:雌性SD大鼠42只,急性心肌梗死（AMI）术后6h随机分为:①AMI对照组（n=24）;②氟伐他汀组（n=18）;③另设假手术组（n=10）。直接灌胃给药8周后行高频多普勒超声、血流动力学、心脏重塑指标、左心室α、βMHC的mRNA表达、心肌总抗氧化能力（TAOC）和丙二醛（MDA）测定。结果:与假手术组相比,AMI组左室舒张末期内径（LVEDd）、左室舒张末期容积（LVEDV）、E峰、E峰减速度、E/A、左室舒张末压（LVEDP）、左、右心室心肌肥厚指数、βMHCmRNA和MDA均显著增加,左室短轴缩短率（FS）、射血分数（EF）、αMHCmRNA和TAOC均显著降低。与AMI组相比,氟伐他汀组的LVEDd、LVEDV、E峰、E峰减速度、E/A、LVEDP和左、右心室心肌肥厚指数、βMHCmRNA及MDA均显著降低,FS、EF、αMHCmRNA和TAOC显著升高。结论:氟伐他汀能抑制心室重塑,预防缺血性心脏病心衰发生;抗氧化应激作用可能是其机制之一。     

络风宁2号对心力衰竭大鼠心功能的影响

目的：观察络风宁2号对心力衰竭大鼠的心功能的影响。方法60只雄性Wistar大鼠,随机分为正常对照组（n=12）,模型组（n=12）,络风宁2号组（n=12）,风药组（n=12）和芪苈组（n=12）。除正常对照组外,其他各组均按以下方法制备心衰模型,腹腔注射异丙肾上腺素、盐水喂饲,按照所属组别分别进行药物干预。观察大鼠心功能、心脏组织病理学改变。结果与正常对照组比较,其他各实验组心脏质量/体重比均增高（P＜0.01）,但实验组间无统计学差异（P＞0.05）。模型组心脏左室舒张末期内径（LVIDd）较正常对照组增大,LVIDd较模型组有所恢复,以络风宁2号组和芪苈组恢复更为明显,但组间比较未见明显差异（P＞0.05）,实验组心率、左室收缩末期内径（LVIDs）、左室短轴缩短率（LVFS）、左室射血分数（LVEF）及心肌病理学等变化一致。结论络风宁2号对大鼠心衰有确切治疗作用,疗效与芪苈强心胶囊相当。     

超声心动图在评估犬慢性心力衰竭模型中的作用

目的探讨超声心动图在评估犬慢性心力衰竭模型中的作用。方法对10只比格犬进行快速右心室起搏,起搏前及起搏4周停止起搏后进行多普勒超声心动图和血流动力学检查。结果快速右心室起搏4周后,所有犬都出现气促、四肢浮肿等情况,并有不同程度的胸、腹腔积液。超声心动图示左室EF、FS较起搏前显著降低（P<0.01）,分别为（0.63±0.05）vs（0.42±0.10）和（0.33±4.50）vs（0.19±6.19）;血流动力学检测示犬左室±dp/dtm ax较起搏前均显著降低（P<0.01）,分别为[（9846±415）vs（3330±307）mmHg/s]和[（-7925±3558）vs（-2260±113）mmHg/s]。起搏前后犬左室EF和FS值与+dp/dtm ax值呈良好的正相关（P<0.01）。结论通过超声心动图和血流动力学指标的相关性分析,表明超声心动图在评价心力衰竭动物模型上是无创、便捷、重复性好的方法。     

Evidence of oxidative stress in chronic heart failure in humans

Chronic heart failure (CHF) due to coronary artery disease (CAD)has been shown to be associated with increased plasma thiobarbituricreactive substances (TBARS) and reduced plasma thiol (PSH) concentrations,suggesting oxidative stress (OS). The aims of the present studieswere (a) to determine whether OS is due to CAD or CHF per seand (b) to determine if a wider range of more specific markersof OS are abnormal in CHF. In the first study, two groups of patients (n = 15 each) werecompared. Group 1 (11 male, mean age 56 years) had CHF due toCAD and group 2 (12 male, mean age 53 years) had non-CAD CHF.Median plasma TBARS in controls was 7.6 nmol . ml^–1 ,10.0 nmol . m^–1 in group 1 and 9.3 nmol. ml^–1 ingroup 2 (P < 0.01 both groups vs control). Median PSH was505 384 and 364 nmol. ml^–1 (P < 0.05 and P < 0.01vs control) respectively. Fifty-three patients with CHF were recruited in the second study.Malondialdehyde and PSH were 10.3 and 409 nmol. ml^–1 respectively,compared to control values of 7.9 and 560 nmol. ml^.1 (both P< 0.001). The median values for the following additionalmeasures of OS in controls and patients were: erythrocyte superoxidedismustase 131 vs 114 U . l^–1 (P = 0.005); caeruloplasminoxidase 97 vs 197 U. l^–1 (P < 0.01); erythrocyte glutathione1.56 nmol . ml^–1 vs 1.77 nmol . ml^–1 (P < 0.02);plasma conjugated dienes 0.28 vs 0.33 optical density units(P = ns). Chronic heart failure, regardless of aetiology, is associatedwith abnormalities of a range of markers of OS.     

阿霉素致大鼠心力衰竭干预起点探讨

目的探讨阿霉素导致大鼠心力衰竭心室结构演变和应用此模型进行心力衰竭治疗性试验时恰当的干预起点。方法以累积剂量达15mg/kg,3周内注射完毕的方法建立阿霉素致大鼠心力衰竭模型。分别于注射阿霉素前,注射后3、4、5、6周和7周在M型超声下观察左心室舒张末期内径(left ventricular end-diastolic dimension,LVEDd),左心室收缩末期内径(left ventricular end-systolic dimension,LVESd)和左心室射血分数(left ventricular ejection fraction,LVEF)变化;于注射阿霉素前,注射后6周,7周使用免疫酶联吸附法(ELISA)法检测血清脑利钠肽浓度。结果注射阿霉素7周后与注射阿霉素前比较,LVEF(69.6%±10.3%vs.78.7%±13.7%,P0.01),LVEDd[(0.67±0.03)cmvs.(0.52±0.02)cm,P0.01],LVESd[(0.41±0.17)cmvs.(0.30±0.02)cm,P0.01]和脑钠肽[(0.37±0.15)μg/Lvs.(0.18±0.06)μg/L,P0.01]差异有统计学意义。结论足量注射阿霉素7周后可作为阿霉素致大鼠心衰模型治疗性试验时干预的起点。     

Effects of deferoxamine on H2O2-induced oxidative stress in isolated rat heart

During myocardial reperfusion injury, iron has been implicated in the Fenton based generation of hydroxyl radical, ·OH, leading to further organ injury. Although previous studies have investigated the protective effect of iron chelators including deferoxamine (DFX) in myocardial reperfusion injury, there is little information regarding the role of iron chelation during oxidative stress produced by H₂O₂ on the heart. Isolated hearts from male Sprague-Dawley rats were retrograde-perfused with Krebs-Henseleit solution at 5 ml/min. After a 60-min equilibration, oxyradical challenge was instituted by the addition of H₂O₂ (200–600 M) to the perfusate for 60 min. A subgroup of animals received DFX (400 M) in the perfusate prior to challenge with 400 M H₂O₂. Contractility was continuously monitored; perfusate samples for glutathione (GSH) and lactate dehydrogenase (LDH) estimations were collected at 30-min intervals. Headspace ethane, an indicator of lipid peroxidation, was estimated at 30-min intervals by gas chromatography. Control hearts maintained contractility during the perfusion period. H₂O₂ perfusion caused a dose dependent decrease in myocardial contractility; DFX pretreatment was partialy protective. Headspace ethane slowly accumulated in control hearts; perfusion with H₂O₂ caused dose dependent increase in ethane accumulation indicative of enhanced lipid peroxidation. GSH and LDH in the perfusate remained low in control hearts. In contrast, H₂O₂ treated hearts had a dose dependent inclease in the efflux of GSH and LDH which was markedly increased by perfusion with 600 M H₂O₂. Pretreatment with DFX did not significantly reduce GSH or LDH efflux from hearts perfused with peroxide. While H₂O₂ perfused with peroxide. While H₂O₂ perfusion causes a dose dependent decrease in myocardial contractility with a corresponding increase in headspace ethane release with GSH & LDH efflux indicative of oxidative stress, concurrent treatment with DFX reduces myocardial dysfunction and ethane generation. However, sublethal damage of plasma membrane still continues as reflected by continuous enhancement of LDH efflux, possibly indicating involvement of other reactive species besides hydroxyl radical.     

压力-容积环评价压力负荷型慢性心力衰竭大鼠左心室功能的意义

目的采用压力-容积(P-V)环研究压力超负荷对大鼠左心室血流动力学的影响。方法 13只SD大鼠随机分为2组:假手术(Sham)组(n=7)和心力衰竭(HF)组(n=6)。HF组采用腹主动脉缩窄法制备模型,Sham组只穿线不缩窄。对两组大鼠进行血流动力学检测,大鼠麻醉后经右颈总动脉向左心室内插入Millar导管(SPR-838),记录两组大鼠的P-V变化。结果与Sham组相比,HF组大鼠的心脏(P0.01)和肺脏(P0.05)重量均显著增加。在稳定状态的P-V环中可以看到,和Sham组相比,在压力超负荷的影响下,HF组左心室P-V环明显增高、右移,P-V曲线斜率也明显高于Sham组,左心室收缩/舒张末期压力(P_(es)/P_(ed))、收缩/舒张末容积(V_(es)/V_(ed))、压力衰退的时间常数(Tau)均增高(P0.05),而室内压最大上升速率(dP/dt_(max))、左室压力最大下降速率(-dP/dt_(min))、射血分数(EF)和每搏输出量(SV)均出现降低(P0.05)。结论压力负荷型慢性HF大鼠左心室发生了舒张和收缩功能障碍,并且伴有一定程度的左心室肥大。P-V环能够准确地定性、定量评价大鼠的心功能。