短时间缺血诱导亚铁血红素氧化酶-1对大鼠80%肝切除的影响

目的：观察短时间缺血对大鼠80％肝切除术后肝功能的影响，并对其作用机制进行探讨。方法：12只大鼠分成两组，缺血组肝右叶缺血15min,24h后行缺血肝叶亚铁血红素氧化酶－1免疫组化染色和ATP酶活性测定，同时行肝左叶和尾状叶切除，观察肝切除前，肝切除后1d,2d,3d和第5d肝功能指标GOT，GPT和LDH变化，第5d测定肝再生指数。结果：缺血组缺血后24h，肝细胞亚铁血红素氧化酶－1染色强阳性，并由中央小静脉周围向汇管区逐渐减弱，两组肝ATP酶活性无差异；80％肝切除后第5d,缺血组血清GOT，GPT和LDH明显低于对照组（P＜0．05），肝功能恢复较对照组快，两组肝再生指数无明显差异（P＞0．05），结论：肝缺血15min后24h，肝细胞亚铁血红素氧化酶－1被大量诱导产生，短时间缺血可以改善肝切除术后肝功能，缺血组肝切除术后肝功能的迅速改善可能与亚铁血红素氧化酶－1的诱生有关。     

Change and role of heme oxygenase-1 in injured lungs following limb ischemia／reperfusion in rats

Lowerlimbischemiafollowedbyreperfusionisanimportantandcommonclinicalevent .Bothclinicalobservationandanimalexperimentindicatethatrestorationofbloodflowcansavethelimbsbutresultsinmultisystemorgandysfunctionevendeath .1Althoughthesystemicinflammationoflimbischemia/reperfusion (I/R )candamageanyorgan ,theonsetofthesyndromeisusuallyheraldedbythedevelopmentof pulmonarydysfunction .2 ,3Thiskindofpulmonarydysfunctionischaracterizedbyincreasedlungvascular permeabilityandpulmonaryhypertension ,whichis…     

血红素加氧酶-1诱导对鼠肝缺血再灌注损伤的保护作用

目的研究血红素加氧酶-1(heme oxygenase-1,HO-1)在鼠肝缺血再灌注损伤肝组织中的表达及其作用。方法建立小鼠部分肝脏热缺血再灌注损伤模型,36只清洁级Balb/C小鼠随机分为3组: 假手术组(S组)、缺血/再灌注损伤组(I/R组)、HO-1诱导剂氯化高铁血红素(hemin)预处理组(HM组)。免疫组化半定量分析肝组织HO-1蛋白的表达,检测血清AST和ALT,肝组织丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性,并观察肝组织的病理变化。结果与S组比较,I/R组HO-1蛋白表达显著增强,hemin预处理后,HO-1蛋白表达较I/R组增高(P<0．01)。I/R组AST,ALT活性和MDA的含量显著高于S组,而HM组均显著低于I/R组(P<0．01);I/R组SOD活性下降,而HM组显著高于I/R组(P<0．01)。HM组病理损伤程度明显轻于I/R组。结论 HO-1在鼠肝缺血再灌注损伤肝组织中表达上调,对肝脏具有保护效应。     

HO-1/CO系统在缺血/再灌注中的保护机制

缺血/再灌注(ischemia/reperfusion,I/R)损伤是心肌梗死等许多疾病的病理生理基础,也是手术、创伤、休克以及器官移植导致器官功能和结构损伤的原因之一.在已知的I/R损伤的众多病理机制中已经明确氧化应激产生的活性氧自由基和炎症反应具有重要的作用.血色素氧合酶-1(heme oxygenase-1,HO-1)能催化血色素降解生成胆绿素、一氧化碳(carbon monoxide,CO),并释放Fe2+离子.近年来的研究已经证明HO-1及其催化产物CO具有抗氧化应激和抗炎作用,在正规损伤中能够发挥对组织器官的保护作用.现就I/R损伤中HO-1/CO系统的保护作用进行综合阐述.     

血红素氧合酶-1在临床肝移植中肝脏保护作用的研究

目的 研究移植肝脏血红素氧合酶(HO-1)表达水平与缺血再灌注损伤和移植术后肝脏功能的关系.方法 研究28例人类临床原位肝脏移植,根据供肝血红素氧合酶(HO-1)表达的平均值将供肝分为两组:移植前供肝HO-1高表达组和移植前供肝HO-1低表达组.比较两组移植术后血浆AST、ALT水平、胆汁中胆盐含量以及术前术后HO-1 mRNA和蛋白表达情况.结果 再灌注后移植术前HO-1低表达组的HO-1 mRNA表达显著增加,而高表达组HO-1 mRNA表达却有所下降.肝脏移植后,术前HO-1低表达组与高表达组相比,血浆转氨酶显著降低,胆汁中胆盐含量明显高于后者.结论 移植术前HO-1低表达组供肝在再灌注过程中能够进一步诱导HO-1表达,与高表达组供肝相比其所遭受的缺血再灌注损伤较轻,移植术后肝脏功能较好.移植过程中HO-1表达的增强要比移植前HO-1高表达更具有细胞保护作用.免疫荧光染色证实枯否细胞是人类肝脏表达HO-1的主要部位.     

缺血再灌注肾损伤中血红素加氧酶-1的表达及其意义

肾脏缺血再灌注(IR)损伤与再灌注后氧应激反应的介导有关,而肾脏IR损伤的可逆性可能与肾脏内在的抗氧化保护机制相关犤1犦。血红素加氧酶-1(hemeoxygenase-1,HO-1)在肾脏的诱导性表达可能参与这一保护机制。本研究通过建立大鼠IR损伤模型,动态观察了IR大鼠肾脏HO-1在蛋白水平的时相表达,分析HO-1在肾脏缺血再灌注可逆性损伤中的作用;并通过lazaroid的干预,初步了解氧自由基清除剂对HO-1表达的影响。一、材料与方法1.模型建立与取样:SD雄鼠60只,先采血3ml,随机分为:(1)缺血再灌注组(IR组,n=20):切除右肾,夹闭左肾动脉60min后开启;(2)…     

血红素氧合酶-1基因转染对大鼠供肝缺血再灌注损伤的抗凋亡作用

目的 应用转染血红索氧合酶-1(HO-1)基因研究其在大鼠供肝缺血再灌损伤(IRI)中的抗凋亡作用.方法 将转染HO-1基因的腺病毒载体和空载体分别注入供体大鼠腹腔(n=8),36 h后取肝冷保存4 h行大鼠原位肝移植.缺血再灌注6 h检测肝功能、肝细胞凋亡率和肝组织HO-1、bcl-2、hel-xl和Caspase-3的表达.结果 (1)实验组的肝功能明显改善、肝细胞凋亡率显著低于对照组[(1.09±0.28)%比(8.30±1.08)%,P<0.01].(2)Western blot检测肝组织HO-1、bel-2和bcl-xl,灰度比值实验组显著高于对照组(HO-1:0.275±0.065比0.035±0.03;bcl-2:0.275±0.025比0.06±0.07;bcl-xl:(0.099±0.041比0.064±0.064,P<0.01),而Caspase-3则显著低于对照组(0.08±0.04比0.21±0.09,P<0.01).结论 HO-1在供肝IRI中通过上调bel-2、bel-xl和下调Caspase-3对供肝有显著的抗凋亡保护作用.     

缺血或药物预处理对大鼠供肝缺血再灌注损伤的抑制作用

目的　探讨缺血预处理 (IPC)或阿霉素预处理 (DPC ,模拟IPC)对大鼠供肝延迟性保护作用的发生机制。方法　将供鼠分为 3组。IPC组 :供鼠采用肝脏预先缺血 10min后再开放 ;DPC组 :供鼠经静脉注射阿霉素 (1mg/kg体重 ) ;对照组 :供鼠用等量生理盐水注射。观察各组预处理后血红素氧化酶 1(HO 1)和热休克蛋白 70 (HSP70 )含量 ;建立上述各组大鼠原位肝移植模型 ,并设假手术对照组 ,观察肝移植后各组对供肝缺血再灌注损伤的影响。结果　IPC组HO 1、HSP70含量分别于预处理 12h和 2 4h达到高峰 ;IPC和DPC组预处理 2 4h ,诱导的HSP70、HO 1含量差异无显著性 (P >0 .0 5 )。对照组肝移植后 6h ,肝组织中ICAM 1mRNA表达和内皮细胞ICAM 1分子表达明显增强 ,髓过氧化物酶 (MPO)活性增高 ,血清中天冬氨酸转氨酶 (AST)、丙氨酸转氨酶 (ALT)、乳酸脱氢酶 (LDH)及肝组织湿重 /干重 (W/D)水平明显升高 ,和假手术组相比 ,差异有显著性 (P <0 .0 1)。IPC或DPC组肝移植后减弱了ICAM 1mRNA和蛋白表达及MPO活性 ,AST、ALT、LDH及W/D的水平亦明显降低 ,与对照组比较 ,差异有显著性 (P <0 .0 5 )。结论　IPC的延迟保护作用是通过降低中性粒细胞的粘附浸润来实现的 ,这与IPC诱导生成HSP70和HO 1有关。DPC可以模拟IPC的延迟性保护     

阿霉素预处理替代缺血预处理提供鼠肝缺血耐受力的实验研究

目的 探讨缺血预处理（IPC）延迟保护作用的发生机制以及应用阿霉素预处理（DPC）是否可以模拟IPC的延迟保护作用。方法 建立大鼠部分肝脏热缺血再灌注模型。IPC组采用肝脏缺血10min，再灌注10in，DPC组经静脉注射阿霉素（1mg/kg体重），对照组等量生理盐水注射。肝组织HSP70和HO－1蛋白和血清TNF－α、IL－10浓度分别采用Western blot法和ELISA法测定。结果 IPC后HO－1和HSP70含量分别于12h和24h达到高峰；IPC和DPC后24h诱导HSP70、HO－1的量无显著差异（P＞0.05）。对照组缺血再灌注后3h血清中TNF－α、AST、ALT、LDH及W／D（湿重／干重）的水平明显升高，而IL－10的含量降低，和假手术组相比差异显著（P＜0.01）；IPC或DPC后降低了TNF－α的释放和AST、ALT、LDH及W／D的水平，提高了IL－10的含量，和对照组相比差异显著（P＜0.01）。结论 IPC的延迟保护作用与HSP70和HO－1的诱导生成有关，DPC可以模拟IPC的延尺性保护作用，诱导HSP70和HO－1的产生。     

血红素氧合酶-1对大鼠肾缺血再灌注损伤的保护作用

目的　探讨钴卟啉 (CoPP)诱导的血红素氧合酶 (HO) 1高表达对大鼠肾缺血再灌注损伤 (IRI)的保护作用。方法　建立大鼠肾缺血再灌注损伤模型 ,随机将动物分为假手术组 ,对照组和实验组。动态检测血尿素氮 (BUN)、肌酐 (Cr)、超氧化物岐化酶 (SOD)、丙二醛 (MDA)的含量以及进行肾组织光镜形态学观察和酶联免疫吸附试验 (ELISA)和Westernblot分析HO 1。结果　对照组BUN、Cr升高 ,SOD下降 ,MDA升高 ,HO 1中度提高 (14 4.5± 13 .6) ,肾组织结构紊乱。实验组除HO 1含量大幅提高外 (62 9.4± 78.9) ,尚能显著逆转上述改变 ,两组间差异具有统计学意义 (P <0 .0 5 )。结论　CoPP预处理诱导HO 1在肾缺血之前高表达可通过清除氧自由基 (OFRs)而减轻大鼠肾IRI。     

内源性一氧化碳在大鼠肢体缺血再灌注致远隔多脏器氧化性损伤中的作用

目的　探讨内源性一氧化碳 (CO)在大鼠肢体缺血再灌注 (I/ R)致远隔多器官氧化性损伤中的作用机制。方法　将 6 4只大鼠随机分为 4组 :假手术 (Sham )组 ;Sham 特异性血红素氧化酶阻断剂—锌原卟啉 (Zn PP)组 ;肢体缺血 2小时和再灌注 4小时 (I/ R)组 ;I/ R Zn PP组。测定各组心、肺、肝和肾组织匀浆中丙二醛 (MDA )含量、超氧化物歧化酶 (SOD)活性及血液内碳氧血红蛋白 (COHb)的变化 ,观察动物 2 4小时存活率。结果　与 Sham组相比 ,I/ R组各脏器 MDA含量及血液内 COHb水平均显著增高 ,组织中 SOD活性和动物 2 4小时存活率显著降低 ,有统计学意义(P<0 .0 5 ) ;I/ R Zn PP组与 I/ R组相比各脏器 MDA含量进一步增高 ,血液内 COHb水平、组织中 SOD活性和动物的2 4小时存活率显著降低 ,也有统计学意义 (P<0 .0 5 )。结论　肢体缺血再灌注可导致多器官的氧化性损伤 ,并使 CO产生增多 ,后者在大鼠抗缺血再灌注所致的远隔多器官损伤中具有重要作用。     

上调肝脏HO-1抑制肥大细胞脱颗粒减轻大鼠肝脏缺血再灌注损伤

目的 探索HO-1对肝脏缺血再灌注损伤中肥大细胞脱颗粒的影响。方法 将20只SD大鼠随机分成4组：假手术组（Sham组）,缺血再灌注损伤组（I/RI组）,HO-1诱导剂钴原卟啉组(CoPP组,术前24h给予CoPP,5 mg/kg)及HO-1抑制剂锌原卟啉组(ZnPP组,术前24h给予ZnPP,20 mg/kg)。建立大鼠缺血再灌注损伤模型,各组于再灌注后2h收集标本。RT-PCR检测肝脏组织HO-1 mRNA表达,Western blot检测肝脏组织HO-1蛋白表达;测定血清中ALT、AST水平;肝脏组织甲苯胺蓝染色检测肥大细胞脱颗粒数量,HE染色评价肝脏组织损伤情况。结果 与Sham组相比,I/RI组、CoPP组、ZnPP组大鼠组织HO-1 RNA和蛋白表达增加,血清ALT、AST水平升高,肥大细胞脱颗粒数量增多,肝脏细胞损伤加重。CoPP组与I/RI组相比,HO-1 mRNA和蛋白表达增加,血清ALT、AST水平减低,肥大细胞脱颗粒数量减少,肝细胞损伤减轻。ZnPP组与I/RI组相比,HO-1 mRNA和蛋白表达减少,血清ALT、AST水平升高,肥大细胞脱颗粒数量增多、肝细胞损伤严重。组间比较差异具有统计学意义(P＜0.05)。结论 HO-1过表达能减轻肝脏I/RI,其机制可能与抑制肝脏组织中肥大细胞脱颗粒有关。     

辛伐他汀预处理对肢体缺血再灌注诱发肺损伤大鼠肺组织血红素加氧酶-1表达的影响

目的 评价辛伐他汀预处理对肢体缺血再灌注诱发肺损伤大鼠肺组织血红素加氧酶-1(HO-1)表达的影响.方法 成年雄性SD大鼠48只,体重250～300 g,采用随机数字表法,将大鼠随机分为6组(n=8):假手术组(S组)、肢体缺血再灌注组(IR组)、辛伐他汀1、5、10 mg/kg组(S1组、S2组、S3组)和辛伐他汀对照组(SC组).采用夹闭股动脉2 h,再灌注3 h的方法制备肢体缺血再灌注模型.S组:仅分离股动脉和股静脉,不夹闭;IR组:制备肢体缺血再灌注模型;S1组、S2组、S3组:分别将辛伐他汀1、5、10 mg/kg溶于1 ml蒸馏水,于每13清晨灌胃1次,连续灌胃3 d后制备肢体缺血再灌注模型;SC组:辛伐他汀10 mg/kg溶于1 ml蒸馏水,于每日清晨灌胃1次,连续灌胃3 d.再灌注3 h时取颈动脉血样,行血气分析,记录PaO2和PaCO2,随后处死大鼠,取肺组织,观察病理学结果,计算湿重/干重比(W/D比),测定SOD活性,计数PMN,测定HO-1 mRNA及其蛋白的表达水平.结果 与S组比较,IR组PaO2及PaCO2降低,IR组、S1组和S2组肺组织W/D比和PMN计数升高,SOD活性降低(P＜0.05),S3组和SC组上述指标差异无统计学意义(P＞0.05),IR组、S1组、S2组、S3组和SC 组肺组织H0-1 mRNA及其蛋白表达上调(P＜0.01);与IR组比较,S1组、S2组和S3组PaO2、PaCO2及肺组织SOD活性升高,肺组织W/D比和PMN计数降低,肺组织HO-1 mRNA及其蛋白表达上调(P＜0.05或0.01);S1组、S2组和S3组肺组织WID比和PMN计数依次降低,SOD活性依次升高,HO-1 mRNA及其蛋白表达依次上调(P＜0.05或0.01).S1组、S2组和S3组肺组织病理性损伤较IR组减轻.结论 辛伐他汀预处理可上调肢体缺血再灌注大鼠肺组织HO-1的表达,从而产生肺保护作用,且呈剂量依赖性.

Abstract：

Objective To investigate the effects of simvastatin preconditioning on the pulmonary heme oxygenase-1 (HO-1) expression in rats with lung injury induced by ischemia-reperfusion (I/R) of hind limbs. Methods Forty-eight adult male SD rats weighing 250-300 g were randomly divided into 6 groups ( n = 8 each) : sham operation group (group S) ; I/R group; I/R + simvastatin 1,5, 10 mg/kg groups (S1 , S2, S3 groups) ; simvastatin control group (group SC) . I/R of hind limbs was produced by occlusion of bilateral femoral arteries for 2 h followed by 3 h reperfusion. Croups S1 , S2 , S3 received simvastatin 1, 5, 10 mg/kg respectively via an oro-gastric tube for 3 days before I/R. Group SC received simvastatin 10 mg/kg via an oro-gastric tube for 3 days. Arterial blood samples were taken at 3 h of reperfusion for blood gas analysis and PaO2 and PaCO2 were recorded. The animals were then sacrificed and the lungs removed immediately for pathologic examination and determination of the wet/dry lung weight ratio (W/D ratio), superoxide dismutase (SOD) activity and polymorphonuclear neutrophil (PMN) count . Hie expression of HO-1 mRNA and protein in lung tissues was detected using RT-PCR and Western blot analysis respectively.Results Alveolar edema, localized pulmonary atelectasis and large amount of PMN infiltration were found in I/R group and were ameliorated in S1, S2, S3 groups. Compared with group S, PaO2 and PaCO2 were significantly decreased in I/R group, W/D ratio and PMN count were increased and SOD activity was significantly decreased in I/R, S1 , S2 groups, and expression of HO-1 mRNA and protein was up-regulated in the other five groups ( P ＜ 0.05). PaO2, PaCO2 and SOD activity were significantly increased, W/D ratio and PMN count were significantly decreased, and HO-1 mRNA and protein expression was up-regulated in S1, S2 and S3 groups as compared with I/R group ( P ＜ 0.05 or 0.01). W/D ratio and PMN count were gradually decreased, SOD activity was gradually increased, and HO-1 mRNA and protein expression was gradually up-regulated in S1, S2 and S3 groups. Conclusion Simvastatin preconditioning has protective effect against lung injury induced by I/R of hind limbs in rats through up-regulation of HO-1 expression in the lung tissues and in a dose-dependent manner.     

Transient limb ischemia induces remote preconditioning in liver among rats: the protective role of heme oxygenase-1

BACKGROUND: We have reported the protective role of heme oxygenase-1 (HO-1) in the mechanism of hypoxic preconditioning. We wish to investigate the role of HO-1 in remote preconditioning (RP) against hepatic ischemia/reperfusion (I/R) injury in rats. METHODS: The remote preconditioning was produced by four cycles of 10-min ischemia-reperfusion of the hind limb of rats. Partial hepatic ischemia was produced in the left lobes for 45 min followed by 240 min of reperfusion. Zinc-protoporphyrin IX (ZnPP), a specific inhibitor of HO enzymatic activity, was intra-peritoneally injected 1 hr before the ischemia-reperfusion injury in separate groups of RP rats. Serum alanine transaminase (ALT) levels, expression of hepatic HO-1 protein and mRNA, immunohistochemical staining and HO enzymatic activity were measured. RESULTS: HO-1 was induced in the livers of rats 4 hr after the RP stimuli, and the overexpression persisted for 24 hr. Immunohistochemical staining demonstrated induction of HO-1 in the hepatocytes. The peripheral lymphocytes did not express HO-1 after RP. RP diminished the elevation of serum ALT levels 4 hr after I/R injury (283.7+/-167.4 U L) when compared with controls (1297.7+/-729.3 U L) and RP+ ZnPP pretreated groups (1429.9+/-750.9 U L). The heme oxygenase activity in treated rats also correlated these results (286.8+/-34.3 pmol mg protein hr for the RP group, 156.3+/-27.5 pmol mg protein hr for the RP+ ZnPP pretreated group, and 170.6+/-19.4 pmol mg protein hr for the control group, 144.8+/-7.8 pmol mg protein hr for the control+ ZnPP pretreated group). CONCLUSION: Our results indicated that the induction of HO-1 in remote preconditioning played a protective role against hepatic I/R injury.     

Contributions of heme oxygenase-1 in postconditioning-protected ischemia-reperfusion injury in rat liver transplantation

Background

Heme oxygenase-1 (HO-1), an oxidative stress-response gene up-regulated by various physiological and exogenous stimuli, has cytoprotective activities. Ischemic postconditioning (Postcon) can protect an organ from ischemia-reperfusion (I/R) injury. In the present study, we investigated the potential contributions of HO-1 to Postcon-dependent protection against I/R injury in rat liver transplantation models.

Materials and methods

Adult male Sprague-Dawley rats were randomly divided into four groups: sham group with laparotomy for liver exposure; I/R group with 24-hour cold ischemia of the donor liver; Postcon group with the same treatment as the I/R group plus ischemic Postcon; and zinc protoporphyrin (ZnPP HO-1 inhibitor) + Postcon group treated the same as the Postcon cohort with donors pretreated using ZnPP 24 hours before the I/R injury. We measured liver tissue and peripheral blood samples collected at 6 hours after reperfusion and serum transaminase levels, histopathology, liver tissue malondialdehyde (MDA) content, superoxide dismutase (SOD) activity and HO-1 expression in the liver.

Results

Postcon significantly diminished the elevation of serum transaminases levels after I/R injury when compared with I/R and ZnPP+Postcon groups. Postcon treated rats showed significantly lower MDA production and higher SOD activity. HO-1 was induced in rat livers exposed to Postcon; its levels were obviously overexpressed after 6 hours in Postcon rats. Inhibiting the expression of HO-1, negated the protective effects of Postcon.

Conclusions

Induction of HO-1 in the Postcon condition played a protective role against hepatic I/R injury and enhanced the early antioxidative activity. The protective effects of Postcon were significantly associated with greater intrahepatic HO-1 expression.     

Heme oxygenase-1 overexpression protects rat hearts from cold ischemia/reperfusion injury via an antiapoptotic pathway

BACKGROUND: Ischemia/reperfusion (I/R) injury is one of the most important causes of the early graft loss. We have shown that overexpression of heme oxygenase-1 (HO-1), an inducible heat shock protein 32, protects rat livers against I/R injury. We report on the cytoprotective effects of HO-1 in a rat cardiac I/R injury model, using cobalt protoporphyrin (CoPP) as HO-1 inducer and zinc protoporphyrin (ZnPP) as HO-1 inhibitor. METHODS: Three groups of Lewis rats were studied: group 1 control donors received phosphate-buffered saline 48 hr before the harvest; group 2 donors were pretreated with CoPP at -48 hr; and in group 3, donors received CoPP at -48 hr and ZnPP was given to recipients at reperfusion. Hearts were harvested, stored in University of Wisconsin solution (4 degrees C) for 24 hr, and then transplanted to syngeneic (Lewis) rats. RESULTS: Sixty percent of control grafts ceased their function in <15 min. In contrast, 80% of CoPP-pretreated grafts survived 14 days. All grafts stopped functioning within 24 hr after CoPP + ZnPP therapy. Cardiac HO-1 enzymatic activity and protein expression correlated with beneficial effects of CoPP and deleterious effects of adjunctive ZnPP treatment. Markedly less apoptotic (TUNEL+) myocyte/endothelial cells could be detected in CoPP cardiac grafts, as compared with controls. The expression of antiapoptotic (Bcl-2/Bag-1) proteins was up-regulated in the CoPP group. CONCLUSION: HO-1 overexpression provides potent protection against cold I/R injury in a stringent rat cardiac model. This effect depends, at least in part, on HO-1-mediated up-regulation of a host antiapoptotic mechanism, especially in the early postreperfusion period.     

Protective effects of pretreatment with Radix Paeoniae Rubra on acute lung injury induced by intestinal ischemia/reperfusion in rats

Objective： To investigate the effect of pretreatment with Radix Paeoniae Rubra （RPR） on acute lung injury induced by intestinal ischemia/reperfusion in rats and its protective mechanism.
Methods： Thirty-two Wistar rats were randomly divided into four groups： Sham-operation group, ischemla/ reperfusion group （I/R group ）, RPR-pretreatment group and hemin group. The model of intestinal ischemia/ reperfusion was established by clamping the superior mesenteric artery for 1 hour followed by 2-hour reperfusion. The effect of RPR on the expression of heme oxygenase-1 （HO-1） in lung tissues was detected by immunohistochemistry and morphometry computer image analysis. Arterial blood gas analysis, lung permeability index, malondialdehyde （MDA） and superoxide dismutase （SOD） contents in lungs were measured. The histological changes of lung tissue were observed under light microscope.
Resalts： The expression of HO-1 in RPR-pretreatment group and hemin group was obviously higher than that in sham-operation group and I/R group （ P 〈 0.01 ）. The level of MDA and lung permeability index in RPR-pretreatment and hemin group were significantly lower than those in I/R group （P〈0.01 or P〈0.05）, while the activity of SOD in RPR-pretreatment and hemin group was obviously higher than that in I/R group （P〈0.01）. Under light microscope, the pathologic changes induced by I/R were significantly attenuated by RPR.
Conclusion： Intestinal ischemia/reperfusion may result in acute lung injury and pretreatment with RPR injection can attenuate the injury. The protective effect of RPR on the acute lung injury is related to its property of inducing HO-1 expression and inhibiting lipid peroxidation.     

小剂量氯胺酮预处理对大鼠肠缺血再灌注损伤的影响

目的 探讨小剂量氯胺酮预处理对大鼠肠缺血再灌注损伤的影响.方法 清洁级健康雄性SD大鼠48只,体重230～270 g,随机分为6组(n=8):假手术组(S组)、氯胺酮+假手术组(KS组)、肠缺血再灌注组(I/R组)、氯胺酮预处理组(K组)、锌原卟啉Ⅸ+氯胺酮预处理组(KZ组)和锌原卟啉Ⅸ组(Z组).采用夹闭肠系膜上动脉根部1 h后再灌注的方法 制备肠缺血再灌注模型.于麻醉前30 min时,S组腹腔注射生理盐水2 ml,K组和KS组均腹腔注射氯胺酮10 mg/kg,KZ组依次腹腔注射氯胺酮10 ms/kg和锌原卟啉Ⅸ5 mg/kg,Z组腹腔注射锌原卟啉Ⅸ5 mg/kg.S组、KS组仅分离肠系膜上动脉,不结扎.于再灌注6 h时处死大鼠,取肠组织测定丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性、血红素加氧酶-1(HO-1)及诱导型一氧化氮合酶(iNOS)的表达,光镜下观察肠组织病理学结果 并采用Chiu评分评价损伤程度.结果 与S组比较,I/R组、KZ组和Z组肠组织MDA含量升高,SOD活性降低,K组MDA含量升高(P<0.05或0.01),SOD活性差异无统计学意义(P>0.05),I/R组、K组、KZ组和Z组肠组织HO-1和iNOS表达上调(P<0.05或0.01),肠组织病理学损伤加重;与I/R组比较,K组肠组织MDA含量降低,SOD活性升高,肠组织HO-1表达上调,iNOS表达下调(P<0.05),肠组织病理学损伤减轻,KZ组和Z组以上指标差异无统计学意义(P>0.05).结论 小剂量氯胺酮预处理可减轻大鼠肠缺血再灌注损伤,可能与氯胺酮上调肠组织HO-1表达,下调iNOS表达有关.     

缺血预处理对大鼠缺血再灌注心肌HIF-1α和HO-1的影响

目的 探讨缺血预处理对大鼠缺血再灌注心肌低氧诱导因子1α(HIF-1α)和血红素加氧酶1(HO-1)的影响.方法 健康雄性SD大鼠48只,体重220～280 g,随机分为4组(n=12):假手术组(S组)、缺血再灌注组(IR组)、缺血预处理+缺血再灌注组(IP组)和缺血预处理+缺血再灌注+HO-1抑制剂组(HI组).采用结扎左冠状动脉前降支30 min再灌注120 min的方法建立心肌缺血再灌注模型.S组仅在冠状动脉下穿线;IP组于缺血前采用结扎/放松左冠状动脉前降支各5 min,重复3次的方法行缺血预处理;HI组于缺血预处理前1 d腹腔注射锌原卟啉Ⅸ 10 ms/ks,其余同IP组.于再灌注结束时测定心肌HIF-1α、HO-1的mRNA和蛋白表达、HO-1活性、SOD活性及MDA含量,计算心肌梗死面积,取动脉血样测定血清TNF-α和IL-6的浓度.结果 与S组比较,IR组、IP组和HI组心肌SOD活性降低,MDA含量升高,血清TNF-α和IL-6的浓度升高(P＜0.01);与IR组比较,IP组心肌SOD活性升高,MDA含量降低,血清TNF-α和IL-6浓度降低,心肌HIF-1α和HO-1的mRNA和蛋白表达上调,HO-1活性升高,心肌梗死面积减小(P＜0.01);与IP组比较,HI组心肌SOD活性降低,MDA含量升高,血清TNF-α和IL6浓度升高,心肌HO-1的mRNA和蛋白表达下调,HO-1活性降低,心肌梗死面积增加(P＜0.05或0.01),心肌HIF-1α的mBNA和蛋白表达差异无统计学意义(P＞0.05).结论 缺血预处理减轻大鼠心肌缺血再灌注损伤的机制与HIF-1α诱导HO-1活性增强有关.