肾脏缺血再灌注损伤的基因表达变化的进展

缺血再灌注损伤是指缺血组织或器官重获血流灌注或氧供后 ,对组织和器官所产生的损伤作用 ,涉及氧自由基的产生 ,中性粒细胞损伤区浸润等多重病理生理改变 ,机制十分复杂。细胞膜损伤、细胞内钙增加、高能磷酸酯的耗竭 ,线粒体失功 ,渗透压改变 ,细胞内 ｐＨ下降及氧自由基的生成 ,可引起细胞的凋亡和坏死 ,是损伤细胞的典型改变[1] 。损伤开始后 ,机体可通过基因调控的增生性反应和拮抗损伤机制 ,对损伤组织和器官进行最大限度的修复。一、应激和基因表达缺血再灌注损伤对机体是一种应激反应。应激时细胞对外界环境变化需要做出即时反应以…     

肢体缺血后处理和肾脏缺血后处理对大鼠肾脏缺血-再灌注损伤的影响

目的 探讨肢体缺血后处理和肾脏缺血后处理对大鼠肾脏缺血-再灌注(I-R)损伤的影响.方法 24只大鼠随机均分为假手术组(S组)、缺血-再灌注组(I-R组)、左下肢缺血后处理组(LIP组)及肾脏缺血后处理组(RIP组).S组仅对左肾动脉进行游离;I-R组:夹闭左肾动脉45 min后松开,左肾再灌注6 h;LIP组在左肾复灌前6 min时左股动脉夹闭5 min;RIP组在左肾缺血45min后灌注10 s,停灌10 s,反复6次;检测复灌6 h时血清肌酐(Cr)、血尿素氮(BUN);光镜下观察肾组织病理改变,TUNEL法检测肾组织中凋亡细胞并计算凋亡指数(AI);免疫组化法检测肾组织Fas、Caspase-3表达;电镜下观察肾单位超微结构改变.结果 与S组比较,其他三组大鼠BUN、Cr浓度升高(P<0.01)、肾组织病理改变明显、肾组织Fas、Caspase-3阳性指数和AI增加(P<0.01).与I-R组比较,LIP、RIP组大鼠BUN、Cr浓度降低(P<0.01),肾组织Fas、Caspase-3阳性指数和AI降低(P<0.01).RIP组AI明显低于LIP组(P<0.05).结论 在肾脏I-R损伤的病理过程中,肾小管上皮细胞凋亡可以由胞膜上的Fas被激活而最终导致靶细胞凋亡;两种后处理都可以抑制肾小管上皮细胞凋亡,减轻I-R损伤.     

缺血再灌注损伤与细胞凋亡

目的 研究缺血再灌注过程中细胞凋亡现象的发生及其相关机理。方法 采用文献回顾的方法对缺血再灌注期间细胞凋亡现象的发生及其相关机理进行综述。结果 多种脏器、组织历经缺血再灌注后均发现有细胞凋亡现象，缺血再灌注期间影响细胞凋亡的因素有多种，如缺血、缺氧、氧自由基、细胞内钙超载、多种细胞因子等，而细胞凋亡的调控与多种基因的调控有关，如bcl-2家族、caspase家族及核因子NF－κB等。结论 细胞凋亡是脏器、组织在缺血再灌注期间的一种普遍现象，它受多种因素的影响和调节。     

肾脏缺血／再灌注损伤中肾小管上皮细胞凋亡机制的研究现状

肾脏缺血／再灌注(I／R)损伤是临床上导致急性肾功能衰竭的常见原因，肾小管上皮凋亡是其重要的发病机制之一。目前肾脏I／R损伤中肾小管上皮细胞凋亡的机制尚未完全阐明，因而缺乏有效的治疗措施。本文就此方面的研究现状作一综述。     

缺血预处理对肾脏缺血再灌注损伤保护作用的研究进展

肾缺血再灌注损伤导致急性缺血性肾衰竭在临床上十分常见.研究显示缺血预处理对肾缺血再灌注损伤具有保护作用.近年来关于肾缺血预处理作用机制的报道较多,本文就缺血预处理对肾缺血再灌注损伤保护作用的研究现状作一综述.     

大鼠缺血再灌注肾脏原癌基因表达的研究

已有研究表明,细胞损伤后的修复与原癌基因的适当调节有关[Kidney Int,1991.39:401]。为了解急性缺血性肾损伤分子调控水平的变化,我们应用Northern杂交技术,在大鼠缺血再灌注肾组织中研究了几种原癌基因的表达,以探讨原癌基因在缺血肾脏损伤修复中的可能作用。 一、材料与方法 选用纯种SD雄性大鼠5只,4月龄,体重250～300g。实验组12只,腹腔麻醉下行右肾切除,左肾动脉夹闭45分钟,分别于再灌注1、4、8、24小时摘取左肾剥除包膜及肾上腺,液氮冷冻待用。对     

活血清下法对小肠缺血再灌注大鼠小肠细胞凋亡的影响

目的：研究活血清下法对小肠缺血再灌注大鼠小肠细胞凋亡的影响。方法：将Wistar大鼠分为6组：正常对照组（NOR）、模型对照组（CON）、抗生素组（ANT）、加味小承气汤组（JQXCQ）、复方丹参方组（FDS）、活血清下汤组（HXQX）。分别观察术后6h，24h，72h回肠粘膜上皮细胞、固有层细胞、淋巴滤泡凋亡指数（apoptosis index，AI）及血清内毒素水平。结果：模型对照组术后6h回肠粘膜上皮细胞、固有层细胞、淋巴滤泡凋亡指数及血清内毒素水平均显著高于正常对照组，活血清下汤组上述指标较模型组显著改善。结论：活血清下法能有效地减少缺血再灌注所致肠粘膜上皮细胞和淋巴细胞的凋亡，保护肠屏障。     

大鼠肾脏缺血-再灌注后诱导型热休克蛋白70的基因表达

目的：探讨肾脏组织在缺血－再灌注损伤过程中诱导型热休克蛋白70（iHSP70)的基因表达。方法：运用狭缝杂交印迹法，半定量测定Wistar大鼠肾脏在原位缺血－再灌注后皮层部和乳头部组织中iHSP 70 mRNA的水平。结果：在单纯缺血实验中，缺血10、30和60min三组，肾脏皮层部iHSP70基因的表达与正常无缺血对照组差异无显著性；在缺血－再灌注实验中，肾脏皮层部和乳头部肾组织iHSP70基因表达在缺血10min、再灌注2－72h各组与正常对照组比较，均未见明显的变化，而在缺血30和60min后再灌注2－72h各组中，4－48h各组均显著高于对照组；再灌注后72h与对照组差异无显著性。对肾脏皮层部和乳头部的峰值表达分析，乳头部大于皮层部。在再灌注时间为轴线的表达趋势可以看出，缺血30和60min的表达类似。结论：在肾脏缺血再灌注过程中，iHSP70基因呈现快速的一过性表达；一定程度的缺血损伤，是诱导肾脏在再灌注过程中iHSP70基因表达的前提条件，但肾脏缺血损伤的程度并不影响其iHSP70基因表达的强度；在缺血－再灌注损伤中，肾脏不同解部部位诱导iHSP70基因表达的强度不同，乳头部强于皮层部。     

大鼠骨骼肌缺血再灌注损伤的细胞凋亡及相关基因表达

目的研究缺血性损伤和缺血再灌注损伤的发生情况和病理改变，探讨细胞凋亡及相关基因p53、p21、Bax、Bcl-2的表达规律。方法建立大鼠后肢缺血和缺血再灌注实验模型，光镜下观察缺血和缺血再灌注早期的骨骼肌组织病理学变化，检测缺血和缺血再灌注过程中细胞凋亡现象的发生及相关基因p53、p21、Bax、Bcl-2的表达。结果缺血5h的大鼠骨骼肌全部存活，而缺血9h者未获存活。缺血和缺血再灌注损伤引起骨骼肌细胞水肿、坏死和细胞凋亡，并于再灌注过程观察到微循环障碍和中性粒细胞趋化浸润现象。缺血7h细胞凋亡率最高，相关基因p53、p21、Bax表达与缺血时间成正比，而Bcl-2表达与缺血时间成反比。结论细胞凋亡是缺血和缺血再灌注损伤的重要病理学改变。微循环障碍和中性粒细胞趋化浸润是缺血再灌注损伤的重要原因之一。相关基因表达与凋亡的发生关系密切。     

大鼠小肠缺血再灌注后肾脏损伤

通过对２０只大鼠小肠缺血再灌注模型和肾组织中脂质过氧化物的测定,并结合病理改变,以探讨小肠缺血再灌注后肾损伤的病理机制。结果表明：大鼠小肠缺血再灌注后,血脂质过氧化物明显升高,同时关浆内脂质过氧物明显高于对照组。提示小肠缺血再灌注后肾组织细胞确有明显损伤,其中氧自由基对肾组织的破坏可能是肾脏病理生理改变的主要因素。     

缺血再灌流肾组织内皮素—1及其受体基因表达的实验研究

为了探究内皮素１（ＥＴ１）对肾功能的影响和作用方式，采用斑点杂交和原位杂交方法对大鼠缺血６０分钟再灌注肾组织ＥＴ１及其受体亚型（ＥＴＡ、ＥＴＢ）的基因表达进行了研究。结果发现：再灌流１小时，ＥＴ１、ＥＴＡ、ＥＴＢｍＲＮＡ均明显升高；再灌流２４小时仍维持较高水平。ＥＴ１和ＥＴＡｍＲＮＡ杂交信号再灌流３小时达高峰。ＥＴ１ｍＲＮＡ主要分布肾皮质小血管内皮细胞、髓质肾小管和集合管，ＥＴＡ受体ｍＲＮＡ则分布于上述小血管的平滑肌细胞。ＥＴＢ受体ｍＲＮＡ于再灌流６小时达高峰，主要分布髓质肾小管、集合管。说明缺血再灌流肾内皮素受体亚型上调在皮质以ＥＴＡ为主，在髓质以ＥＴＢ为主，分别与增强表达的ＥＴ１结合导致肾皮质缺血和水钠代谢异常。     

Silymarin attenuates the renal ischemia/reperfusion injury-induced morphological changes in the rat kidney

OBJECTIVES: Renal ischemia/reperfusion (I/R) injury is associated with increased mortality and morbidity rates due to acute renal failure (ARF). Oxidative stress induced with renal I/R injury directly affects glomerular and tubular epithelium through reactive oxygen species. Several studies have been directed to the treatment of renal I/R injury. The aim of this study was to test the attenuation with silymarin (SM) treatment of renal I/R injury-induced morphological changes in the rat kidney. METHODS: A total of 32 adult male Sprague-Dawley rats were evaluated in four groups. Group I (sham), Group II (renal I/R), Group III (renal I/R injury + SM 50 mg per kg) and Group IV (renal I/R injury + SM 100 mg per kg) were designed to evaluate the dose-dependent effects of SM on the morphological changes of renal I/R injury. Renal I/R injury were induced with left renal pedicle occlusion for 45 min followed with reperfusion for 6 h under anesthesia. After induction of I/R injury, left nephrectomies were performed for histopathological examinations. RESULTS: After renal I/R injury, significant tubular dilatation, tubular vacuolization, pelvic inflammation, interstitial inflammation, perirenal adipose infiltration, tubular necrosis and glomerular necrosis (cortical necrosis) were observed. However, even with low dose SM in Group III (50 mg per kg SM), histopathological changes due to I/R injury were prevented. CONCLUSIONS: The results of this study have demonstrated that SM significantly prevents renal I/R injury-induced renal tubular changes in the rat. SM in 50 mg/kg was observed to be sufficient to significantly prevent renal tubular necrosis. Further, to our literature knowledge, this is the first specific study to demonstrate the preventive effect of SM on renal I/R injury.     

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。     

大鼠肾冷缺血再灌注损伤模型的建立

目的 建立大鼠肾冷缺血再灌注损伤(IRI)的模型.方法 封闭群SD大鼠24只,随机分为2组(n=12):A组(对照组),B组(实验组).A组切除右肾并游离左肾蒂,60 min后关闭腹腔切口.B组采用冷缺血再灌注模型,主要步骤:(1)冷灌注:右肾动脉插管对左肾原位灌注.通过右肾静脉插管将灌注液引流出体外,完成冷灌注后切除右肾,阻断左肾蒂.(2)冷缺血保存:将已充分游离的左肾牵至腹腔外,在自制保存袋中冷保存.(3)再灌注:60min后,去除保存袋,开放血流,再灌注左肾,左肾复位,缝合切口;2组大鼠均在术后24 h再次手术切除左.肾.肾组织进行光镜、电镜形态学检查,检测肾组织匀浆中超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量,术前与术后24 h取血标本进行测定血尿素氮(BUN)、肌酐(Cr)评估肾功能.结果 (1)形态学检查(光镜与电镜超微结构):A组肾脏组织形态结构正常,B组损伤表现明显;(2)A组手术前后比较血浆BUN、Cr测定值差异均无统计学意义(P＞0.05).IR后的B组均高于术前,差异有统计学意义(P＜0.05);(3)IRI后A组肾组织匀浆SOD活力高于B组(P＜0.05),A组肾组织匀浆MDA含量测定值低于B组,差异有统计学意义(P＜0.05).结论 建立的模型要求条件简单、易行,可用于肾移植冷缺血再灌注损伤相关的研究;

Abstract：

Objective In this study,for studying IRI in kidney transplantation. ,we established the models of cold ischemia and reperfusion injury in rats. Methods Twenty four SD rats were randomly assigned to two groups:control (A) ,and experimental (B) group. Group A was only removed the right kidney. Cold ischemia reperfusion was performed as the follow-listed model in Group B. The main process of the model: ( 1) Perfusing left kidney: after resected the right kidney of the rat, one pipe was put in the remainder right renal artery to perfuse the left kidney. The perfusion flowed out through another pipe in the right renal vein. The blood vessels of left kidney were clipped after cold perfusion. (2) Cold ischemic conservancy : the operation table was leant to left side, and the left kidney was taken out of abdominal cavity then stored in a cold bag which was full of ice and water,but the vessels of that were intact. (3) Reperfusing left kidney: after 60 minutes, the clip was removed. Left kidneys of all rats in two groups were removed to be detected. Structure of the kidney was evaluated by light microscopy and electronic microscopy. Superoxide dismutase ( SOD) activity and malondialdehyde ( MDA) content in the renal tissues was examined,and the renal function was also assessed by determining the levels of blood urea nitrogen ( BUN) and serum creatinine (CR) before and 24 hours after operation. Results (1) Morphologic change (hematoxylin-eosin staining) :A normal morphology was observed by light microscopy and electon microscopy in group A.Significant injury was detected in group B. (2 ) In group A, there was not significant difference about BUN and CR between before and after operation (P ＞0. 05) ,but in Group B,those increased significantly at 24 hour after operation (P ＜0. 05). (3) Activity of SOD in renal tissues in group A was higher than those in group B (P ＜ 0. 05 ) , meanwhile, Content of MDA in group A was lower than those in group B ( P ＜0. 05 ).Conclusion The rat renal cold ischemia reperfusion model we established is feasible regardless of experimental conditions, and can be studied as the events following IRI in kidney transplantation.     

缺血再灌流肾组织内皮素—1动态变化的实验研究

在大鼠肾缺血６０分钟再灌注的模型上观察不同时相肾静脉血、肾皮质、外髓和内髓的内皮素１（ＥＴ１）浓度变化，肾组织ＥＴ１光镜和电镜免疫组织化学变化。结果发现：缺血再灌流肾组织ＥＴ１基因表达及分泌明显增强，主要分布在血管内皮细胞及平滑肌细胞、系膜细胞、肾小管上皮细胞。其分布特点与细胞类型和活性有关。本实验结果提示了缺血再灌注肾内ＥＴ１的变化规律。     

1,6二磷酸果糖对大鼠脑缺血-再灌注损伤后凋亡细胞及p38和Ref-1的研究

目的探讨1,6二磷酸果糖（FDP）对大鼠脑缺血-再灌注（I-R）损伤的作用及其机制。方法雄性SD大鼠90只,随机分为果糖治疗（F）组、脑缺血（I）组和假手术对照（c）组,每组30只。I组和F组大鼠在凝断双侧椎动脉24h后夹闭双侧颈总动脉,5min后重新开放,制作全脑缺血模型。F组再灌注开始时静脉注射FDP 1．5ml／kg,I组及C组分别静脉注射生理盐水1．5ml／kg。各组在再灌注后2、6、12、24、48、72h时取标本,制备脑组织病理切片,采用免疫组织化学染色方法测定p38蛋白和Ref-1蛋白的表达,TUNEL检测凋亡细胞数目。结果与C组比较,I组凋亡细胞显著增多（P〈0．05）;与C组比较,I组在再灌注后各时点p38蛋白、Ref-1蛋白表达均显著增强（P〈0．05）,F组较C组表达增强但较I组表达显著减弱（P〈0．05）。结论FDP对全脑I-R损伤有保护作用,其机理可能与其参与细胞信号转导减弱p38、Ref-1蛋白表达强度有关。     

缺血后处理减轻肠缺血再灌注引起的肝损伤的机制研究

目的：探讨缺血后处理减轻肠缺血再灌注引起的肝损伤的作用机制,为外科防治缺血再灌注损伤提供策略。方法将36只SD大鼠随机分为假手术组（SO组,仅手术显露肠系膜上动脉）、缺血再灌注组（IR组,阻断肠系膜上动脉60min,再灌注120min）、缺血后处理组（IP组,阻断肠系膜上动脉60min后行3个循环的灌注30s/阻断30s,再持续灌注117min）,每组12只。建立模型2h后采集各组大鼠动、静脉血及部分小肠、肝组织,检测血肿瘤坏死因子α（TNF-α）、白细胞介素10（IL-10）、丙氨酸氨基转氨酶（ALT）、天门冬氨酸氨基转移酶（AST）水平,测定血清及肝组织内丙二醛（MDA）、髓过氧化酶（MPO）水平,光学显微镜下观察小肠及肝脏病理学改变,免疫组织化学法检测肝脏组织中核因子κBp65（NF-κBp65）和缺氧诱导因子1α（HIF-1α）的表达变化。结果与SO组比较,IR组小肠、肝脏病理损伤加重,肝组织NF-κBp65和HIF-1α的表达显著升高,血清和肝组织中MDA、MPO水平及血清TNF-α、IL-10、ALT和AST水平升高;与IR组比较,IP组小肠、肝脏损伤减轻,肝组织NF-κBp65表达下降而HIF-1α的表达显著升高,血清和肝组织中MDA、MPO水平及血清TNF-α、ALT和AST水平均显著下降,血清IL-10水平增加,差异均有统计学意义（P＜0.05）。结论缺血后处理可以促进抗炎因子的激活,抑制NF-κB信号通路调控的炎症级联反应,上调HIF-1α的表达,减轻小肠缺血再灌注引起的肝损伤。     

缺血再灌注对大鼠岛状浅筋膜瓣超微结构的损伤及Verpamil的作用观察

探讨Ｖｅｒｐａｍｉｌ对大鼠皮瓣超微结构缺血再灌注损伤的保护作用。建立ＳＤ大鼠腹壁浅筋膜岛状皮瓣模型，缺血５小时再灌注２０分钟，在电子显微镜下观察其超微结构的变化，并用Ｖｅｒｐａｍｉｌ作保护性对比。损伤以细胞膜和线粒体为主，Ｖｅｒｐａｍｉｌ组的损伤明显减轻。实验结果提示，Ｖｅｒｐａｍｉｌ对皮瓣的超微结构具有保护作用。     

Curcumin protects against ischemia/reperfusion injury in rat kidneys

OBJECTIVES: Renal ischemia followed by reperfusion leads to acute renal failure in both native kidneys and renal allograft. We investigated the effect of curcumin on ischemia-reperfusion (I/R) injury and the antioxidant effects of curcumin in rats. METHODS: Thirty rats were randomly divided into five experimental groups (control, sham, curcumin, I/R and I/R+curcumin, n=6 each). Curcumin was administered (200 mg kg(-1)) orally to curcumin and I/R+curcumin groups for 7 days. Then, the rats were subjected to bilateral renal ischemia for 45 min and followed by reperfusion for 24 h. All rats were killed and kidney function tests, serum and tissue nitric oxide (NO), protein carbonyl (PC), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels were determined. Histopathological examinations were also performed. RESULTS: Curcumin significantly improved the urea and cystatin C levels in I/R+curcumin group compared to I/R group (p<0.05). Reduction of serum GSH-Px was significantly improved by curcumin (p<0.001), but SOD enzyme activity did not alter (p>0.05). Treatment with curcumin also resulted in significant reduction in serum and tissue MDA, NO and PC and for tissue that were increased by renal I/R injury (p<0.001 for serum and p<0.05 for tissue, respectively). In histological examination, the rats treated with curcumin had nearly normal morphology of the kidney. CONCLUSIONS: Based on our results, it can be concluded that curcumin protects the kidneys against I/R injury via its antioxidant effects.     

依达拉奉对大鼠小肠缺血-再灌注所致肺损伤的保护作用

目的探讨依达拉奉对大鼠小肠缺血-再灌注所致肺损伤的保护作用。方法雄性SD大鼠18只,随机均分为假手术组(Sham组),缺血-再灌注组(IR组)和依达拉奉组(E组)。Sham组只分离肠系膜上动脉,不做其他处理;IR组分离肠系膜上动脉,从大鼠尾静脉注射与E组等量的生理盐水后,用无创动脉夹夹闭120min后移去动脉夹,再灌注120min;E组在缺血-再灌注前静脉注射依达拉奉6mg/kg。再灌注120min后采集标本。肺组织HE染色后病理学检测,采集腹主动脉血液检测大鼠血清中TNF-α和IL-6浓度,取肺组织检测髓过氧化物酶(MPO)活性和丙二醛(MDA)浓度。结果与Sham组比较,IR组肺泡上皮细胞广泛水肿、炎性细胞浸润、肺泡肺萎陷、肺毛细血管扩张出血;E组肺组织病理改变较IR组明显改善,肺泡炎性渗出减少;E组病理评分为(2.1±0.7)分,明显低于IR组的(5.7±1.1)分,IR组病理评分明显高于Sham组的(1.5±0.2)分(P0.01);血清中TNF-α和IL-6的浓度明显少于IR组,肺组织中MPO活性和MDA浓度明显低于IR组(P0.01)。结论依达拉奉能够明显改善小肠缺血-再灌注性肺损伤。