血小板激活因子拮抗剂E5880在肝切除时对肝脏缺血再灌注损伤的保护作用

目的探讨血小板激活因子（platelet—activating factor，PAF）拮抗剂E5880在肝脏血流完全阻断下行70％肝切除术中的肝脏保护作用。方法实验用家兔16只，分成2组。A组：术前无任何预处理，在Pringle法阻断肝脏血流20min下行70％肝切除；B组：术前用E5880（0．3mg／kg）行预处理，在Pringle法阻断肝脏血流20min下行70％肝切除。肝脏再灌注后评估两组动物肝脏功能。结果B组7d存活率较A组显著提高（38％vs0，P〈0．05）；肝脏再灌注1h和4h时，B组血清AST、ALT、mAST、LDH的升高明显被抑制；B组门静脉压和肝脏能荷较A组有明显改善；A、B组肝动脉和门静脉血液中内皮素-1水平均明显升高。B组的肝脏白细胞浸润明显减少。结论术前使用E5880预处理，可以保护在Pringle法阻断肝脏血流20min下行70％肝切除术后肝脏功能。     

依达拉奉对大鼠肝I/R损伤的保护作用

目的探讨依达拉奉对大鼠肝缺血再灌注(I/R)损伤中的保护作用。方法将60只大鼠随机分为实验组和对照组,建立常温下部分肝脏I/R动物模型。在肝脏I/R开始时和1 h后对实验组大鼠给予依达拉奉注射液,对照组给予同等容量的生理盐水。再灌注0,2,4 h测定肝脏脂质过氧化反应物(LPO)浓度和肝脏酶学指标及TNF-α和E-selectin的mRNA,并行两组肝脏的病理学检查。结果再灌注2,4 h实验组大鼠肝脏LPO反应程度和肝脏酶指标检测值明显低于对照组(P0.05)。再灌注2 h肝TNF-αmRNA和E-selectinmRNA表达明显低于对照组(P0.05)。再灌注2 h实验组大鼠肝脏切片的E-selectin免疫反应性明显低于对照组。结论依达拉奉能抑制氧化应激反应,从而降低肝I/R损伤;并显著减少炎性细胞和黏附分子的产生,抑制炎性反应的发生。     

己酮可可碱对肝脏缺血再灌注损伤保护作用的实验研究

目的　观察大鼠肝脏缺血再灌注后肿瘤坏死因子 -α (TNF α)早期释放及核因子κB(NFκB )活化对炎性介质表达和中性粒细胞浸润的影响。探讨其对肝缺血再灌注损伤的意义。方法　建立大鼠肝脏部分热缺血模型 ,己酮可可硷 (PTX )组于缺血前 1h腹腔注射PTX 5 0mg/kg ,对照组同法等量生理盐水注射 ,另设假手术组。结果　对照组相比 ,PTX组TNF α浓度、NFκBp65含量 (IOD )、巨噬细胞炎性蛋白 -2 (MIP 2 )和细胞间黏附因子 -1(ICAM 1)mRNA表达量 (IOD )、髓过氧化物酶(MPO )活性 (U/g)均明显降低 (均P <0 .0 5 )。再灌注 6hPTX组天门冬氨酸转氨酶 (AST)、丙氨酸转氨酶 (ALT)、乳酸脱氢酶 (LDH )含量 (U/L)和湿重 /干重 (W /D )水平也显著降低 (均P <0 .0 5 )。结论　PTX通过减少TNF α的早期释放 ,抑制NFκB活化 ,从而下调趋化因子、黏附分子表达和减少中性粒细胞浸润 ,从而得以减轻肝脏缺血再灌注损伤。     

Protective effect of erythropoietin on renal ischemia and reperfusion injury

BACKGROUND: Multiple protective effects of erythropoietin (EPO), such as antiapoptotic, antioxidant, angiogenic and neuroprotective effects, against ischemia have been demonstrated in cell culture and animal models. Genistein is also a potent tyrosine kinase inhibitor. The aims of the present study were to evaluate the effects of EPO on renal ischemia/reperfusion injury and to determine the role of the tyrosine kinase pathway on this process. METHODS: Sprague-Dawley rats were assigned to five groups: (i) sham (Group I); (ii) control with renal ischemia (right nephrectomy and clamping on the left renal pedicle for 45 min and reperfusion; Group II); (iii) EPO + ischemia (Group III); (iv) genistein (an inhibitor of tyrosine kinase) + ischemia (Group IV); and (v) EPO + genistein + ischemia (Group V). Recombinant human EPO (1000 IU/kg) and genistein (10 mg/kg) were given 2 hours before ischemia. Blood samples and the left kidney were obtained after 45 min of reperfusion from half of the rats and after 24 h from the other half. RESULTS: The blood urea nitrogen, creatinine, tumour necrosis factor-alpha (P < 0.05) and interleukin-2 (P < 0.01) levels, and renal tissue lipid peroxidation (P < 0.05) were significantly lower in Group III than in Group II at 45 min of reperfusion. Following 24 h of reperfusion, EPO decreased tissue peroxidation and histopathological injury, whereas genistein reversed it. The most prominent ischemic injury was observed in Group IV in which genistein was administered. There was no significant difference between Groups II and V. CONCLUSIONS: These results suggest that EPO is effective in attenuating renal ischemia/reperfusion injury, and this effect may be related to tyrosine kinase activity.     

Gpx1-Klk1转基因对肾缺血再灌注损伤保护作用的研究

目的 制备人谷胱甘肽过氧化物酶（Gpx1）、 组织激肽释放酶（Klk1）共转基因小鼠,在此基础上制作肾缺血再灌注损伤小鼠模型。观察转基因小鼠对缺血再灌注损伤的耐受能力。在体研究Gpx1-Klk1转基因对肾缺血再灌注的保护作用。 方法 应用基因工程技术制备pKsp-Gpx1-IRES-Klk1质粒,酶切后回收转基因片段并纯化,通过外源基因受精卵雄原核显微注射法制备Gpx1-Klk1共转基因小鼠。采用丝线悬吊控制法制备转基因小鼠肾缺血再灌注模型。设立C57BL野生型小鼠同法制备的肾缺血再灌注损伤为对照。在肾缺血再灌注实验前后,测定血尿素氮、血肌酐、肾组织中超氧化物歧化酶（SOD）、丙二醛（MDA）、总一氧化氮合酶（tNOS）及诱导型一氧化氮合酶（iNOS）。留取肾脏组织制备病理切片,观察Gpx1-Klk1转基因小鼠抗肾缺血再灌注损伤的能力。 结果 获得全长为6.585 kb的pKsp-Gpx1-IRES-Klk1重组质粒,并证明了该克隆的正确性。在转基因小鼠制备过程中,共获得525枚注射卵,移植成功率为81.0%,小鼠出生总数109只。经基因组DNA的PCR检测,确认10只为转基因阳性小鼠,阳性率为9.2%。Western印迹法检测证实了阳性转基因小鼠肾脏组织有Gpx1和Klk1蛋白强表达。转基因小鼠（实验组）和野生型小鼠（对照组）肾缺血再灌注损伤模型建立后,实验组血样中尿素氮及肌酐水平显著低于对照组（P < 0.01）;肾脏组织中SOD显著高于对照组 （P < 0.01）,MDA显著低于对照组（P < 0.01）;两组肾组织中tNOS较缺血再灌注前均显著升高,且实验组显著高于对照组（P = 0.025）,实验组肾组织中iNOS显著低于对照组（P < 0.01）。缺血再灌注后,实验组肾组织间质轻度水肿,肾小管上皮坏死细胞较少,对标本损伤程度采用半定量评分后显示,实验组损伤程度显著轻于对照组（1.58±1.05比3.95±0.80,P < 0.05）。 结论成功制备Gpx1-Klk1转基因小鼠。Gpx1-Klk1过表达对肾缺血再灌注损伤的保护作用。     

右美托咪定对脏器缺血/再灌注损伤的保护作用机制

背景 右美托咪定(dexmedetomidine,Dex)是一种新型高选择性α2-肾上腺素受体(alpha-2-adrenergic receptor,α2-AR)激动剂,Dex除具有镇静、镇痛、围术期交感阻滞的作用外,大量的研究表明Dex对多脏器的缺血/再灌注损伤(ischemidreperfusion injury,I/RI)具有保护作用. 目的 综述国内外Dex对多脏器I/RI保护机制的研究进展,为Dex脏器保护机制的研究提供思路. 内容 Dex通过减轻再灌注过程中的氧化应激反应,降低炎性因子的表达,减少机体细胞凋亡,保护红细胞变形能力来发挥脏器保护作用. 趋势 随着Dex对多脏器I/RI的保护机制不断被阐明,将为其临床应用提供更为深入的理论基础.     

STF-083010对肾脏缺血-再灌注损伤的保护作用

目的 观察STF083010对急性肾缺血-再灌注损伤的作用,探讨其损伤保护作用的机制.方法 选择健康雄性SD大鼠30只,随机分为假手术组(打开腹腔)、I-R组(建立大鼠肾I-R损伤模型)与STF083010组.分别在缺血-再灌注24h后处死大鼠,取血液和肾组织.全自动生化仪检测各组血清尿素氮(BUN)及肌酐(Scr)水平.PAS染色观察大鼠肾组织病理变化,免疫组化检测肾脏组织中XBP1、GRP78蛋白的表达.Quantitative real-time PCR(QPCR)测定大鼠肾组织标本中XBP1、GRP78 mRNA水平.结果 I-R组肌酐、尿素氮水平与假手术组相比差异均有统计学意义(P＜0.05).STF-083010组与I-R组相比,差异亦有统计学意义(P＜0.05).PAS病理图片可见STF-083010组肾小管损伤较I-R组明显减轻(P＜0.05);免疫组化检测显示STF-083010组XBP1的表达较I-R组明显降低(P＜0.05),STF-083010组GRP78蛋白的表达较I/R组明显升高;QPCR结果显示STF-083010组XBP1 mRNA水平较I-R组明显降低(P＜0.05),STF-083010组GRP78 mRNA较I-R组明显升高(P＜0.05).结论 STF-083010可以对大鼠肾脏缺血-再灌注损伤性保护作用.     

缺血预处理对肝硬化大鼠肝缺血再灌注损伤的保护作用

目的探讨缺血预处理(IP)对硬化肝脏缺血再灌注(I/R)损伤的保护作用.方法将采用四氯化碳复制的SD肝硬化大鼠随机按I/R前是否行IP分为预处理(IP组)和非预处理组(NIP组).比较两组大鼠肝I/R后肝功能、肝组织的抗氧化能力、能量代谢、NO含量与组织学变化及大鼠术后1周的存活率.结果与NIP组大鼠比较,IP组血清谷丙转氨酶,谷草转氨酶及乳酸脱氢酶活性显著降低(分别为P＜0.05,P＜0.001和P＜0.001);肝组织的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)活力明显提高(分别为P＜0.05和P＜0.01);脂质过氧化产物丙二醛(MDA)含量降低(P＜0.05);ATP含量与能荷值(EC)增高(分别为P＜0.01和P＜0.05);NO合成显著增加(P＜0.01);光镜和电镜检查显示肝损伤的组织形态学表现明显减轻.大鼠术后1周存活率虽有提高,但两组差别无统计学意义(P=0.069).结论 IP对肝硬化大鼠的肝I/R损伤具有明显的保护作用.     

Protective effect of Antrodia Camphorata on bladder ischemia/reperfusion injury

Introduction  

Obstructive bladder dysfunction is directly related to ischemia/reperfusion injury characterized by damage to nerves, synapses and smooth muscle cells within the bladder wall. Antrodia Camphorata (AC) has significant antioxidant, antiinflammatory and cell-cycle inhibition properties. The specific aim of this study was to evaluate whether orally administered AC can protect rabbit bladders from the progressive dysfunctions induced by bilateral ischemia/reperfusion (I/R).     

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。     

intermedin对大鼠肾脏缺血再灌注损伤的保护作用及其机制

目的 观察intermedin（IMD）对大鼠肾脏缺血再灌注损伤（IRI）的保护作用并探讨其机制。 方法 健康雄性Wistar大鼠24只随机分为对照组、IRI组、转空质粒组、转IMD质粒组。动物右肾切除后,用超声微泡技术将质粒转染入肾脏,1周后制作肾脏IRI模型。PAS染色观察肾脏病理损伤,比色法检测肾组织超氧化物岐化酶（SOD）、髓过氧化物酶（MPO）和天冬氨酸半胱氨酸蛋白酶3（caspase-3）,以及脂质过氧化物丙二醛（MDA）含量。免疫组织化学方法检测细胞间黏附分子1（ICAM-1）、P选择素及内皮素1（ET-1）表达。TUNEL染色检测肾组织细胞凋亡。 结果 PAS染色结果显示,IRI组肾小管及间质病理损伤显著重于对照组（P < 0.01）;转IMD组肾组织病理损伤则显著轻于IRI组（P < 0.01）。IRI组肾组织SOD活性显著低于对照组（P < 0.05）,MPO活性、活性caspase-3、MDA含量及ICAM-1、P选择素和 ET-1表达均显著高于对照组（均P < 0.01）;转IMD组SOD活性显著高于IRI组（P < 0.05）,MPO活性、活性caspase-3、MDA含量及ICAM-1、P选择素和ET-1表达均显著低于IRI组（均P < 0.01）。TUNEL染色显示,IRI组肾组织凋亡细胞数显著高于对照组（34.83%±8.75%比3.33%±0.47%,P < 0.01）;转IMD组肾组织凋亡细胞数（20.67%±7.71%）则较IRI组显著减轻（P < 0.01）。转空质粒组和IRI组以上指标差异均无统计学意义。 结论 IMD能减轻肾脏IRI,其机制至少部分与抑制氧自由基生成、炎细胞浸润及炎性因子ICAM-1、P选择素生成、ET-1生成、细胞凋亡有关,从而减轻肾组织局部氧化应激反应产生的活性氧。     

Protective effects of D-allose against ischemia reperfusion injury of the rat liver

Background/Purpose. d-Allose, a rare sugar, has been reported to inhibit segmented neutrophil production without causing any significant detrimental clinical effects. Our previous study demonstrated the immunosuppressive effect of d-allose in a rat model of liver transplantation. Neutrophils are closely involved in the process of hepatic ischemia/reperfusion (I/R) injury. One possible mechanism is the adherence of neutrophils to the hepatic sinusoidal endithelium following microcirculatory failure. Methods. The present study investigated the effects of d-allose on the involvement of neutrophils, with particular emphasis to the microcirculation in a model of hepatic I/R. Ischemia was induced by occluding the hepatoduodenal ligament for 90min. d-Allose was infused 2h before ischemia. Normal saline was infused in the control group. Liver tissue blood flow (LTBF) and portal venous flow (PVF) were measured before and after ischemia. Myeloperoxidase (MPO) and ATP were measured at, before inducing ischemia, at the end of ischemia, and at the end of 2-h reperfusion. Liver enzyme analysis and histology were done at the end of reperfusion. Postreperfusion animal survival was followed for 15 days. Results. d-Allose significantly improved the liver hemodynamics and postreperfusion animal survival, with a significant decrease in liver tissue MPO, liver enzymes, and the number of neutrophils. ATP level was improved significantly in the d-allose group. Histology revealed significant sinusoidal congestion and tissue necrosis after 2-h reperfusion in the control group. Conclusions. d-Allose exerted its protective effects against liver damage incurred when the liver was injured by warm ischemia and reperfusion mainly by the suppression of activated neutrophils.     

Protective role of nitric oxide in ischemia and reperfusion injury of the liver

Background: The suppressed production of nitric oxide (NO), associated with endothelial dysfunction, is thought to be a cause of ischemia and reperfusion injury of the liver. But findings of the salutary effects of NO enhancement on such injury have been conflicting. In this study, we tested our hypothesis that NO enhancement would attenuate ischemic liver injury. For this purpose, an NO precursor, L-arginine, and a novel NO donor, FK409, were applied to a 2-hour total hepatic vascular exclusion model in dogs.Study Design: L-arginine was administered IV at a dose of 100 mg/kg twice (n = 5), while 300 mg/kg twice of FK409 was infused continuously into the portal vein (n = 5). The drugs were given to the animals for 30 and 60 minutes before and after ischemia, respectively. Nontreated animals were used as the control (n = 10). Two-week survival, systemic and hepatic hemodynamics indices, liver function tests, energy metabolism, and histopathology were analyzed.Results: Both treatments comparably augmented hepatic tissue blood flow, decreased liver enzyme release, and increased high-energy phosphate restoration during the reperfusion period, all of which contributed to rescuing all of the treated animals from the 2-hour total hepatic ischemia. In contrast, ischemia caused 70% mortality in the control group. Histologically, structural abnormality and neutrophil infiltration were markedly attenuated by the treatments. Systemic hypotension was observed in the animals treated with FK409, however.Conclusions: Our data demonstrate that NO enhancement alleviates the liver injury caused by ischemia and reperfusion. The supplementation of L-arginine, rather than FK409, is considered more applicable to clinical use because of the absence of systemic adverse effects.     

Protective effect of tadalafil on ischemia/reperfusion injury of rat ovary

Background/Purpose

The aim of the study was to evaluate the effects of tadalafil (TDF) on ischemia/reperfusion (I/R) injury in rat ovaries.

Methods

Thirty-five female Sprague-Dawley rats were randomly divided into 5 groups (n = 7): sham (S), I/R1, I/R2, TDF1, and TDF2. In the I/R1 and TDF1 groups, 3-hour ischemia was followed by 12-hour reperfusion; and in the I/R2 and TDF2 groups, 3-hour ischemia was followed by 24-hour reperfusion. In the TDF groups, 30 minutes before reperfusion, a single dose of 5 mg/kg TDF was administered intraperitoneally. The ovarian tissue levels of malondialdehyde and nitric oxide (NO), and the activities of superoxide dismutase and catalase were measured biochemically. Tissue damage to ovarian tissue was scored by histopathologic examination.

Results

The tissue malondialdehyde levels were significantly higher and the catalase and superoxide dismutase activities were significantly lower in the I/R groups compared with the S and TDF groups (P < .05). The NO levels were significantly higher in the TDF1 group than the S and I/R1 groups (P < .05). Although the NO levels were increased in the TDF2 group compared with the I/R2 group, the difference was not significant. Ovarian tissue damage scores of the I/R groups were significantly higher than those of the S group (P < .05). Treatment with TDF significantly decreased the ovarian tissue damage scores in the TDF groups compared with the I/R groups (P < .05).

Conclusions

Tadalafil is effective in preventing tissue damage induced by I/R in rat ovaries.     

Protective effect of N-acetylcysteine on renal ischemia/reperfusion injury in the rat

BACKGROUND: Oxygen free radicals are important components involved in the pathophysiological tissue alterations observed during ischemia/reperfusion (I/R). METHODS: The protective effect of N-acetylcysteine (NAC) against the damage inflicted by reactive oxygen species during renal I/R was investigated in Wistar Albino rats using biochemical parameters. Animals were unilaterally nephrectomized, and subjected to 45 min of renal pedicle occlusion followed by lh of reperfusion. N-acetylcysteine (150 mg/kg, i.p.) or vehicle was administered twice, 15 min prior to ischemia and immediately before the reperfusion period. At the end of the reperfusion period, rats were killed by decapitation. For biochemical analysis, the lipid peroxidation product malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and protein oxidation (PO) were tested. Serum creatinine and BUN concentrations were measured for the evaluation of renal function. RESULTS: I/R induced nephrotoxicity, as evidenced by increases in BUN and creatinine, was reversed by NAC. The decrease in GSH and increases in MDA, MPO and PO induced by I/R indicated that renal injury involves free radical formation. CONCLUSIONS: Since NAC reversed these oxidant responses, and protected rat renal proximal tubules from in vitro simulated reperfusion injury, it seems that NAC protects kidney tissue against oxidative damage.     

吡咯烷二巯基氨甲酸对大鼠肾缺血再灌注的保护作用及机制

目的 探讨吡咯烷二巯基氨甲酸(PDTC)对大鼠肾缺血再灌注的保护作用及可能的机制.方法 选择成年、健康及雄性的Wistar大鼠56只,随机分为缺血再灌注损伤(IRI)组,PDTC组及对照组.IRI组:24只,建立大鼠肾缺血再灌注模型;PDTC组:24只,缺血再灌注前15 min经鼠尾静脉注射PDTC 150 mg/kg,其余步骤同IRI组;对照组:8只,不给予缺血再灌注处理.IRI组和PDTC组分别于再灌注后2、6和24 h检测大鼠血清肌酐(Cr)和尿素氮(BUN)水平;检测肾组织中自细胞介素8(IL-8)和肿瘤坏死因子α(TNF-α)的含量;逆转录聚合酶链反应(RT-PCR)检测肾组织中核因子-κB(NF-κB)和诱导型一氧化氮合酶(iNOS)mRNA表达水平;苏木素-伊红(HE)染色观察大鼠肾组织的病理变化.取对照组的各项数据作为正常对照.结果 IRI组大鼠再灌注后各时间点的血Cr、BUN、IL-8及TNF-α含量、NF-κB和iNOS mRNA表达水平均高于对照组和PDTC组(P<0.05).再灌注后6 h时,PDTC组大鼠肾组织中IL-8和TNF-α含量与对照组比较,差异无统计学意义(P>0.05).再灌注后24 h时,PDTC组大鼠各项生化指标与对照组相比,差异均无统计学意义(P>0.05).PDTC组大鼠肾损伤的病理变化较IRI大鼠明显减轻.结论 PDTC通过抑制NF-κB,有效减少IL-8,TNFα和iNOS的产生,对肾缺血再灌注有良好的保护作用.     

乌司他丁对大鼠肾缺血/再灌注损伤的保护作用

目的探讨乌司他丁对大鼠肾缺血/再灌注(I/R)损伤的作用及其机制.方法雄性SD大鼠75只,随机分为三组假手术对照组(C组)、肾I/R组(I组)、乌司他丁组(U组),每组25只.I组和U组大鼠夹闭双侧肾蒂45min后重新开放肾脏血供,制作肾脏I/R模型,C组不夹闭双侧肾蒂.U组缺血前30min及再灌注开始时静脉注射乌司他丁1.25万单位,I组分别静脉注射生理盐水1ml.各组在再灌注后0、2、6、12、24h时取标本,测定血尿素氮(BUN)和血肌酐(Cr)浓度,并制备肾脏病理切片,采用免疫组化方法测定热休克蛋白70(HSP70)和bcl-2蛋白的表达.结果与I组比较,C组在再灌注后各时点血清BUN和Cr浓度均降低(P＜0.05),U组在再灌注后12、24h时血清BUN和Cr浓度也降低(P＜0.05).C组肾脏未发现明显的形态学改变;I组近曲小管上皮细胞空泡变性和坏死,肾小管腔扩张,内可见管型和坏死脱落细胞,可见管周血管明显扩张淤血;U组近曲小管上皮细胞肿胀、颗粒变性,罕见管型,管周稍有淤血.与I组比较,C组在再灌注后0、6、12、24h时Paller评分降低(P＜0.05),U组在再灌注后0、6、24h时Paller评分也降低(P＜0.05),C组再灌注后12、24h时HSP70表达降低(P＜0.05),U组在再灌注后6、24h时bcl-2蛋白表达增强(P＜0.05).结论乌司他丁对肾脏I/R损伤有保护作用,其机理可能与上调肾脏bcl-2蛋白表达有关.     

黄芪对兔周围神经再灌注损伤的保护作用

目的　探讨黄芪注射液对家兔周围神经缺血再灌注损伤的影响。方法　 40只家兔建立周围神经再灌注模型 ,随机分成 5组 :对照组、缺血组、再灌注组、黄芪治疗Ⅰ组、黄芪治疗Ⅱ组 ,动态观察坐骨神经相应各项指标变化。结果　随制成血再灌注时间延长 ,缺血组、再灌注组运动神经传导速度分别减慢为 ( 4 .10 2± 0 .992 )m/s、( 5 .898± 8.891)m /s ,动作电位波幅分别降低为( 4 .2 71± 1.0 71)mV、( 2 .2 5 2± 1.5 2 7)mV ,潜伏期延长为 ( 1.92 1± 0 .2 0 4)ms、( 2 .3 93± 0 .2 3 1)ms ;组织超氧化物歧化酶 (SOD)活性降低分别为 ( 18.93± 9.88) μU/L、( 2 8.13± 9.72 ) μU /L、脂质过氧化产物丙二醛 (MDA)含量增加 ( 1.2 9± 0 .2 1) μmol/L、( 4 .2 9± 0 .14 ) μmol/L(P <0 .0 5 ) ,病理改变加重。黄芪Ⅰ组相对缺血组、黄芪Ⅱ组相对再灌注组神经传导速度增快 ( 3 .182± 0 .83 9)ms、( 3 .2 71± 1.0 13 )ms ,动作电位波幅增高 ( 1.867± 0 .5 12 )mV、( 2 .467± 0 .2 19)mV ,潜伏期缩短( 1.3 17± 0 .3 2 4)ms、( 2 .3 87± 0 .175 )ms ;组织SOD活性增加 ( 10 .64± 0 .79) μU/L、( 13 .94± 0 .83 )μU/L ,脂质过氧化产物MDA含量降低 ( 1.69± 0 .0 1)mol/L、( 1.0 6± 0 .2 0 )mol/L ( P <     

Intermedin预处理对大鼠肾缺血离体再灌注损伤的保护作用

目的:探讨IMD预处理对大鼠肾缺血再灌注(ischemia/reperfusion,I/R) 伤的保护作用.方法:用动脉夹夹闭大鼠左侧肾蒂1 h再灌注1 h的手术方法制成急性肾缺血再灌注损伤动物模型,将动物分为对照组、肾I/R组、IMD高、低剂量预防组、ADM预防组,检测离体肾脏流出液量及其中乳酸脱氢酶(LDH)含量、肾脏组织过氧化氢酶(CAT)、总超氧化物歧化酶(T-SOD)活性和丙二醛(MDA)含量,肾组织光镜下形态学观察.结果:与单纯肾I/R组相比,IMD高、低剂量组和ADM组均显著增加了离体肾脏流出液量(P<0.01),均显著降低了乳酸脱氢酶活性(P<0.01),均显著增加了离体肾脏的T-SOD和CAT活性(P<0.001);且IMD低剂量组的作用更加显著(P<0.05),均明显抑制了MDA的生成(P%0.001),形态学显示肾I/R组肾小球结构异常,细胞坏死、混浊肿胀或凋亡,基底膜剥脱,IMD高、低剂量组和ADM组肾小球结构基本正常,仅有中、重度空泡形成(P<0.01).结论:IMD、ADM预处理对肾I/R损伤有保护作用,其机制可能与清除自由基、减轻脂质过氧化有关.     

Protective effect of quercetin on renal ischemia/reperfusion injury in rats

BACKGROUND: There is increasing evidence to suggest that toxic oxygen radicals play a role in the pathogenesis of ischemia/reperfusion (I/R) injury in the kidney. The aim of this study was to evaluate whether quercetin, an oxygen free radical scavenger, protects kidney tissue. METHODS: A renal I/R injury was induced by a left renal pedicle occlusion by ischemia for 45 min, followed by 60 mins of reperfusion with contralateral nephrectomy in rats. The rats were pretreated intraperitoneally with a quercetin suspension (50 mg/kg) 60 min before the ischemia induction. Thiobarbituric acid reactive substances (TBARS), protein carbonyl content, tumor necrosis factor alpha (TNF-alpha), reduced glutathione (GSH) levels, myeloperoxidase (MPO) catalase (CAT) and superoxide dismutase (SOD) activities were determined in renal tissue. RESULTS: There were 3 groups of rats, the control group, the I/R group and the I/R+Q group. Our results indicate that TBARS, TNF-alpha levels, MPO activity and protein carbonyl content were significantly higher in the I/R group than those in the control group (p<0.05, p<0.01, p<0.01 and p<0.01, respectively). Quercetin administration significantly decreased these parameters (p<0.05, p<0.01, p<0.05 and p<0.01, respectively). GSH levels, SOD, and CAT activities significantly decreased after I/R injury when compared to the control group (p<0.01, p<0.05 and p<0.01, respectively). Quercetin treatment significantly increased GSH levels and activities of these enzymes when compared to the I/R group (p<0.05, p<0.01, p<0.05, respectively). CONCLUSIONS: These results suggest that quercetin reduces renal oxidative injury and facilitates repair. Quercetin can have a role in a renoprotective therapeutic regimen.