黄芪甲甙对大鼠肾缺血再灌注损伤的保护作用

黄芪甲甙是黄芪单体之一 ,除了有抗炎 ,降压 ,改善心肌缺血等作用外 ,还具有抗脂质过氧化及清除自由基作用 ,我们观察了黄芪甲甙对大鼠肾缺血再灌注损伤的影响。一、材料与方法1.试剂与仪器 :黄芪甲甙 (纯度为83 .73 % ,上海药品检验所 ) ,实验前用生理盐水 (NS)配制成 1%、5 %和 10 % (g/L)溶液 ;超氧化物歧化酶 (SOD)试剂盒由南京建成生物研究所提供。大鼠肿瘤坏死因子 (TNF ) α酶联免疫吸附法(ELISA)试剂盒购自晶美公司。仪器 :酶标仪 (BioTEKELX80 0 ) ,分光光度计(PharmaciaBiotechUltrospect 2 0 0 0 )。2 .动物分组及方…     

葡天胶囊对大鼠肾脏缺血再灌注损伤的保护作用

目的：探讨葡天胶囊预处理对大鼠肾脏缺血再灌注损伤的保护作用。方法：雄性Wistar大鼠24只,随机分为假手术组（Sham组）、模型对照组（Control组）、葡天胶囊预处理组（PT组）,每组各8只。模型对照组及葡天胶囊160mg·kg^-1·d^-1预处理组手术建立肾脏缺血再灌注模型,缺血后1h恢复灌注,分别在恢复灌注后24h、48h、72h后检测血肌酐、尿素氮及血清白蛋白水平,并观察肾脏病理变化。结果：与假手术组相比,模型组血肌酐水平升高（P〈0.05）;葡天胶囊预处理组再灌24h、48h及72h血肌酐水平明显低于模型组（P〈0.05）;肾脏病理显示葡天胶囊预处理组肾组织病变轻于模型对照组。结论：葡天胶囊对肾脏缺血再灌注损伤有保护作用,具有一定的临床应用价值。     

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.     

FTY720预防大鼠肾脏缺血再灌注损伤的实验研究

目的:研究新型免疫抑制剂FTY720对大鼠肾脏缺血再灌注损伤(IRI)的预防作用.方法:制备大鼠肾脏IRI模型,从下腔静脉注入不同剂量的FTY720,观察术后第1、2、3、5、7 d血清肌酐值(Scr)和术后第2、7 d外周血淋巴细胞数(PLC)的变化,并在术后第2 d取肾脏作组织学检查观察急性肾小管坏死的情况.结果:FTY720处理组动物术后Scr水平显著低于对照组并呈剂量依赖性;FTY720处理组术后第2 d的PLC显著低于对照组;组织学检查显示FTY720处理组肾脏的缺血性损伤轻于对照组.结论:FTY720可以减少PLC,对大鼠肾脏IRI有预防作用.     

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。     

缺血后处理对大鼠移植肝缺血再灌注损伤的保护作用

目的探讨在体条件下缺血后处理对大鼠移植肝缺血再灌注损伤的保护作用及其可能机制。方法采用SD大鼠原位肝移植模型,供肝冷保存时间100min,无肝期控制于18min以内,60只雄性健康SD大鼠随机分为3组,对照组12只,缺血再灌注损伤组和后处理组各24只。对照组开腹后仅游离肝周韧带;缺血再灌注损伤组受体大鼠供肝切除前仅以肝素化生理盐水经门静脉灌注;后处理组供肝植入后完全再灌注前,给予多次短暂复灌复停作为缺血后处理。缺血再灌注损伤组、后处理组受体一半（6只）于再灌注后2h留取血液及肝组织,另一半（6只）于再灌注后6h留取肝组织。对照组于关腹后相应时间留取血液及肝组织。各组分别检测肝功能,采用酶联免疫吸附法测定血清肿瘤坏死因子Or．和中性粒细胞弹性蛋白酶。根据酶促反应原理,利用分光光度仪测定肝脏谷胱甘肽过氧化物酶、丙二醛、髓过氧化物酶、超氧化物歧化酶。肝组织HE染色后光镜下观察组织学变化。结果缺血再灌注损伤组和后处理组血清肝功能指标、炎性细胞因子水平及肝组织过氧化物含量均高于对照组（P〈0．05）,而后处理组较缺血再灌注损伤组则明显低（P〈0．05）;缺血再灌注损伤组和后处理组肝组织抗氧化酶活力显著低于对照组（P〈0．05）,而后处理组较缺血再灌注损伤组则明显高（P〈0．05）。结论缺血后处理对大鼠移植肝的缺血再灌注损伤有明显的保护作用。提高组织的抗氧化能力和降低炎性细胞因子水平可能是缺血后处理保护作用的机制之一。     

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.     

缺血预处理对大鼠小肠缺血再灌注损伤的作用

目的 了解缺血预处理（ＩＰ）对小肠缺血的作用。方法 在不同缺血预处理的大鼠模型上，观察缺血再灌注后肠组织腺苷酸含量和肠粘膜损伤情况。结果 ＩＰ１组（预处理：１０分钟缺血１５分钟再灌注和ＩＰ２组（３分钟缺血５分钟再灌接以７分种１０分钟再灌）小肠的ＡＴＰ和总腺苷酸含量较对照组明显增高，肠粘膜损伤亦明显减轻（Ｐ〈０．０５）。．结论 ＩＰ１和ＩＰ２组的缺血预处理对小肠缺知再灌注损伤有一定的保护作用。     

红景天苷预处理对大鼠移植肾缺血再灌注损伤的保护

目的探讨红景天苷预处理对移植肾缺血再灌注损伤的保护机制。方法建立近交系雄性SD大鼠同基因肾移植模型。共设3个组,假手术组、红景天苷预处理组、移植缺血再灌注模型组,每组24只。观察红景天苷预处理对大鼠移植肾缺血再灌注过程中血清尿素氮(BUN)、肌酐(SCr)、过氧化物歧化酶(SOD)、脂质过氧化产物丙二醛(MDA)水平变化的影响;取移植肾组织HE染色后光镜观察肾组织病理学改变;荧光探针DCFH-DA检测活性氧(ROS)含量;采用免疫组织化学染色和放射免疫法分别检测肾组织中核转录因子κB(NF-κB)阳性细胞数目和肿瘤坏死因子-α(TNF-α)、白介素1(IL-1)、白介素-6(IL-6)的表达。结果红景天苷预处理组大鼠BUN、SCr、MDA在术后轻度升高,与假手术组比较无统计学差异(P0.05),与模型组比较有统计学差异(P0.01);SOD在术后24 h增加最明显,与假手术组比较有统计学差异(P0.05),与模型组比较有统计学差异(P0.05)。ROS含量在红景天苷预处理组术后上升,与假手术组比较有统计学差异(P0.05),但不如模型组升高明显,两组比较有统计学差异(P0.01)。红景天苷预处理组肾脏病理表现损伤较轻,与模型组比较有统计学差异(P0.05)。NF-κB阳性细胞数目在红景天苷预处理组术后表达略增加,在模型组表达明显增加,两组比较有统计学差异(P0.01)。肾组织匀浆中TNF-α、IL-1和IL-6含量在假手术组和红景天苷预处理组各时间段均未见明显变化,两组间比较无统计学差异(P0.05),而模型组含量明显增加,与其他两组比较差异有显著性(P0.01)。结论红景天苷预处理通过抑制氧化应激和减轻炎性因子对大鼠肾脏移植缺血再灌注后损伤具有一定的预防和保护作用。     

丁羟茴香醚对衰老大鼠肾脏缺血再灌注损伤的保护作用

目的观察老年大鼠肾脏缺血再灌注（I／R）模型中。肾小管上皮细胞的损伤变化，探讨活性氧（ROS）清除剂对I／R损伤的保护作用。方法27月龄大鼠随机分为假手术组、I／R模型组、丁羟茴香醚（BHA）组和nicardipine组。夹闭双侧。肾动脉30min再灌注18h制成I／R模型。观察肾功能、肾脏病理改变、肾小管上皮细胞凋亡情况。检测肾组织半胱氨酸天冬氨酸蛋白酶（caspase）3、细胞色素C表达。测定肾组织脂质过氧化物丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性。结果（1）肾脏I／R损伤时，老年大鼠肾功能明显减退，肾组织病理改变比较明显，大量肾小管上皮细胞凋亡，肾组织caspase-3、细胞色素C表达明显上调。肾组织中MDA增加、SOD活性下降（P均〈0．05）。（2）BHA或nicardipine均能明显改善肾功能。肾组织病理改变和凋亡相关指标（P〈0．05）；BHA或nicardipine均能减少组织中MDA含量，部分恢复肾组织中SOD含量。结论老年大鼠肾脏I／R损伤时肾小管上皮细胞凋亡增加，肾功能减退。ROS堆积后，线粒体损伤导致肾小管上皮细胞凋亡。清除ROS可以抑制‘肾小管上皮细胞凋亡，减轻I／R损伤。     

吸入性麻醉药对肾脏缺血/再灌注损伤的影响

吸入性麻醉药对肾脏缺血/再灌注损伤的保护机制可能是通过亚中毒浓度无机氟化物的直接作用,抑制胞质膜的损伤,对丝裂原活化蛋白激酶家系(MAPKs)的影响,免疫调节和促进热休克蛋白70(HSP-70)合成实现的.而不是通过对肾血流的影响和对肾脏KATP通道的激活作用.     

Role of leukotrienes on hepatic ischemia/reperfusion injury in rats

BACKGROUND: Leukotrienes (LT), composed of cysteinyl LT (cLT; LTC(4), LTD(4), and LTE(4)) and LTB(4), are potent lipid mediators enhancing the vascular permeability and recruitment of neutrophils, which are common features of hepatic ischemia/reperfusion (I/R) injury. The aim of this study was to investigate whether LT can mediate the liver and lung injuries following hepatic I/R. MATERIALS AND METHODS: Sprague-Dawley rats were subjected to 90 min of partial hepatic ischemia followed by 3, 12, and 24 h of reperfusion. In the hepatic and pulmonary tissues, LT content and the mRNA expression of LT-synthesis enzymes, 5-lypoxygenase (5-LO), LTC(4) synthase (LTC(4)-S), and LTA(4) hydrolase (LTA(4)-H) were measured. Tissue injuries were assessed by plasma ALT, histological examination, and wet-to-dry tissue weight ratios. RESULTS: The cLT content in the hepatic tissue after 12 and 24 h reperfusion was increased 4- to 5-fold compared to controls and this was accompanied by the enhancement of hepatic edema and plasma ALT elevation. There were no significant changes in the mRNA expression of LT-synthesis enzymes in both tissues. LTB(4) levels were not increased despite a significant neutrophil infiltration in both tissues. CONCLUSIONS: These data suggest that cLT are generated in the liver during the reperfusion period and may contribute to the development of hepatic edema and exert cytotoxicity. Factors other than LTB(4) may contribute to neutrophil infiltration.     

Mannan-binding lectin mediates renal ischemia/reperfusion injury independent of complement activation

Ischemia/reperfusion injury (IRI) remains a major problem in renal transplantation. Clinical studies have identified that high serum levels of Mannan-binding lectin (MBL), the initiator of the lectin pathway of complement activation, are associated with inferior renal allograft survival. Using a rat model, we identified an entirely novel role for MBL in mediating renal IRI. Therapeutic inhibition of MBL was protective against kidney dysfunction, tubular damage, neutrophil and macrophage accumulation, and expression of proinflammatory cytokines and chemokines. Following reperfusion, exposure of tubular epithelial cells to circulation-derived MBL resulted in internalization of MBL followed by the rapid induction of tubular epithelial cell death. Interestingly, this MBL-mediated tubular injury was completely independent of complement activation since attenuation of complement activation was not protective against renal IRI. Our identification that MBL-mediated cell death precedes complement activation strongly suggests that exposure of epithelial cells to MBL immediately following reperfusion is the primary culprit of tubular injury. In addition, also human tubular epithelial cells in vitro were shown to be susceptible to the cytotoxic effect of human MBL. Taken together, these data reveal a crucial role for MBL in the early pathophysiology of renal IRI and identify MBL as a novel therapeutic target in kidney transplantation.     

丙泊酚对全脑缺血/再灌注损伤大鼠保护作用研究

目的探讨丙白酚对大鼠全脑缺血/再灌注损伤（ischemia/reperfusion injury,I/RI）的保护作用。方法65只Wistar雄性大鼠采用完全随机法分为5组：假手术组（S组）、缺血/再灌注(ischemia/reperfusion,I/R)组(I/R)组、丙泊酚组1(P1)、丙泊酚组2(P2)、丙泊酚组...     

瘦素在肝缺血/再灌注致肾损伤中作用的研究

目的：研究瘦素（Leptin）在肝缺血/再灌注（I/R）后肾组织中的表达变化,探讨其与肝I/R介导的肾损伤的关系。方法：建立大鼠70%肝I/R模型,设立假手术和缺血60min后再灌注60、150、240、360min组,观察肾脏的病理学变化,检测各组血清尿酸、总抗氧化能力,肾Leptin蛋白及其mRNA表达的变化。结果：与假手术组比较,缺血60min/再灌注150min及再灌注240min组血清尿酸显著升高,以再灌注240min升高最为显著;再灌注240min和360min组血清总抗氧化能力显著升高,以再灌注240min升高最为显著;再灌注150、240和360min组肾Leptin蛋白表达显著升高,再灌注60、240、360min组肾LeptinmRNA表达显著升高,而再灌注150min组LeptinmRNA显著降低。病理学观察提示肝I/R早期的肾损伤较重而后期显著减轻。结论：Leptin在肝I/R后肾组织内的表达变化与肾损伤密切相关,提示它可能作为一种保护因子对抗肝I/R介导的肾损伤。     

Renal ischemia/reperfusion against nephrectomy for induction of acute lung injury in rats

Purpose: Acute kidney injury (AKI) induces acute lung injury (ALI) through releasing injurious mediators or impairing clearance of systemic factors. To determine the links between AKI and ALI, pulmonary and blood variables were evaluated following induction of AKI via different experimental models of bilateral renal ischemia/reperfusion (BIR: renal ischemia with uremia), unilateral renal ischemia/reperfusion (UIR: renal ischemia without uremia), bilateral nephrectomy (BNX: uremia without renal ischemia), and unilateral nephrectomy (UNX: without uremia and renal ischemia).

Methods: Ninety male Sprague–Dawley rats were divided into six groups. Animals had 1-h bilateral or 2-h unilateral renal ischemia followed by 24-h reperfusion in the BIR and UIR groups, respectively, and 24-h period following bilateral or unilateral nephrectomy in the BNX and UNX groups, respectively. There were also sham and control groups with and without sham-operation, respectively.

Results: Plasma malondialdehyde and nitric oxide were elevated by BIR more than UIR, but not changed by UNX and BNX. UIR slightly increased plasma creatinine, whereas BIR and BNX largely increased plasma creatinine, urea, K^+?and osmolality and decreased arterial HCO₃^?, pH, and CO₂. UNX and UIR did not affect lung, but BIR and BNX induced ALI with equal capillary leak and macrophages infiltration. However, there were more prominent lung edema and vascular congestion following BNX and more severe neutrophils infiltration and P_aO₂/F_iO₂ reduction following BIR.

Conclusion: Acutely accumulated systemic mediators following renal failure in the absence of kidneys vary from those due to combined renal failure with ischemic-reperfused kidneys and consequently they induce ALI with distinct characteristics.     

纳洛酮对脑缺血/再灌注损伤保护机制的研究进展

纳洛酮是阿片受体的特异拮抗剂,近年来大量实验证实纳洛酮对脑缺血/再灌注损伤具有保护作用.其作用机制包括以下几条途径:纳洛酮能竞争性阻断内源性阿片肽对神经功能的损害作用,减少自由基的产生、减轻钙超载、逆转神经细胞内Mg2+的下降、逆转兴奋性神经毒性、抑制炎症介质的产生、改善神经元能量代谢、抑制神经元细胞凋亡.现就这一领域内的最新进展作一综述.     

Protective effect of sitagliptin against renal ischemia reperfusion injury in rats

Abstract

This study was designed to investigate the protective effects of sitagliptin on renal damage induced by renal ischemia reperfusion (I/R) in rats. For this, rats were randomly divided into four groups (n?=?8): (1) sham group, in which the rats only underwent right nephrectomy; (2) right nephrectomy and left kidney ischemia (1?h) and reperfusion (24?h) group (I/R); (3) 5?mg/kg sitagliptin administrated group, per-oral once a day for two weeks; (4) 5?mg/kg sitagliptin administrated group, per-oral once a day for two weeks before left kidney I/R (n?=?8). Sitagliptin-treated rats that underwent renal I/R demonstrated significant decrease in the serum urea nitrogen and creatinine and also, lipid peroxidation, total oxidant status and malondialdehyde level in the renal tissue when compared to the renal I/R group. Additionally, reduced glutathione, glutathione peroxidase, superoxide dismutase, catalase and total antioxidative capacity were significantly increased after renal I/R in sitagliptin-treated rats. Our histopathological findings were in accordance with these biochemical results. In sum, in the current study all of our results indicated that sitagliptin treatment ameliorated renal damage induced by renal I/R in rats.     

Melatonin ameliorates renal ischemia/reperfusion injury

BACKGROUND: We studied whether melatonin is able to reduce organ damage during renal ischemia/reperfusion via its effects on the oxidative response in early and late reperfusion. MATERIALS AND METHODS: Renal ischemia/reperfusion injury (I/R) was induced in two groups of rats by 75 min occlusion of the left renal artery and vein and right nephrectomy, followed by reperfusion. The formation of reactive oxygen species was evaluated in the early reperfusion phase (60 min) by lipid peroxidation products and glutathione assay. In the late reperfusion phase (24 h) tissue neutrophil infiltration, inducible nitric oxide synthase (iNOS) gene expression, and histopathology were evaluated. Groups received either systemic melatonin (MEL) or normal saline (NS). There were two nonischemic sham control groups, one with and another without melatonin (S+MEL and S). RESULTS: Creatinine was higher in the NS group at all times. A reduction in glutathione and increases in lipid peroxidation products and myeloperoxidase activity induced by I/R indicated renal injury involving reactive oxygen formation. Melatonin reversed this oxidant response and reduced the rise in creatinine and iNOS expression. Seven-day group survivals were 5/10 for NS, 8/10 for MEL, and 10/10 for both Sham groups. CONCLUSIONS: Exogenous melatonin is able to preserve renal functional status following I/R-induced injury by increasing glutathione and reducing lipid peroxidation in the early reperfusion phase, without any apparent effect on neutrophil infiltration in the late reperfusion phase.     

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.