活体在线法检测肾缺血再灌注过程中抗坏血酸变化研究

目的研究缺血再灌注情况下兔肾内抗坏血酸的变化规律。方法实验组及假手术组各8只新西兰兔。实验组动物麻醉后，在肾缺血再灌注过程中利用微透析及电化学分析系统持续检测抗坏血酸的水平。假手术组实验方法同实验组，但不阻断动脉。结果实验组缺血期和再灌注期微透析液内抗坏血酸最高浓度均比缺血前期平均浓度升高，分别升高57．7％、115．9％；再灌注期抗坏血酸的最高浓度比缺血期最高浓度升高37．0％。以上差异均有显著性（P〈0．05）。实验组与假手术组各时间段抗坏血酸浓度差异有显著性（P〈0．05）。假手术组微透析液内抗坏血酸水平保持相对稳定。结论微透析技术与活体在线电化学检测技术相结合的方法是检测肾抗坏血酸变化的一种很好的手段，抗坏血酸是肾缺血再灌注损伤的一个灵敏指标。抗坏血酸在肾缺血再灌注情况下的变化是多种因素共同作用的结果。     

微透析技术实时检测肾热缺血后葡萄糖变化的动物实验研究

目的探讨应用微透析技术研究兔肾热缺血再灌注损伤后肾皮质葡萄糖浓度变化规律的可行性。方法新西兰大耳白兔20只,其中实验组10只,麻醉后游离出右肾及其动静脉,将微透析探针置入肾背侧皮质内,复方氯化钠溶液持续灌注平衡60min后,连接电化学分析系统,阻断肾动静脉60min,然后开放动静脉,观察60min。利用电化学方法实时在线检测肾透析液中葡萄糖含量的变化。对照组10只,仅游离出肾动静脉而不结扎,同样留置微透析针取样,连续检测葡萄糖浓度,比较2组在正常灌注期、缺血期和再灌注期葡萄糖浓度的变化。结果葡萄糖电极的电流响应与其浓度呈良好的线性关系,微透析针的回收率在（63.6±2.1）%。实验组兔肾皮质正常状态下测得的透析液葡萄糖浓度为（1.89±0.37）mmol/L,缺血期葡萄糖浓度为（0.69±0.12）mmol/L（LSD检验,P=0.000）,缺血期较自身正常灌注期降低（36.7±2.4）%;再灌注期葡萄糖浓度为（0.62±0.14）mmol/L（LSD检验,P=0.000）。与对照组比较,实验组缺血期（t=-11.975,P=0.000）和再灌注期（t=-11.993,P=0.000）葡萄糖浓度显著降低。结论应用微透析与活体在线电化学技术相结合的方法可以方便、灵敏检测肾缺血再灌注损伤后葡萄糖水平,可以较好地实时反映肾皮质缺血状态。     

微透析-电化学法检测缺血再灌注损伤对兔肾皮质乳酸代谢的影响

目的：采用微透析-电化学方法研究缺血再灌注损伤状况下兔肾皮质乳酸浓度变化的规律。方法：普通级大耳白兔16只，其中实验组10只，戊巴比妥麻醉后，游离出左肾，将微透析探针置入肾皮质内，正常血流灌注状态下平衡60min，再用动脉夹阻断肾动静脉60min，然后开放动静脉60min。应用电化学方法实时在线监测肾透析液中乳酸含量的变化。假手术组6只，同样留置微透析针取样，连续测定乳酸浓度各60min，但是对照组仅游离肾动静脉而不结扎血管。比较正常灌注期、缺血期和再灌注期三种状态下乳酸浓度的变化。结果：兔肾皮质正常状态下透析液乳酸浓度为（1．35±0．33）mmol，缺血期乳酸平均浓度为（3．33±0．35）mmol，缺血期较自身正常灌注期平均升高241．8％。再灌注期肾皮质透析液乳酸浓度平均为（1.86±0．46）mmol，再灌注期内比正常灌注期乳酸浓度平均升高131．4％。实验组内正常灌注期与缺血期。肾皮质乳酸浓度差异有统计学意义（P〈0．001），与再灌注期乳酸浓度比较差异无统计学意义（P〉0．05）。两组正常灌注期和再灌注期组间差异无统计学意义（P〉0．05）；缺血期乳酸浓度组间差异有统计学意义（P〈0．05）。结论：应用微透析-电化学法测定乳酸水平可以良好地实时反映肾皮质缺血状态；热缺血60min内，再灌注后肾皮质乳酸浓度可以下降接近正常水平。     

抗氧化剂防治肾缺血再灌流损伤的研究

抗氧化剂防治肾缺血再灌流损伤的研究吴雄飞，李为兵，帅学焱，金锡御氧自由基在组织缺血再灌流损伤中起重要作用，已由实验证实并日益引起重视。我们在家兔肾动脉钳夹致肾缺血再灌流模型上，采用腹主动脉灌注直接给药的方法，观察抗氧化剂超氧化物歧化酶（ＳＯＤ）；过氧...     

猪活体肾移植模型中腹腔镜手术对移植肾缺血再灌注损伤的影响

目的观察猪活体肾移植手术中腹腔镜手术对移植肾缺血再灌注损伤的影响。方法用猪同种肾移植模型（白色小型猪CEMP-III黑色小型猪CEMP-I），分腹腔镜组和开放手术组活体取肾。移植后1、3d观察移植肾组织学分析了解缺血再灌注损伤的程度，实时荧光定量聚合酶链反应（PCR）检测TLR4（Toll-like receptor）mRNA的表达了解导致缺血再灌注损伤差异的机制。结果组织学分析发现移植后1d两组移植肾以肾小管浊肿为主，移植后3d腹腔镜组移植肾肾小管多见片状坏死，而开放手术组仅见肾小管浊肿和局灶性坏死；检测移植肾中11LR4mRNA表达，发现移植后第1天两组11LR4mRNA表达指数差异无统计学意义（11．934-3．66比12．464-2．60，P〉0．05），移植后第3天两组TLR4mRNA表达指数差异有统计学意义（30．164-6．19比61．534-9．47，P〈0．01）。结论腹腔镜活体取肾手术中C02气腹引起腹内压增加影响供肾血流，导致早期移植肾有加重缺血再灌注损伤的风险，11LR4表达增加可能发挥重要作用。     

内皮素在急性肾缺血再灌注损伤中作用的实验研究

内皮素在急性肾缺血再灌注损伤中作用的实验研究涂响安余明年谢佛龙赵志毅冯家骅何炳辉彭轼平用放射免疫方法（ＲＩＡ）检测大鼠左肾动脉夹闭６０分钟致急性肾缺血再灌注损伤（ＡＲＲＩ）模型其血浆和肾组织内皮素（ＥＴ）水平变化，以探讨ＥＴ在急性肾缺血再灌注损伤中的...     

大鼠肾下腹主动脉阻断后再灌注自由基变化对肾功能影响实验研究

目的 探讨大鼠肾下腹主动脉阻断后再灌注自由基变化对肾功能的影响及其作用机制.方法 Wistar大鼠42只,随机分为对照组,缺血5 h组,缺血5 h分别再灌注2、4、8、12 h组,每组7只.检测血清尿素氮(BUN)、肌酐(Cr)及血浆和肾组织匀浆丙二醛(MDA)、超氧化物歧化酶(SOD)水平,光镜观察各组大鼠肾脏及下肢肌肉形态学变化.结果 缺血及再灌注组大鼠BUN水平较对照组高,差异有统计学意义(P<0.05),在I/R4 h组达到最高,随后下降;各组间Cr差异无统计学意义.大鼠血浆MDA水平在对照组与I组,L/R 2 h组,I/R4 h组,I/R 8 h组,I/R 12 h组组间比较差异有统计学意义(P<0.05),血浆MDA水平在I/R 4 h组达到高值,随后下降.大鼠血浆SOD水平在对照组与I/R 4 h组,I/R 8 h组组间比较差异有统计学意义(P<0.05);大鼠肾组织匀浆SOD水平在I/R4 h组与对照组,I组,I/R 2 h组,I/R 8 h组.I/R 12 h组组间比较差异有统计学意义(P<0.05),SOD水平在I/R 4 h组达到低值,随后升高.光镜观察缺血组肾脏及下肢肌肉组织可见轻度损伤,再灌注组肾脏及下肢肌肉组织损伤程度较缺血组重.结论 大鼠肾下腹主动脉阻断后再灌注可造成肾功能异常,与缺血再灌注所激发的自由基合成及释放增多有关.     

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.     

肾缺血/再灌注时肾组织损伤及细胞凋亡的实验研究

目的：检测肾缺血／再灌注不同时问点肾组织、功能损伤及细胞凋亡的变化，探讨细胞凋亡在肾缺血／再灌注损伤中发生的机制。方法：应用苦味酸法和二乙酰一肟反应法测定大鼠肾缺血／再灌注不同时间点血肌酐和尿素氮值检测肾功能变化，用HE染色光镜下观察缺血／再灌注石蜡包埋切片肾组织损伤形态学改变，用酚／氯仿抽提小片断DNA，在琼脂糖电泳上测定不同时间点DNA Ladder及利用原位凋亡检到法观察各时间点TUNEL阳性细胞数检测细胞凋亡情况。结果：肾功能检测发现，缺血45min后血肌酐和尿素氮值明显增高和正方对照差异显(P＜0.05)，再灌注早期上升缓慢，3h后再次增高，组内对比差异显(P＜0．05)。HE染色光镜下观察肾组织细胞以近端肾小管变性为主、坏死轻微，缺血／再灌注各时间点组织损伤变化与肾功能变化规律相一致。琼脂糖电泳和TUNEL检测在缺血45min再灌注3h时可测到DNA Ladder和TUNEL阳性细胞增加，再灌注12h细胞凋亡最明显。结论：肾缺血／再灌注可引起肾组织轻、中度的损伤和明显的肾功能损害；肾缺血／再灌注后期肾组织及功能损伤加重可能与细胞凋亡的发生有关。     

Effect of Ascorbic Acid on Infarct Size in Experimental Focal Cerebral Ischaemia and Reperfusion in a Primate Model

Summary  Temporary occlusion of major cerebral blood vessels occasionally becomes necessary during surgical procedures. Ascorbic acid (Vitamin C) is an important non-enzymatic scavenger of free radicals and its protective effect on the brain in permanent focal cerebral ischaemia has been proven in a primate model of focal cerebral ischaemia [16]. Additional damage caused by reperfusion of the infarcted area has been shown in the rat model [22].  This study was undertaken to study the efficacy of ascorbic acid in decreasing infarct size in ischaemic reperfused brain.  Maccaca radiata monkeys in the treated group were given two grams of ascorbic acid, parentally immediately before clipping the middle cerebral artery and the control group was given placebo. Reperfusion was done after four hours. Mean infarct size in all the three brain slices in the ascorbic acid pretreated group was 7.3%±2.7 and in the placebo group 22.1±6.7 under similar conditions. The mean infarct size in the ascorbic acid pretreated group of monkeys was significantly lower when compared with the placebo group (p=0.0003).     

Oxalate Metabolism in End-Stage Renal Disease: the Effect of Ascorbic Acid and Pyridoxine

Oxalate metabolism was studied in ten patients with end-stagerenal disease. No patient with primary hyperoxaluria was includedin this study. Five patients were on regular haemodialysis andfive patients were on chronic ambulatory peritoneal dialysis(CAPD). Oxalate metabolism was assessed by measurement of plasmaoxa late concentration (P_ox) oxalate metabolic pool size (OxMP),tissue oxalate accumulation rate (TOxA), oxa late productionrate (OxPR) and dialysis clearance of oxalate (DC_ox These observationswere made on three separate occasions in each of the ten patients:initially when the patients were taking a routine ascorbic acidsup plement of 100mg per day; then after a period of I monthwith no ascorbic acid supplement; and then finally after a furtherperiod of I month's treatment with pyridoxine 800 mg daily. The values for P_ox OxMP and TOxA were significantly increasedin all ten patients and in the range observed in some patientswith type I primary hyperoxaluria. There was no significantdifference between immediate pre haemodialysis P_ox and the P_oxin the CAPD patients. The DC was very much greater during haemodialysis(mean 85 mI/mm) than during CAPD (mean 8 mI/mm). The acute fall,in P during haemodialysis was greater than 50% of the immediatepre-haemodialysis concentration. Ascorbic acid in a dose of 100 mg/day had no signifi cant effecton the parameters of oxalate metabolism studied. Pyridoxinein a dose of 800 mg/day produced a significant fall in P_ox inboth haemodialysis and CAPD patients.     

Ascorbic acid prevents ischemia-reperfusion injury in the rat small intestine

Ischemia-reperfusion injury by free radicals and lipid peroxides is observed in various organs. Ascorbic acid (AsA) or glutathione (GSH) in various doses (AsA:2, 0.5, 0.1 mmol/kg, GSH:2 mmol/kg) was intraperitoneally administered to male Wistar rats. The entire small intestines were resected just before ischemia, after ischemia, and after 20 min of reperfusion (n = 7–10 at each time point). At each time point, the specimens were subjected to assays of lipid peroxides, GSH, and glutaminase activity of the tissues; they were also examined histologically. In the AsA group, the production of lipid peroxides after reperfusion was significantly suppressed in a dose-dependent manner, and the ratio of oxidized GSH to total GSH was also significantly low. Tissue glutaminase activity decreased to a lesser extent, and the degree of injury was apparently less marked in the AsA group. This study indicates that AsA acts as an antioxidant against peroxidative tissue injury, possibly by scavenging radicals, preserving reduced GSH, and reducing the peroxidative reaction. Received: 21 June 1996 Received after revision: 8 October 1996 Accepted: 12 November 1996     

抗坏血酸对维持性血液透析患者血清Hepcidin的影响

目的：观察抗坏血酸对维持性血液透析（MHD）患者血清铁调素（Hepcidin）的影响。方法：选择符合条件的MHD患者60例,分为治疗组和对照组各30例。治疗组每日口服抗坏血酸300 mg,共12周,对照组不服用抗坏血酸及其他抗氧化剂。检测两组实验前后血清Hepcidin、血红蛋白（Hb）、白蛋白（Alb）、C反应蛋白（CRP）、铁蛋白（SF）、白细胞介素（IL-6）等相关指标,比较两组指标的变化。结果：两组实验前各项指标差异无统计学意义。治疗组口服抗坏血酸12周后,血CRP、IL-6水平下降,差异有统计学意义（P〈0.05）;Hepcidin、SF、Hb、Alb差异无统计学意义。对照组实验前后各项试验指标差异无统计学意义。结论：口服抗坏血酸在一定程度上降低MHD患者血CRP、IL-6水平,但对Hepcidin未产生显著影响。     

维生素C对糖尿病大鼠肾缺血-再灌注损伤的影响

目的 观察维生素C对链脲佐菌素(STZ)诱导糖尿病大鼠肾缺血-再灌注损伤的影响.方法 32只SD大鼠随机均分为四组:A、B、C组为糖尿病大鼠,B、C组行缺血-再灌注处理,A、B组每天腹腔注射生理盐水0.5 ml,C组注射维生素C 200 mg/kg(0.5 ml),D组为空白对照组.观察血糖、尿素氮(BUN)、肌酐(Cr)、丙二醛(MDA)、超氧化物歧化酶(SOD)、细胞色素C(Cytc)、半胱天冬酶-3(caspase-3)的变化.结果 B组BUN、Cr、MDA含量较C组明显升高(P＜0.05),S0D的活性明显降低(P＜0.05).C组caspase-3和Cytc的表达明显减少,肾小管损伤、坏死显著减轻.结论 维生素C能减轻STZ诱导糖尿病大鼠肾缺血-再灌注损伤的氧化应激,抑制细胞的凋亡及改善肾功能.     

核因子-κB/I-κB传导通路在肝脏缺血再灌注损伤中的作用

目的 探讨核因子(NF)—κB／Ⅰ—κB传导通路在肝脏缺血再灌注损伤中的作用。方法 采用阻断大鼠部分肝血供的缺血再灌注损伤模型，左半肝缺血90min，再灌注分0、1、2、4h等时点。用凝胶滞留电泳方法测定NF—κB的结合活性；应用逆转录—聚合酶链反应(RT—PCR)测定肝组织中肿瘤坏死因子—α(TNF—α)、细胞间粘附因子—1(ICAM—1)mRNA的表达量。结果 肝脏缺血再灌注损伤时NF—κB与其特异性调控序列的结合活性增高且具有时相性。再灌注1～2h NF—κB结合活性增高，4h后开始降低。肝组织中TNF—α、ICAM—1 mRNA表达在再灌注2h后升高。讨论 肝脏缺血再灌注损伤时，NF—κB激活并进入细胞核内，与一些炎症因子基因启动子区特异序列结合，上调TNF—α、ICAM—1 mRNA表达，从而引起肝脏缺血再灌注损伤。     

肢体缺血再灌注损伤的研究进展

由于肢体缺血再灌注损伤的机制复杂，目前尚未完全阐明，现将近年来对肢体缺血再灌注损伤的研究进展综述如下。     

The Protective Effects of Ascorbic Acid against Renal Ischemia-Reperfusion Injury in Male Rats

There is increasing evidence to suggest that toxic oxygen radicals play an essential role in the pathogenesis of ischemia/reperfusion (I/R) injury in the kidney. This study was designed to investigate the effects of ascorbic acid (AA) in I/R-induced renal injury in rats. Thirty two male Sprague-Dawley rats were divided equally into four groups: group 1 (control; dissection of the right renal pedicle without nephrectomy), group 2 (sham operated; unilateral nephrectomy), group 3 (I/R; unilateral nephrectomy?+?I/R); and group 4 (AA+I/R; unilateral nephrectomy and I/R treated with ascorbic acid, 250mg kg^?1 i.p., for one hour prior to ischemia). On the 15th day following nephrectomy, groups 3 and 4 were subjected to 45 min of renal pedicle occlusion followed by 3 h of reperfusion. At the end of the treatment period, kidney samples were taken for histological examination or determination of the renal malondialdehyde (MDA) and glutathione (GSH) levels. Serum creatinine, blood urea nitrogen (BUN), and lactate dehydrogenase (LDH) concentrations were measured for the evaluation of renal function. I/R caused a significant decrease in GSH level, which was accompanied with a significant increase in MDA level of kidney tissues. Similarly, serum BUN and creatinine levels, as well as LDH, were elevated in the I/R group as compared to the control group. In group four, AA treatment reversed all the changes in these biochemical indices, as well as histopathological alterations normally induced by I/R. The findings imply that reactive oxygen species play a causal role in I/R-induced renal injury, and that AA exerts renoprotective effects, probably by radical scavenging and antioxidant activities.     

肝移植缺血再灌注损伤的比较蛋白质组学研究

目的 研究肝移植手术中供体肝组织缺血一再灌注损伤的蛋白质变化规律.方法 2009年3月,对3例肝移植供肝于3个时间点切取肝组织标本进行对照研究:(1)新鲜的供肝组织;(2)经过缺血降温保存后修整完毕,但未经血管吻合的肝脏组织;(3)复流后的供肝组织.通过2DE-MALDI-TOF和质谱技术,对上述3个时间点的蛋白表达作出比较.结果 本研究共分离出1580个蛋白点,其中与缺血再灌注损伤有关的蛋白19个.结合19个蛋白质的功能,对这些蛋白质的变化特征进一步分析.结论 我们发现了与肝移植手术中供肝缺血性损伤和再灌注损伤相关的蛋白质,并首次揭示了这些蛋白质在不同损伤阶段独立的变化规律.     

右美托咪定对上肢缺血再灌注损伤性肺损伤的保护作用

目的观察右美托咪定对上肢缺血再灌注损伤患者肺损伤的保护作用。方法前臂或手部需使用止血带进行手术患者40例,随机分成对照组(C组)和右美托咪定组(D组)2组,各20例。D组在完成肌间沟臂丛神经阻滞后静脉泵注右美托咪定负荷剂量0.5μg/kg,10 min完成,随后以0.5μg/(kg·h)速率静脉泵注直至术毕。C组静脉泵注相同速度和剂量生理盐水。待负荷剂量泵注完成后上止血带,分别在上止血带即刻(T0)、上止血带后1 h(T1)、松止血带后0.5 h(T2)、2 h(T3)、6 h(T4)和24 h(T5)取血样进行血气分析和测定血浆超氧化物歧化酶(SOD)和丙二醛(MDA)浓度。记录动脉血二氧化碳分压(Pa CO2)、动脉血氧分压(Pa O2)。按照公式计算肺泡动脉血氧分压差(PA-a DO2)、呼吸指数(RI)和动脉血/肺泡氧分压比值(a/A比值)。结果与T0比较,2组患者T4时Pa O2、a/A比值下降,PA-a DO2、RI比值上升(P<0.05)。与C组相比,D组在T4时Pa O2、a/A比值增大,PA-a DO2、RI降低(P<0.05)。与TO比较,C组患者T3-5时血浆MDA浓度升高、SOD浓度降低(P<0.05),D组患者T4时血浆MDA浓度升高、SOD浓度降低(P<0.05),但其幅度小于C组。与C组相比,D组患者T3-5时血浆MDA浓度降低、SOD浓度增加(P<0.05)。结论右美托咪定可改善由止血带引起肢体缺血再灌注损伤继发的肺损伤,其可能机制是通过增加体内氧自由基清除剂(SOD)从而减少体内脂质过氧化反应(MDA)达到减少肺组织损伤目的。