Investigation of the renal injury caused by liver ischemia-reperfusion in rats

To explain the mechanism of renal injury caused by liver ischemia-reperfusion, we investigated biochemical and morphological changes in the liver and kidney in rats. After reperfusion following 60 min of liver ischemia, numerous changes were found. The level of serum transaminases and lipid peroxide formation in the liver tissue increased significantly. Electron microscopic studies revealed that most of the hepatocytes had swollen mitochondria and clumping of the nuclear chromatin. The sinusoidal endothelium was disrupted and the sinusoidal lumen was filled with numerous erythrocytes. Blood endotoxin concentration, plasma lipid peroxide levels, and serum -glucuronidase activities were significantly higher than in the control group. Biochemical and morphological renal injury was also observed. Tissue lipid peroxide levels increased in both the kidney and the liver. Microscopic examination revealed damage to the renal tubules, including interstitial edema, dilatation of the lumen, and granular casts derived from necrotic cells in the proximal convoluted tubule. The levels of urinary N-acetyl--d-glucosaminidase (NAG) in the liver ischemia-reperfusion group were also higher than in the control group. These results suggest that the renal injury was caused by an increase in endotoxin, lipid peroxide, and lysosomal enzymes in the blood following the liver injury induced by the ischemia-reperfusion.     

An injury of the liver caused by ischemia-reperfusion in rat liver. Report 2: Relationship between the damage of the liver and during the period of reperfusion]

Liver injury by 30-min ischemia following reperfusion was examined biochemically and histopathologically. A greater increase in the level of LDH was observed after 1-hr reperfusion. However, the level of LDH decreased in proportion to the period of reperfusion, while the levels of GOT and GPT were also increased rapidly and reached its peak at 12 hr following reperfusion and were almost restored to the control level by 48 hr. A similar increase was obtained in the lipid peroxides of the liver. In addition, cyt. P-450 content and NADPH cyt. c reductase activity decreased in proportion to the period of reperfusion up to 12 hr and then recovered by 96 hr. On the other hand, heme oxygenase activity was significantly increased by ischemia-reperfusion. The ischemia-reperfused liver resulted in various morphological changes with the period of reperfusion. The destruction of Disse's space, vacuolization of the cytoplasm and nonviable hepatocytes were observed after 12-hr reperfusion. These results indicate the greatest damages of the liver induced by 30-min ischemia following reperfusion is observed after 12-hr or 24-hr reperfusion. The liver injury by ischemia-reperfusion could be a useful experimental model to develop for future studies.     

Protective effect of ulinastatin against liver injury caused by ischemia-reperfusion in rats.

The effects of ulinastatin (ULN), a human urinary protease inhibitor, on liver injury caused by ischemia-reperfusion were studied in rats. In the liver ischemia-reperfusion model, ULN suppressed the elevation of serum transaminase levels and tissue lipid peroxide levels in the liver. ULN did not exhibit a radical-trapping action on the superoxide and hydroxyl radicals as measured by electron spin resonance (ESR). ULN suppressed formylmethionyl-leucyl-phenylalanine (FMLP) and phorbol myristate acetate (PMA)-induced superoxide production from polymorphonuclear leukocytes (PMNs) as measured by the cytochrome c assay. ULN did not inhibit either xanthine oxidase (XO) activity or the conversion of xanthine dehydrogenase (XDH) to XO during the ischemic period. ULN also strongly protected against the hypotonic hemolysis of rat erythrocytes. These results suggest that ULN's membrane stabilizing action and suppressive effect against PMNs superoxide production might be attributed to its suppressive effect on the liver's lipid peroxidation caused by ischemia-reperfusion.     

Effect of bifemelane hydrochloride on an injury of the liver caused by ischemia-reperfusion in rats

In the liver ischemia-reperfusion model, the lipid peroxide level increased during ischemic periods, while a greater increase was observed during reflow periods. The increase in the cytochrome b5 content was observed during ischemia and reflow periods. On the contrary, the cytochrome P-450 content remained unchanged during ischemic periods, but decreased during reflow periods. Bifemelane suppressed the elevation of the lipid peroxide level, the cytochrome b5 content and the decrease in cytochrome P-450 content during the period of reperfusion.     

Picroliv preconditioning protects the rat liver against ischemia-reperfusion injury

Cell death following ischemia-reperfusion injury is a major concern in clinical issues such as organ transplantation and trauma. The need to identify agents with a potential for preventing such damage has assumed great importance. We have evaluated the efficacy of picroliv, a potent antioxidant derived from the plant Picrorhiza kurrooa, in protecting against hepatic ischemia-reperfusion injury in vivo. Picroliv was fed to male Sprague Dawley rats in a dose of 12 mg/kg once daily by oral gavage for 7 days prior to hepatic ischemia. Ischemia was induced by occluding the hepatic pedicel with a microaneurysm clip for 30 min and reperfusion was allowed thereafter for varying period (15-120 min) by releasing the microaneurysm clip. Picroliv pretreatment resulted in better hepatocyte glycogen preservation and reduced apoptosis. Reduction in apoptosis was associated with decreased mRNA expression of caspase-3 and Fas. Oxidant induced cellular damage as measured by tissue malondialdehyde (MDA) levels was significantly less following picroliv pretreatment. Both a reduction in neutrophil infiltration and an increased level of intracellular antioxidant enzyme superoxide dismutase possibly contributed to the reduction in tissue lipid peroxidation. Tissue inflammatory cytokines level of interleukin-1alpha (IL-1alpha) and interleukin-1beta (IL-1beta) was also lower in picroliv group. Furthermore, picroliv pretreatment resulted in enhanced proliferating cell nuclear antigen (PCNA) immunoreactivity. These studies strongly suggest picroliv to be a promising agent for ameliorating injury following ischemia-reperfusion.     

川芎嗪对大鼠肝脏缺血再灌注损伤的保护作用

目的：研究川芎嗪对大鼠肝脏缺血再灌注损伤的保护作用及其机制。方法：SD大鼠随机分为5组：空白对照组、假手术组、缺血再灌注组、生理盐水组和川芎嗪组。其中空白对照组大鼠直接处死;假手术组开腹后60 min关闭腹腔;缺血再灌注组阻断70%肝血流60 min,再灌注4 h;生理盐水组予腹腔内注射生理盐水8 ml/kg,30 min后阻断70%肝血流60 min,再灌注4 h;川芎嗪组予腹腔内注射川芎嗪80 mg/kg,30 min后阻断70%肝血流60 min,再灌注4 h。速率法测血清丙氨酸氨基转移酶（alanine aminotransferase,ALT）和天冬氨酸氨基转移酶（aspartate aminotransferase,AST）活性,酶联免疫吸附法（ELISA）测血白介素-1（IL-1）、白介素-10（IL-10）和肿瘤坏死因子-α（TNF-α）水平。苏木素-伊红染色观察肝脏病理改变。结果：川芎嗪组血清ALT、AST、IL-1和TNF-α水平均比缺血再灌注组和生理盐水组明显降低（P〈0.05）,而IL-10则明显高于缺血再灌注组和生理盐水组（P〈0.05）。病理结果显示,川芎嗪组大鼠肝细胞损伤较缺血再灌注组和生理盐水组为轻。结论：川芎嗪对大鼠肝脏缺血再灌注损伤具有保护作用,其机制可能与抑制炎性细胞因子生成及促进抗炎细胞因子表达有关。     

正丁酸钠对大鼠肝脏缺血再灌注损伤的保护作用的研究

目的：观察正丁酸钠拮抗高迁移率族蛋白B1（HMGB1）表达对大鼠肝脏缺血再灌注损伤中的保护作用。方法：建立大鼠肝脏缺血再灌注模型．将40只雄性Wistar大鼠随机先分成5组（n-8）：假手术组,缺血组,预处理组、治疗1组、治疗2组。分别于缺血再灌注6h前后给药观察血清AST、ALT、TNF—α水平及肝组织HMGB—1含量变化,并行肝组织病理学检查。结果：缺血再灌注组中HMGB—1的含量高,预处理组、治疗1组、治疗2组这三组中相应时间点的HMGB-1含量、AST、ALT水平、TNF—α含量均较缺血再灌注组中低,预处理组较治疗1组、治疗2组效果显著且肝细胞病理损害较轻。结论：正丁酸钠预处理组对肝脏缺血再灌注损伤具有明显的保护作用。     

Protective effects of etomidate on rat liver underwent hepatic ischemia-reperfusion injury

目的 探讨依托咪酯对大鼠缺血-再灌注(I-R)损伤肝脏的保护作用.方法 雄性SD大鼠40只随机均分为4组:A组,I-R模型对照;B组,I-R加生理盐水2ml · kg-1·h-1处理;C组,I-R加依托咪酯0.3 mg·kg-1·h-1处理;D组,假手术对照.于再灌注后30 min(T1)和60 min(T2)测定肝组织和血浆中内皮素1(ET-1)与一氧化氮(NO)水平以及血清ALT和AST水平,并进行肝组织形态学观察.结果 T1、T2时,A、B、C三组肝组织和血浆中ET-1均高于D组(P＜0.01),但C组低于A、B两组(P＜0.05),同时,肝组织和血清中NO低于D组(P＜0.01),但C组高于A、B两组(P＜0.05).T1、T2时,A、B、C三组血清ALT和AST均高于D组,但C组低于A、B两组(P＜0.05或P＜0.01).肝细胞形态学发生异常改变,C组的肝脏淤血较A、B两组轻,肝细胞变性坏死不明显.结论依托咪酯通过降低ETA-1水平,提高NO水平,改善肝脏微循环障碍,对肝脏I-R损伤有保护作用.     

依托咪酯对大鼠肝缺血-再灌注损伤的保护作用

目的探讨依托咪酯对大鼠缺血-再灌注(I-R)损伤肝脏的保护作用。方法雄性SD大鼠40只随机均分为4组:A组,I-R模型对照;B组,I-R加生理盐水2ml.kg-1.h-1处理;C组,I-R加依托咪酯0.3mg.kg-1.h-1处理;D组,假手术对照。于再灌注后30min(T1)和60min(T2)测定肝组织和血浆中内皮素1(ET-1)与一氧化氮(NO)水平以及血清ALT和AST水平,并进行肝组织形态学观察。结果 T1、T2时,A、B、C三组肝组织和血浆中ET-1均高于D组(P<0.01),但C组低于A、B两组(P<0.05),同时,肝组织和血清中NO低于D组(P<0.01),但C组高于A、B两组(P<0.05)。T1、T2时,A、B、C三组血清ALT和AST均高于D组,但C组低于A、B两组(P<0.05或P<0.01)。肝细胞形态学发生异常改变,C组的肝脏淤血较A、B两组轻,肝细胞变性坏死不明显。结论依托咪酯通过降低ET-1水平,提高NO水平,改善肝脏微循环障碍,对肝脏I-R损伤有保护作用。     

Differential effects of caspase inhibitors on the renal dysfunction and injury caused by ischemia-reperfusion of the rat kidney

Caspase activation has been implicated in the development of ischemia-reperfusion injury. Here, we investigate the effects of different caspase inhibitors on the renal dysfunction and injury caused by ischemia-reperfusion of the rat kidney. Bilateral clamping of renal pedicles (45 min) followed by reperfusion (6 h) caused significant renal dysfunction and marked renal injury. Caspase-1 inhibitor II (N-acetyl-L-tyrosyl-L-valyl-N-[(1S)-1-(carboxymethyl)-3-chloro-2-oxo-propyl]-L-alaninamide, Ac-YVAD-CMK, 3 mg/kg, administered i.p.) significantly reduced biochemical and histological evidence of renal dysfunction and injury. However, although caspase-3 inhibitor I (N-acetyl-L-aspartyl-L-glutamyl-N-(2-carboxyl-1-formylethyl]-L-valinamide, Ac-DEVD-CHO, 3 mg/kg, administered i.p.) produced a significant improvement of renal (glomerular) dysfunction (reduction of serum creatinine levels), it was not able to reduce tubular dysfunction and injury. Furthermore, the pan-caspase inhibitor caspase inhibitor III (N-tert-butoxycarbonyl-aspartyl(OMe)-fluoromethylketone, Boc-D-FMK, 3 mg/kg, administered i.p.) did not reduce renal dysfunction and injury. Both caspase-1 and -3 inhibitors markedly reduced the evidence of oxidative and nitrosative stress in rat kidneys subjected to ischemia-reperfusion. Overall, these results demonstrate that inhibition of caspase-1 reduces renal ischemia-reperfusion injury to a greater extent than caspase-3 inhibition, supporting the notion that the mode of acute cell death in our model of renal ischemia-reperfusion is primarily via necrosis. Furthermore, our finding that a pan-caspase inhibitor did not reduce the renal dysfunction and injury suggests that activation of some caspases during ischemia-reperfusion could provide protection against acute ischemic renal injury. Overall, these results demonstrate that inhibition of caspase-1 activity reduces renal ischemia-reperfusion injury and that this therapeutic strategy may be of benefit against ischemic acute renal failure.     

美索巴莫致急性肝损伤

1例61岁男性患者因腰椎间盘突出症口服美索巴莫0.5 g,1次/d。6 d后,腰痛缓解,自行停药。6d后,因腰痛加重再次服用相同剂量美索巴莫。再次用药后第7天,患者出现皮肤黄染、尿色加深,伴有食欲减退。6 d后,因厌食而自行停药。实验室检查：丙氨酸转氨酶（ ALT）1369 U/L,天冬氨酸转氨酶（ AST）1198 U/L,直接胆红素（ DBil）87.1μmol/L,间接胆红素（ IBil）75.4μmol/L。诊断为药物性肝损伤。给予谷胱甘肽（1.8 g,1次/d）和异甘草酸镁（0.1 g,1次/d）静脉滴注。1 d后复查：ALT 1331 U/L,AST 503 U/L,DBil 73.9μmol/L,IBil 68.9μmol/L。13 d后肝功能复查：ALT 131 U/L,AST 71 U/L,DBil 34.5μmol/L,IBil 45.0μmol/L。改为口服谷胱甘肽（0.4 g,3次/d）和甘草酸二铵（0.15 g,3次/d）。1个月后随访,患者黄染消退,ALT 19 U/L,AST 11 U/L,DBil 1.3μmol/L,IBil 11.4μmol/L。     

Role of kupffer cells in cold/warm ischemia-reperfusion injury of rat liver

The mechanisms of liver injury from cold storage and reperfusion are not completely understood. The aim of the present study was to investigate whether the inactivation of Kupffer cells (KCs) by gadolinium chloride (GdCl3) modulates ischemia-reperfusion injury in the rat liver. Hepatic function was assessed using an isolated perfused rat liver model. In livers subjected to cold storage at 4 degees C in University of Wisconsin solution for 24 hrs and to 20 min rewarm-ing ischemia, oxygen uptake was markedly decreased, Kupffer cell phagocytosis was stimulated, releases of purine nucleoside phosphorylase and lactate dehydrogenase were increased as compared with control livers. Pretreatment of rats with GdCl3, a selective KC toxicant, suppressed Kupffer cell activity, and reduced the grade of hepatic injury induced by ischemia-reperfusion. While the initial mixed function oxidation of 7-ethoxycoumarin was not different from that found in the control livers, the subsequent conjugation of its meta-bolite to sulfate and glucuronide esters was suppressed by ischemia-reperfusion. GdCl3 restored sulfation and glucuronidation capacities to the level of the control liver. Our findings suggest that Kupffer cells could play an important role in cold/warm ischemia-reperfusion hepatic injury.     

A novel antioxidant non-steroidal anti-inflammatory agent protects rat liver against ischemia-reperfusion injury

Liver ischemia followed by reperfusion is an important and common clinical event. A major mechanism is leukocyte adhesion to endothelium followed by release of reactive oxygen metabolites. The aim of this study was to determine the effects of a novel antioxidant ethylenediamine derivative with anti-inflammatory properties (compound IA) on an imitated clinical setting of acute hepatic ischemia-reperfusion injury. Eight groups of rats were subjected to a model of hepatic ischemia that was produced by occluding for 30 min the portal vein and hepatic artery. At the end of ischemia, compound IA was administered intravenously and the clamps were removed allowing reperfusion for 60 min or 24 h. The effect of compound IA was evaluated by histopathological examination, lipid peroxidation and plasma levels of liver enzymes. Administration of compound IA resulted in significantly less histological damage in liver tissue after 30-min ischemia followed by 60-min and 24-h reperfusion. Ischemia followed by 60 min of reperfusion increased lipid peroxidation compared to the sham-operated and the non-ischemic group. This increase was attenuated in the group treated with compound IA. Serum enzyme levels were significantly higher in the reperfusion groups compared to the non-ischemic groups and diminished after treatment. Compound IA exerted a protective effect on hepatic reperfusion injury in rats. Compound IA is believed to act by means of its potent antioxidant and anti-inflammatory activities.     

The role of thiols in liver ischemia-reperfusion injury

Thiol-containing compounds have an essential role in many biochemical reactions due to their ability to be easily oxidised and then quickly regenerated. Main representatives are glutathione, lipoic acid and thioredoxin which are synthesised de novo in mammalian cells. N-acetylcysteine and Bucillamine are synthetic thiols which have been administered in experimental and clinical studies for treatment of conditions associated with oxidative stress. Ischemia and reperfusion (I/R) injury is characterised by significant oxidative stress, characteristic changes in the antioxidant system and organ injury leading to significant morbidity and mortality. I/R occurs in a variety of clinical settings such as liver resection, organ transplantation, haemorrhagic shock with fluid resuscitation, heart surgery, myocardial infarction followed by reperfusion and laparoscopic surgery. In these circumstances, the administration of antioxidant agents such as thiols, could provide protection from the harmful effects of I/R injury. However, the ability of thiol compounds to reduce free radicals is associated with the formation of thiyl radicals and the rate and efficiency of removal of thiyl radicals has a critical effect on antioxidant or prooxidant actions of thiols in the cells. The aim of this review is to present the mechanisms by which thiols act as antioxidants and signalling molecules and the experimental and clinical evidence regarding their role in I/R injury with a particular emphasis on liver I/R. The current evidence suggests that thiols ameliorate I/R injury and that their clinical significance should be further evaluated in large scale randomised clinical trials.     

The role of prostaglandins in liver ischemia-reperfusion injury

Ischemia reperfusion (IR) of the liver is a multifactorial process that, at least in part, is responsible for the morbidity associated with major liver surgery under occlusion of the portal triad with the Pringle maneuver, total vascular exclusion or after liver transplantation. Surgeons are confronted with IR injury (IRI) more often than they anticipate. Although the human body has its own defense system, understanding the pathophysiology of IRI is essential for the surgeon in preventing and/or treating the reperfusion injury in common clinical practice. Several endogenous mechanisms exist to overcome IRI and a large number of pharmacological agents have also been found to confer protection against ischemic injury in the liver. They either blocked the injurious pathways directly or they subjected the liver to preconditioning. Prostaglandins (PGs) are a group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase (COX) pathway. They are short-lived, hormone-like chemicals that regulate cellular activities on a moment-to-moment basis and are produced in most tissues of the body, although the liver has emerged as the major organ participating in the synthesis, degradation and elimination of arachidonate products of systemic origin. PGs are released through the prostaglandin transporter on the cell's plasma membrane. During the last decade intensive work on the cytoprotective effects of PGs on livers suffering from IRI have been well documented. Prostaglandins confer their protective effects on IR-injured livers mainly by inhibiting the generation of reactive oxygen species, preventing leukocyte migration, reducing the synthesis or production of membrane degradation products, improving hepatic insulin and lipid metabolism, and regulating the production of inflammatory cytokines and cell adhesion molecules. Production of PGs have been found essential also soon after partial hepatectomy for hepatocyte proliferation.     

单次剂量照射制备大鼠放射性肝纤维化模型的建立与评价

目的评价单次30 Gy照射制备大鼠放射性肝纤维化模型的可行性、科学性及实用性。方法清洁SD雄性大鼠48只,随机分为照射组（A组）40只、对照组（B组）8只。VARIN 21-EX直线加速器对A组大鼠右肝进行单次照射（30 Gy/次）,于照射后第4、8、12、26周处死,每时相点处死8只,B组于第4周末处死。观察大鼠活体外观及肝脏的大体标本,检测大鼠血清中AST、ALT活性,ELISA法测大鼠血清中TGF-β1、HA、PC-Ⅲ、LN含量、HE染色于光镜下观察肝脏组织病理改变、MASSON染色观察大鼠肝脏组织胶原沉积改变;碱水法检测大鼠肝脏组织中Hyp含量,免疫组化法测肝脏组织TGF-β1蛋白表达情况。结果与对照组（B组）比较,A组受照射肝组织表现出放射性肝炎及肝纤维化,照射组大鼠血清中AST,ALT酶活性和TGF-β1水平自第4周明显升高（P〈0.05或P〈0.01）,分别于第8周和第12周达到高峰;照射组大鼠血清中HA、PC-Ⅲ、LN含量和肝脏组织中Hyp含量于照射后第4周显著升高（P〈0.05或P〈0.01）,一直呈上升趋势,照射后26周值最高;照射组大鼠肝脏组织中TGF-β1蛋白表达于照射后第4周也明显升高（P〈0.05）,照射后第12周达到高峰,第26周开始下降。光镜下可见肝脏病变呈慢性进行性肝纤维化改变。结论单次剂量照射制备的大鼠放射性肝纤维化模型稳定可靠,动物死亡率较低,可以用于实验研究。     

The protective role of steroids in ischemia-reperfusion injury of the liver

Liver ischemia-reperfusion injury occurs in a number of clinical settings, including liver surgery, transplantation, and circulatory shock, leading to significant morbidity and mortality. There is a substantial evidence that hepatic ischemia-reperfusion injury results from an intense inflammatory response initiated by oxidative stress in the liver parenchyma during reperfusion. The anti-inflammatory effects of glucocorticosteroids (GCs) have been known for decades and have found extensive therapeutic use in a wide range of clinical situations associated with organ ischemia. Based on their biological effects, routine perioperative GCs administration has been advocated to reduce hepatic ischemic injury. However, the use of GCs in hepatic surgery remains controversial and clinical benefits are still uncertain. The aim of this review is to present the experimental and clinical evidence about the role of GCs in modulating hepatic ischemia-reperfusion injury.     

硫普罗宁治疗化疗药物性肝损伤临床观察

目的：观察硫普罗宁治疗化疗药物所致轻度肝损伤的疗效和安全性。方法：将化疗后有轻度肝损伤的60例恶性肿瘤患者随机分为治疗组和对照组各30例,对照组以肌苷0．6g,维生素C 2．0g,维生素B6 0．2g加5％葡萄糖溶液中静脉滴注,每天1次,连续治疗7天;治疗组除上述治疗外。另以硫普罗宁0．2g加5％葡萄糖液中静脉滴注,每天1次,连续治疗7天。同时分别监测肝功能指标谷丙转氨酶（ALT）、谷草转氨酶（AST）、总蛋白（TP）、总胆红素（TBi）、总胆汁酸（TBA）等,并进行比较。结果：治疗组较对照组在肝功能复常方面显示良好的治疗效应,使转氨酶明显下降,治疗组与对照组有效率比较差异有显著性（P〈0．01）。结论：短期临床研究资料提示硫普罗宁治疗化疗药物所致轻度肝损伤,可明显改善肝脏功能,不良反应少,疗效显著,保持化疗连续性。     

术前扩容对预防妇科腹腔镜致缺血再灌注肝损害的研究

目的 探讨腹腔镜术前扩容与预防经妇科腹腔镜手术所致肝功能损害的相关性.方法 将我院80例妇科腹腔镜手术患者随机分为术前扩容治疗组(Ⅰ组)和非术前扩容治疗组(Ⅱ组),每组40例;检测并对比各组患者术后肝脏缺血再灌注各个时点(T=1h、3h、6h、12h)肝功能(丙谷氨酸转氨酶ALT、天门冬氨酸转氨酶AST)及缺血再灌注损伤标记物脂质过氧化物丙二醛(MDA)在缺血再灌注期内的水平变化情况.结果 Ⅱ组肝脏缺血再灌注各个时点( T=1 h、3h、6h、12h)的肝功能血清ALT、AST水平及缺血再灌注损伤标记物MDA均明显高于Ⅰ组(P＜0.05);各组血清ALT、AST及MDA水平在缺血再灌注期均呈增高趋势,且在再灌注6h时达高峰,但在12h时有显著回落趋势(P＜0.05);与Ⅱ组相比,Ⅰ组在缺血再灌注期内的ALT、AST及MDA水平等实验室检查指标波动相对平稳,两组结果差异具有统计学意义(P＜0.05).结论 术前扩容可有效保护腹腔镜手术患者术后肝脏缺血再灌注期的肝功能,是行之有效的预防妇科腹腔镜手术肝功能损伤的治疗措施.