Sequence of reperfusion influences ischemia/reperfusion injury and primary graft function following porcine liver transplantation.

The impact of 3 different reperfusion sequences following orthotopic liver transplantation (OLT) in pigs were evaluated. The reperfusion technique commonly performed is primary portal in order to shorten warm ischemic times (WITs). Experimental and clinical data, usually comparing 2 out of 3 possible reperfusion sequences, provide controversial results. OLT was performed in 24 pigs randomized into 3 groups: primary arterial (A), simultaneous (SIM), and primary portal (P) reperfusion. Hemodynamics were continuously monitored and reperfusion injury and primary graft function were assessed by standard serum parameters, histopathological findings, immunohistochemistry for heme oxygenase 1 (HO-1), and heat shock protein 70 (HSP 70). Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and gamma-glutamyl transpeptidase (gammaGT) following reperfusion were significantly increased for group A when compared to groups SIM and P. Hemodynamics showed significant differences after reperfusion compared to physiological data; differences in group comparisons were not significant. The bile production/100 g liver/hr was significantly higher for group SIM (1.15 mL) compared to group P (0.66 mL) and group A (0.62 mL). Histology and immunohistochemistry significantly correlated with functional results and outcome. Histological score was best for group SIM and worst for group A. HSP 70, being visualized mainly in the hepatocytes, showed higher expression for groups SIM and P. Inversely, HO-1, found in perisinusoidal cells, showed highest expression after primary arterial reperfusion. In conclusion, although associated with a 10-minute longer warm ischemic time, simultaneous reperfusion causes the least reperfusion injury with superior primary transplant function. Primary arterial reperfusion showed the worst overall outcome and highest degree of HO-1 expression.     

In Vitro Negative Inotropic Effect of Plasma Collected at the Time of Reperfusion in Humans undergoing Liver Transplantation

Background: During orthotopic liver transplantation (OLT), acute depression of myocardial contractility has been suspected at the time of the graft reperfusion.

Methods: The authors tested the hypothesis that plasma collected at the time of reperfusion in OLT patients exerted a negative inotropic effect on isolated rat myocardium. Plasma from 13 OLT patients was collected either before surgical incision (group 1, n = 8) or 3-5 min after vena cava and portal vein unclamping (group 2, n = 9). Six patients had their pre-and postincision plasma analyzed. A postreperfusion syndrome was observed in 3 of 13 patients. Left ventricular rat papillary muscles were studied at baseline (T0), 30 min after the addition of plasma (T30), and 60 min after the addition of plasma (T60). The authors recorded contraction parameters (maximum unloaded shortening velocity [Vmax], peak extent of systolic shortening at preload [Delta L], maximum active isometric tension [AFi], positive peak tension derivative [+dFi/dt], time-to-peak shortening [TPS], and time-to-peak force [TPF]) and relaxation parameters (maximum lengthening velocity at preload [V1], negative peak tension derivative [-dFi/dt], index of load sensitivity of relaxation [tRi]).

Results: In group 1, contraction parameters remained unchanged, with the exception of a decreased Vmax at T30 and AFi at T60 (each P <0.05). In group 2, all contraction parameters were significantly decreased at T30 and at T60, with the exception of AFi at T60. Both types of plasma decreased V1 and altered tRi at T30 and T60, whereas only reperfusion plasma decreased -dFi/dt at T30 and T60. At T30, Delta L, -dFi/dt, and tRi were significantly more impaired in group 2 than in group 1. There was no relationship between inotropic changes and mean arterial pressure decrease at the time of reperfusion.     

The effect of methylene blue on the hemodynamic changes during ischemia reperfusion injury in orthotopic liver transplantation

After graft reperfusion in orthotopic liver transplantation (OLT), ischemia reperfusion syndrome (IRS) is characterized by persistent hypotension with a low systemic vascular resistance. Methylene blue (MB) has been used as a vasopressor in sepsis and acute liver failure. We investigated the effect of MB on IRS during OLT. Thirty-six patients undergoing elective OLT were randomized to receive either a bolus of MB 1.5 mg/kg before graft reperfusion, or normal saline (placebo). We recorded hemodynamic variables, postoperative liver function tests, and time to hospital discharge. Blood samples were analyzed for arterial lactate concentration, cyclic 3',5'-monophosphate, and plasma nitrite/nitrate concentrations. The MB group had higher mean arterial pressure (P = 0.035), higher cardiac index (P = 0.04), and less epinephrine requirement (P = 0.02). There was no difference in systemic vascular resistance or central venous pressure. Serum lactate levels were lower at 1 h after reperfusion in MB patients, suggesting better tissue perfusion (P = 0.03). In the presence of MB, there was a reduction in cyclic 3',5'-monophosphate (P < 0.001), but not plasma nitrites. Postoperative liver function tests and time to hospital discharge were the same in both groups. MB attenuated the hemodynamic changes of IRS in OLT acting via guanylate cyclase inhibition. IMPLICATIONS: Methylene blue attenuates the hemodynamic changes of the ischemia reperfusion syndrome in liver transplantation, and this effect involves guanylate cyclase inhibition.     

Sequential and simultaneous revascularization in adult orthotopic piggyback liver transplantation.

The aim of the study was to assess whether there is a difference in outcome after sequential or simultaneous revascularization during orthotopic liver transplantation (OLT) in terms of patient and graft survival, mortality, morbidity, and liver function. The study population consisted of 102 adult patients with primary full-size piggyback OLT transplanted between January 1998 and December 2001. In 71 patients (70%) the grafts were sequentially reperfused after completion of the portal vein anastomosis and subsequent arterial reconstruction was performed (sequential reperfusion [SeqR] group). In 31 patients (30%) the graft was reperfused simultaneously via the portal vein and hepatic artery (simultaneous reperfusion [SimR] group). Patient and graft survival at 1, 3, and 6 months and at 1 year did not differ between the SeqR group and the SimR group. The red blood cell (RBC) requirements were significantly higher in the SimR group (5.5 units; range 0-20) in comparison to the SeqR group (2 units; range 0-19) (P = 0.02). Apart from a higher number of biliary anastomotic complications and abdominal bleeding complications in the SimR group in comparison to the SeqR group (13% vs. 2% and 19% vs. 6%, respectively; P = 0.06), morbidity was not different between the groups. No differences between the groups were observed regarding the incidence of primary nonfunction (PNF), intensive care unit stay, and acute rejection. This was also true for the severity of rejections. Postoperative recuperation of liver function was not different between the groups. In conclusion, no advantage of either of the 2 reperfusion protocols could be observed in this analysis, especially with respect to the incidence of ischemic type biliary lesions (ITBL).     

Remote Ischemic Conditioning on Recipients of Deceased Renal Transplants Does Not Improve Early Graft Function: A Multicenter Randomized,Controlled Clinical Trial

Delayed graft function is a frequent complication following deceased donor renal transplantation, and is closely related to ischemia–reperfusion injury. Experimental and clinical studies have shown protection by remote ischemic conditioning (RIC). We hypothesized that recipient RIC before kidney graft reperfusion reduces the time to graft recovery. This multicenter, blinded, randomized, controlled clinical trial included 225 adult recipients of renal transplants from deceased donors at four transplantation centers in Denmark, Sweden, and the Netherlands. Participants were randomized 1:1 to RIC or sham‐RIC. RIC consisted of 4 × 5‐min thigh occlusion by an inflatable tourniquet each followed by 5‐min deflation, performed during surgery prior to graft reperfusion. The tourniquet remained deflated for sham‐RIC. The primary endpoint was the estimated time to a 50% decrease in baseline plasma creatinine (tCr50) calculated from plasma creatinine measurements 30 days posttransplant or 30 days after the last, posttransplant dialysis. No significant differences were observed between RIC and sham‐RIC‐treated patients in the primary outcome median tCr50 (122 h [95% confidence interval [CI] 98–151] vs. 112 h [95% CI 91–139], p = 0.58), or the number of patients receiving dialysis in the first posttransplant week (33% vs. 35%, p = 0.71). Recipient RIC does not reduce the time to graft recovery in kidney transplantation from deceased donors. ClinicalTrials.gov: NCT01395719.     

Heterotopic vs. orthotopic liver transplantation for chronic liver disease: a case-control comparison of short-term and long-term outcomes.

Between 1986 and 1990 we performed heterotopic liver transplantation (HLT) in 17 patients with chronic liver disease. In spite of theoretical advantages and favorable short-term results, we abandoned HLT because of doubts about the long-term outcome and the improved results of standard orthotopic liver transplantation (OLT). There are, however, no studies comparing the long-term survival after HLT and OLT for chronic liver disease. We performed a case-control study of HLT vs. OLT, with long-term patient and graft survival as the main outcome measures. Known confounders and differences in baseline characteristics between HLT and OLT patients were corrected for. At 1 year, 5 of the 17 HLT patients had died, compared with 9 of the 34 OLT patients (relative risk [RR], 1.15; 95% confidence interval [CI], 0.33-4.02; P = 0.83). After correction for confounders, the long-term risk of graft failure (RR, 18.0; 95% CI, 1.5-223.5; P = 0.02) and of death (RR, 5.2; 95% CI, 0.8-34.8; P = 0.09) was higher after HLT than after OLT. The main causes of graft loss and death at more than 1 year after HLT were de novo malignancies and a variety of biliary complications. In conclusion, our data, from 1 of the largest single-center series of HLTs available, showed no significant difference between HLT and OLT in 1-year survival. However, the long-term outcome of HLT was inferior. HLT cannot be recommended as an alternative to OLT for any of the indications we studied, even though only 1 of the late deaths was definitely related to the heterotopic technique.     

Coagulation disorders during orthotopic liver transplantation

Coagulation disorders have been noted during orthotopic liver transplantation (OLT) especially just after reperfusion of the grafted liver. This study was undertaken to clarify the coagulation disorders following reperfusion of the liver graft. OLT was carried out in adult mongrel dogs using a cuff technique. Fresh and 24-hour preserved livers were grafted. Platelet count (P1), activated partial thromboplastin time (A-PTT), prothrombin time (PT) and plasma fibrinogen levels (Fng) were measured before and after OLT. Next perfusate obtained from fresh livers or preserved livers for 24-hours or 48-hours was determined for their ability of inducing coagulation disorders when infused in untreated dogs, and was also tested for their activity of platelet aggregation, tissue thromboplastin (F-III), and plasminogen activator (PA). All dogs which received preserved livers showed a marked coagulation disorders including a decrease in P1 and Fng, and prolongation of A-PTT and PT, but the dogs with fresh liver grafts did not. Infusion of the perfusate collected from a perfusion of the preserved liver induced similar coagulation disorders in untreated dogs. The perfusate obtained from the preserved liver showed significant increased F-III activity as compared with that from fresh liver. On the other hand, neither direct platelet aggregation activity nor PA activity was seen or very low if any. These results indicate that F-III liberated from a damaged liver is responsible for the coagulation disorders after reperfusion of the graft in liver transplantation.     

Correlation between von Willebrand factor levels and early graft function in clinical liver transplantation

Cold preservation/reperfusion leads to sinusoidal endothelial cell (SEC) activation and damage in nearly every liver transplantation; the extent of these changes influences early graft function. Upon reperfusion, activated SEC show increased expression of adhesion molecules, including von Willebrand factor (vWF) which is released into the circulation. This study was designed to evaluate the levels of vWF measured in the caval effluent and correlate these findings with known markers of SEC damage and early graft function. Data were obtained from 35 patients undergoing orthotopic liver transplantation (LTx). Two samples were taken from each patient for measurement of vWF: a) from the portal vein immediately prior to reperfusion; and b) from the first 50 ml of the caval effluent. Commercial assays were used to measure vWF, as well as hyaluronic acid (HA), thrombomodulin (TM), IL-1β, IL-6, IL-8 and TNF-α. Patients were divided into two groups based on early graft function. Poor early graft function (PEGF) was defined as a peak aspartate transaminase (AST) or alanine transaminase (ALT) level> 2500 U/L during the first three postoperative days (POD) and a prothrombin time (PT)> 16 s on POD 2 (n=8). The remaining 27 patients had good early graft function (GEGF). In patients with GEGF, vWF levels dropped significantly between the two time points. This change was not observed in those with PEGF. A positive linear correlation was observed in the PEGF group between vWF and HA and IL-6. The different pattern of change in vWF between the two groups, as well as the positive correlation between HA, IL-6 and vWF in PEGF, suggest that vWF may be a useful marker of early graft function.     

Temporary intraoperative porto‐caval shunt: useless or beneficial in piggy back liver transplantation?

The role of intraoperative porto‐caval shunts in orthotopic liver transplantation (OLT) is controversial. Aim of this study was to analyze the effects of an intraoperative, porto‐caval catheter‐shunt on graft function and survival following cava sparing OLT. Four hundred and forty‐eight piggy back liver transplantations with or without a temporary spontaneous porto‐caval shunt between 1997 and 2010 were analyzed (shunt n = 274 vs. no shunt n = 174). Lab MELD scores and donor risk indices (DRI) were calculated. Hepatic injury (ALT, AST), ‐function (bilirubin, prothrombin ratio), postreperfusion liver blood flow and graft survival were registered [mean follow‐up: 50.5 (0–163.0) months]. The impact of a shunt on graft survival was determined using multivariate analysis. Usage of a porto‐caval shunt was associated with reduced hepatic injury (ALT, AST), whereas graft function was not affected. The shunt group showed a significantly increased portal venous blood flow after reperfusion. Retransplantation rate was decreased (7.7% vs. 20.1%, P = 0.001) and long‐term graft survival was significantly increased with a porto‐caval shunt (hazard ratio 2.1, P < 0.001). This effect was even more pronounced for marginal organs. Usage of intraoperative porto‐caval catheter‐shunts is beneficial in cava sparing OLT and is associated with reduced ischemia‐reperfusion injury and improved organ survival in particular for recipients of marginal organs.     

A review of aprotinin in orthotopic liver transplantation: can its harmful effects offset its beneficial effects?

Blood transfusion can adversely affect patient outcome and graft survival in orthotopic liver transplantation (OLT). With this respect, prophylactic aprotinin administration decreases blood loss, transfusion requirements, and the hemodynamic changes associated with graft reperfusion in patients undergoing OLT. However, data indicate limiting the use of aprotinin in OLT: (a) clinical, biological, echocardiographic, and postmortem findings recorded in patients with chronic liver disease or undergoing OLT suggest that a continuous prothrombotic state exists in these patients. Whether the inhibition of fibrinolysis associated with aprotinin therapy will expose some patients to untoward thrombosis is questionable; (b) aprotinin does not appear to alter postoperative outcome in patients undergoing OLT; (c) aprotinin decreases blood transfusion requirements only when surgery is associated with significant blood loss. However, at the present time, median transfusion requirements of 2 to 5 red blood cell units are required in OLT.     

Presence of a nitric oxide synthase inhibitor in the graft efflux during reperfusion in human liver transplantation

Involvement of the nitric oxide (NO) system in complications following human orthotopic liver transplants (OLT) has been reported, but the contribution of the graft to the modulation of the NO system during reperfusion in normal OLT has not been characterized. We have studied the contribution of the graft efflux to the modulation of the NO system in 20 consecutive OLT. We evaluated its effects on isolated vascular reactivity of the rabbit and on rat cultured macrophages stimulated with lipopolysaccharide (LPS). In none of the donor liver biopsies was expression of inducible NO synthase (iNOS) activity by Northern or Western blot analysis found. Graft efflux after the onset of liver reperfusion, but not pre-transplant patient plasma, reversibly inhibited the acetylcholine-induced relaxation of norepinephrine-contracted rabbit aortic rings. Moreover, graft efflux reversibly inhibited NO production in rat macrophages treated with LPS, as evidenced by both a decrease in nitrite plus nitrate formation and a decrease in the production of [14C]citrulline from [14C]arginine. Addition of a 10% dilution of graft efflux to cultured rat macrophages incubated with LPS increased iNOS mRNA levels, suggesting direct inhibition of the enzyme but not of its expression. These results cannot be ascribed to the depletion of arginine the iNOS substrate since they can be reproduced even in the presence of an excess (10 mM) of exogenously added arginine. No correlation was found between the iNOS inhibitory activity in each sample and the corresponding clinical parameters related to either the graft function after the OLT or the existence of post-reperfusion syndrome. Our results indicate the existence of a soluble factor in the graft efflux from human OLT that reversibly and unspecifically inhibits NOS activity. Its involvement in the physiology and/or pathology of human liver diseases deserves further study.     

Xanthine oxidoreductase and preservation injury in human liver transplantation

BACKGROUND: Preservation injury is a major cause of primary graft dysfunction in liver transplantation (LT). Oxidative damage is considered to be the first event leading to graft damage. Xanthine oxidoreductase (XOR) and neutrophil activation, two sources of reactive oxygen species, could play a role in the development of graft dysfunction. METHODS: We determined activities of XOR forms, polymorphonuclear elastase (PMN-E), aminotransferases, and hyaluronic acid in plasma of 20 patients undergoing LT. Samples were taken from the radial artery (RA) before the anhepatic phase; from the portal vein (PV) before reperfusion; from graft caval effluent (CE) at reperfusion; and from RA, PV, and the hepatic vein (HV) 10 and 90 min postreperfusion. RESULTS: The graft, but not recipient bowel, released XOR into blood (XOR in CE, median, 61.2 mU/g protein [range, 1.9-160.4 vs. undetectable in PV before reperfusion). Circulating XOR was transformed from dehydrogenase to reversible oxidase (XOrev) (XOrev-to-XOR ratio, 48.1% in CE and 65.1% in HV 90 min postreperfusion). Neutrophil activation was detected in the recipients before reperfusion, and in liver at early post-reperfusion (median PMN-E was 0.85 microg/g protein [range, 0.01-1.58] in RA before the anhepatic phase; 2.22 microg/g protein [range, 0.20-5.88] in PV prereperfu-sion; and 3.60 microg/g protein [range, 0.48-6.78] in HV 10 min postreperfusion). XOR, but none of the other markers, was higher in the CE of patients with moderate primary graft dysfunction than in those with slight primary graft dysfunction. CONCLUSIONS: XOR release and neutrophil activation are produced during LT, and they are potentially injurious mechanisms associated with this therapy.     

前列地尔促进移植肝功能早期恢复的临床研究

目的　探讨前列地尔对术后早期移植肝功能恢复的影响。方法　对 6例肝移植患者从术中开始通过中心深静脉用微量泵给予前列地尔 (治疗组 ) ,术后同法持续 2 4h给予 ,拔除中心静脉插管后通过外周静脉缓慢输注 ,直至术后 2 0d ;另有 4例除不用前列地尔外 (对照组 ) ,其余处理同治疗组。观察两组患者术后 2 1d内的血清丙氨酸转氨酶 (ALT)、天冬氨酸转氨酶 (AST)、总胆红素 (TBil)和直接胆红素 (DBil)水平 ,记录胆汁引流量 ;记录各例术后在重症监护病房的留置时间。结果　术后第 1d两组患者的ALT和AST水平均显著升高 ,但治疗组显著低于对照组 (P <0 .0 1) ,3～ 5d后前述指标均迅速恢复至正常水平 ;两个组术后血清TBil和DBil均开始缓慢升高 ,但治疗组的水平明显低于对照组 (P <0 .0 5 ) ,且升高持续时间也短于对照组 (P <0 .0 5 ) ;治疗组的胆汁引流量显著多于对照组 (P <0 .0 5 ) ,需要重症监护的时间显著短于对照组 (P <0 .0 1)。结论　术后早期应用前列地尔对促进移植肝功能的早期恢复有积极意义。     

肝移植围手术期凝血功能的变化及调控措施

目的探讨同种异体原位肝移植围麻醉期预处理对凝血功能的影响。方法18例ASAⅢ—Ⅳ级因终末期肝病而行原位肝移植的患者,术前及麻醉诱导后进行预处理,并在不同时期采血检测凝血酶原时间（PT）、活化的部分凝血酶原时间（APTT）、纤维蛋白原（FIB）、D-二聚体（D—dimer）、血小板（PLT）及血清钙离子浓度并进行动态观察。同时应用SONOCLOT凝血及血小板功能分析仪对凝血与血小板功能进行定性分析,记录术中出血量及输血量。结果术中PT、APTT逐渐延长,门脉开放初期达到高峰,新肝再灌注后PT、APTT又逐渐缩短;D—dimer总体上呈现逐渐增加的趋势,再灌注后逐渐下降,但始终高于术前水平。大多数病人全血凝固时间（ACT）在手术开始前即开始延长,新肝期最为突出,新肝后期逐渐缩短。凝结速率（CR）新肝期明显减慢,以后逐渐恢复。血小板功能（PF）在新肝初期最差,到术毕明显恢复。结论肝移植术中的早期预处理,并适时个体化调整有利于改善凝血功能障碍,维持术中的相对稳定,减少术中术后出血和输血。     

The effect of in vitro recombinant factor VIIA on coagulation parameters for blood taken during liver transplantation

Recombinant factor VIIa (rFVIIa) has been utilized in pilot studies in orthotopic liver transplantation (OLT) when administered to patients at doses of 68.37 microg/kg and 80 microg/kg. Although some effectiveness in normalizing measurements of coagulation has been demonstrated, the optimal dose for patients undergoing OLT has not been established. This study evaluated the effects of an in vitro equivalent dose of 120 microg/kg of rFVIIa on coagulation parameters when applied to the blood drawn from patients undergoing OLT. Coagulation function was assessed in 10 patients at four points during OLT. These time points were baseline, 5 minutes prior to reperfusion, 10 minutes after reperfusion, and 70 minutes after reperfusion. These patients did not receive rFVIIa perioperatively. At each of these four time points, a native sample was analyzed for prothrombin time (PT) and thromboelastogram. The rFVIIa (6.1 microg/kg or the approximate equivalent dose of 120 microg/kg for a 70 kg patient) was added to a second sample from the same patient. This second sample was also analyzed for PT and thromboelastogram. There was a statistically significant difference in baseline PT between native versus rFVIIa supplemented samples (15.8 +/- 3.21 vs 13.6 +/- 2.36 seconds, P < .02). The maximum amplitude of the thromboelastogram was larger in the native samples at 5 minutes prior to reperfusion (53.5 mm vs 39 mm, P < .02). No significant differences existed in the variables at any of the other sampling times. This study failed to demonstrate a consistent in vitro effect of rFVIIa on the blood taken from patients during OLT.     

肝硬化大鼠行肝大部切除术后入肝血流对肝功能以及肝脏再生的影响

摘 要] 目的 研究肝硬化大鼠行肝大部切除术后入肝血流对肝功能以及肝脏再生的影响。方法 通过连续8周腹腔注射CCl4构建大鼠肝硬化模型,并在此基础上行肝大部切除术,分别缩窄门静脉和（或）肝动脉,建立不同流量的入肝血流模型,分成对照组、门静脉低流量+肝动脉高流量组、门静脉低流量+肝动脉低流量组、门静脉高流量+肝动脉高流量组、门静脉高流量+肝动脉低流量组,每组7 只大鼠。检测不同时间点大鼠肝功能指标的变化、肝脏组织的病理变化,采用免疫组化方法检测各组肝细胞中Ki-67 蛋白的表达,并对残余肝脏重量进行对比,判断不同状态的入肝血流对肝脏再生的影响。结果 肝大部切除+入肝血流调整后,门静脉低流量组肝细胞间充血减轻,细胞损伤明显减轻;门静脉低流量+肝动脉高流量组大鼠术后第1、3、5天血清ALT分别为（460.9±31.7）U/L、（ 331.0±22.0）U/L和（285.6±15.8）U/L;同时间点TBIL分别为（20.4±1.5）μmol/L、（ 16.1±1.0）μmol/L和（13.5±0.6）μmol/L;与对照组比较,均差异明显（P < 0.05）。术后第5 天,门静脉低流量+肝动脉高流量组、门静脉低流量+肝动脉低流量组及门静脉高流量+肝动脉高流量组大鼠肝细胞中Ki-67表达显著增强[分别为（23.9±3.6）%、（ 15.7±2.3）%、（12.9±2.4）%],与对照组（10.1±2.1）%相比差异明显（P < 0.05）,而门静脉高流量+肝动脉低流量组Ki-67表达阳性率（6.1±1.4）%明显低于对照组（P < 0.05）。门静脉低流量+肝动脉高流量组术后第5 天残余肝脏重量为（15.4±1.0）g,与对照组（11.8±0.7）g相比差异明显（P < 0.05）。结论 肝硬化大鼠行肝大部切除术后,降低门静脉血流量有助于减轻肝组织的充血,改善肝功能指标;肝细胞再生指标Ki-67 表达显著增加,残余肝脏重量明显增加。     

Role of NF-kappaB as effector of IPC in donor livers before liver transplantation in rats

The objective of this study was to investigate the effect of ischemic preconditioning (IPC) on NF-kappaB activity during reperfusion early after liver transplantation in rats. METHODS: Male Sprague-Dawley (SD) rats were used as donors and recipients of orthotopic liver transplantations. The donor liver was stored 2 hours in Ringer's solution at 4 degrees C preimplantation. IPC was performed by clamping of the portal vein and hepatic artery of the donor for 10 minutes followed by reperfusion for 10 minutes before harvesting. At 1, 2, 4, and 6 hours after portal vein reperfusion, graft samples were obtained to determine hepatic levels of NF-kappaB activity, tumor necrosis factor (TNF)-alpha and intercellular adhesion molecule (ICAM)-1. Blood samples were obtained to measure serum alanine aminotransferase (ALT) and lactate dehydrogenase (LDH). RESULTS: After liver transplantation without IPC, serum levels of ALT and LDH increased significantly compared with the sham-operated group. Among the IPC group, serum ALT and LDH decreased significantly. NF-kappaB activity in the graft increased within 6 hours after transplantation. Among the IPC group, NF-kappaB activity was significantly attenuated. Hepatic levels of TNF-alpha and ICAM-1 were significantly elevated in the non-IP group but both were reduced in the IPC group. CONCLUSION: IPC downregulated TNF-alpha and ICAM-1 expression in the graft, most likely through decreased NF-kappaB activation, and attenuated neutrophil infiltration after reperfusion.     

The liver protective effect of ischemic preconditioning may be mediated by adenosine

Abstract We investigated the involvement of adenosine in ischemic preconditioning (IPC) by the unspecific antagonist, 8‐phenyltheophylline (8‐PT). Anesthetized Wistar rats were treated as follows: 1. nonischemic controls, 2. ischemic controls: 60 min of clamping of the common hepatic artery followed by 60 min reperfusion, 3. IPC: 10 min ischemia followed by 15 min reperfusion, prior to the identical ischemia‐reperfusion (IR) period as in group 2, 4. 8‐PT + IPC: 8‐PT 10 mg/kg i. v. was given 10 min prior to the identical procedure as in group 3. The peripheral liver blood flow was monitored by laser‐Doppler flowmetry. Blood alanine aminotransferase (ALT) was analyzed once every 60 min. IPC significantly reduced impairment of liver blood flow, as well as ALT increase during reperfusion. This effect was abolished by pretreatment with 8‐PT. Adenosine appears to be a crucial effector in IPC. Clinical studies need to be undertaken to explore a possible effect of IPC in liver transplantation.     

c-Jun N-terminal kinase mediates hepatic injury after rat liver transplantation

BACKGROUND: Orthotopic liver transplantation (OLT) requires cold ischemic storage followed by warm reperfusion. Although c-Jun N-terminal kinase (JNK) is rapidly activated after OLT, the functional consequences of JNK activation are unknown. The aim of this study was to address the role of JNK after OLT using the selective JNK inhibitor CC-401. METHODS: Donors, recipients, or stored liver explants were treated with vehicle or JNK inhibitor before OLT by an arterialized two-cuff method with 40 hours of cold storage. Recipients were assessed for 30-day survival, and graft injury was assessed over time by hepatic histology, serum transaminases, caspase 3 activation, cytosolic cytochrome c, and lipid peroxidation. RESULTS: Survival after OLT increased after donor plus storage and storage only treatment with JNK inhibitor (P<0.05). Treatment of recipient only did not improve survival. Increased survival correlated with improved hepatic histology and serum aspartate aminotransferase levels. JNK inhibition significantly decreased nonparenchymal cell killing at 60 minutes after reperfusion (P<0.05) and pericentral necrosis at 8 hours after reperfusion (P<0.01). JNK inhibition decreased cytochrome c release, caspase 3 activation (P<0.05), and lipid peroxidation (P<0.05). JNK inhibition also transiently blocked phosphorylation of c-Jun at 60 minutes after reperfusion (P<0.05) without affecting other MAPK signaling, including p-38 and Erk activation. CONCLUSIONS: JNK inhibition decreases hepatic necrosis and apoptosis after OLT, suggesting that JNK activation promotes cell death by both pathways. Inhibition of JNK may be a new therapeutic strategy to prevent liver injury after transplantation.     

Impact of Hepatic Arterial Reconstruction on Orthotopic Liver Transplantation in the Rat

ABSTRACT

Orthotopic liver transplantation (OLT) models in rats have been investigated in many studies, but detailed information on the impact of hepatic artery (HA) reconstruction on postoperative factors remains to be investigated. HA reconstruction also requires advanced skills. The effect of the reconstruction of the HA by a hand-suture technique in rats with a whole-liver syngeneic graft was investigated. Long-term survival, histopathological assessment, immunohistological evaluation, and blood biochemistry were investigated until postoperative day (POD) 28. From the early postoperative period, significant differences between OLTs with or without HA reconstruction were found in graft parenchymal damage, induction of apoptosis, and transaminase levels, though survival curves and the coagulation profile showed no differences. In OLT without HA reconstruction, biliary proliferation was decreased at POD 5–14, and total bilirubin level was increased at PODs 10 and 14. The study indicates that HA reconstruction is required for reliable OLT in rats.