Comparison of HTK- and UW-solution for liver preservation tested in an orthotopic liver transplantation model in the pig

The aim of this experimental study was to compare the preservation potency of University of Wisconsin (UW) and HTK (Bretschneider) solutions in an orthotopic liver transplantation (OLT) model in pigs. Livers were harvested using an in situ perfusion technique, where organs were flushed with the solution being tested, stored on ice — cold storage (CS) — for 2 or 24 h and then transplanted. Parameters monitored were liver enzymes in serum, hepatic water content, high energy phosphates, nuclear magnetic resonance (NMR) relaxation time T2, light microscopy and bile production. CS for 24 h is an extreme in pig liver preservation and is not compatible with animal survival. Biopsies showed drastic morphological changes and grafts did not produce bile in either group. (Bile production 2 h CS: HTK, 5.6 ± 1.8 ml/h; UW, 4.7 ± 2.3 ml/h) Enzyme release after reperfusion (ASGOT, ?LDH) was higher in long-term preservation. Hepatic tissue water content significantly decreased during CS in UW preserved livers. Edema alter reperfusion (?H₂0: HTK 24 h = + 5.6%, UW 24 h= + 4.8%) and regeneration capacity after reperfusion (UW 2 h = 63%, HTK 2 h = 55%, UW 24 h = 30%, HTK 24 h = 30%) were not significantly different. However, we did not observe major differences in preservation potency between the solutions tested. Differences were correlated, rather, with length 9 time of CS, than with the solution used. Therefore, HTK solution seemed to be a low potassium containing alternative to UW solution.     

Preservation of the canine liver for 24-48 hours using simple cold storage with UW solution

The results of a series of 29 orthotopic liver transplants in the dog are described. The livers were preserved in a new cold storage fluid, UW solution, and were successfully transplanted after periods of storage of 24, 30, 36, and 48 hr. All six animals transplanted after 24 hr survived beyond 5 days after transplantation and had excellent graft function. Four of six survived for at least 5 days after 30 hr of cold storage, and five of five after 36 hr. Five of six consecutive dogs that received transplants that had been cold-stored for 48 hr survived for 5 or more days. This solution represents a substantial advance over all existing cold storage solutions for liver preservation.     

Comparison of Celsior and University of Wisconsin solutions in cold preservation of liver from octogenarian donors

BACKGROUND: Celsior (CS) has recently been proposed as a cold storage solution for thoracic and abdominal organs. We compared University of Wisconsin (UW) and CS solutions for the preservation of livers from old donors, with regard to initial function as well as short- and long-term graft and patient survival. METHODS: A multicenter retrospective study from 1998 to 2002 includes 30 livers from octogenarian donors preserved in CS (n = 15) or UW (n = 15) solution prior to transplantation. Donor and recipient clinical and laboratory parameters as well as liver biopsy results were evaluated in all cases. RESULTS: The distribution of the main donor variables as well as recipient characteristics were comparable between groups. Mean cold ischemia time was 421 minutes in the CS group and 474 minutes in the UW group. Mild steatosis was present in 8 cases in the CS group and 7 cases in the UW group. No primary graft dysfunction or arterial or biliary complications were noted. There was 1 acute rejection episode in the CS group and 4 in the UW group. Late postoperative deaths were observed only in the UW group (ie, 7 of 15). Actuarial graft survival was 100% in the CS group vs 86.7% in the UW group (P = NS) at 3 months, and 100% in the CS group vs 52.5% in the UW group (P =.007) at 12 months. Patient survival was 100% in the CS group vs 93.3% in the UW group (P = NS) at 3 months, and 100% in the CS group vs 59.3% in the UW group (P =.01) at 12 months. CONCLUSIONS: Both CS and UW solutions effectively protect livers obtained from donors >80 years of age during the early postoperative course but the CS group had better long-term results.     

Comparison of UW solution and Euro-Collins solutions for cold preservation of human liver grafts

University of Wisconsin solution, a new organ preservation medium, is reported to extend the period of cold storage. In order to evaluate the efficacy of UW solution in human liver preservation we compared 58 donor liver grafts preserved in Euro-Collins (EC) solution. All livers were harvested in a similar manner. Donor and recipient characteristics in the two groups were comparable. The mean preservation time of the UW solution was 11.5 +/- 4.2 hr (range 3-20 hr), significantly longer than the EC mean preservation time of 4.9 +/- 1.6 hr (2-9.6 hr) (P = 0.0001). Evaluation of mean postoperative liver function tests and coagulation factors on days 1-7 showed no statistical difference between the two groups. There was one primary graft nonfunction in the EC group and none with the UW organs. Hepatic artery thrombosis was similar in each group. The incidence of early retransplantation was similar. Three-month graft survival was 81% in the UW group vs. 73% in the EC group. Patient survival at three months was 87% with the UW organs and 84% with the EC organs. We conclude that cold storage of liver grafts in the UW solution has allowed for significantly longer preservation, permitting transplantation to be performed under semielective conditions and procurement of organs from much further distances. Grafts stored in UW solution perform as well as those stored in Euro-Collins, with no significant difference in liver function abnormalities postoperatively.     

Celsior液与UW液对无心跳大鼠供肝保存效果的比较

目的 比较Celsior(CS)液与UW液对大鼠无心跳供者(NHBD)供肝的保存效果.方法 选取健康雄性SD大鼠作为肝移植的供、受者.通过阻断大鼠主动脉和膈上下腔静脉10 min的方法,制备和获取NHBD供肝,并采用不同的器官保存液灌注和冷保存供肝.随机将受者分为4组.CS8 h组:受者采用经CS液灌注和冷保存8 h的供肝移植;UW8 h组:受者采用经UW液灌注和冷保存8 h的供肝移植;CS16 h组:受者采用经CS液灌注和冷保存16 h的供肝移植;UW16 h组:受者采用经UW液灌注和冷保存16 h的供肝移植.受者门静脉开放前、开放后1、3及6 h,取各组受者的静脉血检测血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、内皮素1(ET-1)、白细胞介素1(IL-1)及肿瘤坏死因子α(TNF-α)水平;观察和比较各组受者的胆汁生成量、移植肝组织病理学改变及术后7 d内的存活率.结果 NHBD供肝经UW液灌注后呈"花斑"状,肝叶边缘灌注不良,经CS液灌注后肝叶边缘灌注良好.CS8 h组和UW8 h组受者的胆汁生成量分别为(0.21±0.01)ml和(0.10±0.02)ml(P<0.05).门静脉开放后1、3及6 h,CS8 h组受者的血清ALT及AST水平明显低于UW8 h组(P<0.05),门静脉开放后1、3h,CS8 h组受者的血清ET-1、IL-1及TNF-α水平均明显低于UW8 h组(P<0.05);CS8 h组受者移植肝肝窦扩张、门静脉充血及炎症细胞浸润等病理学改变明显轻于UW8 h组,CS8 h组和UW8 h组受者术后7 d的存活率分别为58.3%和25.0%(P<0.05).CS16 h组和UW16 h组受者各时点的胆汁分泌量、血清ALT、AST、ET-1、IL-1及TNF-α水平的比较,差异均无统计学意义(P>0.05),两组受者均在术后3 d内死亡,两组受者移植肝组织病理学改变无明显差异.结论 CS液对大鼠NHBD供肝的保存效果优于UW液,这可能与UW液较CS液粘稠及CS液能够减少枯否细胞的激活有关;NHBD供肝的冷保存时间不宜超过16 h.     

Extended preservation and effect of nitric oxide production in liver transplantation

Abstract Liver transplantation (Ltx) has become a routine procedure for patients with enD-stage liver disease. Despite ongoing progress on short- and long-term graft survival, primary dysfunction (PDF) remains a major problem. PDF is significantly associated with the duration of cold ischemia- and, possibly, with reperfusion-related injury. Nitric oxide (NO) has many physiological functions and plays an important role in modulating tissue injury. However, the mechanism of NO action in ischemia/reperfusion injury after Ltx is thus far unknown. In this study we investigated the role of inducable NO synthase (iNOS) in the liver after preservation with UW solution using the orthotopic Ltx model in the rat. Male Brown Norway rats were used for the Ltx procedure. After donor hepatectomy, livers were stored on ice-cold UW solution for 24 or 40 h and subsequently transplanted. A control group consisted of rats with Ltx after less than 1 h storage. Post-transplant blood samples were taken at 48 h to determine standard parameters for liver injury (aspartate transaminase, lactate dehydrogenase). Liver biopsies were obtained for detection of expression of iNOS (western blot) 24 and 48 h post-transplant. We observed that a preservation time of 24 h in UW solution presents no problem for graft survival after Ltx in rats with some brain function and in healthy animals. After 40 h preservation, liver damage is obvious and graft survival reduced, indicating the limits of cold storage may be within reach. With longer preservation times, more NOs was detected in liver tissue. This finding suggests that NO has a role in ischemia/reperfusion-related injury. Current intervention with NOS inhibitors will reveal whether NO has a negative or a positive effect on graft survival after Ltx.     

Clinical application of the two-layer (University of Wisconsin solution/perfluorochemical plus O2) method of pancreas preservation before transplantation

BACKGROUND: The two-layer method [University of Wisconson solution (UW)/perfluorochemical plus O2] for pancreas preservation has been demonstrated to be superior to simple UW storage alone in the canine model. For the first time, we applied the two-layer method to clinical whole-pancreas transplantation. METHODS: Pancreases were placed in the two-layer method in 10 cases and UW alone in 44 cases before transplant. The mean cold ischemic time was 16.5 hr in the two-layer group versus 18.1 hr in the UW group (P=NS). We compared the condition of graft at the time of reperfusion, and then 3 months posttransplant graft function and complications. RESULTS: At the time of reperfusion, no grafts in the two-layer group were edematous, compared with 10(23.3%) of 43 in the UW group (P=0.18). Seven (70%) of 10 grafts in the two-layer group obtained the best overall quality score, compared with 24(57.1%) of 42 in the UW group (P=0.72). Nine (90%) of 10 recipients in the two-layer group became insulin-independent during hospitalization, compared with 31(70.5%) of 44 in the UW group (P=0.26). Time to insulin independence was no different between the two groups. No pancreas grafts preserved by the two-layer method suffered acute rejection. Conclusions. The two-layer preservation method is feasible in human clinical transplantation. It was at least equivalent and may be superior to UW alone in both morphologic and functional assessment of the transplanted pancreas.     

A comparison of Collins and UW solutions for cold ischemic preservation of the rat liver

A new solution which can extend successful preservation times for hepatic allografts was recently developed at the University of Wisconsin (UW). To examine the mechanism of improved viability using this solution, we developed a model of orthotopic hepatic transplantation in the rat. As a baseline study, we compared parameters of viability of allografts preserved in Collins solution to those preserved in UW, including survival, bile output, peak AST, and allograft weight change during storage. Seventy-four rats were transplanted following storage in Collins solution and 70 rats were transplanted after storage in UW. Cold-storage time varied between 2 and 24 hr. The survival with preservation in UW was significantly better than that with Collins when storage time was greater than 2 hr. The preservation time for a viable organ using UW was greater than double that using Collins. The peak AST using UW was lower than that with Collins for cold ischemic times (CIT) up to 10 hr, with significance demonstrated at 5-6 and 7-8 hr when compared with Collins. Prolonged CIT resulted in an increase in liver weight with Collins-preserved livers and a decrease in weight with UW-preserved livers. Using a model of orthotopic liver transplantation in the rat, we demonstrated a doubling of preservation time when UW solution was substituted for Collins. Similar improvements in recipient survival and biochemical parameters of injury have been demonstrated in the canine model and in human clinical trials.     

Donor brain death reduces survival after transplantation in rat livers preserved for 20 hr.

BACKGROUND: Eighty percent of donor organs come from donors who have suffered brain trauma (brain-dead donors). This unphysiological state alters the hemodynamic and hormonal status of the organ donor. This can cause organ injury, which has been suggested to alter the immunological or inflammatory status of the organ after transplantation, and may lead to increased sensitivity of the organ to preservation/transplantation injury. In this study we asked the question: does brain death cause injury to the liver that decreases successful liver preservation? METHODS: The rat liver transplant model was used to compare survival in rats receiving a liver from a brain-dead donor versus a non-brain-dead donor. Brain death was induced by inflation of a cranially placed balloon catheter. The rats were maintained normotensive with fluid infusion for 6 hr. The livers were flushed with University of Wisconsin (UW) solution and immediately transplanted or cold stored for 20 hr before transplantation. RESULTS: Recipient survival with immediately transplanted livers or those stored for 20 hr was 100% with livers from non-brain-dead donors. However, survival decreased when livers were procured from brain-dead donors. Survival was 75% (6/8) when storage time was 0 hr and 20% (2/10) when the liver was cold stored for 20 hr before transplantation. CONCLUSION: This study shows that brain death induces alterations in the donor liver that make it more sensitive to preservation/reperfusion injury than livers from donors without brain death. The mechanism of injury to the liver caused by brain death is not known. Because most livers used clinically for transplantation come from brain-dead donors, it is possible that poor function of these livers is due to the intrinsic condition of the donor organ, more than the quality of the preservation. Methods to treat the brain-dead donor to improve the quality of the liver may be needed to allow better preservation of the organ and to give better outcome after liver transplantation.     

Viability of liver grafts from fasted donor rats: relationship to sinusoidal endothelial cell apoptosis

Previous studies have shown that livers from fasted donors appear to tolerate long-term preservation better than livers from fed donors, but the mechanism is not clear. Some studies have shown that the apoptosis of sinusoidal endothelial cells (SEC) appeared to be a pivotal mechanism of ischemia/reperfusion injury in liver transplantation. The purpose of the present investigation was to evaluate the relation of SEC apoptosis to liver viability in rats after liver transplantation, comparing findings for fasted and fed donors. Wistar rats were used as donors and recipients. The fed group had access to solid feed and water ad libitum. The fasted group was allowed access only to water for 4 days prior to liver harvest. All rat livers were preserved with University of Wisconsin (UW) solution at 2 °C for 24 h. After preservation, the livers were orthotopically transplanted, and survival time was measured. Apoptosis was determined by in-situ staining for apoptotic cells, using a TdT-mediated dUTP-digoxigenin nick-end labeling (TUNEL) assay and electron microscope (EM) examination separately. The 14-day survival rates after 24-h preservation were 0% (0/11) for recipients of livers from fed donors and 91% (10/11) for recipients of livers from fasted donors. There was no significant difference in the numbers of TUNEL-positive SEC after 24-h preservation between the two groups. However, at 6 h after transplantation, the number of TUNEL-positive SEC was significantly higher in the fed group than in the fasted group. These results suggest that donor fasting decreases SEC apoptosis after reperfusion alone, and that this may be related to the protection of the liver graft from reperfusion injury. Received: December 22, 2000 / Accepted: February 15, 2001     

A multicenter pilot prospective study comparing Celsior and University of Wisconsin preserving solutions for use in liver transplantation

Primary dysfunction (PDF) still occurs after orthotopic liver transplantation (OLT). Celsior solution (CS) might offer some advantages over the conventional University of Wisconsin (UW) solution for organ preservation, but to date, this has not been prospectively evaluated in the context of OLT. In this prospective, randomized, multicenter, pilot study, 215 potential liver donors were enrolled and randomized. In 42 cases, the livers were unsuitable for transplantation; therefore, 173 randomized livers ultimately were implanted after perfusion and cold preservation with CS (n = 83) or UW solution (n = 90). In accord with the indications of the CS manufacturing company, total CS infusion volume was 90 mL/kg, greater than that of UW solution (60 mL/kg). The main aim of the study is to compare the prevalence of PDF between the two groups. Donor and recipient variables were similar in the two groups. Episodes of PDF were numerically lower in the CS (2.4%) than UW group (7.8%), but the difference was not statistically significant. There was a trend toward a lesser need for early re-OLT (<30 days) in the CS group (P = .0507), but again, no statistically significant difference emerged. Overall and time-differentiated postoperative deaths also were similar. One-year actuarial patient (UW, 89% v CS, 87%) and graft (UW, 83% v CS, 85%) survival rates were similar. In conclusion, CS was similar to UW solution as a preservation solution in the clinical setting of OLT at the infusion volumes described, although some theoretical advantages of CS composition suggest that CS might prove a valid alternative to UW preservation solution in multiorgan harvesting, including the liver. A study on a larger patient basis is needed. (Liver Transpl 2003;9:814-821.)     

大鼠肝脏保存中不同器官保存液对肝细胞凋亡的影响

目的 研究３种目前国内常用的器官保存液对供肝细胞凋亡的影响。方法 分别用ＵＷ液、ＨＣ－Ａ液和ＷＭＯ－１号液灌洗并保存大鼠肝脏,于保存后０、１２、２４ｈ用原位末端标记法检测供肝细胞凋亡情况,并将保存２４ｈ的肝及行大鼠原位全肝移植,观察受者的３ｄ存活率。结果 ３种保存液保存的肝脏均在保存１２ｈ时出现细胞凋亡,ＨＣ－Ａ液级瑟ＷＭＯ－１号液组的凋亡指数（ＡＩ）高于ＵＷ液组（Ｐ〈０．００１）,而ＨＣ－Ａ液组     

Sequential cold storage and normothermic perfusion of the ischemic rat liver

Extending transplant criteria to include livers obtained from donors after cardiac death (DCD) could increase the liver donor pool, but conventional simple cold storage of these ischemic organs can lead to poor graft function after transplantation. Experimental normothermic machine perfusion has previously proven to be useful for the recovery and preservation of DCD livers, but it is more complicated than conventional cold storage, and, therefore, is perhaps not practical during the entire preservation period. In clinical situations, the combined use of simple cold storage and normothermic perfusion preservation of DCD livers might be more realistic, but even a brief period of cold storage prior to normothermic preservation has been suggested to have a negative impact on graft viability. In this study we show that rat livers subjected to 45 minutes of ex vivo warm ischemia followed by 2 hours of simple cold storage can be reclaimed by 4 hours of normothermic machine perfusion. These livers could be orthotopically transplanted into syngeneic recipients with 100% survival after 4 weeks (N = 10), similar to the survival of animals that received fresh livers that were stored on ice in University of Wisconsin (UW) solution for 6 hours (N = 6). On the other hand, rats that received ischemic livers preserved on ice in UW solution for 6 hours (N = 6) all died within 12 hours after transplantation. These results suggest that normothermic perfusion can be used to reclaim DCD livers subjected to an additional period of cold ischemia during hypothermic storage.     

Advantages of normothermic perfusion over cold storage in liver preservation

BACKGROUND: To minimize the ischemia-reperfusion injury that occurs to the liver with the current method of preservation and transplantation, we have used an extracorporeal circuit to preserve the liver with normothermic, oxygenated, sanguineous perfusion. In this study, we directly compared preservation by the standard method of simple cold storage in University of Wisconsin (UW) solution with preservation by perfusion. METHODS: Porcine livers were harvested from large white sows weighing between 30 and 50 kg by the standard procedure for human retrieval. The livers were preserved for 24 hr by either cold storage in UW solution (n=5) or by perfusion with oxygenated autologous blood at body temperature (n=5). The extracorporeal circuit used included a centrifugal pump, heat exchanger, and oxygenator. Both groups were then tested on the circuit for a 24 hr reperfusion phase, analyzing synthetic function, metabolic capacity, hemodynamics, markers of hepatocyte and reperfusion injury, and histology. RESULTS: Livers preserved with normothermic perfusion were significantly superior (P=0.05) to cold-stored livers in terms of bile production, factor V production, glucose metabolism, and galactose clearance. Cold-stored livers showed significantly higher levels of hepatocellular enzymes in the perfusate and were found to have significantly more damage by a blinded histological scoring system. CONCLUSIONS: Normothermic sanguineous oxygenated perfusion is a superior method of preservation compared with simple cold storage in UW solution. In addition, perfusion allows the possibility to assess viability of the graft before transplantation.     

Pancreas preservation with University of Wisconsin and Celsior solutions: a single-center, prospective, randomized pilot study

BACKGROUND: Celsior is an extracellular-type, low-viscosity, preservation solution already used for heart, lung, liver, and kidney transplantation. We report the results of a single-center, prospective, randomized pilot study specifically designed to compare the safety profile of Celsior solution with University of Wisconsin (UW) solution in clinical pancreas transplantation. METHODS: A total of 105 consecutive procurements were randomized to graft preservation with UW (n=53) solution or Celsior (n=52) solution. The groups were comparable with regard to all donor and recipient characteristics. RESULTS: Five grafts were discarded and 100 grafts (50 UW vs. 50 Celsior) were transplanted. Mean cold and warm ischemia times were 11.0 +/- 2.1 hr and 37.2 +/- 6.0 min for UW compared with 10.8 +/- 1.8 hr and 38.1 +/- 5.9 min for Celsior (P =not significant). Delayed endocrine pancreas function was recorded in one graft preserved with UW solution. Eleven recipients (UW 12% vs. Celsior 10%, P =not significant) required a relaparotomy. The mean serum levels of glucose, amylase, and lipase remained comparable between the study arms at equivalent intervals after transplantation. One recipient died with functioning grafts in each study arm; two further grafts were lost to arterial thrombosis (Celsior) and chronic rejection (UW), respectively. Actuarial 1-year patient and graft survival rates overlapped in the two study arms (98% and 96%, respectively). CONCLUSIONS: Within the range of cold ischemia time reported in this study, UW and Celsior solutions have similar safety profiles for pancreas preservation.     

Correlation of donor nutritional status with sinusoidal lining cell viability and liver function in the rat

We have demonstrated that the sinusoidal lining cell injury sustained by rat liver allografts during hypothermic storage is a critical determinant of graft viability. The present study was designed to examine the effect of donor nutritional status on hepatic microcirculation and graft function. Rat livers from four nutritional groups (group I, fasted; group II, fed; group III, intraperitoneal glucose; and group IV, fed plus intraperitoneal glucose) were excised and stored for 24 hr in Marshall's isotonic citrate solution. Then the livers were perfused under anoxic conditions with trypan blue. The percentage of nonviable SLC in each group was 26.7 +/- 8.1, 24.9 +/- 7.9, 17.6 +/- 6.9, and 5.9 +/- 1.9 in groups I, II, III, and IV respectively; i.e., there was a significant improvement in SLC viability with nutritional repletion in group IV. Electron microscopy was performed on livers from groups I and IV following 30-hr preservation in University of Wisconsin solution and after 16-hr preservation in Marshall's isotonic citrate solution. Biopsies were taken at the end of storage and after 1 hr of reperfusion at 37 degrees C. At the end of preservation group IV livers contained glycogen and had much more normal liver ultrastructure than group I livers. After reperfusion there was partial recovery of normal SLC morphology in both groups and depletion of glycogen in group IV. Liver function was studied on the isolated perfused rat liver system at 37 degrees C following 30-hr storage in UW solution. Transaminase release into the perfusate was significantly lower in nutritionally repleted livers than in livers from fasted animals. A significant reduction in perfusate platelet count occurred only in livers from fasted animals. The results show that nutritional repletion can reduce the injury of cold preservation to both hepatocytes and endothelial cells and improve liver function in the postpreservation period.     

Apoptosis and regeneration of sinusoidal endothelial cells after extended cold preservation and transplantation of rat liver

BACKGROUND: Sinusoidal endothelial cells (SECs) are particularly susceptible to cold ischemia-reperfusion (I/R) injury. We have examined the process of injury and recovery of graft after cold-preserved liver transplantation, with special focus on the proliferation of SECs and regulatory mechanisms involved. METHODS: Male SD rats were divided into two groups according to length of cold preservation time in University of Wisconsin [UW] solution of graft: UW1h group and UW12h group. Graft function, incidence of apoptosis, proliferation of SECs and the expression of related regulatory factors were assessed after orthotopic liver transplantation (OLT). RESULTS: SECs are more sensitive to apoptosis induced by cold I/R injury compared with hepatocytes. Using bromodeoxyuridine and rat endothelial cell antigen-1 double immunostaining assay, SECs exhibited a delayed proliferation in comparison with hepatocytes, reaching a peak at 72 hr in UW1h group and 96 hr in UW12h group, respectively. Vascular endothelial growth factor increased at 24 hr after reperfusion, and peaked at 72 hr in both groups. Flt-1 and flk-1 expression was found to be mainly limited to SECs, with a peak in expression occurring between 72 and 96 hr, which coincided with the peak in SEC proliferation in UW1h group. However, flt-1 was found to be reduced significantly at any time throughout the experiments in UW12h group compared to sham. CONCLUSION: The delayed recovery of rat liver after extended cold preservation and transplantation correlates with a retarded regeneration of SECs due to increased apoptosis and reduced expression of flt-1. These results suggest that SECs play an important role in cold-preserved liver transplantation.     

The effects of fasting on the quality of liver preservation by simple cold storage

Although livers can be successfully preserved for 24 hr or more, often the transplanted livers have poor or no (primary nonfunction) function. The quality of the liver does not appear dependent upon the time of preservation but may be dependent upon the condition of the donor. In this study we have investigated the effects of fasting on the quality of livers for transplantation. Rabbits were fasted (48 hr) and livers preserved in the UW solution for 6-8 hr. Functions of the liver were analyzed by isolated perfusion for 2 hr. Also, pigs were fasted for 72 hr, livers preserved for 12 hr, and viability determined by orthotopic transplantation. Fasting depleted the liver glycogen by 85% but had no effect on ATP or glutathione concentrations. Rabbit livers from fasted animals produced similar amounts of bile, released similar concentrations of lactate dehydrogenase (LDH) and aspartate amino transaminase (AST) into the perfusate, maintained similar concentrations of ATP and glutathione in the tissue, and had a similar intracellular K:Na ratio after 24-hr preservation when compared to livers from fed animals. After 48-hr preservation, livers from fasted animals were less viable than livers from fed animals, including: reduced bile production (2.0 +/- 0.3 vs. 5.0 +/- 0.9 ml/2 hr, 100 g), greater release of LDH (3701 +/- 562 units vs. 1123 +/- 98 units) and AST, less ATP (0.326 +/- 74 vs. 0.802 +/- 160 nmol/g), less glutathione (0.303 +/- 13 vs. 0.933 +/- 137 nmol/g), and a lower K:Na ratio (1.5 +/- 0.9 vs. 7.4 +/- 0.6). Pigs receiving livers from fed animals preserved for 12 hr had better survival (5/6, 83%) than livers from fasted animals (3/6, 50%). The results show that the nutritional status of the donor can affect the outcome of liver preservation and transplantation. Increased injury in livers from fasted animals may be due to the loss of glycogen that may be an essential source of energy in the initial posttransplant period. In clinical liver transplantation the nutritional status of the donor may be an important factor in the initial function of the liver, and methods to increase the nutritional status of the donor may be important in increasing the quality of livers.     

Delivery of the bioactive gas hydrogen sulfide during cold preservation of rat liver: effects on hepatic function in an ex vivo model

The insults sustained by transplanted livers (hepatectomy, hypothermic preservation, and normothermic reperfusion) could compromise hepatic function. Hydrogen sulfide (H₂S) is a physiologic gaseous signaling molecule, like nitric oxide (NO) and carbon monoxide (CO). We examined the effect of diallyl disulfide as a H₂S donor during hypothermic preservation and reperfusion on intrahepatic resistance (IVR), lactate dehydrogenase (LDH) release, bile production, oxygen consumption, bromosulfophthalein (BSP) depuration and histology in an isolated perfused rat liver model (IPRL), after 48 h of hypothermic storage (4°C) in University of Wisconsin solution (UW, Viaspan). Livers were retrieved from male Wistar rats. Three experimental groups were analyzed: Control group (CON): IPRL was performed after surgery; UW: IPRL was performed in livers preserved (48 h—4°C) in UW; and UWS: IPRL was performed in livers preserved (48 h—4°C) in UW in the presence of 3.4 mM diallyl disulfide. Hypothermic preservation injuries were manifested at reperfusion by a slight increment in IHR and LDH release compared with the control group. Also, bile production for the control group (1.32 µL/min/g of liver) seemed to be diminished after preservation by 73% in UW and 69% in UW H₂S group at the end of normothermic reperfusion. Liver samples analyzed by hematoxylin/eosin clearly showed the deleterious effect of cold storage process, partially reversed (dilated sinusoids and vacuolization attenuation) by the addition of a H₂S delivery compound to the preservation solution. Hepatic clearance (HC) of BSP was affected by cold storage of livers, but there were no noticeable differences between livers preserved with or without diallyl disulfide. Meanwhile, livers preserved in the presence of H₂S donor showed an enhanced capacity for BSP uptake (k_ACON = 0.29 min^?1; k_AUW = 0.29 min^?1; k_AUWS = 0.36 min^?1). In summary, our animal model suggests that hepatic hypothermic preservation for transplantation affects liver function and hepatic depuration of BSP, and implies that the inclusion of an H₂S donor during hypothermic preservation could improve standard methods of preparing livers for transplant.     

SWH液对大鼠肝脏保存中肝细胞凋亡的影响

目的　通过与UW液进行比较 ,观察SWH保存液对大鼠肝细胞凋亡及其对肝移植受者存活率的影响。方法　应用大鼠原位肝移植模型 ,通过HE染色、电镜和TUNEL法检测肝细胞凋亡以及观察移植术后 7d动物存活率。结果　随着保存时间的延长 ,两组的凋亡指数 (AI)均无明显升高 ,保存 18h后 ,两组的AI亦无明显改变 ,仅在行肝移植恢复血流循环后AI才明显上升 ,移植前后存在显著性差异 ,P <0 .0 1,SWH液组略低于UW液组 ;SWH液组移植术后 7d动物存活率有高于UW液组的趋势。结论　有效地防止肝细胞凋亡可以提高肝脏的保存效果 ,在防止肝细胞凋亡方面 ,SWH液优于UW液。