缺血预处理对大鼠胰腺移植缺血/再灌注损伤的保护机制

目的探讨缺血预处理对大鼠胰腺移植缺血/再灌注损伤的保护机制。方法建立SD大鼠糖尿病模型。取糖尿病大鼠24只,随机分为缺血/再灌注组(I/R组,n=6)和缺血预处理组(IPC组,n=18),IPC组又平均分为3个亚组:IPC1组(阻断脾血管5min,再灌注5min)、IPC2组[(阻断脾血管5min,再灌注5min)×2次]和IPC3组[(阻断脾血管5min,再灌注5min)×3次]。另取健康SD大鼠6只作为对照组,仅打开腹腔,不做胰腺移植;I/R组和IPC组大鼠均行同种胰腺移植。检测各组胰腺移植再灌注后2h后移植胰组织中超氧化物歧化酶(SOD)和髓过氧化物酶(MPO)的活性;用原位末端脱氧核糖核酸转移标记(TUNEL)法观察移植胰组织的细胞凋亡情况;WesternBlot法检测移植胰组织Bcl-2和Bax基因表达情况。结果IPC各组与I/R组相比较,前者移植胰组织中SOD活性明显升高,MPO活性明显降低,细胞凋亡指数明显降低,Bcl-2表达明显升高,Bax表达明显降低,各项检测指标比较,差异均有统计学意义(P<0.05)。IPC各组中又以IPC2组的各项检测指标差异更为显著(P<0.05)。结论缺血预处理可以减少移植胰缺血/再灌注后的细胞凋亡,IPC2组的效果更为突出。其机制可能与缺血预处理减轻嗜中性粒细胞(PMNs)粘附与聚集、减少氧自由基、上调Bcl-2基因和下调Bax基因的表达有关。     

Ischemic preconditioning fails to improve microcirculation but increases apoptotic cell death in experimental pancreas transplantation

Brief periods of warm ischemia and subsequent short reperfusion before either long-term cold or warm ischemic insult (ischemic preconditioning, IPC) have proven to ameliorate ischemia/reperfusion (I/R) injury in various organs, such as the liver and lung. The aim of this study was to examine the effect of IPC on pancreatic cell apoptosis and microcirculatory impairments in experimental pancreas transplantation. Male Lewis rats served as donors and recipients of heterotopic syngeneic pancreaticoduodenal transplantation. Recipient animals were divided into two experimental groups: group Tx (n=7) received grafts without IPC, group Tx&IPC received grafts with IPC. Animals that had not undergone transplantation but whose pancreata had been exteriorized served as controls (n=5). All pancreatic grafts were preserved in University of Wisconsin solution for 6 h at 4°C. IPC was induced by interruption of the arterial blood flow for 10 min followed by 10 min of reperfusion. One and two hours after reperfusion, graft microcirculation was assessed by means of intravital microscopy (IVM). Rats were immediately killed after the second measurement and DNA breaks of acinar cells were detected by in situ terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate digoxigenin nick end-labelling (TUNEL) assay and gel electrophoresis (laddering). The apoptotic index (AI) was defined as the number of apoptotic cells per high-power field. Analysis of both groups of transplanted grafts showed a significant decrease in functional capillary density (FCD) and a significant increase in leukocyte sticking to postcapillary venules (LAV) at 1 h and 2 h of reperfusion, compared with animals that had not undergone transplantation (P<0.01). In parallel, AI was significantly increased in transplanted grafts compared to the controls (P<0.01). Grafts subjected to IPC showed no significant differences, neither for FCD nor LAV, at both time points if compared with grafts of group Tx. However, IPC resulted in a significant increase in AI (P<0.05). We can conclude that IPC has no effect on pancreatic microcirculation but enhances acinar cell apoptosis in experimental pancreas transplantation. These results indicate that IPC might increase I/R injury after pancreatic cold ischemia.     

一氧化氮在犬离体胰腺低温灌注与保存中的作用

目的探讨一氧化氮(NO)对犬胰腺低温灌注及保存中缺血再灌注损伤的影响。方法在EC(EuroCollin)液中分别加用L精氨酸(LArg,200mg/kg体重)、N硝基L精氨酸甲酯(LNAME,10mg/kg体重)和生理盐水,分别对犬离体胰腺节段进行低温灌注保存(灌注量为30～50ml,温度为0～4℃,时间为24h),应用犬胰节段移植模型,测定移植后犬血清中脂肪酶、淀粉酶含量,测定移植胰腺组织中髓过氧化酶(MPO)活性、一氧化氮(NO)含量、一氧化氮合酶(NOS)及诱导型一氧化氮合酶(iNOS)mRNA的表达情况。并进行组织学观察。结果血清脂肪酶,LArg处理组<对照组对照组(0.31±0.06)μmol/L>LNAME处理组(0.17±0.04)μmol/L;NOS活性:LArg处理组(3.13±0.19)U/ml>对照组(2.37±0.20)U/ml>LNAME处理组(1.68±0.20)U/ml;iNOSmRNA的表达:LArg处理组(0.89±0.22)μmol/L>对照组(0.63±0.18)μmol/L>LNAME处理组(0.49±0.20)μmol/L,差异有统计学意义(P<0.05);LArg处理组胰小叶间质水肿和胰小叶内中性粒细胞浸润较轻。结论NO对犬胰腺低温灌注及保存中缺血再灌注损伤具有保护作用。     

Perfusion imaging of pancreas allografts using technetium-99m hexamethyl propylene amine oxime

The vascular integrity and major changes in perfusion can be determined by visual interpretation of radionuclide flow studies. We studied the potential of a new radiopharmaceutical technetium-99m hexamethyl propylene amine oxime (^99mTc-HMPAO) in the particular setting of pancreas transplantation. Perfusion was measured by perfusion indices (PI). Changes in graft perfusion were estimated by three independent observers. A predefined scale from 0 to 4 was used, with 0 representing no visualisation of the graft and 4 denoting sharp countour delineation and distinct demarcation from the background. In order to investigate the relation between perfusion of the pancreas graft and its exocrine function, we measured the amylase excretion rate (AER) in the urine, expressed in units per hour. It is concluded that ^99mTc-HMPAO is a suitable radiopharmaceutical for pancreas allograft imaging. For the assessment of the vascular integrity in the direct postoperative period, the scintigram is very reliable. Although a correlation between exocrine function of the graft and the perfusion score was not established, it is possible to make a clear sorting of AER measurements into different groups.     

参附注射液对大鼠移植胰缺血再灌注损伤的保护作用和机制

目的：探讨参附注射液对大鼠移植胰缺血再灌注损伤的保护作用及其机制。方法：正常SD大鼠为阴性对照组（NC组，n=6），糖尿病SD大鼠24只随机分为阳性对照组（PC组，n=6）、参附预处理组（SF组，n=6）、红参预处理组（HS组，n=6）和附子预处理组（FZ组，n=6）。除对照组外各组均行胰腺移植，24只SD大鼠为供体。SF、HS和FZ组在移植前1日及术前30min经静脉分别予受体注射参附注射液（10mg／kg）、红参注射液（9mg／kg）、附子注射液（1mg／kg），NC组和PC组在移植前1日及术前30min经静脉予受体注射同等容积生理盐水。检测各组再灌注前、后血糖；再灌注后2h血清中TNF-α和一氧化氮（NO）的含量、移植胰组织中超氧化物歧化酶（SOD）、髓过氧化物酶（MPO）和丙二醛（MDA）含量；用TUNEL法观察移植胰组织细胞凋亡情况，Western Blot法检测移植胰组织Bax和Bcl-2蛋白表达情况。结果：再灌注后SF组、HS组和FZ组较PC组血糖低，血清中TNF-α含量低，NO含量高：再灌注后SF组、HS组和FZ组较PC组移植胰组织中SOD活性高，MDA含量低，MPO活性低，凋亡指数低，Bcl-2表达高．Bax表达低，Bcl-2／Bax比值高。结论：参附注射液对大鼠移植胰的缺血再灌注损伤具有保护作用，机制可能是提高SOD的活性，增加内源性NO的合成，减少TNF-α分泌，减轻嗜中性粒细胞（PMNs）黏附与聚集，上调Bcl-2和下调Bax基因表达。     

IPC、IPO和IPC-IPO对胰腺冷缺血再灌注损伤保护作用的对比研究

目的对比研究缺血预处理(IPC)、缺血后处理(IPO)以及二者联合应用(IPC-IPO)对胰腺缺血再灌注损伤(IRI)的保护作用。方法建立SD大鼠糖尿病模型,24只糖尿病大鼠用于建立胰腺移植模型,随机分为4组,每组6只:I/R组、IPC组、IPO组和IPC-IPO组,另6只糖尿病SD大鼠为假手术组(SO组),检测各组大鼠再灌注前、后血糖水平以及再灌注后2 h移植胰腺组织中SOD和MDA含量,并采用TUNEL法观察移植胰腺组织细胞凋亡情况。结果各组大鼠再灌注前血糖水平之间的差异均无统计学意义(P>0.05);SO组大鼠再灌注后血糖水平明显高于其他4组(P<0.01);I/R组、IPC组、IPO组和IPC-IPO组大鼠再灌注后血糖水平均比再灌注前明显下降(P<0.05或P<0.01),I/R组又明显高于后3组(P<0.01),而后3组大鼠再灌注后血糖水平间的差异均无统计学意义(P>0.05)。再灌注后IPC组、IPO组和IPC-IPO组大鼠与I/R组比较MDA含量均明显降低(P<0.01),而SOD含量均明显升高(P<0.01);与SO组比较,I/R组、IPC组、IPO组和IPC-IPO组大鼠MDA均明显升高(P<0.01),而SOD含量均明显降低(P<0.01);IPC组、IPO组和IPC-IPO组大鼠MDA及SOD含量的差异无统计学意义(P>0.05)。I/R组、IPC组、IPO组和IPC-IPO组大鼠再灌注后2 h胰腺组织中AI值分别为(47.31±4.52)%、(26.25±3.17)%、(24.73±3.62)%和(25.5±4.15)%,均明显高于SO组的(3.16±0.53)%,P<0.01;IPC组、IPO组和IPC-IPO组大鼠与I/R组比较AI值明显降低(P<0.01);而IPC组、IPO组和IPC-IPO组间AI值的差异均无统计学意义(P>0.05)。病理组织学检查显示,I/R组大鼠胰腺损伤最为明显。结论 IPO和IPC对胰腺的IRI均有相似的保护作用。IPC与IPO联合应用对大鼠胰腺IRI和细胞凋亡的保护作用无叠加效应。     

Thymoglobulin induction protects liver allografts from ischemia/reperfusion injury

BACKGROUND: Interventions that minimize hepatic ischemia/reperfusion injury (IRI) can expand the donor organ pool. Thymoglobulin (TG) induction therapy has been shown to ameliorate delayed graft function and possibly decrease IRI in cadaver renal transplants recipients. This controlled randomized trial was designated to assess the ability of TG to protect against IRI in liver transplant recipients. PATIENTS AND METHODS: Twenty-two cadaveric liver transplant recipients were randomized to receive either TG (1.5 mg/kg/dose) during the anhepatic period and QOD x2 doses or no TG. No differences in recipients' demographics were present and donor characteristics were similar in terms of age, cause of death, and cold ischemia time. Maintenance immunosupression consisted of Tacrolimus (or Cyclosporine) and steroids for both groups. Donor biopsies were obtained during organ procurement, cold storage and 1 h after re-vascularization. Post-operative liver function tests were monitored. Early graft function, length of stay, patient and graft survival rates, incidence of primary non-function and rate of rejection were assessed. RESULTS: Patient and graft survival at 3 months was 100%. There was no incidence of primary graft non-function and no need for re-transplantation. The incidence of acute rejection was similar between the two groups. Patients in the TG group had significant decreases in alanine aminotransferase test at day 1 compared to the control group (p = 0.02). There were also near significant decreases of total bilirubin at day 5 and shorter length of hospitalization. Liver biopsy (at procurement, when cold, and post-reperfusion) of TG group demonstrated a trend for increased central ballooning. CONCLUSION: The TG allowed for more compromised liver grafts to be transplanted with less clinical evidence of IRI and improved function. Further studies on the degree of apoptosis in the liver biopsy post-reperfusion are underway.     

L-精氨酸对大鼠胰腺移植缺血再灌注损伤的保护作用及其机制

目的探讨L-精氨酸（L-Arginine，L-Arg）对大鼠胰腺移植缺血再灌注（I／R）损伤的影响及其机制。方法SD大鼠作为供、受体行胰腺移植术，给予不同方式处理：假手术组（Sham）：只行开腹术；对照组（Control）：只行胰腺移植术，不行预处理；缺血预处理组（IPC）：在供胰切取前阻断血供10min，然后再灌注10min；L-精氨酸组（L-Arg）：行胰腺移植术，再灌注前先经下腔静脉注射L-Arg 10mg／kg体重；L-硝基精氨酸甲酯组（L-NAME）：供胰切取时阻断血供10min，再灌注10min；然后行移植术，在再灌注前，先经下腔静脉缓慢注射L-NAME 10mg／kg体重。各组手术完成后，于再灌注6h检测血清淀粉酶、肿瘤坏死因子-α（TNF-α）和一氧化氮（NO）水平，胰腺细胞凋亡指数、胰腺细胞bcl-2蛋白表达情况和胰腺组织病理改变。结果L-Arg和IPC都降低TNF-α水平（P〈0．01）和细胞凋亡水平（P〈0．01），NO水平升高（P〈0．01）。而L-NAME可阻断该保护效应。IPC和L-Arg均能激活bcl-2蛋白的表达。结论L-Arg可以模拟IPC对大鼠胰腺移植I／R损伤的保护作用，其机制与合成NO，激活bcl-2基因的表达有关。     

人参皂甙Rb1对肺缺血再灌注损伤的保护作用

目的探讨人参皂甙Ｒｂ１对肺缺血再灌注损伤的保护作用。方法按肺移植供肺获取和保存的方法，对３５只家兔的肺分别获取，保存；然后采用体外装置，建立体外肺缺血再灌注损伤模型。在即将再灌流前，将不同剂量的Ｒｂ１加入到５０ｍｌ再灌流血液中。结果Ｒｂ１可使肺组织中超氧化物歧化酶（ＳＯＤ）含量升高，丙二醛（ＭＤＡ）含量降低；使肺动脉压（ＰＡＰ）降低，湿肺干肺比重降低和改善肺组织病理变化。Ｒｂ１在再灌流血液中浓度为８０ｍｇ／Ｌ时，已有明显效果。结论Ｒｂ１对肺缺血再灌注损伤具有明显的保护作用。     

Reperfusion of the Liver Allograft with Blue Blood: Is It Still the Royal Perfusate?

The technique of liver transplantation has become relatively standardized. Although not commonly practiced, arterial reperfusion has been shown in both animal and human trials to offer hemodynamic and functional benefits to liver allograft recipients. Whether this is the result of shortening the time to re-establishing arterial perfusion or an effect of the sequence which the liver is revascularized remains unknown. Further randomized clinical trials are needed to answer this question and support our practice of arterial reperfusion.     

Reduction of ischemia/reperfusion injury by antithrombin III after experimental pancreas transplantation

BACKGROUND: Graft pancreatitis is a major complication after pancreas transplantation. Antithrombin III (AT III) is an anticoagulatory and anti-inflammatory substance. The aim of our study was to evaluate a prophylactic application of AT III in experimental pancreas transplantation. METHODS: Pancreas transplantation was performed in rats. Cold ischemia time (University of Wisconsin solution at 4 degrees C) was 12 hours. After 4 hours of reperfusion, pancreatic enzymes were assessed and the pancreas was evaluated by intravital microscopy and histologic and immunohistochemical examination. Recipients were allocated randomly to 2 groups: 1 control group (n = 6) and 1 group in which recipients received 125 IU AT III/kg 30 minutes before reperfusion (n = 6). Six animals that did not undergo transplantation served as healthy controls. RESULTS: Enzyme levels showed no differences between the 2 transplantation groups but were significantly (P <.05) higher than in the control group. Histologic damage was significantly less evident in animals that received AT III compared with transplantation animals that did not receive AT III. During intravital microscopy, animals receiving AT III showed significantly higher capillary and venular erythrocyte velocities compared with untreated transplantation animals. The leukocyte-endothelium interaction in postcapillary venules was decreased significantly in animals with AT III treatment. CONCLUSIONS: AT III pretreatment decreases tissue damage by attenuating microcirculatory disturbances and leukocyte adherence in experimental graft pancreatitis by its anti-inflammatory and anticoagulatory properties.     

P选择素、细胞间黏附分子-1在大鼠胰腺移植缺血再灌注损伤中的作用

目的观察P选择素（Ps）和细胞间黏附分子-1（ICAM-1）在大鼠胰腺移植缺血再灌注损伤中的作用及Ps单克隆抗体的治疗作用。方法75只SD大鼠随机分为假手术组、移植组和治疗组。移植组和治疗组均进行全胰十二指肠移植术，但治疗组于再灌注前5rain静脉注射Ps单克隆抗体。3组分别于腹主动脉开放后1（n=5）、3（n=5）、6（n=5）h取血测定血清淀粉酶水平，并切取胰腺标本进行组织病理学观察及Ps、ICAM．1免疫组织化学染色。结果移植组胰腺组织损伤随再灌注时间的延长而加重，血淀粉酶升高，与中性粒细胞浸润直接相关；而治疗组胰腺组织损伤不明显，血淀粉酶减低。移植组各时段Ps、ICAM-1均有阳性表达，且Ps再灌注1h为表达高峰，ICAM．1随再灌注时间延长表达逐渐增加，假手术组、治疗组Ps、ICAM-1不表达。结论Ps及ICAM-1按一定时间顺序参与胰腺移植缺血再灌注损伤的病理过程；Ps可能是胰腺移植缺血再灌注损伤的起始因素；抗Ps单克隆抗体对移植胰腺缺血再灌注损伤有保护作用。     

一种大鼠胰腺缺血再灌注模型的建立

目的 建立一种简便实用的大鼠经腹主动脉胰腺缺血再灌注模型.方法 将60只Wistar大鼠随机分为:新模型组、对照组和假手术组,每组20只.采用显微外科技术游离胰腺,胰腺灌注后阻断血流2 h,恢复再灌注后0、2、4、6 h,切取胰腺体尾部组织,检测湿/干重比、行组织病理学分析及血清淀粉酶和脂肪酶检测.结果 再灌注后,新模型组血清淀粉酶2 h(3127.80±150.85)U/L、4 h(3122.80±131.52)U/L、6 h(2585.20±161.06)U/L;血清脂肪酶2 h(446.00±181.54)U/L、4 h(517.40±165.22)U/L、6 h(475.20±170.37)U/L;均随再灌注时间延长有明显升高趋势(P＜0.05),胰腺组织病理切片呈现逐渐加重的炎细胞浸润及组织水肿(P＜0.05)等改变.结论 本模型手术操作简便、又能够较好地模拟临床胰腺缺血再灌注的过程,是研究胰腺缺血再灌注损伤的较理想动物模型.

Abstract：

Objective To build a convenient model of pancreas ischemia reperfusion injury (IRI)in rats for investigating its negative impact on pancreas. Methods Wistar rats were randomized into 4groups:(1)sham-operated animals with dissociation of the pancreatic tail-segment ( sham, n=20 ); ( 2 )control animals with dissociation of the pancrea-tic tail-segment, 30 seconds of ischemia by bcloking the abdominal aorta and flushing(control, n=20);(3) Group New model animals experienced with dissociation of the pancreatic tail-segment, flushing, 120 mins of ischemia and reperfusion (IR, n=20). The level of serum amylase and lipase, wet to weight ratio of pancreas and pathological changes of pancreas were observed at0, 2, 4, 6 hours after reperfusion. Results The level of serum amylase[2 h (3127.80±150.85) U/L, 4 h (3122.80±131.52) U/L, 6 h (2585.20±161.06) U/L]and lipase[2 h (446.00±181.54) U/L, 4 h (517.40±165.22) U/L, 6 h (475.20 ± 170.37) U/L]in Group New model were increased significantly after perfusion accordingly, The tissue damage of pancreas become more serious after perfusion. Conclusion The model shows a typical IRl on pancreas of rats. It's a ideal and clinically relevant animal model for the study of pancreas IRI after transplantation.     

Interstitial and vascular pancreas rejection in relation to graft survival

To examine the incidence of interstitial and vascular rejection in pancreas allografts and its impact on graft survival, we studied 36 percutaneous pancreas biopsies and 10 pancreas transplantectomy specimens from 32 patients who had undergone simultaneous pancreas-kidney transplantation. Interstitial rejection (IR) was predominantly found in the biopsies, while vascular rejection (VR) was most prominent in the transplantectomies. Pancreas graft survival was significantly decreased for pancreas grafts that had suffered from vascular rejection when compared to those with only interstitial rejection. Potential rejection markers, i. e., serum amylase, glucose, creatinine, and urinary amylase, did not correlate with histological signs of rejection, although increased levels of serum amylase were, in all but one case, associated with rejection.We conclude that a percutaneous pancreas biopsy remains the most reliable method to determine pancreas rejection, and that by distinguishing between IR andVR, a pancreas biopsy may provide important diagnostic as well as prognostic information. Received: 6 March 1997 Received after revision: 5 June 1997 Accepted: 30 June 1997     

Preservation of pancreas in the University of Wisconsin solution supplemented with AP39 reduces reactive oxygen species production and improves islet graft function

Ischemia-reperfusion injury (IRI) results in increased rates of delayed graft function and early graft loss. It has recently been reported that hydrogen sulfide (H₂S) protects organ grafts against prolonged IRI. Here, we investigated whether the preservation of pancreas in University of Wisconsin (UW) solution supplemented with AP39, which is a mitochondrial-targeted H₂S donor, protected pancreatic islets against IRI and improved islet function. Porcine pancreata were preserved in the UW solution with AP39 (UW + AP39) or the vehicle (UW) for 18 h, followed by islet isolation. The islet yields before and after purification were significantly higher in the UW + AP39 group than in the UW group. The islets isolated from the pancreas preserved in UW + AP39 exhibited significantly decreased levels of reactive oxygen species (ROS) production and a significantly increased mitochondrial membrane potential as compared to the islets isolated from the pancreas preserved in the vehicle. We found that the pancreas preserved in UW + AP39 improved the outcome of islet transplantation in streptozotocin-induced diabetic mice. These results suggest that the preservation of pancreas in UW + AP39 protects the islet grafts against IRI and could thus serve as a novel clinical strategy for improving islet transplantation outcomes.     

胰岛FasL基因转染对大鼠胰岛移植的影响

目的 探究胰岛细胞FasL基因转染对同种大鼠胰岛移植的影响。方法 通过磷酸钙沉淀法构建含目的基因FasL的重组腺病毒AdV-FasL,感染胰岛细胞后移植于糖尿病受者大鼠,通过RT-PCR和免疫组织化学检测移植物FasL表达,观察移植物存活情况及基因转染胰岛细胞凋亡情况。结果 单纯移植胰岛组平均存活期为（6.3±0.56）d,FasL基因转染组并未出现排斥延迟,反而排斥加速,存活期缩短至（3.4±0.24）d。FasL转染的胰岛细胞在移植后24h见FasL表达,在 48 h表达增强,AdV-5感染组及未转染组未见FasL表达。TUNEL标记见移植后FasL转染胰岛细胞凋亡。结论 尽管表达FasL的睾丸细胞与胰岛共移植可诱导活化的淋巴细胞凋亡,使胰岛移植物获得免疫豁免、存活期延长,但通过FasL基因转染使胰岛细胞直接表达FasL,引起胰岛细胞凋亡和粒细胞浸润,导致排斥加速。     

大鼠移植胰腺冷缺血再灌注后细胞凋亡及其调控基因的研究

目的探讨胰腺移植再灌注后胰腺细胞凋亡发生的过程,以及Bax、Bcl2及Fas等调控基因的表达。方法65只SD大鼠随机分成7组假手术组,冷缺血2h组,冷缺血2h再灌注1、3、6、9、12h组。电镜观察胰腺组织的病理变化;采用缺口末端标记法(TUNEL)检测凋亡细胞;采用免疫组织化学方法检测胰腺组织中Bax、Bcl2及Fas蛋白的表达。结果胰腺移植后早期即可观察到细胞凋亡,凋亡的高峰期为再灌注后3h,凋亡指数(AI)为(95±29)%,P<001,再灌注6h组细胞凋亡有所减少,AI为(57±17)%,P<001,再灌注9h及12h组,AI分别为(36±16)%及(33±14)%,P<005。假手术组与冷缺血2h组均未见Bax、Fax蛋白表达。冷缺血再灌注1h组Bax( )、Fas( ),未见Bcl2蛋白表达;至冷缺血再灌注3h组Bax及Fas表达均增强,分别为Bax( )、Fas( ),以后各组表达有所下降。Bcl2蛋白在假手术组、冷缺血2h组及冷缺血再灌注1h组均未见表达,冷缺血再灌注3h及以后各组表达为( )。结论细胞凋亡是胰腺移植后的早期事件,Bax、Fas基因可能促进了胰腺细胞的凋亡,而Bcl2基因可能抑制细胞凋亡。     

Sertoli细胞诱导大鼠肝内胰岛移植物免疫豁免的实验研究

目的 探究睾丸Sertoli细胞能否对肝内共移植的胰岛移植物提供免疫豁免作用以及共移植的睾丸Sertoli细胞最佳数量。方法将同种大鼠胰岛及不同数量的睾丸Sertoli细胞同时移植于糖尿病受体的肝内,观察移植物存活情况、胰岛功能、并检测移植物内胰岛素和Fas配体(FasL)表达以及浸润淋巴细胞凋亡情况。结果单纯胰岛移植组平均存活期为(5.6±0.8)d,同时与胰岛细胞在肝内共移植的睾丸细胞数增加至1×107个时,平均存活期为(41.4±4.61)d,明显延长(P<0.05),胰岛移植物中有大量表达FasL的睾丸细胞和表达胰岛素的胰岛细胞.在移植物周围有大量浸润的淋巴细胞凋亡。结论睾丸Sertoli细胞与胰岛细胞同时在肝内共移植,通过诱导局部豁免而延长胰岛移植物的存活时间,且同时共移植1×107个Sertoli细胞时效果最好。     

不同热缺血时间犬自体胰移植物功能状态及存活率的实验研究

目的探讨热缺血时间较长犬胰腺移植物功能和组织形态变化状态,研究不同热缺血时间条件下移植物存活率及供胰耐受热缺血的时限。方法根据供胰热缺血不同时间30、60、90、120 min分组,用UW液保存24 h,然后行自体移植,术后连续观察血糖、静脉葡萄糖耐量试验(IVGTT)、胰液淀粉酶、胰液分泌量、血液中胰岛素含量,并进行病理学检测。结果30 min组和60 min组在术后2~3 d即可恢复至正常范围,而在90 min组和120 min组术后1周血糖不能恢复至正常。IVGTT K值在未热缺血组3、0 min组和60 min组在术后1周>1,而在90 min组和120 min组<1。30 min组和60 min组术后胰液淀粉酶、胰液分泌量、血液中胰岛素含量明显高于90 min组和120 min组(P<0.05)。热缺血30、60、90、120 min各组移植物存活率分别为100%、100%、66.7%、0%。结论移植胰腺经过30~60 min热缺血,UW液保存24 h后移植物生存良好。热缺血时间超过90 min,移植物结构和功能难以恢复,存活率明显降低。