缺血预处理对大鼠肝脏缺血再灌注损伤保护作用机制的研究

目的　探讨缺血预处理 (IPC)保护作用的发生机制。方法　建立大鼠部分肝脏热缺血再灌注模型。IPC采用肝脏缺血 10min ,再灌注 10min。结果　IPC后肝组织中腺苷和NO水平明显升高 ,与对照组相比差异显著 (P <0 0 1) ,但IPC前应用腺苷A2 受体拮抗剂后NO的升高被抑制 (P<0 0 1)。缺血再灌注 (I/R) 2h后血清中TNF α、AST、ALT、LDH及W/D水平和假手术组相比明显增加 ,而IL 10含量降低 (P <0 0 1) ;IPC、I/R前加入腺苷、IPC前应用腺苷A1受体拮抗剂显著地降低TNF α释放和AST、ALT、LDH及W /D水平 ,提高IL 10含量 ,与I/R组相比差异显著 (P <0 0 1) ;但IPC前应用腺苷A2 受体拮抗剂 (IPC +A2 antag)和NO合成酶抑制剂NAME并没有能像IPC组那样有效降低TNF α、AST、ALT、LDH及W /D的水平 ,提高IL 10的含量 (P <0 0 1) ;而IPC前给IPC+A2 antag组提供NO前体精氨酸又获得和IPC组同样的结果 (P >0 0 5 )。结论　IPC引起细胞外腺苷水平升高 ,腺苷A2 受体活化 ,介导了NO合成增加 ,最终通过抑制效应器TNF α的释放、增加IL 10的合成来实现对缺血组织的保护作用。     

缺血预处理对大鼠小体积供肝的保护作用及机制

目的探讨缺血预处理（IPC）对大鼠小体积供肝的保护作用及其机制。方法120只SD大鼠随机分为3组（每组20对）：无热缺血组（NWI）、缺血再灌注组（WI）和缺血预处理组（IPC）。用双袖套法建立大鼠小体积肝移植模型。各组10只受体大鼠于术前1d、术后1、2、3、5d取血，用自动生化分析仪检测AST和ALT。NWI组于供肝灌注前及植入后0．5、1、2、3h，WI组于热缺血前及植入后0．5、1、2、3h，IPC组于IPC前、IPC后及植入后0．5、1、2、3h取肝组织，用硝酸还原法检测其NO浓度。结果IPC可降低大鼠小体积肝移植术后血清AST和ALT浓度，提高再灌注早期肝脏组织NO的浓度，降低再灌注晚期肝脏组织NO的浓度（P〈0．05）。结论NO在大鼠肝脏的缺血再灌注损伤中可能具有双重作用。IPC对大鼠小体积供肝的缺血再灌注损伤有保护作用。其机制可能是通过促进供肝再灌注后早期NO合成，改善肝脏微循环，同时抑制供肝再灌注后晚期NO合成，减轻过量NO的损伤作用，从而保护移植肝脏功能。     

缺血预处理对大鼠部分肝脏切除术后肝脏一氧化氮合酶的影响及意义

目的 探讨缺血预处理（IPC）对大鼠部分肝脏切除术后肝脏一氧化氮合酶（NOS）的影响及意义。方法 20只SD大鼠随机分为2组：单纯热缺血组（WI）和缺血预处理组（IPC）。WI组于缺血前、再灌注后0．5、1、2、3h，IPC组于IPC前、IPC结束时、再灌注后0．5、1、2及3h分别切取肝脏组织约0．1g，用荧光定量PCR法检测其内皮型NOS（eNOS） mRNA和诱导型NOS（iNOS） mRNA。结果 两组肝脏热缺血再灌注后早期eNOS mRNA表达均增强，IPC组的表达高于WI组（P〈0、01或P〈0．05）。两组肝脏热缺血再灌注1h后iNOS mRNA开始表达，IPC组的表达低于WI组（P〈0．05）。结论 IPC可能通过促进肝脏热缺血再灌注早期eNOS mRNA的表达和抑制其稍后iNOS mRNA的表达，而发挥其对大鼠肝脏切除术中肝脏热缺血再灌注损伤的保护作用。     

缺血预处理对大鼠肝脏缺血再灌注损伤的保护机制

目的验证缺血预处理(IPC)对大鼠肝脏缺血再灌注损伤(I/R)的保护作用,探讨一氧化氮(NO)与蛋白激酶C(PKC)在IPC过程中的作用.方法在原位灌流的大鼠肝脏缺血再灌注模型上,观察IPC的保护作用.同时经肠系膜上静脉注射NO前体L-精氨酸和蛋白激酶C特异性激动剂1,2-二辛酸甘油(DOG)以及两者的特异性阻滞剂N-硝基-L-精氨酸甲酯(NAME)和多粘菌素B,来检测NO和PKC在IPC中的关系.结果预处理可阻止血清谷丙转氨酶(ALT)[(200.86±40.30)U/Lvs.(257.65±20.18)U/L],谷草转氨酶(AST)[(211.06±13.59)U/Lvs.(309.17±24.79)U/L],乳酸脱氢酶(LDH)[(824.73±127.11)U/Lvs.(1118.60±82.21)U/L]及脂质过氧化物(LPO)[(0.414±0.069)mmol/mgvs.(0.531±0.054)mmol/mg]水平升高(P＜0.05),而使组织超氧化歧化酶(SOD)保持在较高水平[(10.33±0.88)U/mgvs.(6.01±0.91)U/mg],(P＜0.05).NO与PKC均可模拟预处理的保护效应.结论缺血预处理对大鼠肝脏I/R有明确的保护作用,NO与PKC发挥IPC保护作用的途径不同.     

不同时限缺血预处理对硬化肝脏保护作用的实验研究

目的: 探讨缺血预处理对硬化肝脏缺血再灌注的作用,并寻找一种有效缺血预处理的时间窗和理想方案. 方法: 将64只雄性、肝硬化SD大鼠随机分为八组,每组八只:假手术组(SO组);缺血再灌注组(I/R组);缺血预处理1、2、3、4、5和6组(IPC1、IPC2、IPC3、IPC4、IPC5和IPC6).以肝组织ATP、ADP、AMP及EC(用高效液相色谱法测定),血清ALT、AST、LDH(用全自动生化仪测定)和肝脏胆汁分泌量来评价肝功能. 结果: 再灌注末,IPC3组、IPC4组、IPC5组ATP含量均明显高于I/R组(P分别为0.01、0.07和0.000);同样,测定EC时发现,IPC3组、IPC4组和IPC5组均明显高于I/R组(P=0.000).与I/R组比较,IPC4组和IPC5组的血清ALT差异有显著性(P分别为0.013和0.000);其血清LDH差异亦有显著性(P=0.023,P=0.000),而血清AST却只有IPC5组显著低于I/R组(P=0.001).IPC3组、IPC4组和IPC5组肝脏的胆汁分泌量明显高于I/R组(P=0.028,P=0.023,P=0.008). 结论: 5~10min予一次或两次缺血预处理,能启动IPC对肝硬化大鼠肝脏I/R损伤的保护作用;10 min的缺血预处理,对肝硬化大鼠肝脏I/R损伤的保护作用最强.     

肢体缺血预处理对大鼠肝脏缺血再灌注损伤的影响

目的探讨肢体缺血预处理对大鼠肝脏缺血再灌注损伤的保护作用。方法将32只Wistar大鼠随机分为假手术组(SO)、肝脏缺血再灌注组(IR)、肝脏缺血预处理组(IPC+IR)和肢体缺血预处理组(LIPC+IR)。观察术后各组大鼠血液中炎症因子(IL-6,TNF-α)及氧化应激水平的差异;同时观察各组大鼠术后生存率及肝脏酶学水平的差异。结果 LIPC组及IPC组大鼠术后血清AST、ALT均较IR组明显降低,术后第7天存活率较IR组明显提高,术后血清TNF-α、IL-6均较IR组明显降低,差异均有统计学意义(P0.05)。LIPC组与IPC组比较无统计学意义(P0.05)。LICP及ICP组大鼠术后体内MDA水平均较IR组降低,SOD水平均较IR组显著升高,差异均有统计学意义(P0.05)。结论肢体缺血预处理能减轻大鼠肝脏缺血再灌注损伤,可能与减轻肝脏氧化应激水平有关。     

白术多糖预处理对大鼠肝脏缺血再灌注损伤的实验研究

目的:研究白术多糖(AMP)对大鼠肝脏缺血再灌注损伤的影响及作用机制。方法:将72只成年雄性SD大鼠随机分成3组:假手术组(Sham组)、缺血再灌注组(HIRI组)、AMP预处理缺血再灌注组(AMP组)。缺血60 min后分别再灌注1、6、24 h后取材,测定血清谷丙转氨酶(ALT)、谷草转氨酶(AST)及一氧化氮(NO)、内皮素(ET-1)水平,光镜及透射电镜下观察各组肝细胞的显微结构及超微结构变化。结果:AMP组及HIRI组ALT、AST水平均高于Sham组;与HIRI组比较,AMP组ALT、AST水平显著降低(P<0.05)。与Sham组比较,HIRI组及AMP组术后各时段的NO水平均明显降低,ET-1水平明显升高,术后6 h时明显(P<0.05);与HIRI组相比较,AMP组术后各时段NO水平升高,而ET-1水平降低,差异有统计学意义(P<0.05)。光镜下HIRI组大鼠肝细胞肿胀、变性坏死,肝血窦变窄、淤血及炎性细胞浸润等,而AMP组明显好转。电镜下HIRI组大鼠肝细胞线粒体细胞核皱缩变形,染色质粗糙,核仁浓缩甚至裂解,部分膜破裂,线粒体嵴疏松溶解等,而AMP组明显好转。结论:AMP可以提高缺血再灌注大鼠体内NO水平,同时降低ET-1水平,改善肝脏微循环障碍,对肝脏起保护作用。     

一氧化氮在缺血预处理保护大鼠移植肝脏再灌注损伤中的作用

目的　探讨一氧化氮 (NO)在缺血预处理 (IP)保护大鼠移植肝脏缺血再灌注损伤中的作用。方法　采用SD大鼠原位肝移植动物模型 ,供肝冷保存时间为 10 0min ,无肝期 2 5min。12 8只大鼠随机分成 4组 (n =32 ) :A组 (对照组 )、B组 (IP组 )、C组 [腺苷 (Ade)组 ]、D组 [NO合成抑制剂N L 精氨酸甲基脂 (NAME)组 ]。其中各组的半数用于观察存活率 ,另一半用于移植肝脏再灌注 2h后取血及肝脏检测。结果　IP组和Ade组的 1周存活率、胆汁分泌量、抗氧化酶活力及血清NO水平均明显高于对照组 (P <0 .0 5 ) ,血清丙氨酸氨基转移酶 (ALT)、肿瘤坏死因子(TNF)及肝组织中的过氧化物含量均明显低于对照组 (P <0 .0 5 )。肝组织损伤以窦状内皮细胞为主 ,并且是以凋亡的方式发生死亡 ,IP组和Ade组窦状内皮细胞损伤明显轻于对照组 (P <0 .0 0 1) ;NAME组的各种观察结果与对照组相近 (P >0 .0 5 )。结论　IP能够通过增加NO的合成来减轻再灌注早期窦状内皮细胞所受到的损伤 ,改善微循环 ,提高移植肝脏的功能。     

百里醌预处理对大鼠肝脏缺血再灌注损伤的作用及机制

目的探讨百里醌(TQ)对大鼠肝脏缺血再灌注损伤(IRI)的保护作用及分子机制。方法建立大鼠肝脏IRI模型,肝脏缺血再灌注前,实验大鼠进行百里醌给药预处理。通过酶联免疫吸附试验(ELISA)测定血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)水平,检测肝脏组织谷胱甘肽过氧化物酶(GPX)、谷胱甘肽(GSH)、超氧化物歧化酶(SOD)、丙二醛(MDA)等酶活性;蛋白印迹法(Western blotting)检测肝脏组织凋亡相关蛋白。实验设3组:假手术组(Sham组,n=10)、缺血再灌注组(IRI组,n=10)、百里醌预处理+肝缺血再灌注组(TQ+IRI组,各亚组n=10)。结果与Sham组比较,IRI组大鼠血清ALT、AST水平显著增高,TQ+IRI组ALT、AST较IRI组明显降低(P0.05)。IRI组与Sham组比较,大鼠肝脏组织中GPX、GSH、SOD含量均明显下降(P0.05),而MDA含量显著增高(P0.05);TQ+IRI组与IRI组比较,GPX、GSH、SOD含量均显著上升(P0.05),MDA含量下降(P0.05)。百里醌预处理能下调肝脏IRI的Bax、裂解的胱天蛋白酶(Cleaved-caspase)-3、Cleaved-caspase-9表达,阻断肝细胞凋亡。结论百里醌可能通过调控肝细胞氧化应激诱导的细胞凋亡进而在肝脏IRI中发挥肝脏保护作用。     

缺血预处理对大鼠肝脏低温保存损伤的保护作用

目的　探讨缺血预处理 (IPC)对大鼠肝脏低温保存损伤的保护作用。方法　制备大鼠肝脏离体非循环灌注模型 ,对供肝分别作不同时间的IPC (IPC1组缺血 5min、IPC2 组缺血 10min、IPC3 组缺血 15min) ,而后比较各组供肝的损伤程度。结果　流出液中AST和ALT的水平 ,IPC1组分别为 (4 0 .1± 6.3 )U/L和 (17.1± 0 .5 )U /L ,IPC2 组分别为 (5 3 .6± 3 .7)U/L和 (19.7± 0 .5 )U /L ,均显著低于未预处理 (NPC)组的 (64 .5± 8.2 )U/L和 (2 3 .8± 3 .9)U /L (P<0 .0 5 ) ;IPC1组又显著低于IPC2 组和IPC3 组的 (63 .8± 7.2 )U/L和 (2 2 .8± 2 .5 )U /L (P<0 .0 5 )。LDH水平 ,NPC组、IPC1组、IPC2 组和IPC3 组分别为 (10 4.3± 2 0 .6)U/L、(84.1± 19.7)U /L、(90 .5± 2 1.1)U/L和 (10 3 .1± 18.5 )U /L ,4组间差异无统计学意义 (P>0 .0 5 ) ,但均高于正常组〔(71.5± 18.9)U /L〕 (P<0 .0 5 )。胆汁分泌量及肝组织ATP含量 ,IPC1组分别为 (5 3 .5± 10 .2 ) μl和 (6.15± 0 .65 ) μmol/g ,IPC2 组分别为 (4 1.5± 8.1) μl和 (4 .77± 0 .2 1) μmol/g ,均显著高于NPC组的 (2 2 .8± 9.7) μl和 (2 .62± 0 .3 4) μmol/g (P<0 .0 5 ) ;IPC1组又显著高于IPC2 组和IPC3 组的 (2 7.5± 2 .8) μl和 (2 .61     

Intermittent Ischemic Preconditioning Protects Against Hepatic Ischemia-Reperfusion Injury and Extensive Hepatectomy in Steatotic Rat Liver

ABSTRACT

Background: Hepatic steatosis causes severe liver damage and has deleterious effects when associated with ischemia-reperfusion mechanisms. Ischemic preconditioning (IPC) protects lean liver against prolonged ischemia by improving micro-circulation and reducing lipid peroxidation. We investigated the effect of intermittent IPC on liver ischemia-reperfusion injury (IRI) and extensive hepatectomy in severe hepatic steatosis. Methods: Severe hepatic steatosis was performed by 12–14 weeks of choline-free diet in 108 Wistar rats. We induced 30-minute ischemia-reperfusion manipulations and extensive hepatectomy with or without prior IPC in steatotic livers and after 6 and 24 hours of reperfusion blood transaminases, and IL6, TNFα, NO and Lactate in blood and liver tissue were measured. Results: Steatotic rats subjected to hepatic ischemia-reperfusion alone after extensive hepatectomy, showed severe liver damage with significantly increased values of AST, ALT, TNFα and Lactate and significantly reduced IL6 and NO, while no one rat survived for more than 29 hours. On the contrary, steatotic rats subjected to intermittent IPC, 24 hours before ischemia-reperfusion, presented increased 30-day survival (67%), lower values of AST, ALT, TNFα and Lactate, and increased IL6 and NO levels. Simple and intermittent IPC manipulations, 1 hour before the IRI and extended hepatectomy, did not prolong survival more than 57 and 98 hours, respectively. Simple IPC, 24 hours before IRI and extended hepatectomy had the lowest possible survival (16.7%).Conclusions: Hepatic steatosis and IRI after major liver surgery largely affect morbidity and mortality. Intermittent IPC, 24 hours before IRI and extensive hepatectomy, presents higher 30-day survival and improved liver function parameters.     

一氧化氮和内皮素在肝脏再灌注损伤和缺血预处理中作用的研究

目的 :观察缺血预处理一氧化氮 (NO)和内皮素 (ET)的变化及其与再灌注损伤和微循环变化的关系。方法 :建立大鼠肝脏 70 %缺血再灌注损伤模型 ,分为对照组、缺血组、缺血预处理组、L 精氨酸组、L NAME组 ,观察各组肝功能变化 ,检测肝组织和血清中NO和ET及透明质酸 (HA)的水平 ,以HA代表肝脏微循环情况。结果 :再灌注损伤后微循环的破坏和NO和ET的变化相关 ,缺血预处理可减少NO水平的下降和血浆ET升高 ,减少微循环破坏和肝功酶的升高 (P <0 .0 5 )。外源性给予NO合成前体L 精氨酸在升高NO水平降低ET水平的同时 ,可达到类似预处理的保护作用。结论 :血管活性介质NO的减少和ET水平增加是导致再灌注损伤微循环变化的原因之一。缺血预处理可诱导增加NO和减少ET ,并可能是其改善微循环和减少再灌注损伤的因素之一。给予外源性NO可起到类似缺血预处理的保护效果 ,而抑制NO产生并不能加重再灌注损伤。     

Lack of protection of ischaemic preconditioning in the rat model of major hepatectomy with ischaemia reperfusion injury

OBJECTIVE: To investigate the effects of ischaemic preconditioning (IP) on residual liver regeneration after major hepatectomy without portal blood bypass in rats, and to verify whether it can protect the residual liver from ischaemia reperfusion (IR) injury. METHODS: Ninety rats were randomized into three groups: Group PH, rats were subjected to 70% hepatectomy alone; Group IR, rats were subjected to 30 minutes of total hepatic ischaemia, and 70% hepatectomy was performed just before reperfusion; Group IP, rats were pretreated with IP (5/10 minutes). During the preoperative period and at 0.5, 6, 12, 24 and 48 hours after the operation, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were measured using an autoanalyser. Serum hyaluronic acid (HA) was measured by radioimmunoassay. Regenerated liver weight (RLW) of the rats was measured and the expressions of Ki-67 and cyclin D1 were determined by immunohistochemistry in remnant liver tissue. RESULTS: There were no significant differences in serum AST and ALT levels in all the groups before the operation. After partial hepatectomy, AST and ALT levels increased rapidly. From 0.5 to 24 hours after operation, serum AST and ALT levels were significantly higher in IP group rats than in PH and IR rats (p < 0.05). There were no significant differences in serum HA levels in all the groups before the operation. After partial hepatectomy, HA levels increased rapidly, reaching peak values at 12 hours. In the early stage (during 12 hours) after the operation, HA level was significantly higher in IP rats than in PH and IR rats (p < 0.05). The RLW of the rats rapidly increased after partial hepatectomy, and significantly decreased in IP rats compared with PH and IR rats (p < 0.05). Cyclin D1 and Ki-67 expression in all groups before the operation were low and were not significantly different. After partial hepatectomy, they rapidly increased. The expression of Ki-67 and cyclin D1 reached a peak at 24 hours after the operation in PH rats, and they were significantly higher compared with IR and IP rats (p < 0.05). In groups IR and IP, the expression of cyclin D1 and Ki-67 reached peak values at 48 hours. A significant decrease (p < 0.05) was observed after 24 and 48 hours of reperfusion in group IP compared with groups PH and IR. CONCLUSION: IP impairs residual liver regeneration after major hepatectomy without portal blood bypass in rats, and protection from IR injury disappears. IP-induced hyperperfusion may be the cause of reduced liver regeneration.     

Effects of ischemic preconditioning on regenerative capacity of hepatocyte in the ischemically damaged rat livers

BACKGROUND: Liver regeneration after partial hepatectomy is regulated by several factors that activate or inhibit hepatocyte proliferation. A short period of ischemia-reperfusion (IR), called ischemic preconditioning (IPC), protects the liver against subsequent sustained ischemic insults. The present study investigated the effects of IPC on liver regeneration after partial hepatectomy under IR in rats. MATERIALS AND METHODS: Male Wistar rats were subjected to 45 min of total hepatic ischemia, and 70% hepatectomy was performed just before reperfusion. Animals were pre-treated with either IPC (10/15 min) (IPC + PHx group) or not (ischemia + PHx). The survival rate, serum transaminases, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-6 levels, hepatocyte proliferation and histological change of the remnant liver were measured in both groups and compared with non-ischemic controls subjected to 70% hepatectomy alone (PHx group). RESULTS: The survival rate was significantly better in the IPC + PHx group than in the ischemia + PHx group. Furthermore, IPC reduced liver injury determined by liver histology and serum transaminases. There was an early rise in serum TNF-alpha and IL-6 levels in the ischemia + PHx group. Compared with non-ischemic controls, IPC significantly decreased TNF-alpha, but not IL-6 during the late (24 and 48 h) phases of reperfusion. Rats subjected to 70% hepatectomy and 45 min of hepatic ischemia showed significantly reduced hepatocyte proliferation (mitotic index, proliferating cell nuclear antigen, and relative liver weight) when compared with animals subjected to hepatectomy alone. However, hepatocyte proliferation was markedly increased in rats pretreatment with IPC when compared with ischemic controls. CONCLUSION: These results suggest that ischemic pre-conditioning ameliorates the hepatic injury associated with ischemia-reperfusion and has a stimulatory effect on liver cell regeneration that may make it valuable as a hepatoprotective modality. Il-6 appears to be key mediator in promoting regeneration after combined ischemia and hepatic resection.     

大鼠部分肝缺血再灌注损伤后切除对肝再生的影响

目的 观察大鼠部分肝缺血再灌注损伤后切除对残肝再生的影响.方法 将75只健康雄性SD大鼠随机分为5组:肝脏左叶和中叶(约占全肝70%)切除组(Control组)、肝脏左叶和中叶缺血10min再灌注30min后切除组(I10R30组)、类推得到I60R30组、I90R30组、I90R60组.术后6、12、24h等时间点,测定再生肝重量(RLW);自动生化分析仪检测血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)含量;酶联免疫吸附试验(ELISA)检测血清肿瘤坏死因子(TNF)-α含量;通过免疫组织化学法检测残肝增殖细胞核抗原(Ki-67)表达.结果 术后12h,I60R30、I90R30和I90R60组RLW值分别为(1.80±0.03)%、(1.82±0.10)%、(1.87±0.05)%;Ki-67值分别为(58.35±2.18)%、(59.73±3.06)%、(62.65±2.24)%,均明显高于对照组(P<0.05).缺血再灌注干预各组ALT和AST明显高于对照组(P<0.05).术后6h和12h,I60R30、I90R30和I90R60组TNF-α明显高于对照组(P<0.05).结论 大鼠即将被切除的肝脏先缺血再灌注后切除,对残肝再生具有促进作用;诱导产生的TNF-α表达量增多是促进肝再生的原因之一.

Abstract：

Objective To investigate the effects of ischemia reperfusion injury before partial hepatectomy on liver regeneration in rats. Methods Seventy-five male healthy SD rats were randomly classified into 5 groups: group control, in which rats were only subjected to 70% hepatectomy; group I10R30, 70% liver hepatectomy after 10 min of ischemia and 30 min of reperfusion in the resected liver; By analogy, group I60R30, group I90R30 and group I90R60 were constructed. At 6th, 12th and 24th h after operation, RLW was determined; serum alanine aminotransferase (ALT) and aspartate transaminase (AST) activities were measured by using autoanalyzer; the levels of serum tumor necrosis factor (TNF)-α were determined by ELISA and the expression level of Ki-67 was detected by using immunohistochemical methods in the residual liver tissues. Results At 12th h after partial hepatectomy, the rate of RLW in group I60R30, group I90R30 and group I90R60 was (1.80±0.03)%, (1.82±0.10)%, (1.87±0.05)% respectively; the rate of Ki-67 was (58.35±2.18)%, (59.73±3.06)%, (62.65±2.24)% respectively, which was significantly higher than that in the group control (P<0.05). The levels of ALT and AST in rats with ischemia reperfusion injury were higher than in the group control (P<0.05). At 6th h and 12th h after operation, the expression levels of TNF-α in groups I60R30, I90R30 and I90R60 were significantly higher than those in the group control (P<0.05). Conclusion Ischemia reperfusion injury in the resected liver before partial hepatectomy could improve liver regeneration of the remnant liver in rats. The high expression of induced TNF-α may be one of the reasons.     

间断低氧预适应对大鼠肝切除缺血再灌注肝脏中EPO的影响

目的 观察术前间歇性低氧预适应对大鼠70％肝切术后肝脏中促红细胞生成素（Erythropoietin,EPO）量的影响.方法 健康清洁级SD大鼠120只,简单随机分为3组：假手术组（Sham,S组）40只;单纯大部肝切除组40只（Major hepatectomy,MH组）,即在肝门阻断下切除肝脏的左叶和中叶,肝门阻断20 min;间断低氧预适应组40只（Intermittent hypoxia preconditioning,IHP组）,术前1周将大鼠置于氧气体积分数10％的低氧环境中,每天1次,每次60 min.1周后在肝门阻断下行肝切除术（同IR组）.各组分别于术后2、6、12、24、48、72、120、168 h进行取材检测,用全自动生化分析仪检测下腔静脉血清ALT、AST含量,电镜下观察残余肝细胞中线粒体及内质网等的变化,采用ELISA测定残肝组织中促红细胞生成素的量,并运用统计学的方法比较各组中的意义.结果 MH组、S组、IHP组3组实验组中术后大鼠残肝组织中EPO水平具有显著统计学差异（P＜0.05）,间断低氧预处理组残余肝脏中EPO含量明显高于单纯肝切除组.结论 间断性低氧预适应可以促进肝切除术后残余肝组织中EPO的表达.     

The protective mechanism of magnolol,a Chinese herb drug,against warm ischemia-reperfusion injury of rat liver

BACKGROUND: Cell apoptosis following warm ischemia-reperfusion injury is a major concern in clinical issues such as organ transplantation, trauma, and cardiogenic shock. The purpose of this study was to evaluate the possible role of magnolol, a Chinese herb drug, in apoptotic injury and the kinetic expression of apoptotic-related genes in rat livers subjected to warm ischemia-reperfusion (WI/R). MATERIALS AND METHODS: Three weeks prior to the experiment 10 rats underwent a portosystemic shunt operation according to Bengmerk's method. The rats were divided into three groups. Group 1 (GI) was the control group, Group 2 (GII) and Group 3 (GIII) the magnolol-treated groups. GI and GII were subjected to 2 h and GIII to 3 h of WI/R by clamping the portal vein and hepatic artery under ether anesthesia. RESULTS: Results show that all the control rats died after 2 h WI/R. Apoptotic cells were detected under microscopy as well as by DNA assay. Magnolol-treated groups tolerated warm ischemia-reperfusion for 2 h and significantly less apoptotic cells were observed (198 +/- 22 vs 42.6 +/- 28). But magnolol-treated rats could not tolerate 3 h warm ischemia-reperfusion. RT-PCR of liver tissue shows that there is an upregulated expression of the anti-apoptotic Bcl-xL gene and suppression of the Bcl-xS gene in GII. CONCLUSION: Magnolol has an anti-apoptotic effect and protects the liver against WI/R for 2 h but not for 3 h through upregulation of the anti-apoptotic Bcl-XL gene and suppression of the Bcl-xS gene.     

不同时间的缺血预处理对肝硬化大鼠缺血再灌注损伤的保护作用

目的 探讨缺血预处理(IPC)对肝硬化大鼠缺血再灌注损伤(I/R)的保护作用,并寻找对肝硬化I/R保护作用的最佳有效时间窗和理想方案.方法 通过构建正常大鼠及肝硬化大鼠模型,以正常肝脏I/R(A组)和正常肝脏10-10 min-IPC方案(B组)为对照组,肝硬化组则分别施行单纯I/R(C组)、5-10 min(D组)、8-10min(E组)、10-10 min(F组)及15-10 min(G组)的IPC方案,每组18只,分别在术后1 h、4 h及24 h三个时间点采静脉血,检测血清ALT、AST、LDH及肝组织中MDA、MPO、NO、SOD水平,评价肝功能及肝脏组织炎性浸润及抗损伤程度.结果 肝脏缺血30 min后肝脏功能受损明显,表现为各组的ALT、AST、LDH水平升高,尤以再灌注4 h时显著(P<0.05),但经过缺血预处理后,各IPC组中的NO、MDA、MPO及SOD水平亦显著高于其对应的I/R组,以E组的差别有显著意义(P<0.05).结论 10-10 min的IPC方案对于正常肝脏I/R确有保护作用,而8-10 min的IPC方案能最有效地启动对肝硬化大鼠肝脏I/R的保护作用.     

腹腔镜下不同左肝切除方式治疗左肝胆管结石的对比研究

目的 对比腹腔镜左肝蒂阻断解剖性左半肝切除、腹腔镜左肝蒂阻断左肝部分切除、腹腔镜Pringle法阻断左肝部分切除治疗左肝胆管结石的临床疗效,探讨腹腔镜下三种左肝切除方式治疗左肝胆管结石的合理选择。方法 回顾性分析2015 年5 月至2018 年11 月四川绵阳四0 四医院97 例腹腔镜左肝切除术患者的临床资料,其中腹腔镜左肝蒂阻断解剖性左半肝切除术25 例（区域阻断+解剖性切除组）,腹腔镜左肝蒂阻断左肝部分切除术33 例（区域阻断+部分切除组）,腹腔镜Pringle法阻断左肝部分切除术39 例（全肝阻断+部分切除组）,对比分析三组围手术期结果、术后炎症和肝脏生化指标、术后并发症情况。结果 三组术中失血量、输血率、术后进食时间、术后住院时间、术后炎症指标变化、术后并发症发生率均无统计学差异（P＞0.05）;手术时间区域阻断+解剖切除组最长、区域阻断+部分切除组次之、全肝阻断+部分切除组最短[（257.9±66.2）min vs（ 234.6±49.1）min vs（ 216.4±40.2）min],差异有统计学意义（P＜0.05）。三组白细胞计数、C反应蛋白、谷丙转氨酶、总胆红素及白蛋白均出现术后先升高后降低的趋势,至术后第5 天,除白蛋白外各炎症及肝功能指标区域阻断+解剖性切除组均低于区域阻断+部分切除组和全肝阻断+部分切除组,除C反应蛋白外各炎症及肝功能指标全肝阻断+部分切除组均高于区域阻断+解剖性切除组和区域阻断+部分切除组;采用重复测量的方差分析进一步比较,白细胞计数、C反应蛋白、谷丙转氨酶、总胆红素及白蛋白在各时间点的差异均有统计学意义（P＜0.05）,谷丙转氨酶、总胆红素不同手术方式和各时间点存在交互作用（P＜0.05）,提示三组谷丙转氨酶、总胆红素随时间改变的趋势存在统计学差异。结论 （1）结石及病灶累及左内叶尤其IVa段时,选择腹腔镜左肝蒂阻断解剖性左半肝切除疗效更佳;（2）结石及病灶限于IVa段以外的左肝区段时,联合术中超声的腹腔镜左肝部分切除更具优势。