缺血预处理对肺缺血再灌注损伤的影响

目的观察缺血预处理（ＩＰＣ）对肺缺血再灌注（Ｉ／Ｒ）损伤的影响。方法建立兔单肺原位热缺血再灌注损伤模型。３０只兔分Ｉ／Ｒ组、ＩＰＣ组和对照组。对比观察各组平均动脉压、动脉血氧分压、肺组织１２５Ｉ标记牛血清白蛋白漏出量、肺湿干重比、髓过氧化物酶活性。结果经９０分钟缺血１８０分钟再灌注后,ＩＰＣ组肺组织１２５Ｉ标记牛血清白蛋白漏出量、肺湿干重比、髓过氧化物酶活性低于Ｉ／Ｒ组（Ｐ＜０．０５）,平均动脉压、动脉血氧分压高于Ｉ／Ｒ组（Ｐ＜０．０５）。结论ＩＰＣ能减轻肺Ｉ／Ｒ导致的肺毛细血管通透性增高、中性粒细胞浸润,减轻肺Ｉ／Ｒ引起的平均动脉压和动脉血氧分压的下降程度,表明ＩＰＣ能减轻肺Ｉ／Ｒ损伤。     

热缺血再灌注损伤时肝细胞凋亡的变化

越来越多的研究表明 ,细胞凋亡在肝脏缺血再灌注损伤这一过程中发挥着重要作用。本文探讨肝脏缺血再灌注时细胞凋亡的变化。一、材料与方法1.本实验采用健康雄性Ｗｉｓｔａｒ大鼠 2 4只 ,随机分成 4组 ,每组 6只 :(1)假手术组 :只做大鼠肝脏的游离 ,目的是作为正常对照以排除手术因素对实验结果的影响 ;(2 )对照组 :阻断大鼠肝左叶和中叶的门静脉、肝动脉 6 0ｍｉｎ后 ,立即切取左叶和右叶肝组织标本检测 ;(3)实验组 1:阻断血流操作同对照组 ,恢复血流再灌注 2ｈ后 ,切取左叶和右叶肝组织标本检测 ;(4)实验组 2 :操作同实验组 1,在再灌注 2 …     

缺血预处理对肢体缺血再灌注损伤的影响

目的　观察缺血预处理 (IPC)对肢体缺血再灌注损伤的影响。方法　选择 2 0例需充气止血带止血进行手术的患者 ,随机分为对照组 (n =10 )和IPC组 (n =10 )。IPC组患者术前应用 3次 5min循环缺血 ,间隔 5min再灌注预处理后在止血带下进行手术 ;对照组直接在止血带下进行手术。在肢体缺血前和再灌注 30min、90min、180min分别取静脉血检测血清肌酸磷酸激酶 (CPK)、谷草转氨酶(AST)、乳酸脱氢酶 (LDH)、丙二醛 (MDA)和过氧化物歧化酶 (SOD)水平。结果　随着肢体缺血再灌注时间的延长 ,血中CPK、AST、LDH、MDA含量逐渐升高 ,而SOD活性逐渐降低。IPC组在缺血前及再灌注同时间 ,血中CPK、AST、LDH、MDA含量低于对照组 (P <0 0 5 ,P <0 0 1) ;而SOD活性高于对照组 (P <0 0 5 ,P <0 0 1)。结论　IPC能有效地减轻肢体缺血再灌注损伤程度 ,减轻脂质过氧化反应 ,提高肢体缺血耐受性     

缺血预处理对肢体缺血-再灌注损伤影响的临床观察

198 6年Ｍｕｒｒｙ等[1] 应用缺血预处理 (ｉｓｃｈｅｍｉｃ ｐｒｅｃｏｎｄｉｔｉｏｎｉｎｇ ,ＩＰＣ) ,即短时间重复缺血间断再灌注改善心肌缺血 再灌注损伤获得成功后 ,ＩＰＣ提高组织缺血耐受性的现象颇受关注[2 ] 。目前尚鲜见到骨骼肌ＩＰＣ的临床研究报道。为此 ,我们观察了ＩＰＣ改善肢体缺血 再灌注损伤的临床效果 ,现报道如下。一、对象与方法1.一般资料 :选择需气囊止血带下进行手术的患者 2 0例 ,其中男 13例 ,女7例 ,年龄 17～ 3 2岁 ,平均 2 3岁。尺桡骨骨折切开复位钢板内固定术 6例 ,半月板切除或修整术合并韧带修复术 3例…     

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。     

缺血预处理对肝脏缺血再灌注损伤中内毒素血症的影响

目的 探讨肠源性内毒素在肝脏缺血再灌注损伤中的作用以及缺血预处理对肠源性内毒素的影响。方法 将３０只ＷＥｉｓｔａｒ大鼠随机分成３组（每组１０只）,缺血再灌注组（ｉｓｃｈｅｍｉａ／ｒｅｐｅｒｆｕｓｉｏｎ,Ｉ／Ｒ）,缺血预处理组（ｉｓｃｈｅｍｉｃ ｐｒｅｃｏｎｄｉｔｉｏｎｉｎｇ,ＩＰＣ）和正常对照组。用自动生化仪测定各组丙氨酸转氨酶（ＡＬＴ０和乳酸脱氢酶（ＬＤＨ）;用鲎试剂法测定血浆内毒素;用免疫组织     

缺血预处理联合后处理对大鼠肾缺血再灌注损伤的影响

目的 评价缺血预处理联合后处理对大鼠肾缺血再灌注损伤的影响.方法 健康雄性SD大鼠30只,体重250～280 g,随机分为5组(n=6):假手术组(S组)、缺血再灌注组(I/R组)、缺血预处理组(IP组)、缺血后处理组(IPo组)和缺血预处理联合后处理组(IP+IPo组).S组仅开腹,游离双侧肾脏,分离双侧肾蒂但不夹闭.采用夹闭双侧肾蒂45 min、再灌注6 h的方法 制备肾缺血再灌注模型.IP组夹闭双侧肾蒂5 min,再灌注5 min,反复3次,余操作同I/R组;IPo组夹闭双侧肾蒂45 min后,再灌注10 8,缺血10 s,反复3次,再灌注6 h.于再灌注6 h时,经心脏抽血后迅速处死大鼠取肾,测定血清肌酐(Cr)和尿素氮(BUN)的浓度;采用硫代巴比妥酸法测定肾组织丙二醛(MDA)含量,采用黄嘌呤氧化酶法测定肾组织超氧化物歧化酶(SOD)活性;光镜下观察肾组织病理学结果 ;TUNEL法检测肾组织凋亡细胞,计算凋亡指数(AJ).结果 与S组比较,其余各组血清Cr和BUN的浓度升高,肾组织SOD活性降低,MDA含量和AI升高(P<0.05);与I/R组比较,IP组、IPo组和IP+IPo组血清Cr和BUN的浓度降低,肾组织SOD活性升高,MDA含量和AJ降低(P<0.05),肾损伤减轻;与IP组和IPo组比较,IP+IPo组肾组织SOD活性升高,AI降低(P<0.05),肾损伤减轻.结论 缺血预处理联合后处理可减轻大鼠肾缺血再灌注损伤,较单独应用时效果好.     

缺血预处理对大鼠冷保存供肝细胞HMG-CoA还原酶活力的影响

目的 观察缺血预处理对大鼠冷保存供肝细胞HMG-CoA还原酶(HMGCR)活力的影响,探讨缺血预处理减轻大鼠供肝冷保存损伤的机制.方法 将25只大鼠随机分为对照组(C组)、冷保存组(Ⅰ组)、缺血预处理组(IP组)、阿托伐他汀30 μmol/L和100μmol/L处理组(A30组和A100组),每组5只.C组为正常大鼠肝脏,4℃UW液灌注;Ⅰ组为灌注后冷保存8 h;IP组先给予缺血预处理,灌注后冷保存8 h;A30组和A100组先给予缺血预处理,用终质量浓度为30μmol/L和100μmol/L的阿托伐他汀UW液灌注后再置入含30μmol/L和100μmol/L的阿托伐他汀UW液中4℃冷保存8 h.分别测定5组大鼠肝脏的HMGCR活力.结果 供肝经过8 h冷保存后(Ⅰ)HMGCR活性为(1872±157)nmol/(min·mg),与对照组(C)(3298±224)nmol/(min·mg)比较明显下降(P＜0.05),给予缺血预处理后再给予冷保存(IP),则HMGCR活性为(3746±231)nmol/(min·mg),明显升高(P＜0.05);给予缺血预处理同时给予HMGCR抑制剂阿托伐他汀则HMGCR活性则受到明显抑制,并随着阿托伐他汀浓度的增加而抑制效应更为明显,A30组、A100组HMGCR酶活力分别为(2010±193)nmol/(min·mg)、(1469±132)nmol/(min·mg),同IP组比较明显下降(P＜0.05).结论 缺血预处理可以明显提高HMGCR活力,而阿托伐他汀则可消除缺血预处理升高HMGCR活性的作用;缺血预处理升高HMGCR活力的机制是增加HMGCR蛋白的表达.

Abstract：

Objective To investigate the effects of ischemic preconditioning on the activity of 3-hydroxy-3-methylglutary coenzyme A reductase (HMGCR) of hepatocytes following cryopreservation in rats. Methods Twenty-five rats were randomly divided into five groups: control group ( C), cryopreservation group (Ⅰ), ischemic preconditioning group (IP), atorvastatin (30 γμmol/L) treatment group (A30) and atorvastatin (100 μmol/L) treatment group (A100). In control group, normal donor livers were flushed with 4 ℃ UW solution. In group I, donor livers were cryopreserved for 8 h after UWs flushing. In group IP, donor livers were subjected to ischemic preconditioning, and then flushed and cryopreserved in UWs. In group A30, donor livers were treated as in group I except that 30 μmol/L atorvastatin was added to the UWs. In group A100, donor lovers were treated as in group I with the exception that 100 μmol/L atorvastatin was added to the UWs. The activity of HMGCR was assessed. Results HMGCR activity in the donor cantly increased after ischemic preconditioning[(3746±231 ) nmol/(min-mg)]. The enhanced HMGCR activity induced by ischemic preconditioning was inhibited by atorvastatin in a concentration-dependent mantivity by up-regulating its protein expression and this effect can be abrogated by atorvastatin.     

缺血预处理对肌皮瓣缺血再灌注损伤的保护作用

缺血预处理(Ischemicprecondition-ing,IP)对心肌保护作用的研究近年来取得较大的进展,其对骨骼肌的保护作用也已有实验证实,但其作用机制仍不清楚[1]。本研究以家猪岛状背阔肌肌皮瓣为实验模型,进一步验证缺血预处理对骨骼肌肌皮瓣的保护作用,并对其保护机制进行初步探讨。材料与方法一、实验动物模型及分组选用健康家猪16头,体重22.5～27kg,雌雄不拘,随机等分成2组,参照Mounsey[2]方法,设计切取以胸背动脉血管束为蒂的岛状背阔肌肌皮瓣(14cm×8cm),并将胸背神经及其分支切断以阻断其对肌肉反应的影响。将血管蒂向腋血管方向游离出足够的…     

常温下缺血预处理对肝细胞凋亡调节基因表达影响的实验研究

目的 探讨常温下大鼠肝脏缺血预处理对细胞凋亡调节基因C-jun和Bcl-X_L的表达及其对肝细胞的保护作用。方法 将30只Wistar大鼠随机分成假手术组(S组,10只)、缺血再灌注组(IR组,10只)、缺血预处理组(IP组,10只)。S组在游离肝蒂后、IR组和IP组在再灌30 min后0、1、3、6、20 h点采集肝组织标本切片行肝细胞凋亡,C-jun和BcI-X_L基因表达及形态学改变等检测。各组均在3、6、20 h点采集血标本检测肝损害标记酶(ALT、AST、LDH)。结果 ALT、AST及LDH值各时间点IR组和IP组均明显高于S组(P<0.01),IP组明显低于IR组(P<0.01)。IR组和IP组与S组比较,细胞凋亡指数(AI)有显著性增加(P<0.01),IP组与IR组比较,AI明显减少(P<0.01)。C-jun基因在S组和IP组各时间点表达不明显;在IR组表达明显,3h点达高峰,并持续至6h点。Bcl-X_L基因在S组、IR组各时间点表达不明显,在IP组3、6、20h点表达明显(P<0.05或P<0.01)。形态学研究显示,IR组有肝组织大片坏死及不可逆超微结构损害;IP组未见明显肝细胞坏死,且超微结构损害为可逆性。结论 ①缺血预处理通过调节肝细胞凋亡调节基因C-jun和Bcl-X_L的表达,发挥其对大鼠常温下肝脏缺血再灌注损伤的保护作用;②IR损伤可能通过激活凋亡诱导基因C-jun表达而促发大鼠肝细胞的过度凋亡;③IP可能通     

缺血预处理-后处理对大鼠肠缺血再灌注损伤的影响

目的 评价缺血预处理.后处理对大鼠肠缺血再灌注损伤的影响.方法 清洁级成年雄性SD大鼠40只.体重225～275 g,随机分为5组(n=8):假手术组(S组)仅分离肠系膜上动脉(SMA),不夹闭;肠缺血再灌注组(IIR组)采用夹闭SMA 60 min,再灌注60 min的方法制备肠缺血再灌注损伤模型;缺血预处理组(IPr组)夹闭SMA 10 min,再灌注10 min,余同IIR组;缺血后处理组(IPo 组)夹闭SMA 60 min后,再灌注30 s,缺血30 s,反复3次,再灌注60 min;缺血预处理.后处理组(IPr-IPo组)先行缺血预处理,再行缺血后处理,操作过程同IPr组和IPo组.于再灌注60 min时各组取肠粘膜组织,观察肠粘膜形态并行Chiu评分,检测丙二醛(MDA)含量,超氧化物歧化酶(SOD)及髓过氧化物酶(MPO)活性,同时采集动脉血样检测血浆肿瘤坏死因子α(TNF-α)及白细胞介素6(IL-6)浓度.结果 与S组比较,其余各组Chiu评分、MDA含量、MPO活性、血浆TNF-α与IL-6浓度升高,SOD活性降低(P<0.05).与IIR组比较,IPr组、IPo组及IPr-IPo组Chiu评分、MDA含量、MPO活性、血浆TNF-α和IL-6浓度降低.SOD活性升高(P<0.01).与IPr组和IPo组比较,IPr-IPo组Chiu评分和MDA含量降低,SOD活性升高(P<0.05).IPr组与IPo组各指标比较差异无统计学意义(P>0.05).结论 缺血预处理-后处理可减轻大鼠肠缺血再灌注损伤,较单独应用时效果好.     

缺血预处理对肺缺血再灌注损伤中细胞因子生成的影响

目的　探讨缺血预处理 (IPC)对肺缺血再灌注 (I/R)损伤的保护作用及其对细胞因子生成的影响。　方法　 36只大白兔分为 3组 :对照组、I/R组和IPC组。通过阻断左肺门造成兔在体I/R损伤 ,观察IPC对肺I/R损伤的保护作用 ,指标为肺组织湿干重比、肺通透性指数及支气管肺泡灌洗液(BALF)中白细胞分类计数 ;以双抗体夹心酶联免疫吸附试验法检测血清中肿瘤坏死因子α(TNFα)、白细胞介素 6(IL 6)、白细胞介素 8(IL 8)的含量。　结果　肺I/R损伤后 ,I/R组肺组织湿干重比、肺通透性指数及BALF中性粒细胞百分比分别为 9 73± 1 1 4、(41 62± 5 77)× 1 0 - 4和 (58 1± 1 0 0 ) % ;IPC组分别为 6 2 3± 0 69、(2 0 31± 4 0 3)× 1 0 - 4和 (2 3 8± 5 2 ) % ,两组差异有极显著意义 (P <0 0 1 )。I/R组血清TNFα、IL 6和IL 8含量分别为 (0 90 78± 0 1 0 6 2 )、(0 2 1 3 7± 0 0 598)和 (0 72 1 1± 0 0 979)ng/ml,IPC组分别为 (0 7478± 0 0 843)、(0 1 2 71± 0 0 0 89)和 (0 590 3± 0 0 746)ng/ml,较I/R组显著降低 (P <0 0 1 )。　结论　IPC对I/R损伤有显著的保护作用 ,机理可能与其抑制炎性细胞因子TNFα、IL 6和IL 8的合成和释放 ,从而减轻中性粒细胞的浸润与激活有关。     

肢体缺血预处理对兔肺缺血再灌注损伤的影响

目的 探讨肢体缺血预处理对兔肺缺血再灌注损伤的影响.方法 健康日本大耳白兔18只,体重2.0～2.5 kg,雌雄不拘,随机分为3组(n=6):假手术组(S组)开胸后左侧肺门穿线但不结扎,旷置观察340 min;缺血再灌注组(IR组)开胸旷置100 min,阻断左侧肺门,左肺不张后60 min再灌注180 min;肢体缺血预处理组(L组)捆绑双后肢10 min,松开10 min,反复3次后恢复灌注,60 min后阻断左侧肺门60 min,再灌注180 min.于缺血前、再灌注15、30、60、120、180 min时采集左颈内动脉血样行血气分析,计算呼吸指数(R1);于再灌注180 min时处死动物,取左肺上叶组织,测定超氧化物歧化酶(SOD)、髓过氧化物酶(MPO)活性及丙二醛(MDA)含量,计算肺湿干重比(W/D);取左肺下叶行支气管肺泡灌洗,计算肺通透性指数;取左肺中叶组织,观察肺组织病理学,进行弥漫性肺泡损伤(DAD)评分.结果 与s组比较,IR组RI、MDA含量、MPO活性、肺W/D、肺通透性指数和DAD评分升高,SOD活性降低(P<0.05或0.01);与IR组比较,L组RI,MDA含量、MPO活性、肺W/D、肺通透性指数和DAD评分降低,SOD活性升高(P<0.05或0.01);L组和S组间上述指标比较差异无统计学意义(P>0.05).L组和S组肺组织病理损伤程度较IR组减轻.结论 肢体缺血预处理可减轻兔肺缺血再灌注损伤.     

缺血预处理-后处理对大鼠肠缺血再灌注损伤的影响

Objective To evaluate the effects of ischemic preconditioning-postconditioning on the intestinal ischemia-reperfusion (IR) injury in rats. Methods Forty healthy male SD weighing 225-275 g were randomly assigned into 5 groups ( n = 8 each): group I sham operation (group S) ; group II intestinal IR (group IIR); group Ⅲ ischemic preconditioning (group Ipr); group IV ischemic postconditioning (group Ipo); group V Ipr+ Ipo. The rats were anesthetized with intraperitonel 20% urethane 5 ml/kg. Superior mesenteric artery (SMA) was occluded for 60 min followed by 60 min reperfusion. In group S, SMA was isolated but not occluded. In group Ipr, SMA was occluded for 10 min followed by 10 min reperfusion, and the rest procedures were performed using the method described in group IIR. In group Ipo, 60 min ischemia was followed by three 30 s episodes of ischemia at 30 s intervals for reperfusion. In group Ipr+ Ipo, Ipr was performed followed by Ipo and the procedures were performed using the methods described in group Ipr and Ipo. The animals were killed at 60 min of reperfusion. The intestinal tissues were immediately removed for determination of MDA content, SOD and MPO activities and the degree of damage to intestinal mucous membrane was scored according to Chiu score. Arterial blood samples were taken for determination of plasma concentrations of TNF-α and 1L-6. Results Compared with group S, Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly increased, whereas SOD activity decreased in the other 4 groups ( P < 0.05). Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly decreased, whereas SOD activity increased in group Ipr, Ipo and Ipr + Ipo as compared with group IIR ( P < 0.05). Chiu score and MDA content were significantly lower, whereas SOD activity higher in group Ipr + Ipo than in group Ipr and Ipo ( P < 0.05). No significant differences were detected in the indices between group Ipr and group Ipo ( P > 0.05). Conclusion Ischemic preconditioning-postconditioning can attenuate the intestinal IR injury in rats, and the efficacy is better than that of either Ipr or Ipo alone.     

缺血预处理-后处理对大鼠肠缺血再灌注损伤的影响

Objective To evaluate the effects of ischemic preconditioning-postconditioning on the intestinal ischemia-reperfusion (IR) injury in rats. Methods Forty healthy male SD weighing 225-275 g were randomly assigned into 5 groups ( n = 8 each): group I sham operation (group S) ; group II intestinal IR (group IIR); group Ⅲ ischemic preconditioning (group Ipr); group IV ischemic postconditioning (group Ipo); group V Ipr+ Ipo. The rats were anesthetized with intraperitonel 20% urethane 5 ml/kg. Superior mesenteric artery (SMA) was occluded for 60 min followed by 60 min reperfusion. In group S, SMA was isolated but not occluded. In group Ipr, SMA was occluded for 10 min followed by 10 min reperfusion, and the rest procedures were performed using the method described in group IIR. In group Ipo, 60 min ischemia was followed by three 30 s episodes of ischemia at 30 s intervals for reperfusion. In group Ipr+ Ipo, Ipr was performed followed by Ipo and the procedures were performed using the methods described in group Ipr and Ipo. The animals were killed at 60 min of reperfusion. The intestinal tissues were immediately removed for determination of MDA content, SOD and MPO activities and the degree of damage to intestinal mucous membrane was scored according to Chiu score. Arterial blood samples were taken for determination of plasma concentrations of TNF-α and 1L-6. Results Compared with group S, Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly increased, whereas SOD activity decreased in the other 4 groups ( P < 0.05). Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly decreased, whereas SOD activity increased in group Ipr, Ipo and Ipr + Ipo as compared with group IIR ( P < 0.05). Chiu score and MDA content were significantly lower, whereas SOD activity higher in group Ipr + Ipo than in group Ipr and Ipo ( P < 0.05). No significant differences were detected in the indices between group Ipr and group Ipo ( P > 0.05). Conclusion Ischemic preconditioning-postconditioning can attenuate the intestinal IR injury in rats, and the efficacy is better than that of either Ipr or Ipo alone.     

缺血预处理-后处理对大鼠肠缺血再灌注损伤的影响

Objective To evaluate the effects of ischemic preconditioning-postconditioning on the intestinal ischemia-reperfusion (IR) injury in rats. Methods Forty healthy male SD weighing 225-275 g were randomly assigned into 5 groups ( n = 8 each): group I sham operation (group S) ; group II intestinal IR (group IIR); group Ⅲ ischemic preconditioning (group Ipr); group IV ischemic postconditioning (group Ipo); group V Ipr+ Ipo. The rats were anesthetized with intraperitonel 20% urethane 5 ml/kg. Superior mesenteric artery (SMA) was occluded for 60 min followed by 60 min reperfusion. In group S, SMA was isolated but not occluded. In group Ipr, SMA was occluded for 10 min followed by 10 min reperfusion, and the rest procedures were performed using the method described in group IIR. In group Ipo, 60 min ischemia was followed by three 30 s episodes of ischemia at 30 s intervals for reperfusion. In group Ipr+ Ipo, Ipr was performed followed by Ipo and the procedures were performed using the methods described in group Ipr and Ipo. The animals were killed at 60 min of reperfusion. The intestinal tissues were immediately removed for determination of MDA content, SOD and MPO activities and the degree of damage to intestinal mucous membrane was scored according to Chiu score. Arterial blood samples were taken for determination of plasma concentrations of TNF-α and 1L-6. Results Compared with group S, Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly increased, whereas SOD activity decreased in the other 4 groups ( P < 0.05). Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly decreased, whereas SOD activity increased in group Ipr, Ipo and Ipr + Ipo as compared with group IIR ( P < 0.05). Chiu score and MDA content were significantly lower, whereas SOD activity higher in group Ipr + Ipo than in group Ipr and Ipo ( P < 0.05). No significant differences were detected in the indices between group Ipr and group Ipo ( P > 0.05). Conclusion Ischemic preconditioning-postconditioning can attenuate the intestinal IR injury in rats, and the efficacy is better than that of either Ipr or Ipo alone.     

不同时间的缺血预处理对肝脏缺血再灌注损伤的影响

我们通过观察不同时间的缺血预处理对肝脏缺血再灌注损伤的影响,旨在探讨ＰＣ对肝脏缺血再灌注损伤的保护作用所需要的适合的预处理时间。一、材料与方法１．动物模型：雄性ＳＤ大鼠６０只,体重１８０～２２０ｇ,参照Ｊａｅｓｃｈｋｅ和Ｍｅｔｚｇｅｒ法制备成右肝全部缺血、左肝部分缺血后再灌注大鼠模型［１］。２．预处理方案：本实验共设５组,每组１２只大鼠;假手术组（Ｓ组）：仅行假手术;缺血再灌注组（ＩＲ组）：肝脏持续缺血６０分钟,再灌注３０分钟;预处理组分为３组,在肝脏持续缺血之前分别进行５分钟缺血及５分钟的再灌…     

缺血预处理-后处理对大鼠肠缺血再灌注损伤的影响

Objective To evaluate the effects of ischemic preconditioning-postconditioning on the intestinal ischemia-reperfusion (IR) injury in rats. Methods Forty healthy male SD weighing 225-275 g were randomly assigned into 5 groups ( n = 8 each): group I sham operation (group S) ; group II intestinal IR (group IIR); group Ⅲ ischemic preconditioning (group Ipr); group IV ischemic postconditioning (group Ipo); group V Ipr+ Ipo. The rats were anesthetized with intraperitonel 20% urethane 5 ml/kg. Superior mesenteric artery (SMA) was occluded for 60 min followed by 60 min reperfusion. In group S, SMA was isolated but not occluded. In group Ipr, SMA was occluded for 10 min followed by 10 min reperfusion, and the rest procedures were performed using the method described in group IIR. In group Ipo, 60 min ischemia was followed by three 30 s episodes of ischemia at 30 s intervals for reperfusion. In group Ipr+ Ipo, Ipr was performed followed by Ipo and the procedures were performed using the methods described in group Ipr and Ipo. The animals were killed at 60 min of reperfusion. The intestinal tissues were immediately removed for determination of MDA content, SOD and MPO activities and the degree of damage to intestinal mucous membrane was scored according to Chiu score. Arterial blood samples were taken for determination of plasma concentrations of TNF-α and 1L-6. Results Compared with group S, Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly increased, whereas SOD activity decreased in the other 4 groups ( P < 0.05). Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly decreased, whereas SOD activity increased in group Ipr, Ipo and Ipr + Ipo as compared with group IIR ( P < 0.05). Chiu score and MDA content were significantly lower, whereas SOD activity higher in group Ipr + Ipo than in group Ipr and Ipo ( P < 0.05). No significant differences were detected in the indices between group Ipr and group Ipo ( P > 0.05). Conclusion Ischemic preconditioning-postconditioning can attenuate the intestinal IR injury in rats, and the efficacy is better than that of either Ipr or Ipo alone.     

缺血预处理-后处理对大鼠肠缺血再灌注损伤的影响

Objective To evaluate the effects of ischemic preconditioning-postconditioning on the intestinal ischemia-reperfusion (IR) injury in rats. Methods Forty healthy male SD weighing 225-275 g were randomly assigned into 5 groups ( n = 8 each): group I sham operation (group S) ; group II intestinal IR (group IIR); group Ⅲ ischemic preconditioning (group Ipr); group IV ischemic postconditioning (group Ipo); group V Ipr+ Ipo. The rats were anesthetized with intraperitonel 20% urethane 5 ml/kg. Superior mesenteric artery (SMA) was occluded for 60 min followed by 60 min reperfusion. In group S, SMA was isolated but not occluded. In group Ipr, SMA was occluded for 10 min followed by 10 min reperfusion, and the rest procedures were performed using the method described in group IIR. In group Ipo, 60 min ischemia was followed by three 30 s episodes of ischemia at 30 s intervals for reperfusion. In group Ipr+ Ipo, Ipr was performed followed by Ipo and the procedures were performed using the methods described in group Ipr and Ipo. The animals were killed at 60 min of reperfusion. The intestinal tissues were immediately removed for determination of MDA content, SOD and MPO activities and the degree of damage to intestinal mucous membrane was scored according to Chiu score. Arterial blood samples were taken for determination of plasma concentrations of TNF-α and 1L-6. Results Compared with group S, Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly increased, whereas SOD activity decreased in the other 4 groups ( P < 0.05). Chiu score, MDA content, MPO activity, and plasma concentrations of TNF-α and IL-6 were significantly decreased, whereas SOD activity increased in group Ipr, Ipo and Ipr + Ipo as compared with group IIR ( P < 0.05). Chiu score and MDA content were significantly lower, whereas SOD activity higher in group Ipr + Ipo than in group Ipr and Ipo ( P < 0.05). No significant differences were detected in the indices between group Ipr and group Ipo ( P > 0.05). Conclusion Ischemic preconditioning-postconditioning can attenuate the intestinal IR injury in rats, and the efficacy is better than that of either Ipr or Ipo alone.