盐酸戊乙奎醚对肢体缺血再灌注大鼠肾脏的保护作用

目的 探讨盐酸戊乙奎醚后处理对肢体缺血再灌注后肾脏的保护作用及其机制.方法 健康成年雄性Wistar大鼠72只,体重220～250 g,随机数字表法分为3组:对照组(C组)、肢体缺血再灌注组(I/R组)、盐酸戊乙奎醚后处理组(P组),根据缺血后再灌注时间点各组又分为缺血3 h(T0)、再灌注1 h(T1)、3 h(T2)、6 h(T3)四个亚组(n=6).除C组外,各组在大鼠双后肢根部用橡皮筋结扎,完全阻断血流3 h.P组在再灌注前3 min尾静脉注射盐酸戊乙奎醚0.15 mg/kg(0.8ml).比色法检测血清肌酐(Cr)和尿素氮(BUN)的含量、肾脏组织超氧化物歧化酶(SOD)的活性及丙二醛(MDA)的含量,酶联免疫吸附法测定血清肿瘤坏死因子α(TNF-α)的含量,免疫组织化学SABC法测定肾脏组织中缺氧诱导因子1α(HIF-1α)的表达,光镜下观察肾脏组织的病理学改变.结果 I/R组和P组血清BUN、Cr水平、SOD的活性、MDA水平、TNF-α水平、HIF-1α的表达均高于C组(均P<0.05);P组血清BUN、Cr、MDA、TNF-α水平及、HIF-1α表达均低于I/R组[T2时间点:(15.10 ±1.88)mmol/L比(19.46±2.76)mmol/L、(113±10)μmol/L比(143±11)μmol/L、(13.8 ±1.7)nmol/g比(15.5±1.8)nmol/g、(53.1±3.1)ng/L比(53.9±4.8)ng/L、0.298±0.015比0.471±0.032,均P<0.05],SOD的活性高于I/R组(P<0.05).结论 盐酸戊乙奎醚后处理可以下调HIF-1α的表达,减轻肢体缺血再灌注后肾脏的损伤.其机制可能是抑制了炎症反应及氧自由基的释放,改善了肾脏组织的缺血、缺氧状态.

Abstract：

Objective To evaluate the protection of penehyclidine hydrochloric postconditioning on HIF-1α (hypoxia-inducible factor -1α) in renal tissue injury induced by lower limb ischemia/reperfusion (I/R). Methods A total of 72 adult male Wistar rats weighing 230 - 250 g were randomly divided into 3 groups: control ( group C ) , limb ischemia-reperfusion ( group R/I) and penehyclidine hydrochloride postconditioning (group P). The animals were anesthetized by inhaling 2% isoflurane and blood flow of bilateral lower limbs was blocked with rubber bands for 3 h in groups P and R/I. In group P, penehyclidine hydrochloride 0. 15 mg/kg was injected via caudal vein at 3 min pre-reperfusion. After sacrificing, their kidneys were removed at 3 h of ischemia and 1, 3, 6 h of reperfusion respectively. The blood urea nitrogen (BUN) and creatinine ( Cr) were detected by colorimetric method, plasma tumor necrosis factor-α (TNF-α) by ELISA ( enzyme-linked immunosorbent assay ) and HIF-1α of renal tissue by immunohistochemistry. Renal pathological changes were observed under light microscope. Results Compared with group C, the serum levels of BUN and Cr increased while TNF-α and HIF-1α were upregulated in groups I/R and P (P < 0. 05). As compared with group I/R, the serum levels of BUN, Cr and MDA decreased while TNF-α and HIF-lα were down-regulated in group P . [at T2: (15. 10 ± 1. 88) mmol/L vs(19.46±2. 76) mmol/L, (113 ±10) μmol/L vs(143 ± 11) μmol/L, (13. 8 ±1.7) nmol/g vs (15.5 ±1.8) nmol/g, (53.1 ±3. 1)ng/L vs(53.9 ±4. 8) ng/L, 0.298 ±0.015 vs 0.471 ±0.032, all P<0.05 ]. Conclusion Penehyclidine hydrochloride can down-regulate the expression of HIF-lα and attenuate the renal injury induced by lower limb I/R. And the mechanisms may be through inhibiting the inflammatory reactions, reducing the release of oxygen free radicals and improving the conditions of hypoxia and ischemia.     

盐酸戊乙奎醚对心肌缺血再灌注损伤的保护作用

目的探讨盐酸戊乙奎醚预处理对心肌的保护作用。方法雄性SD大鼠24只,麻醉后取其心肌建立Langendorff灌流模型后,随机分为缺血再灌注对照组(心脏平衡60min,37℃缺血45min,复灌2h)、盐酸戊乙奎醚预处理实验1组和实验2组(心脏平衡20min,分别给予含0.1%和0.2%盐酸戊乙奎醚的灌注液预处理20min,洗脱20min,37℃缺血45min,复灌2h)等3组。测定LVDEP(左室舒张末压),LVDP(左室发展压)和±dp/dtmax(等容收缩期左心室内压力上升和下降的最大速率);平衡20min和复灌60min时测定冠脉流出液中磷酸肌酸激酶同工酶(CK)的含量。复灌结束后测定心梗面积。结果LVDEP,LVDP和±dp/dtmax基础值三组无显著性差异。复灌注后实验1组和实验2组LVDEP,LVDP和±dp/dtmax的恢复百分比,要好于对照组,有统计学差异,冠脉流出液中CK的含量和心梗面积低于对照组,有统计学差异,而实验1组和实验2组间多指标无统计学差异。结论盐酸戊乙奎醚预处理能改善心脏机械功能,减少CK的释放,并缩小心梗面积。     

肢体缺血再灌注损伤防治的研究现状

肢体缺血是临床常见的病理征象,尽管恢复其血液循环是肢体所必须的,但是再灌注又可能加重缺血组织的损伤,谓缺血再灌注损伤[1].近年来对肢体缺血再灌注损伤防治方面的研究取得了一定的进展,并且有些方法已应用于临床,疗效肯定.现综述如下.     

盐酸戊乙奎醚对大鼠心肌缺血/再灌注损伤血流动力学的影响

目的研究盐酸戊乙奎醚(PHC)对大鼠心肌缺血/再灌注(I/R)损伤血流动力学的影响。方法建立SD大鼠急性心肌I/R损伤模型,随机分为假手术(Sham)组、缺血/再灌注(I/R)组、PHC1(0.023 mg.kg-1)组、PHC2(0.070 mg.kg-1)组、PHC3(0.200 mg.kg-1)组、山莨菪碱15 mg.kg-1(Ani)组。大鼠缺血10 min再灌注15 min后测定血流动力学指标,包括标准Ⅱ导联心电图、收缩压(SP)、舒张压(DP)、心率(HR)、左室内压最大上升及下降速率(±dp/dt max)。结果I/R组大鼠心电图J点显著高于Sham组(P<0.01),PHC能剂量依赖性的降低J点(P<0.01);I/R组大鼠SP、DP、±dp/dt max低于Sham组(P<0.01),PHC各剂量组能不同程度提高SP、DP、±dp/dt max(P<0.05、P<0.01)。结论PHC对大鼠心肌I/R损伤血流动力学有改善作用。     

盐酸戊乙奎醚预处理对兔心肌缺血/再灌注损伤的保护作用

目的:探讨盐酸戊乙奎醚预处理对心肌缺血/再灌注损伤的保护作用.方法:24只新西兰兔随机分为3组(n=8),心肌缺血/再灌注对照组(C),山莨菪碱预处理组(A)和盐酸戊乙奎醚预处理组(P).每组兔均接受左冠脉前降支阻断60 min和再灌注180 min.取心肌组织进行电镜下超微结构观察.用氯化硝基四氮唑蓝法测定心肌梗死面积.结果:A组和P组心肌梗死面积较C组明显减少,而P组和A组之间比较没有显著差异;电子显微镜检查显示,C组线粒体水肿、损伤明显,而A组和P组线粒体损伤较轻.结论:盐酸戊乙奎醚预处理和山莨菪碱同样对兔心肌缺血/再灌注损伤有保护作用.     

盐酸戊乙奎醚对脑缺血再灌注损伤大鼠脑梗死体积和行为学的影响

目的 探讨选择性M胆碱受体阻滞剂（盐酸戊乙奎醚）对脑缺血再灌注损伤大鼠脑梗死体积和行为学变化的影响.方法 雄性SD大鼠随机分为假手术组、缺血再灌注组、东莨菪碱组和盐酸戊乙奎醚组.参照文献建立三动脉阻断法全脑缺血模型,缺血前40 min分别腹腔注射生理盐水（1 ml）、东莨菪碱（0.01 mg/kg）和盐酸戊乙奎醚（0.01 mg/kg）.分别于脑缺血再灌注后1天、3天和7天用开阔法、平衡木法、攀绳和肌力试验测定其行为学指标,并取脑测定梗死体积.结果 大鼠缺血再灌注后出现行为学异常,前脑散在梗死灶,但早期3组之间无明显差别.再灌注3天和7天,与缺血再灌注组比较,盐酸戊乙奎醚组和东莨菪碱组脑梗死体积较小,行为学指标改善.盐酸戊乙奎醚组较东莨菪碱组改善更加明显.结论 盐酸戊乙奎醚能减少脑缺血再灌注损伤大鼠脑梗死体积的进一步扩大并且改善其行为学指标,此作用优于同等剂量的东莨菪碱.     

肢体缺血再灌注损伤的研究进展

缺血再灌注损伤的基础研究取得了明显的进展,这亦反映在对肢体缺血再灌注损伤的研究中。本文仅就后者的发生机制,对局部和全身的影响以及对其防治等方面的若干进展进行介绍和展望。     

肢体缺血再灌注损伤的研究进展

各种原因造成的肢体缺血是一种常见的临床征象，恢复充足的血液供应乃缺血组织成活之关键，但是缺血组织再灌注又可导致缺血组织的进一步损伤，此称为缺血再灌注损伤。如果缺血组织的范围较广泛，如腹主动脉瘤手术、主要的血管栓塞或损伤、高位肢体离断、严重肢体挤压伤及长时间应用止血带等，再灌注损伤不仅存在于缺血组织，尚可进一步引发远隔器官的损伤，进一步发展时可衍变成全身炎性反应综合征（SIRS），甚至多器官功能不全综合征（MODS），可见，缺血再灌注损伤可能超过缺血局部，波及远处的非缺血器官。因此肢体缺血一再灌注损伤引发多器官功能衰竭的机制一直是重症医学领域的重大课题。本文结合国内外研究就此内容简要综述。     

肢体缺血再灌注损伤研究现状

一、缺血一再灌注损伤理论的提出过去学者们对肢体缺血的研究,主要集中在对肌肉缺血的研究上。临床上解决缺血的问题主要是尽早恢复血液供应,但却未注意当缺血的组织恢复血循环     

肢体急性动脉缺血再通术后再灌注损伤的防治

目的 探讨急性肢体动脉缺血再通术后再灌注损伤的有效治疗方法.方法 回顾性分析65例急性肢体动脉缺血再通术后再灌注损伤治疗患者的临床资料,上肢8例,下肢52例.结果 65例急性肢体动脉缺血再通术后出现再灌注损伤38例.肢体急性动脉栓塞再通术后再灌注损伤程度较动脉硬化闭塞症继发急性血栓形成重,再通术后再灌注损伤程度与术前缺血时间及缺血程度成正比关系.动脉再通后30min出现再灌注损伤,24h达到高峰,72h后开始缓解,时间8～15d.肌筋膜切开3例,死亡2例,药物治愈33例.结论 及时实施再通术是预防再灌注损伤的关键,再通术前后的有效治疗能够有效缓解再灌注损伤的发生和减轻再灌注损伤的症状.     

联合应用缺血后处理、远隔缺血后处理和纳洛酮后处理对大鼠脑缺血-再灌注损伤的影响

目的 评价联合应用缺血后处理、远隔缺血后处理和纳洛酮后处理对大鼠局灶性脑缺血-再灌注损伤的影响.方法 将110只大鼠随机分为5组(n=22),通过阻塞右侧大脑中动脉90 min和再灌注24 h实施局灶性脑缺血.再灌注.Ⅰ组为对照组;Ⅱ组为缺血后处理组,再灌注开始时实施3次30 s的缺血和再灌注;Ⅲ组为远隔缺血后处理组,再灌注开始前实施5 min的右侧股动脉缺血;Ⅳ组为纳洛酮后处理组,再灌注开始时腹腔注射纳洛酮10 mg/kg;Ⅴ组为联合应用组.再灌注2 h和24 h时测定大鼠的神经功能障碍评分(NDS);再灌注24 h时,测定脑梗死区面积(n=10)、脑组织微管相关蛋白2(MAP2)表达(n=6)和脑组织血浆容量、血管直径和节段长度(n=6).结果 观察期所有时间点的心率和平均动脉压(MAP)组间比较差异均无统计学意义(均P＞0.05).再灌注24 h后,Ⅰ～Ⅴ组的缺血侧脑梗死面积与同侧大脑半球面积的比值(即脑梗死严重程度)分别是43%±6%、31%±4%、32%±5%、28%±6%和21%±7%.与Ⅰ组比较,Ⅱ～Ⅴ组的NDS和脑梗死严重程度均低(均P＜0.05),MAP2表达、血浆容量、血管直径和节段长度均高,但上述指标在Ⅱ组、Ⅲ组和Ⅵ组之间比较差异均无统计学意义(均P＞0.05).与Ⅰ组、Ⅱ组、Ⅲ组和Ⅳ组比较,Ⅴ组的NDS评分和脑梗死程度均低(均P＜0.05),MAP2表达和血浆容量显著高(均P＜0.05),但是缺血侧脑组织的血管直径和节段长度在Ⅱ组、Ⅲ组Ⅵ组和Ⅴ组之问差异均无统计学意义(均P＞0.05).结论 在局灶性脑缺血-再灌注损伤大鼠,缺血后处理、远隔缺血后处理和纳洛酮后处理均具有明显的神经保护作用,表现为脑梗死严重程度降低和神经功能障碍改善.联合应用3种后处理措施可获得增强的神经保护效应.

Abstract：

Objective To assess the effects of ischemic postconditioning, remote ischemic postconditioning and naloxone postconditioning on focal cerebral ischemia-reperfusion injury in rats.Methods A total of 110 adult SD rats were randomly divided into 5 groups (n =22 each). The focal cerebral ischemia-reperfusion injury was induced by a 90-minute occlusion of right middle cerebral artery (MCA) and a 24-hour reperfusion sequentially. Group 1 was of ischemia-reperfusion control; Group 2 ischemic postconditioning induced by three 30-second cycles of MCA occlusion followed by a 30-second reperfusion; Group 3 remote ischemic postconditioning performed via a transient occlusion of right femoralartery at 5 min before the initiatlon of reperfusion:Group 4 naloxone posteonditioning with naloxone 10 mg/kg intraperitoneaUy injected at the initiation of reperfusion;Group 5 combined ischemic,remote ischernic & naloxone postconditioning performed simultaneously in accordance with the methods used in Groups 2,3 & 4.The neumlogie deftcit scores(NDS)were obtained at 2 h & 24 h post-reperfusion.At 24 h post-reperfusion.the anesthetized rat was sacrificed by decapitation and the brain rapidly extracted to asseSS the size ofcerebral infaret(n=10),detect the cerebral expression of microtubule-associated protein2(MAP2)(n=6),measure the plasma volume of cerebral tissues and quantify the diameter and segment artery at 5 min before the initiation of reperfusion; Group 4 naloxone postconditioning with naloxone 10 mg/kg intraperitoneally injected at the initiation of reperfusion; Group 5 combined ischemic, remote ischemic & naloxone postconditioning performed simultaneously in accordance with the methods used in Groups 2, 3 & 4. The neurologic deficit scores ( NDS) were obtained at 2 h & 24 h post-reperfusion. At 24 h post-reperfusion, the anesthetized rat was sacrificed by decapitation and the brain rapidly extracted to assess the size of cerebral infarct (n = 10), detect the cerebral expression of microtubule-associated protein2 ( MAP2) (n =6) , measure the plasma volume of cerebral tissues and quantify the diameter and segment length of cerebral microvessel (n = 6 ). Results There were no significant differences in the heart rate (HR) and mean arterial pressure (MAP) among the above five groups at all observed time points (P ＞ 0. 05). At 24 h post-reperfusion, the percentage of ischemic cerebral infarct size was 43% ±6% , 31% ±4% , 32% ±5% , 28% ±6% & 21% ±7% in ipsilateral hemisphere area (i. e. , cerebral infarct severity)in Groups 1-5 respectively. Compared with Group 1, the levels of NDS and cerebral infarct severity significantly decreased at ischemic side in Groups 2-5 ( P ＜ 0. 05 ). And the cerebral expression of MAP2,plasma volume of cerebral tissues, diameter and segment length of cerebral microvessel significantly increased at the ischemic side (all P＜0. 05). However, there were no significant differences in the abovementioned parameters at ischemic side among Groups 2, 3 and 4 (all P ＞0. 05). The parameters of NDS,cerebral infarct severity, cerebral expression of MAP2 and plasma volume of cerebral tissues in the ischemic side significantly increased in Group 5 compared with Groups 1,2,3 and 4 (all P ＜ 0. 05). The diameter and segment length of cerebral microvessel at ischemic side were not different among Groups 2,3,4 and 5 (all P＞0. 05). Conclusion In focal cerebral ischemia-reperfusion rats, ischemic, remote ischemic and naloxone postconditioning may produce significant neuroprotective effects of reduced cerebral infarct severity and improved neurologic dysfunctions. A combination of three postconditioning approaches enhances the above neuroprotective effects.     

丙泊酚对大鼠心肌缺血后处理的作用

目的 探讨不同剂量丙泊酚缺血后处理对大鼠心肌缺血/再灌注损伤的作用.方法 制备大鼠心肌缺血/再灌注损伤模型,结扎冠状动脉左前降支60 min,再灌注120 min.随机分为假手术组(S组)、生理盐水对照组(C组)、丙泊酚1 mg/kg组(P1组)、丙泊酚2 mg/kg组(P2组)、丙泊酚5 mg/kg组(P3组),除S组其余各组所用药物均以生理盐水稀释至2.5 ml,于再灌注前3 min经股静脉匀速输注至再灌注后5 min,测定心肌危险区面积和梗死区面积;采用免疫组化方法 检测心肌组织Caspase-3的表达;应用流式细胞仪检测心肌细胞凋亡率;运用Western印迹方法 测定Akt磷酸化水平.结果 与C组[危险区面积(41.5±1.0)%,梗死区面积(45.5±1.0)%,Caspase-3表达5.87±0.29,心肌细胞凋亡率(26.8±1.3)%,Akt磷酸化(10.8±1.9)%]相比,P1组和P2组大鼠危险区面积和梗死区面积明显减小[危险区面积(38.3±1.0)%和(37.3±1.2)%;梗死区面积(33.8±1.2)%和(30.2±1.7)%,均P<0.05];Caspase-3表达降低(1.50±0.36和1.48±0.30,均P<0.05);心肌细胞凋亡率下降[(16.3±1.2)%和(16.5±1.0)%,均P<0.05];而Akt磷酸化水平明显升高[(68.7±4.0)%和(58.3±2.8)%,均P<0.05].结论 丙泊酚1 mg/kg和2 mg/kg通过促进Akt磷酸化发挥I-postC保护作用.     

肾缺血后处理对大鼠Kim-1表达的影响及对缺血再灌注损伤的保护作用

目的：探讨缺血后处理(ischemic postconditioning, IPO)对大鼠肾缺血再灌注损伤（ischemia reperfusion injury, IRI）的保护作用及与肾损伤分子1（kidney injury molecule-1, Kim-1）表达的关系,以及Kim-1能否作为敏感的标记物反映IPO早期的保护效果,为IPO应用于泌尿外科临床寻找早期、有效的监测指标。方法：雄性SD大鼠85只,体重240~300 g,缺血再灌注组（IRI）30只,缺血后处理组（IPO）30只,假手术组（Sham）25只。经腹正中切口切除大鼠右肾建立左侧孤立肾模型。IRI组夹闭左肾动脉45 min后开放,IPO组在IRI模型基础上,恢复血流前给予反复6次10 s供血-10 s缺血的后处理。各组于术后6 h、12 h、24 h、48 h、72 h每时点随机选取5只大鼠,分别取血和肾皮质标本。测定血尿素氮（BUN）、肌酐（Cr）水平,实时PCR（RT-PCR）检测肾组织Kim-1 mRNA表达量。IRI和IPO组各随机取5只大鼠,于0 h、6 h、12 h、24 h、48 h、72 h这6个时点取尿液样本,ELISA法检测尿Kim-1含量。肾病理组织切片观察3组间的差别。结果：ELISA检测显示,IRI与IPO组尿液Kim-1分子均在再灌注6 h开始上升,24 h达峰值,6 h、12 h、24 h、72 h各组间比较差异有统计学意义（P<0.05）。RT-PCR显示,Kim-1 mRNA于再灌注6 h开始上升,24 h达峰值,各时间点IRI组显著高于IPO组（P<0.05）,24 h后IPO组Kim-1 mRNA下降速度较快（P<0.05）。BUN、Cr于术后12 h明显上升,比Kim-1分子升高时间延后,24 h后IRI组较IPO组显著增高（P<0.05）。肾组织病理切片结果提示,12 h、24 h、48 h IPO组肾损伤较IRI组明显减轻。结论：IPO能减轻大鼠肾IRI,并可以降低IRI后肾Kim-1表达量。Kim-1作为急性肾损伤的标记物和保护因子之一,较其他指标可更早、更有效地反映IPO的保护作用。     

联合应用缺血后处理、远隔缺血后处理和纳洛酮后处理对大鼠脑缺血-再灌注损伤的影响

Objective To assess the effects of ischemic postconditioning, remote ischemic postconditioning and naloxone postconditioning on focal cerebral ischemia-reperfusion injury in rats.Methods A total of 110 adult SD rats were randomly divided into 5 groups (n =22 each). The focal cerebral ischemia-reperfusion injury was induced by a 90-minute occlusion of right middle cerebral artery (MCA) and a 24-hour reperfusion sequentially. Group 1 was of ischemia-reperfusion control; Group 2 ischemic postconditioning induced by three 30-second cycles of MCA occlusion followed by a 30-second reperfusion; Group 3 remote ischemic postconditioning performed via a transient occlusion of right femoralartery at 5 min before the initiatlon of reperfusion:Group 4 naloxone posteonditioning with naloxone 10 mg/kg intraperitoneaUy injected at the initiation of reperfusion;Group 5 combined ischemic,remote ischernic & naloxone postconditioning performed simultaneously in accordance with the methods used in Groups 2,3 & 4.The neumlogie deftcit scores(NDS)were obtained at 2 h & 24 h post-reperfusion.At 24 h post-reperfusion.the anesthetized rat was sacrificed by decapitation and the brain rapidly extracted to asseSS the size ofcerebral infaret(n=10),detect the cerebral expression of microtubule-associated protein2(MAP2)(n=6),measure the plasma volume of cerebral tissues and quantify the diameter and segment artery at 5 min before the initiation of reperfusion; Group 4 naloxone postconditioning with naloxone 10 mg/kg intraperitoneally injected at the initiation of reperfusion; Group 5 combined ischemic, remote ischemic & naloxone postconditioning performed simultaneously in accordance with the methods used in Groups 2, 3 & 4. The neurologic deficit scores ( NDS) were obtained at 2 h & 24 h post-reperfusion. At 24 h post-reperfusion, the anesthetized rat was sacrificed by decapitation and the brain rapidly extracted to assess the size of cerebral infarct (n = 10), detect the cerebral expression of microtubule-associated protein2 ( MAP2) (n =6) , measure the plasma volume of cerebral tissues and quantify the diameter and segment length of cerebral microvessel (n = 6 ). Results There were no significant differences in the heart rate (HR) and mean arterial pressure (MAP) among the above five groups at all observed time points (P ＞ 0. 05). At 24 h post-reperfusion, the percentage of ischemic cerebral infarct size was 43% ±6% , 31% ±4% , 32% ±5% , 28% ±6% & 21% ±7% in ipsilateral hemisphere area (i. e. , cerebral infarct severity)in Groups 1-5 respectively. Compared with Group 1, the levels of NDS and cerebral infarct severity significantly decreased at ischemic side in Groups 2-5 ( P ＜ 0. 05 ). And the cerebral expression of MAP2,plasma volume of cerebral tissues, diameter and segment length of cerebral microvessel significantly increased at the ischemic side (all P＜0. 05). However, there were no significant differences in the abovementioned parameters at ischemic side among Groups 2, 3 and 4 (all P ＞0. 05). The parameters of NDS,cerebral infarct severity, cerebral expression of MAP2 and plasma volume of cerebral tissues in the ischemic side significantly increased in Group 5 compared with Groups 1,2,3 and 4 (all P ＜ 0. 05). The diameter and segment length of cerebral microvessel at ischemic side were not different among Groups 2,3,4 and 5 (all P＞0. 05). Conclusion In focal cerebral ischemia-reperfusion rats, ischemic, remote ischemic and naloxone postconditioning may produce significant neuroprotective effects of reduced cerebral infarct severity and improved neurologic dysfunctions. A combination of three postconditioning approaches enhances the above neuroprotective effects.     

联合应用缺血后处理、远隔缺血后处理和纳洛酮后处理对大鼠脑缺血-再灌注损伤的影响

Objective To assess the effects of ischemic postconditioning, remote ischemic postconditioning and naloxone postconditioning on focal cerebral ischemia-reperfusion injury in rats.Methods A total of 110 adult SD rats were randomly divided into 5 groups (n =22 each). The focal cerebral ischemia-reperfusion injury was induced by a 90-minute occlusion of right middle cerebral artery (MCA) and a 24-hour reperfusion sequentially. Group 1 was of ischemia-reperfusion control; Group 2 ischemic postconditioning induced by three 30-second cycles of MCA occlusion followed by a 30-second reperfusion; Group 3 remote ischemic postconditioning performed via a transient occlusion of right femoralartery at 5 min before the initiatlon of reperfusion:Group 4 naloxone posteonditioning with naloxone 10 mg/kg intraperitoneaUy injected at the initiation of reperfusion;Group 5 combined ischemic,remote ischernic & naloxone postconditioning performed simultaneously in accordance with the methods used in Groups 2,3 & 4.The neumlogie deftcit scores(NDS)were obtained at 2 h & 24 h post-reperfusion.At 24 h post-reperfusion.the anesthetized rat was sacrificed by decapitation and the brain rapidly extracted to asseSS the size ofcerebral infaret(n=10),detect the cerebral expression of microtubule-associated protein2(MAP2)(n=6),measure the plasma volume of cerebral tissues and quantify the diameter and segment artery at 5 min before the initiation of reperfusion; Group 4 naloxone postconditioning with naloxone 10 mg/kg intraperitoneally injected at the initiation of reperfusion; Group 5 combined ischemic, remote ischemic & naloxone postconditioning performed simultaneously in accordance with the methods used in Groups 2, 3 & 4. The neurologic deficit scores ( NDS) were obtained at 2 h & 24 h post-reperfusion. At 24 h post-reperfusion, the anesthetized rat was sacrificed by decapitation and the brain rapidly extracted to assess the size of cerebral infarct (n = 10), detect the cerebral expression of microtubule-associated protein2 ( MAP2) (n =6) , measure the plasma volume of cerebral tissues and quantify the diameter and segment length of cerebral microvessel (n = 6 ). Results There were no significant differences in the heart rate (HR) and mean arterial pressure (MAP) among the above five groups at all observed time points (P ＞ 0. 05). At 24 h post-reperfusion, the percentage of ischemic cerebral infarct size was 43% ±6% , 31% ±4% , 32% ±5% , 28% ±6% & 21% ±7% in ipsilateral hemisphere area (i. e. , cerebral infarct severity)in Groups 1-5 respectively. Compared with Group 1, the levels of NDS and cerebral infarct severity significantly decreased at ischemic side in Groups 2-5 ( P ＜ 0. 05 ). And the cerebral expression of MAP2,plasma volume of cerebral tissues, diameter and segment length of cerebral microvessel significantly increased at the ischemic side (all P＜0. 05). However, there were no significant differences in the abovementioned parameters at ischemic side among Groups 2, 3 and 4 (all P ＞0. 05). The parameters of NDS,cerebral infarct severity, cerebral expression of MAP2 and plasma volume of cerebral tissues in the ischemic side significantly increased in Group 5 compared with Groups 1,2,3 and 4 (all P ＜ 0. 05). The diameter and segment length of cerebral microvessel at ischemic side were not different among Groups 2,3,4 and 5 (all P＞0. 05). Conclusion In focal cerebral ischemia-reperfusion rats, ischemic, remote ischemic and naloxone postconditioning may produce significant neuroprotective effects of reduced cerebral infarct severity and improved neurologic dysfunctions. A combination of three postconditioning approaches enhances the above neuroprotective effects.     

缺血后处理对大鼠后肢肌肉缺血再灌注损伤作用的实验研究

目的探讨不同方式缺血后处理对大鼠后肢肌肉缺血再灌注损伤的保护作用。方法取Wistar雄性大鼠54只,建立后肢肌肉缺血再灌注模型,实验分为3组,每组18只,每个时间点6只,A组为缺血再灌注组,B组为缺血再灌注前给予1 min灌注1 min缺血重复3次后继续再灌注组,C组为缺血再灌注前给予10 min灌注10 min缺血重复3次后继续再灌注组,分别检测各组在再灌注1 h、3 h、9 h血清中的乳酸脱氢酶(LDH)、细胞间黏附分子-1(ICAM-1)及肌肉组织中丙二醛(MDA)含量,比较上述指标的变化。结果 3组各项指标均升高,不同时点比较差异均有统计学意义(P<0.01)。B组除1h ICAM-1外,各时间点上述指标均明显低于A组(P<0.01),C组各时点各指标与A组比较差异无统计学意义(P>0.05)。结论短时间多次重复停灌复灌后处理可减轻实验大鼠后肢肌肉缺血再灌注损伤     

肢体缺血后处理对孕兔失血性休克急性肾损伤的保护及作用机制

目的：探讨肢体缺血后处理对孕兔失血性休克肾损伤的保护及可能的作用机制。方法：24只孕兔制成重度失血性休克模型,均游离双侧股动脉,随机分为假手术组（S组）、缺血再灌注组（IR组）、肢体缺血后处理组（LRIP组）（每组8只）。S组：游离双侧股动脉后无失血及输血;IR：孕兔股动脉放血使平均动脉压40 mmHg维持180 min后,1 h内匀速回输全部血液,使孕兔血压维持在MAP稳定在80 mmHg之上并平稳24 h;LRIP组：在急性失血性休克180 min后,给予夹闭双侧股动脉缺血30 s再灌注30 s共10次后（即缺血后处理）,再输血复苏至24 h。分别采用全自动生化分析仪测定血尿素氮（BUN）、血肌酐（Cr）水平,酶联免疫吸附试验（ELISA）法测定不同时点（0 h、8 h、16 h、24 h）血清TNF-α、IL-10的含量,免疫组化法检测肾组织中核因子κB（NF-κB）表达;RTPCR法检测肾组织内TNF-α、IL-10及iNOS mRNA的表达;HE染色观察肾脏病理学改变。结果：（1）与I/R组相比,LRIP组不同时点Cr、BUN浓度降低,血清TNF-α含量降低、IL-10含量升高,肾组织NF-κB表达减少（P均〈0.05）;（2）与S组比较,肾内TNF-α、IL-10、iNOS mRNA在I/R组、LRIP组表达均上调（P〈0.05或P〈0.01）,与I/R组相比,肾内TNF-α、iNOS mRNA表达在LRIP组下调,IL-10 mRNA表达上调（P〈0.05）;（3）S组肾脏未发生明显的病理改变,I/R组肾小管可见明显玻璃样改变和坏死,肾小管略扩张,肾小球和肾小管周围可见炎症细胞浸润,LRIP组肾脏组织结构正常,少量的炎症细胞浸润,肾小管上皮细胞相对完整,水肿减轻。结论：重复10次缺血30 s再灌注30 s的肢体后处理对肾脏有保护作用,其机制可能与抑制肾组织NF-κB转录、减少iNOS mRNA的表达、改善肾内炎症反应有关。     

缺血后处理的肺保护作用研究进展

缺血后处理是在缺血预处理基础上提出的新概念,因其对器官缺血一再灌注损伤具有良好的保护作用,且具有事后性及良好的临床可控性,故应用性强,目前已成为研究保护器官缺血一再灌注损伤方面的热点。但缺血后处理对肺保护作用的研究相对较少,确切机制及诱导时间窗等问题尚不清楚。本文就其发现与应用、保护机制、时间窗、发展与展望等研究新进展进行综述。     

缺血后处理对老年大鼠心肌缺血再灌注损伤的保护作用

目的观察缺血后处理对老年大鼠心肌细胞凋亡的影响,并探讨细胞凋亡与氧化损伤的关系。方法老年雄性Wistar大鼠90只,采用数字表法随机分成3组(n=30):老年假手术组(saline control,SC组)、老年缺血再灌注组(ischemia/reperfusion,I/R组)和老年缺血后处理组(ischemic postconditioning,IPC组)。制备缺血再灌注损伤和缺血后处理模型,分析检测老年大鼠心肌组织的细胞凋亡情况,测定再灌注末抽血离心测定血清超氧化物歧化酶(superoxide dismutase,SOD)活性及丙二醛(malonaldehyde,MDA)浓度。结果 I/R组心肌细胞凋亡指数平均为53.99±10.54,IPC组平均凋亡指数为45.51±8.81,差异有统计学意义(P<0.01);I/R组血清SOD活性平均为(277.70±29.55)U/m L,IPC组平均质量浓度为(303.72±25.25)U/m L,差异有统计学意义(P<0.05);I/R组血清MDA浓度平均为(25.02±2.35)μmol/L,IPC组平均为(22.54±2.64)μmol/L,差异有统计学意义(P<0.05)。结论缺血后处理能够抑制心肌再灌注损伤诱导的细胞凋亡,其机制之一可能与增强心肌细胞抗氧化能力,抑制再灌注所致氧化损伤有关。缺血后处理对老年缺血再灌注心肌具有一定的保护作用。