中性粒细胞与心肌缺血/再灌注损伤

背景 现已明确,炎症过程是心肌缺血/再灌注损伤(ischemia/reperfusion injury,I/RI)最重要的致病因素之一,而中性粒细胞是炎症反应的核心介导者.针对中性粒细胞的这种致病作用,部分研究者提出了抗中性粒细胞治疗,但是治疗效果却不尽相同,甚至大相径庭.更有研究者指出,中性粒细胞在心肌I/RI中尚发挥着一定的有益作用.针对这种现状,我们在此将中性粒细胞与心肌I/RI作一综述. 目的 评价中性粒细胞在心肌I/RI致病机制中的作用,探索抗中性粒细胞治疗的方向.内容 包括中性粒细胞对心肌I/RI的致病作用,抗中性粒细胞治疗的现状及其当前存在矛盾之处. 趋向 通过全面理解中性粒细胞在心肌I/RI中的作用,为今后进行适度的抗中性粒细胞治疗提供参考,并为今后发展多靶向联合措施治疗心肌I/RI提供思路.     

芬太尼和舒芬太尼对左旋甲状腺素钠预处理大鼠心肌保护作用的影响

目的 评价芬太尼和舒芬太尼对左旋甲状腺素钠预处理大鼠心肌保护作用的影响.方法 幼鼠采用随机数字表法随机分为7组(每组8只):空白对照组(BC组)、对照组(C组)、左旋甲状腺素钠10 μg组(10 μg组)、芬太尼组(F组)、舒芬太尼组(S组)、芬太尼联合左旋甲状腺素钠组(F+L组)和舒芬太尼联合左旋甲状腺素钠组(S+L组).采用Langendorff装置建立离体心脏缺血/再灌注损伤(ischemia/reperfusion injury,I/RI)模型,F组和F+L组灌注液中芬太尼浓度为30 μg/L,S组和S+L组灌注液中舒芬太尼浓度为3 μg/L.结果 再灌注30 min时血流动力学F组和S组明显差于BC组;10 μg组、F+L组和S+L组优于C组、F组和S组.BC组、C组、10 μg组、F组、S组、F+L组和S+L组再灌注期的冠脉流量分别是(19±2)、(16±1)、(21±2)、(17±1)、(17±1)、(21±1)、(22±1)ml/min,并且10 μg组、F+L组和S+L组的冠脉流量高于C组、F组和S组.冠脉流出液中的肌酸激酶同工酶(creatine kinase,CK-MB)活性C组、F组和S组高于10 μg组、F+L组和S+L组.心肌热休克蛋白70(heatshock proteins70,HSP70)和肌球蛋白重链(myosin heavy-chain,MHC)α mRNA表达10 μg组、F+L组和S+L组明显强于C组、F组和S组.但是所有检测指标在10 μg组、F+L组和S+L组之间差异无统计学意义. 结论芬太尼和舒芬太尼对左旋甲状腺素钠预处理的心肌保护作用均无明显影响.     

迷走神经电刺激后处理对大鼠心肌缺血再灌注损伤的影响

目的 评价迷走神经电刺激后处理对大鼠心肌缺血再灌注损伤的影响.方法 雄性SD大鼠60只,体重250～350 g,采用随机数字表法,将其随机分为3组(n＝20):假手术组(S组)、缺血再灌注组(I/R组)和迷走神经电刺激后处理组(POES组).I/R组和POES组采用结扎左冠状动脉前降支30 min和再灌注120 min的方法制备心肌缺血再灌注损伤模型,S组仅穿线.POES组在心肌缺血15 min时对右侧迷走神经干实施电刺激30 min,电刺激参数:波宽2ms,频率10 Hz,电流强度随大鼠HR进行调整,以保持HR较刺激前降低10％.于缺血前(基础状态)、缺血1、10 min和再灌注30、60、120 min时记录HR和MAP,计算HR和MAP的乘积(RPP).各组随机取10只大鼠,于再灌注120 min时,采集颈动脉血样,采用ELISA法检测血清cTnI、CK-MB、TNF-α、高迁移率族蛋白1(HMGB1)、细胞间粘附分子1(ICAM-1)、IL-1、IL-6和IL-10的浓度;颈动脉采血后,采用伊文蓝和TTC双重染色法测定心肌梗死体积.再灌注120 min时,各组随机处死10只大鼠,取缺血区和非缺血区心肌组织,采用ELISA法检测TNF-α、HMGB1、ICAM-1、IL-1、IL-6和IL-10的含量.结果 与S组比较,I/R组缺血10 min和再灌注30 min时HR增快,缺血1min时MAP和RPP降低,心肌梗死体积、血清cTnI、CK-MB、TNF-α、HMGB1、ICAM-1、IL-1和IL-6的浓度、缺血区和非缺血区心肌组织TNF-α、HMGB1、ICAM-1、IL-1、IL-6和IL-10的含量升高;POES组缺血10 min时HR增快,血清TNF-α浓度降低,心肌梗死体积、血清cTnI、CK-MB、ICAM-1和IL-10的浓度、缺血区心肌组织ICAM-1、IL-1、IL-6和IL- 10的含量、非缺血区心肌组织HMGB1、ICAM-1、IL-1、IL-6和IL-10的含量升高(P<0.05);与I/R组比较,POES组HR、MAP和RPP差异无统计学意义(P＞0.05),心肌梗死体积、血清cTnI、CK-MB、TNF-α、HMGB1、ICAM-1、IL-1和IL-6的浓度、缺血区和非缺血区心肌组织TNF-α、HMGB1、ICAM-1、IL-1和IL-6的含量降低,IL- 10含量升高(P<0.05).结论 迷走神经电刺激后处理可减轻大鼠心肌缺血再灌注损伤,其机制与抑制局部和全身炎性反应有关.     

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.     

视频喉镜在气道管理中应用的进展

视频喉镜是能够提供上呼吸道间接视野的新型气管插管设备。在困难气道管理处理方面．与直接喉镜相比．视频喉镜能够改善声门显露的Cormack—Lehane分级,并能在较短时间内达到相同或更高的气管插管成功率。尽管视频喉镜可获得非常好的声门显露．但是应用视频喉镜时插入和推进气管导管有时可发生失败。到目前为止,尚无确切证据表明在正常或困难气道患者视频喉镜应取代直接喉镜。     

活性氧在芬太尼后处理和肢体远隔缺血后处理减轻大鼠心肌缺血再灌注损伤中的作用

目的 探讨活性氧在芬太尼后处理和肢体远隔缺血后处理减轻大鼠心肌缺血再灌注损伤中的作用.方法 成年雄性SD大鼠63只,8周龄,体重250 ～ 350 g,采用随机数字表法,将其随机分为7组(n=9):假手术组(S组)、心肌缺血再灌注组(I/R组)、芬太尼后处理组(F组)、肢体远隔缺血后处理组(R组)、活性氧清除剂N-(2-巯基丙酰基)-甘氨酸(MPG)组(M组)、MPG+芬太尼后处理组(MF组)和MPG+肢体远隔缺血后处理组(MR组).除S组外,其余6组采用结扎左冠状动脉前降支30 min再灌注180 min的方法制备心肌缺血再灌注损伤模型.在缺血前5 min至再灌注15 min M组、MF组和MR组静脉输注MPG 5 mg/kg,其他4组给予等容量生理盐水,心肌缺血15 min时,F组和MF组静脉注射芬太尼30 μg/kg;R组和MR组结扎大鼠双后肢造成缺血10 min.心肌再灌注180 min时,采集动脉血样,测定血清心肌肌钙蛋白Ⅰ(cTnI)浓度,然后处死大鼠,取心肌组织,采用TTC染色法测定心肌梗死体积.结果 与S组比较,其余6组血清cTnI浓度和心肌梗死体积均升高(P＜0.05);与I/R组比较,M组血清cTnI浓度和心肌梗死体积差异无统计学意义(P＞0.05),F组和R组血清cTnI浓度和心肌梗死体积降低(P＜ 0.05);MF组和F组血清cTnI浓度和心肌梗死体积差异无统计学意义(P ＞0.05); MR组血清cTnI浓度和心肌梗死体积高于R组(P＞0.05).结论 活性氧参与了肢体远隔缺血后处理减轻大鼠心肌缺血再灌注损伤的效应,而未参与芬太尼后处理的心肌保护作用.     

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.     

κ受体在芬太尼后处理和肢体远隔缺血后处理对大鼠心肌缺血-再灌注损伤保护效应中的作用

目的探讨κ受体在芬太尼后处理和肢体远隔缺血后处理(RIP)心肌保护作用机制中的作用。方法将72只成年雄性SD大鼠随机均分为四组:模型组、芬太尼后处理组、肢体RIP组、芬太尼后处理和肢体RIP联合应用组。全部大鼠在体结扎冠状动脉左前降支(LAD)30min和再灌注180min。在结扎LAD前5min,将每组再均分为A、B两个亚组,分别静脉输注生理盐水和κ受体拮抗剂nor-binaltorphimine(nor-BNI)。再灌注180min时,测定血浆肌酸激酶MB同工酶(CK-MB)活性和血清心肌肌钙蛋白I(cTnI)浓度,采用伊文氏蓝和氯化三苯基四氮唑染色法测定心肌梗死面积(IS)。结果芬太尼后处理和肢体RIP均可显著降低心肌缺血-再灌注后的IS以及血清CK-MB和cTnI(P<0.05),联合应用组心肌保护效果显著增强(P<0.05)。结论κ受体参与芬太尼后处理的心肌保护作用,但未参与肢体RIP的降低进行梗死面积的保护作用。κ受体对于联合应用芬太尼后处理和肢体RIP降低心肌梗死面积方面的协同作用十分重要。     

磷脂酰肌醇3激酶/丝苏氨酸蛋白激酶信号转导通路在芬太尼后处理和远隔缺血后处理心肌保护中的作用

目的 在心肌缺血/再灌注损伤(ischemia/reperfusion injury,I/RI)大鼠探讨磷脂酰肌醇3激酶/丝苏氨酸蛋白激酶(phosphoinositide 3 kinase/serine-threonine kinase,PI3K/Akt)信号转导通路在芬太尼后处理和远隔缺血后处理心肌保护中的作用.方法 将32只成年雄性SD大鼠(体重250g～350 g)麻醉后,采用计算机产生的随机数随机分为4组:对照组(C组)、芬太尼后处理组(F组)、肢体远隔缺血后处理组(R组)及联合应用芬太尼后处理和肢体远隔缺血后处理组(F-R组).在结扎大鼠冠状动脉左前降支(left anterior descending coronary artery,LAD)30 min造成局部心肌缺血后,开放心肌再灌注60 min建立大鼠心肌I/RI模型.采用SA Bioscience公司功能分类基因芯片和免疫蛋白印迹分析法检测再灌注60 min后缺血区心肌内与PI3K/Akt相关基因的表达和磷酸化Akt蛋白的表达情况.结果 利用基因芯片检测的与PI3K/Akt相关的基因中,与C组比较,F组共有9个基因的表达显著上调,而R组仅2个基因的表达显著上调;但F-R组共有33个基因的表达较C组显著上调.蛋白印记分析结果显示,与C组比较,F组、R组和F-R组心肌标本内磷酸化Akt蛋白表达量均增高;而与F组和R组比较,F-R组心肌标本内磷酸化Akt蛋白表达量进一步增高.结论 联合应用芬太尼后处理和肢体远隔缺血后处理可明显增强PI3K/Akt信号转导通路激活.     

两种不同培养基对体外培养脊髓神经元的影响

目的建立体外稳定获取大数量及高纯度脊髓神经元的培养方案,比较当前国内外最常用的无血清培养基（Neurobasal+B27,NCM）与传统含血清培养基（DMEM/F12+10%胎牛血清+5%马血清,SCM）对体外培养脊髓神经元生长状态的影响。方法取E14 15?d Wistar大鼠的胚胎脊髓组织行胰酶消化获取脊髓神经元的单细胞悬液,分别用NCM与SCM进行培养,差速贴壁法及Ara C干预纯化培养的神经元。于接种后第1、2、3、4、5、6、7?d倒置相差显微镜下观察细胞生长状态的变化,并用免疫荧光细胞化学法比较两种培养基培养下获取的神经元纯度。结果采用NCM培养的脊髓神经元生长良好,对环境变化如换液及加入Ara C更为耐受;NCM培养的神经元的纯度为(87.70±8.70)%,SCM培养的神经元纯度为（78.61±7.00）%,前者纯度更高（P=0.019）。结论NCM较之SCM更加适合脊髓神经元的体外培养。