【作者】 张素品；

【导师】 王国林；

【作者基本信息】 天津医科大学 ， 麻醉学， 2009， 博士

【摘要】 目的：目前肺缺血再灌注损伤仍然是困扰心胸外科手术的难题，有关其防治措施的研究尚未获得理想进展。麻醉药物的应用是围手术期的重要环节，已有研究发现卤族类吸入性麻醉剂预处理对肺缺血再灌注损伤具有保护作用，但仍有争议，有关其后处理作用的研究较少，所以深入研究常用卤族类吸入性麻醉剂对肺缺血再灌注损伤的影响具有重要的临床意义。本研究采用大鼠原位肺缺血再灌注损伤模型，探讨异氟烷、七氟烷预处理及后处理的肺保护作用，以期为临床合理选择麻醉药物提供理论依据，为麻醉药物脏器保护作用的深入研究开辟思路。方法：SPF级SD大鼠180只，随机分为6组(n=30)。①假手术组(C组)：开胸游离左肺门后，未予阻断；②缺血再灌注组(I／R组)：阻断左肺门45min，而后松开血管夹形成缺血再灌注；③异氟烷预处理组(ISO-Pre组)：持续吸入1MAC(1．4％)异氟烷30min后，阻断左肺门45min，然后松开血管夹形成再灌注；④异氟烷后处理组(IS0-Pos组)：阻断左肺门45min，在恢复灌注同时，以麻醉机吸入1MAC异氟烷30min；⑤七氟烷预处理组(SEV-Pre组)：阻断前吸入1MAC(2．1％)七氟烷30min；⑥七氟烷后处理组(SEV-Pos组)：在恢复灌注同时，以麻醉机吸入1MAC七氟烷30 min。各组均于再灌注0min、30min、60min、120min、240min共5个时点分别处死动物6只，留取动脉血、肺组织和肺泡灌洗液标本，测定动脉血氧分压，肺泡灌洗液中炎性细胞计数、中性粒细胞百分比和蛋白含量，肺组织髓过氧化酶、细胞因子TNF-α、IL-1、IL-6的浓度和细胞凋亡指数，肺泡灌洗液中细胞因子TNF-α、IL-1、IL-6和表面黏附分子CD11b、CD31、CD54和CD62L的表达变化；并行光镜、电镜观察肺组织病理形态学改变。结果：I／R组、ISO-Pre组、ISO-Pos组、SEV-Pre组和SEV-Pos组均随着再灌注时间的延长表现出明显的肺损伤变化，动脉血氧分压下降，肺组织MPO，TNF-α、IL-1、IL-6，细胞凋亡指数，以及肺泡灌洗液中炎性细胞计数、中性粒细胞百分比和蛋白含量均明显增高，INF-α、IL-1、IL-6和表面黏附分子CD11b、CD31、CD54和CD62L的表达增加。与C组、I／R组相比，异氟烷组和七氟烷组各项观察指标在不同时间点均存在统计学差异。异氟烷组和七氟烷组相比无显著差异。病理切片显示，I／R组肺泡和肺间质内白细胞聚集成团，肺泡结构破坏，间隔增宽，肺泡腔严重出血水肿，肺损伤较异氟烷组和七氟烷组更加严重。透射电镜也显示I／R组Ⅱ型肺泡上皮细胞板层小体空泡化，线粒体结构破坏，其改变与异氟烷组和七氟烷组存在差异。结论：卤族类常用吸入性麻醉剂—异氟烷、七氟烷预处理和后处理均能减轻大鼠肺缺血再灌注损伤，具有明确的肺保护作用。其对再灌注后肺组织损伤的保护作用可能是通过抑制炎症反应，减少中性粒细胞的浸润、粘附与迁移，降低肺组织细胞因子TNF-α、IL-1、IL-6的表达与释放，下调肺缺血再灌注损伤所致黏附分子CD11b、CD31、CD54、CD62L等的表达，进而减少PMN在肺内炎症部位的聚集，降低肺组织的通透性，减少肺组织细胞-特别是肺泡Ⅱ型上皮细胞的凋亡而实现的。不同的卤族类吸入性麻醉剂—异氟烷与七氟烷，不同的处理时机—即预处理与后处理，其所产生的对肺缺血再灌注损伤的保护作用大致相似，推测可能是通过相似甚或相同的作用机制发挥肺保护作用。更多还原

【Abstract】 Objective:With the developed cardiopulmonary surgical techniques,lung ischemiareperfusion injury (LIRI)still is a hard work.While clinical preventing researcheshaven’t got ideal progressions now.Administrating anesthetics during surgery is animportant element,some researches have found that the chlorine group inhalationanesthetics preconditioning have protective effects for LIRI.But there are somedifferent opinions,and the anesthetics postconditioning research is rare in theliterature.So it is important to performing more researches on the effects of inhalationanesthetics to LIRI.By setting the rat model of LIRI and administrating sevofluraneor isoflurane before and after ischemia,we try to compare the protective effects ofthem,and further reveal the possible mechanisms of these methods,so as to providetheoretical evidences for the corrective selection of anesthetics in clinical anesthesiaand surgery,and develop a new routine for organ protection.Method:180 healthy SD rats were randomly divided into 6 groups (n=6).①Shamgroup (C group):the left pulmonary hilum was dissociated after thoracotomy withoutocclusion and mechanically ventilated to the end;②Ischemia Reperfusion group (I/Rgroup):the left pulmonary hilum was occluded for 45min and reperfused;③Isoflurane-Preconditioning group (ISO-Pre group):administing 1MAC isoflurane(1.4%)30min before occlusion,others similar to I/R group;④Isoflurane-Postconditioning group (ISO-Pos group):administing 1MAC isoflurane30min accompanied by reperfusion;⑤Sevoflurane-Preconditioning group (SEV-Pregroup):administing 1MAC sevoflurane (2.1%)30min before the occlusion;⑥Sevoflurane-Postconditioning group (SEV-Pos group):administing 1MACsevoflurane 30min accompanied by reperfusion.At the end of experiment,each groupsacrifice 6 rats at reperfused 0min、30min、60min、120min、240min respectively,thenget arterial blood,lung tissue and bronchoalveolar lavage fluid (BALF)samples.Theparameters include artery blood oxygen pressure,amount of protein,white bloodcell differential counts,expression of tumor necrosis factors a (TNF-α),interleukin(IL-1),and IL-6 in BALF,the activity of myeloperoxidase (MPO)and theexpression of TNF-α,IL-1,and IL-6 in lung tissures,the expression of adhesion molecules CD11b,CD31,CD54,CD62L were detected.Apoptotic index wasmeasured by TUNEL assay.Using light microscope and electron microscopeinvestigate pathological changes of lung.Results:With the increasing of reperfusion stage,all test groups show apparent lunginjury changes,arterial blood oxygen pressure decreasing,the expression of MPO,TNF-α,IL-1,IL-6,and amount of protein,white blood cell differential countincreasing apparently.the expression of TNF-α,IL-1,IL-6,and adhesion moleculesCD1 lb,CD31,CD54,CD62L in BALF increasing also.Comparing with I/R groupand C group,there are apparent statistic variances in ISO and SEV groups.In I/Rgroup,significant membrane damages of typeⅡalveolar epithelial cell,vacuolization of amellar body,and disorganization of mitochondrion were revealedby electron microscope examination.While pathological changes were slight in ISOand SEV groups.There are integrated cell membrane and no vacuolization of lamellarbody.However,there are no differences between preconditioning andpostconditioning groups.Conclusion:As commonly used inhalation anesthetics,isoflurane and sevofluranepreconditioning or postconditioning all show protective effects for the LIRI in rats.The possible protective mechanisms include inhibiting inflammatory reaction,decreasing PMN infiltration and adhesion,down-regulating expression ofinflammatory factors TNF-α,IL-1,IL-6,and adhesion molecules CD11b,CD31,CD54,CD62L in BALF,so as to alleviating systemic and local inflammatory reaction,decreasing PMN aggregation and permeability of lung.There are similar protectiveeffects between ISO and SEV groups.So we interfere that they may share the samemechanisms to develop the protective effects.更多还原