脊髓爆震伤动物模型的建立及早期药物干预作用的初步研究

第四军医大学硕士学位论文脊髓爆震伤动物模型的建立及早期药物干预作用的初步研究姓名：马云青申请学位级别：硕士专业：外科学（骨外）指导教师：罗卓荆20070501第四军医大学硕士学位论3缩略语表缩略语英文全称中文全称ASCIacutespinalcordinjury急性脊髓损伤MPmethylprednisolone甲基强的松龙RDXcyclotrimethylenetrinitramine黑索金炸药TNTtrinitrotoluene三硝基甲苯T-SEPstibia-somatosensoryevokedpotentials体感诱发电位MEPSmotorevokedpotentials运动诱发电位ATPAdenosineTriphosphate三磷酸腺苷MDAmalondialdhehyde丙二醛SODSuperOxidaseDimutase超氧化物歧化酶BSTbio-shocktubes生物激波管PSDposttraumaticstressdisorder创伤后应激障碍ETendothrlin内皮素TNFTumornecrosisfactor肿瘤坏死因子PGprostaglandin前列腺素TXA2thromboxaneA2血栓素A2NGFnervegrowthfactor神经生长因子NTFneurotrophicfactor神经营养因子第四军医大学硕士学位论4脊髓爆震伤动物模型的建立及早期药物干预作用的初步研究硕士研究生：马云青导师：罗卓荆教授（主任医师）第四军医大学西京医院骨科，西安710032中文摘要随着武器装备的现代化以及高科技战争条件下战略战术的转变，战场上爆炸冲击伤的数量明显增加。脊髓作为中枢神经系统一旦受损，轻者影响战斗力，重者导致截瘫甚至死亡，特别是脊髓截瘫患者伤后护理困难、费用高昂、极易罹患各类并发症，因此脊柱、脊髓战伤已经成为各国相关部门研究的热点。以往，中枢神经系统特别是脊柱、脊髓火器伤的研究重点集中在枪弹贯通伤，但是随着各国单兵保护装备的不断更新和恐怖主义活动的增加，单纯的枪弹贯通伤数量明显减少，而爆炸冲击伤明显增加。至今为止，国内尚没有脊柱脊髓爆震性损伤动物模型的相关报道，使脊髓爆震伤的损伤机制研究及战场救治工作的开展相对缓慢。本课题的目的是建立实验室条件下的脊髓爆震伤动物模型，最大限度的模拟野战条件下冲击波的致伤作用，对脊柱脊髓爆震性损伤的组织病理学变化特点进行观察分析，在此基础上初步探讨甲基强的松龙对脊髓爆震伤后继发性脊髓损伤的干预作用，以期为临床针对性治疗脊髓爆震伤提供理论依据。实验的第一部分是建立可控性脊髓爆震伤动物模型，选择黑索金军用炸药作为爆源，应用纸制外壳，排除弹片干扰造成的实验可重复性降低，对实验动物加以保护后，背部平肩胛下角平面的胸腰段脊柱暴露于爆源正下方，第四军医大学硕士学位论5电击引爆。通过测量不同爆距的爆炸参数以及实验动物致伤情况，选择适当的爆炸距离。实验中测量了1、2、4、8cm最终选择4cm爆距作为脊髓爆震伤动物模型的标准爆距。近距离（4cm）爆炸致伤后实验动物立即死亡，病理解剖可见伤口大片软组织撕脱，深部椎板断裂，肺脏淤血，胸部大血管破裂，4cm爆距伤后实验动物未见死亡，病理学观察：损伤段脊髓组织6h为急性脊髓损伤表现，脊髓水肿明显，神经元肿胀，24h后神经元出现不可逆性表现，细胞红染，尼氏小体消失，细胞核缩小，髓鞘板层结构松散甚至崩解，伤后3d出现脊髓明显坏死区。同时实验动物双侧后肢运动消失。实验第二部分初步研究了甲基强的松龙对急性脊髓爆震伤后脊髓组织和血清中Ca2+、MDA及SOD含量的影响。于伤后8h内给予甲强龙冲击治疗（30mg/kg）维持30min。分别于不同的时点取材,检测血清中的SOD、MDA及受伤段脊髓组织中的Ca2+、SOD和MDA，结果证实：1．致伤后损伤组损伤段脊髓组织内MDA和Ca2+浓度在6h内较对照组迅速增加，SOD浓度下降。6h后增加不明显。2．致伤后损伤组血清内MDA浓度在6h内较对照组迅速增加，SOD浓度下降，在随后的24h内MDA浓度升高不明显，SOD浓度继续缓慢下降。3．MP能明显降低血清和脊髓组织中MDA、Ca2+含量，提高SOD浓度，在一定程度上阻止了继发性脊髓损伤发展。关键词：脊髓，冲击伤，爆震伤，甲基强的松龙资助基金项目：全军“十一五”科技攻关资助项目（06G097）第四军医大学硕士学位论6EstablishmentofacontrollablespinalcordblastinjurymodelandresearchofdrugearlyadministrationCandidateformaster:MaYunqingSupervisor:Prof.LuoZhuojingDepartmentoforthopaedics,Xijinghospital,FourthMilitaryMedicalUniversity,Xi’an710032,ChinaAbstractWithmodernizationofweaponsandtransitionofstrategiesandtactics,theincidenceofblastinjuriesinthebattlefieldkeptincreasing.Spineandspinalcord,owingtotheircentralnervoussystemproperty,onceinjured,wouldatleastaffectthebattleforce,andinmanyseverecaseswouldcauseparalysis.Especiallyforthoseparalyzed,theworkofnursingisverydifficultandveryexpensiveaswell,andthey’repronetodevelopvariouskindsofcomplications.Asaresult,battleinjuriesofspineandspinalcordhavebeenthefocusofrelevantdepartmentsineverycountry.Inthepast,theresearchincentralnervoussystemhotweaponinjuriesespeciallythoseofthespineandspinalcordfocusedmainlyonbulletshotinjuries.However,withtherenewalofsinglesoldierprotectivefacilities,andincreaseofterroristactivities,thenumberofsimplebulletshotinjuriesdecreased,andthenumberofblastinjuriesincreasedmarkedly.Toourknowledge,uptonowtherehasn’tbeenasatisfactoryspineandspinalcordblastinjuryanimalmodel,andthismadetheresearchesonspinalcordblastinjurymechanismsretardedandtherescueworkinarelativelylowlevel.Theaimofthepresentstudywastoestablish第四军医大学硕士学位论7aexperimentalspinalcordblastinjuryanimalmodel,whichtothelargestextentsimulatestheinjuringeffectofshockwaveinthebattlefield.Wealsoobservedthehistopathologicalprogressionofspineandspinalcordinjurytissues,andtheninvestigatedtheeffectofMethylprednisolone(MP)incontrolofsecondaryspinalcordinjuriesafterspinalcordblastinjuries.Wehopethiscanprovidesomeevidencefortheclinicaltreatmentofspinalcordblastinjuries.Thefirstpartoftheresearchwastheestablishmentofacontrollablespinalcordblastinjuryanimalmodel.TheRDXmilitaryexplosivewaschosenastheexplosivematerial。Thepaper-madeshellensuredtherepeatabilitybyrulingoutthebiasofshrapnel.Theanimalwassheltered,leavingonlythethoracicspineatthelevelofinferiorscapulaangulusrightinferiortotheexplosivesource.Theexplosivewaselectricallyignited.Theoptimaldistancefromtheexplosivesourcewaschosenafterpre-measurementofexplosiveparametersandseverityofinjuriesoftheanimalatdifferentdistances.Thedistanceof1,2,4and8cmwereassessed,andfinally4cmwaschosentobethestandardizeddistancetoestablishthespinalcordblastinjurymodel.Theanimalinexperimentswithlessthan4cmdistancefromtheexplosivesourcediedimmediately.Autopsyshowedlargepiecesofsofttissueavulsionatthewound,deepspinalplatefracture,pulmonarycongestionandthoracicmajorbloodvesselrupture.Thedistanceof4cmformtheexplosivesourcedidn’tcauseanyanimaldeath.Thepathologyshowedacutespinalcordinjurycharacteristics6hoursafterexplosion,withobviousspinalcordedemaandswollenneurons;irreversibledegradationsofneuronsafter24hours,withNisslbodydisappearing,nucleuscondensingandredstaining,looseningorevenbreakdownofspinalcord第四军医大学硕士学位论8shelllaminarstructure;andobviousnecrosisareasinthespinalcordafter3days.Functionalexaminationsshoweddisappearanceofbothsensationandmovementabilityinthehindlimbs.ThesecondpartoftheresearchinvestigatedtheeffectsofMPtherapyonspinalcordtissueandserumlevelsofCa2+、MDAandSODafteracutespinalco