【作者】 方文倩；

【导师】 吕国义；

【作者基本信息】 天津医科大学 ， 麻醉学， 2010， 硕士

【摘要】 观察利多卡因(Lidocaine, Lido)及联合缺血后处理(Postconditioning, IPO)对离体大鼠全心缺血—再灌注损伤(Myocardical ischemia reperfusion injury, MIRI)的保护作用,探讨可能的作用机制及作用特点。40只健康成龄雌性wistar大鼠,体重220g-250g,随机分为5组,每组8只。3%戊巴比妥钠50 mg/kg腹腔注射麻醉,肝素(500 IU/kg)腹腔注射抗凝。麻醉满意后,开胸快速取出心脏,连接到改良Langendorff灌注装置上,维持离体鼠心实验全程处于37℃恒温下,K-H液(Kerbs-Henseleit Bicarbonate Buffer, KHB)平衡灌注10min后,对照(A)组：灌注K-H液20 min,全心缺血30min,再灌注60 min；缺血后处理(B)组：K-H液灌注20 min,全心缺血30 min,再灌注开始行灌注10 s/缺血10s的6次循环,再灌注58 min；利多卡因(C)组：灌注含2.5 mg/L利多卡因的K-H液20 min,全心缺血30 min,再灌注相应灌流液60 min；利多卡因+格列苯脲(D)组：灌注含2.5 mg/L利多卡因和10μmol/L格列苯脲的K-H液20 min,全心缺血30 min,再灌注相应灌流液60 min。利多卡因+缺血后处理(E)组：灌注含2.5 mg/L利多卡因的K-H液20 min,全心缺血30 min,再灌注开始行灌注10 s/缺血10s的6次循环,再灌注相应灌流液58 min。记录各组平衡灌注末及再灌注15min、30 min、45 min、60 min时的心功能参数：心率(Heart rate,HR)、左心室形成压(Left ventricular developed pressure, LVDP)、左室内压上升最大速率(differential pressure timemaxium,+dp/dtmax)、左室内压下降最大速率(differential pressure timemaxium,-dp/dtmax)。留取各组平衡灌注末及再灌注末冠脉流出液,测定肌酸激酶(Creatine Kinase,CK),乳酸脱氢酶(Lactate Dehydrogenase,LDH)活性。实验结束后,留取各组大鼠心尖周围组织约200 mg于液氮中保存,备测定丙二醛(Malondialdehyde, MDA)、超氧化物歧化酶(Superoxide Dismutase,SOD)、三磷酸腺苷酶(Adenosine riphosphatase,ATP ase)及钙离子(Calciumion,Ca2+)含量。(1)心功能参数变化各组缺血前HR、LVDP、+dp/dtmax、-dp/dtmax无显著性差异(P>0.05)；缺血再灌注后各组HR、LVDP、+dp/dtmax、-dp/dtmax均有下降趋势(P<0.05)；与A组比较,B、C组心功能较好(P<0.05)；B,C两组间比较差异无统计学意义(P>0.05)；与C组比较,D组心功能较差(P<0.05)；与A组比较,E组心功能明显升高(P<0.01),且高于B组(P<0.05)；A、D两组间比较差异无统计学意义(P>0.05)。(2)对心肌漏出酶的影响缺血前各组大鼠CK、LDH活性差异无统计学意义(P>0.05)；再灌注末,与A组比较,B、C组CK、LDH活性较低(P<0.05)；B,C两组间比较差异无统计学意义(P>0.05)；与C组比较,D组CK、LDH活性较高(P<0.05)；与A组比较,E组CK、LDH活性明显降低(P<0.01),且低于B组(P<0.05)；A、D两组间比较差异无统计学意义(P>0.05)。(3)对心肌组织酶和离子含量的影响再灌注末,与A组比较,B、C组心肌组织SOD、ATPase含量较高(P<0.05),MDA,Ca2+含量较低(P<0.05)；B,C两组间比较差异无统计学意义(P>0.05)；与C组比较,D组心肌组织SOD、ATPase含量降低(P<0.05),MDA,Ca2+含量升高(P<0.05)；与A组比较,E组心肌组织SOD、ATPase含量明显升高(P<0.01),且高于B组(P<0.05),MDA,Ca2+含量明显降低(P<0.01),且低于B组(P<0.05)；A、D两组间比较差异无统计学意义(P>0.05)。含2.5 mg/L利多卡因的K-H液能改善缺血—再灌注心脏功能,减轻心肌细胞损伤,对心肌缺血—再灌注损伤具有一定的保护作用,其保护效果与缺血后处理相似,机制可能与利多卡因介导促进心脏ATP敏感性钾通道(KATP通道)开放有关；与缺血后处理联合使用后心肌保护效果更佳。更多还原

【Abstract】 To investiagate the effects of Lidocaine on myocardial ischemia reperfusion injury in global isolated rat heart, approach both the possible mechanism and its feature of the action.40 healthy majoritied female wastar rats, weighing about 220g-250g, were randomly divided into 5 groups (8 in each), including control group (A), ischiemic postconditioning group (B), lidocaine group (C), lidocaine+glibenclamide group (D), and lidocaine+postconditioning group(E).The rats were anesthetized with 3% pentobarbital sodium 50 mg/kg inter-peritoneally and heparinized (500 IU/kg). After thoracotomy the heart was rapidly removed and mounted on modified Langendorff apparatus,and kept the hearts in 37℃. In A group, each heart was perfused with Kerbs-Henseleit Bicarbonate buffer (KHB) for 20 min, then subjected to 30 min global ischemia followed by 60 min reperfusion.; group B with KHB for 20 min, then 30 min global ischemia followed by 6 cycles of 10s ischemia and 10s reperfusion,then 58 min reperfusion; group C with 2.5 mg/L Lidocaine in KHB for 20 min, then 30 min global ischemia followed by 60 min reperfusion; group D with 2.5mg/L lidocaine and 10μmol/L glibenclamide in KHB for 20 min, then 30 min global ischemia followed by 60 min reperfusion; group E with 2.5 mg/L lidocaine in KHB for 20 min, then 30 min global ischemia followed by 6 cycles of 10s ischemia and 10s reperfusion,then 58 min reperfusion.Heamodynamic parameters:HR、left LVDP、+dp/dtmax and-dp/dtmax were recorded at baseline, and at the end of 15 min、30 min、45 min and 60 min of reperfusion. CK and LDH were measured at baseline, and at the end of 60 min of reperfusion. Tissue arround apexes, weighing about 200 mg was cutted after the experiment. Concentrations of MDA、SOD、ATPase and Ca2+ in myocardium were measuered.(1) Influence on hemodynamics There were no statistical significances in HR, LVDP,+dp/dtmax,-dp/dtmax before ischemia among five groups (P>0.05). After ischemia-reperfusion, HR、LVDP、+dp/dtmax and -dp/dtmax tends to decrease in each group.both B and C were improved (P<0.05) compared with A.there was no statistical significance between B and C (P>0.05); D was much lower compared with C(P<0.05). E was much higher compared with A (P<0.01) and B (P<0.05). There was no statistical significance between A and D (P>0.05). (2) Influence on myocardial enzymes leak There were no statistical significances in CK and LDH among five groups before ischemia (P>0.05). After reperfusion, both CK and LDH in B and C were much lower than that of A (P<0.05), there was no statistical significance between B and C(P>0.05)), both CK and LDH in D was much lower compared with C (P<0.05); both were much higher in E compared with A (P<0.01) and B (P<0.05); there was no statistical significance between A and D (P>0.05). (3) Influence on myocardial enzyme and calcium irons After reperfusion, SOD and ATPase were much higher, contents of Ca2+ and MDA were much lower in B and C than that of A (P<0.05), there was no statistical significance between B and C(P>0.05); SOD and ATPase were higher, contents of Ca2+ and MDA were much lower in D (P<0.05) compared with C; SOD and ATPase were much higher, contents of Ca2+ and MDA were much lower in E compared with A (P<0.01) and B (P<0.05); there was no statistical significance between A and D (P>0.05).2.5 mg/L lidocaine in KHB can protect myocardium from ischemia reperfusion injury in global isolated rat heart,and the effects is similar with ischiemic postconditioning. The possible mechnism is promoting opening the ATP-sensitive potassium channel (KATP)-The effects of myocardial protection is much better if combining with ischemic postconditioning.更多还原