摘要
目的 评价七氟醚预处理对大鼠心肌缺血再灌注时紧密连接蛋白1（ZO-1）的影响.方法 成年雄性Wistar大鼠,体重250 ～ 300 g,建立Langendorff离体心脏灌注模型.取离体心脏模型18个,采用随机数字表法,将其分成3组（n=6）：对照组（C组）、缺血再灌注组（I/R组）和七氟醚预处理组（S组）.平衡灌注10 min后,C组继续灌注K-H液110 min;I/R组继续灌注K-H液20 min,全心缺血30 min,再灌注60min;S组灌注经3％七氟醚预充饱和的K-H液15 min,洗脱5 min,全心缺血30 min,再灌注60 min.分别于平衡灌注末、缺血前即刻、再灌注15和60 min时记录心率（HR）、左室舒张末压（LVEDP）、左室发展压（LVDP）、左心室内压最大上升速率（＋dp/dtmax）和左心室内压最大下降速率（-dp/dtmax）.再灌注期间记录心律失常的发生情况,并进行评分.于再灌注60 min时取心尖部组织,采用Western blot法检测ZO-1表达;免疫荧光法测定ZO-1和缝隙连接蛋白43（Cx43）的分布情况.结果 与C组比较,I/R组再灌注15和60 min时HR、LVDP、＋dp/dtmax和-dp/dtmax降低,LVEDP和心律失常评分升高,心肌组织ZO-1表达下调,ZO-1再分布率升高（P＜0.05）.与I/R组比较,S组再灌注15和60 min时HR、LVDP、＋dp/dtmax和-dp/dtmax升高,LVEDP和心律失常评分降低,心肌组织ZO-1表达上调（P＜0.05）.C组ZO-1与Cx43共定位于闰盘处;I/R组位于闰盘处的ZO-1再分布至心肌细胞侧膜,并在侧膜与Cx43发生共定位;S组ZO-1再分布率降低（P＜0.05）.结论 七氟醚预处理降低大鼠再灌注性心律失常发生的机制与抑制ZO-1的表达下调和再分布,从而抑制Cx43的再分布有关.
Objective To evaluate the effects of sevoflurane preconditioning on zonula occludens-1 （ZO-1） during myocardial ischemia-reperfusion （I/R） in rats in vitro.Methods Adult male Wistar rats,weighing 250-300 g,were anesthetized with intraperitoneal pentobarbital 30 mg/kg and heparinized.Their hearts were excised and perfused in a Langendorff apparatus with K-H solution saturated with 95% O2-5% CO2 at 37 ℃.Eighteen isolated rat hearts were randomly assigned into 3 groups （n =6 each） using a random number table：control group （group C）,group I/R and sevoflurane preconditioning group （group S）.At 10 min of equilibration,the hearts were perfused with K-H solution for 110 min in group C,the hearts were perfused with K-H solution for 20 min,and then subjected to 30 min of ischemia followed by 60 min of reperfusion in group I/R,and the hearts were perfused with K-H solution saturated with 3% sevoflurane for 15 min followed by 5 min washout,and then subjected to 30 min of ischemia followed by 60 min of reperfusion in group S.At the end of equilibration,immediately before ischemia,and at 15 and 60 min of reperfusion （T1,2）,HR,left ventricular end-diastolic pressure （LVEDP）,left ventricular developed pressure （LVDP）,＋ dp/dtmax and-dp/dtmax were recorded.The development of arrhythmias was recorded during reperfusion and scored.At 60 min of reperfusion,myocardial specimens were obtained from the apex of heart for determination of the expression of ZO-1 in myocardial tissues （by Western blot） and for observation of distribution of ZO-1 and connexin43 （Cx43） （by immunofluorescence）.Results Compared with group C,HR,LVDP,＋ dp/dtmax and-dp/dtmax were significantly decreased and LVEDP was increased at 15 and 60 min of reperfusion,scores of arrhythmia was increased,and ZO-1 expression was down-regulated in I/R group.Compared with group I/R,HR,LVDP,＋ dp/dtmax and-dp/dtmax were significantly increased and LVEDP was decreased at 15 and 60 min of reperfusion,arrhythmia was decreased,and ZO-1 expression was up-regulated in group S.ZO-1 and Cx43 were co-localized at the intercalated disk.ZO-1 was redistributed in the lateralization of the membrane and co-localized with Cx43 in group I/R.The incidence of ZO-1 lateralization was significantly decreased in group S.Conclusion The mechanism by which sevoflurane preconditioning decreases reperfusion arrhythmia is related to inhibition of down-regulation of expression and redistribution of ZO-1 and inhibition of redistribution of Cx43 in rats.
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2014年第10期1263-1266,共4页
Chinese Journal of Anesthesiology
关键词
麻醉药
吸入
缺血预处理
心肌再灌注损伤
紧密连接部
Anesthetics, inhalation
Ischemic preconditioning
Myocardial reperfusion injury
Tight junctions
