CAJ | 학술논문

目的：评价DJ?1与糖尿病因素影响大鼠缺血后处理心肌保护作用的关系。方法健康雄性SD大鼠，3月龄，体重220～250 g。采用腹腔注射1％链脲佐菌素60 mg∕kg的方法制备大鼠糖尿病模型，取糖尿病模型制备成功的大鼠48只，采用随机数字表法，将其分为3组（ n＝16）：假手术组（ DM?S组）、心肌缺血再灌注组（ DM?IR组）和缺血后处理组（ DM?IPO组）；另取大鼠48只，腹腔注射等容量柠檬酸盐缓冲液作为对照，采用随机数字表法，将其分为3组（ n＝16）：假手术组（ S组）、心肌缺血再灌注组（ IR组）和缺血后处理组（ IPO组）。给予链脲佐菌素后12周，采用结扎左冠状动脉前降支30 min再灌注120 min的方法制备大鼠心肌缺血再灌注损伤模型；缺血后处理的实施：于缺血30 min时，给予3个循环的再灌注10 s，缺血10 s。于再灌注120 min时，采用TTC法确定心肌梗死体积，取心肌组织，采用Western blot法测定DJ?1、10号染色体上缺失性磷酸酶与张力蛋白同源物基因（ PTEN）蛋白和磷酸化丝氨酸?苏氨酸蛋白激酶（ p?Akt）的表达。结果非糖尿病大鼠和糖尿病大鼠心肌缺血再灌注时心肌梗死体积增大，非糖尿病大鼠心肌组织DJ?1、PTEN蛋白和p?Akt的表达上调，糖尿病大鼠心肌组织PTEN蛋白和p?Akt的表达上调，而心肌组织DJ?1表达无变化；缺血后处理可缩小非糖尿病大鼠心肌缺血再灌注时心肌梗死体积，进一步上调心肌组织DJ?1和p?Akt的表达，下调心肌组织PTEN蛋白表达，而对糖尿病大鼠无此作用；与非糖尿病大鼠比较，缺血后处理后糖尿病大鼠心肌缺血再灌注时心肌组织DJ?1和p?Akt表达下调，心肌组织PTEN蛋白表达上调。结论糖尿病因素取消大鼠缺血后处理心肌保护作用的机制与其下调DJ?1表达有关。
목적：평개DJ?1여당뇨병인소영향대서결혈후처리심기보호작용적관계。방법건강웅성SD대서，3월령，체중220～250 g。채용복강주사1％련뇨좌균소60 mg∕kg적방법제비대서당뇨병모형，취당뇨병모형제비성공적대서48지，채용수궤수자표법，장기분위3조（ n＝16）：가수술조（ DM?S조）、심기결혈재관주조（ DM?IR조）화결혈후처리조（ DM?IPO조）；령취대서48지，복강주사등용량저몽산염완충액작위대조，채용수궤수자표법，장기분위3조（ n＝16）：가수술조（ S조）、심기결혈재관주조（ IR조）화결혈후처리조（ IPO조）。급여련뇨좌균소후12주，채용결찰좌관상동맥전강지30 min재관주120 min적방법제비대서심기결혈재관주손상모형；결혈후처리적실시：우결혈30 min시，급여3개순배적재관주10 s，결혈10 s。우재관주120 min시，채용TTC법학정심기경사체적，취심기조직，채용Western blot법측정DJ?1、10호염색체상결실성린산매여장력단백동원물기인（ PTEN）단백화린산화사안산?소안산단백격매（ p?Akt）적표체。결과비당뇨병대서화당뇨병대서심기결혈재관주시심기경사체적증대，비당뇨병대서심기조직DJ?1、PTEN단백화p?Akt적표체상조，당뇨병대서심기조직PTEN단백화p?Akt적표체상조，이심기조직DJ?1표체무변화；결혈후처리가축소비당뇨병대서심기결혈재관주시심기경사체적，진일보상조심기조직DJ?1화p?Akt적표체，하조심기조직PTEN단백표체，이대당뇨병대서무차작용；여비당뇨병대서비교，결혈후처리후당뇨병대서심기결혈재관주시심기조직DJ?1화p?Akt표체하조，심기조직PTEN단백표체상조。결론당뇨병인소취소대서결혈후처리심기보호작용적궤제여기하조DJ?1표체유관。
Objective To evaluate the relationship between DJ?1 and diabetes mellitus ( DM )?caused influence on cardioprotection induced by ischemic postconditioning in rats. Methods Adult male Sprague?Dawley rats, aged 3 months, weighing 220-250 g, were used in the study. DM was induced by intraperitoneal injection of 1% streptozotocin 60 mg∕kg and confirmed by blood glucose≥16.7 mmol∕L. Forty?eight rats with DM were randomly divided into 3 groups ( n=16 each) using a random number table:sham operation group ( group DM?S ) , myocardial ischemia?reperfusion ( I∕R ) group ( DM?IR ) and ischemic postconditioning group (DM?IPO group). Another 48 normal rats received the equal volume of citrate buffer solution instead and served as control. Those rats were randomly divided into 3 groups ( n=16 each) using a random number table: sham operation group ( S group) , myocardial I∕R group ( IR group) and ischemic postconditioning group (IPO group). At 12 weeks after streptozotocin injection, myocardial I∕R was produced by 30 min occlusion of the left anterior descending branch of the coronary artery followed by 120 min reperfusion. Ischemic postconditioning was induced by 3 cycles of 10 s reperfusion followed by 10 s limb ischemia at the end of 30 min limb ischemia. At 120 min of reperfusion, the animals were sacrificed, and hearts were removed for determination of myocardial infarction size ( using TTC ) , and expression of DJ?1, phosphatase and tensin homologue ( PTEN) protein, and phosphorylated Akt ( p?Akt) in myocardial tissues ( by Western blot) . Results The infarction size was significantly increased in diabetic and nondiabetic rats during myocardial I∕R. The expression of DJ?1, PTEN protein and p?Akt was significantly higher during myocardial I∕R in nondiabetic rats, and the expression of PTEN protein and p?Akt was up?regulated, and no significant change was found in DJ?1 expression during myocardial I∕R in diabetic rats. Ischemic postconditioning reduced infarction size during myocardial I∕R and up?regulated the expression of DJ?1 and p?Akt, and down?regulated the expression of PTEN protein in nondiabetic rats, but not in diabetic rats. Compared with nondiabetic rats, the expression of DJ?1 and p?Akt was down?regulated, and the expression of PTEN protein was up?regulated after ischemic postconditioning in diabetic rats. Conclusion The mechanism by which DM abolishes cardioprotection induced by ischemic postconditioning is associated with down?regulation of DJ?1 expression in rats.