CAJ | 학술논문

目的探讨大鼠冠状动脉微栓塞致心肌细胞凋亡与天冬氨酸特异性半胱氨酸蛋白酶(Caspase)-12活化的动态变化规律及其关系.方法选取成年雄性SD大鼠,建立冠状动脉微栓塞模型,随机分为微栓塞组、假手术组.每组存活大鼠再随机分为3 h、6 h、12 h、24 h、4周组,各时间点各组大鼠均为10只.另10只大鼠作正常对照组.缺口末端标记法检测心肌细胞凋亡,免疫印迹法检测Caspase-3及Caspase-12酶原及其活化产物,荧光酶标法检测Caspase-12活性.结果 (1)与正常对照组、假手术组相应时间点比较,微栓塞组各时间点心肌细胞凋亡率显著升高(均P<0.05),心肌细胞凋亡主要分布在微梗死区及其边缘区.微栓塞组心肌细胞凋亡率在3 h、6 h、12 h、24 h、4周分别为(1.76±0.68)%、(3.17±1.26)%、(1.34±0.12)%、(1.07±0.65)%、(0.30±0.13)%,冠状动脉微栓塞后6 h心肌细胞凋亡达高峰(均P<0.05).(2)与正常对照组、假手术组相应时间点比较,微栓塞组各时间点Caspase-3、Caspase-12的相对活化水平升高(均P<0.05),其随时间变化规律与心肌细胞凋亡的时间变化规律一致.结论大鼠冠状动脉微栓塞致心肌细胞凋亡增加,在微栓塞后6 h达高峰,具有动态变化规律.Caspase-12可能参与了冠状动脉微栓塞致心肌细胞凋亡.
목적 탐토대서관상동맥미전새치심기세포조망여천동안산특이성반광안산단백매(Caspase)-12활화적동태변화규률급기관계.방법 선취성년웅성SD대서,건립관상동맥미전새모형,수궤분위미전새조、가수술조.매조존활대서재수궤분위3 h、6 h、12 h、24 h、4주조,각시간점각조대서균위10지.령10지대서작정상대조조.결구말단표기법검측심기세포조망,면역인적법검측Caspase-3급Caspase-12매원급기활화산물,형광매표법검측Caspase-12활성.결과 (1)여정상대조조、가수술조상응시간점비교,미전새조각시간점심기세포조망솔현저승고(균P<0.05),심기세포조망주요분포재미경사구급기변연구.미전새조심기세포조망솔재3 h、6 h、12 h、24 h、4주분별위(1.76±0.68)%、(3.17±1.26)%、(1.34±0.12)%、(1.07±0.65)%、(0.30±0.13)%,관상동맥미전새후6 h심기세포조망체고봉(균P<0.05).(2)여정상대조조、가수술조상응시간점비교,미전새조각시간점Caspase-3、Caspase-12적상대활화수평승고(균P<0.05),기수시간변화규률여심기세포조망적시간변화규률일치.결론 대서관상동맥미전새치심기세포조망증가,재미전새후6 h체고봉,구유동태변화규률.Caspase-12가능삼여료관상동맥미전새치심기세포조망.
Objective To investigate the dynamic changes of cardiomyocyte apoptosis and Caspase-12 activation after coronary microembolization (CME) in rats. Methods The CME models were produced by injection of 42 μm microspheres (3000/0.1 ml) into the left ventricle during clampinduced ascending aorta occlusion for 10 seconds in adult male Sprague-Dawley rats (CME group).The sham-operation group was injected with saline instead (S group). The survivors were randomly divided into five groups: 3 h, 6 h, 12 h, 24 h and 4 weeks (n=10, each), respectively. In addition,10 rats were designed as normal control group. Cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. The expressions of Caspase-3, 12 and procaspase-3 and 12 were detected with Western-blot analysis. The activity of Caspase-12 was determined with fluorometric assay kit. Results (1)Compared with the shamoperation group and normal control group, the apoptosis rates of cardiomyocytes in CME group were significantly increased at each time point respectively (all P＜0.05). Apoptotic cardiomyocytes were found mainly in the border zones and infarct foci. The apoptosis rates of cardiomyocytes at 3 h, 6 h,12 h, 24 h and 4 weeks after CME were (1.76±0.68)%, (3.17±1.26)%, (1.34±0.12)%,(1.07±0.65)% and (0.30±0.13)%, respectively. The apoptosis rates of cardiomyocytes increased at 3 h after CME, peaked at 6 h after CME (all P＜0.05), and then gradually decreased with lowest value at 4 weeks (all P＜0.01). (2)Compared with sham-operation group and normal control group,the relative activation level of Caspase-3 and 12 in CME group increased remarkably (all P＜0.05).The time courses of Caspase-3 and 12 expressions corresponded well to those of cardiomyocyte apoptosis after CME. Conclusions The amount of cardiomyocytes apoptosis is significantly increased after CME. Caspase-12 may be involved in the apoptosis of cardiomyocyte after CME.