中华心血管病杂志
中華心血管病雜誌
중화심혈관병잡지
Chinese Journal of Cardiology
2013年
11期
950-954
,共5页
心肌梗死%再生%细胞增殖
心肌梗死%再生%細胞增殖
심기경사%재생%세포증식
Myocardial infarction%Rgeneration%Cell proliferation
目的 评估急性心肌梗死后,不同缺血时段心脏不同部位心肌细胞增殖变化,探讨增殖发生时间和部位、分布特点及增殖细胞是否与心脏干细胞有关联及其在修复损伤心肌中的可能作用.方法 成年SD大鼠64只按随机数字表法分为2组,实验组(n=44)开胸结扎冠状动脉前降支制作急性心肌梗死模型,对照组(n=20)开胸置缝线而不结扎.于术后第3、5、7、14和60 d处死大鼠(第7和14天两组各9只,其余各组均为5只),采集左心室梗死边缘区及右心室非梗死区心肌组织.处死大鼠前12和24 h分别腹腔注射50 mg/kg5-溴-2-脱氧尿苷(Brdu).HE染色观察心肌组织形态学和病理学变化,用免疫组化方法检测Brdu阳性心肌细胞数量;磷钨酸苏木素(PTAH)染色检测新生细胞的横纹结构;α-横纹肌肌动蛋白抗体检测判别增殖的细胞是否为心肌细胞;免疫荧光法测定Brdu和c-kit阳性的心肌细胞.结果 实验组大鼠急性心肌梗死后第5天梗死边缘区和非梗死区Brdu阳性心肌细胞明显多于对照组(P＜0.01);第7天梗死边缘区Brdu阳性心肌细胞达高峰,为对照组的5.7倍[(1.26±0.15)％比(0.22±0.06)％,P＜O.01],非梗死区为对照组的4.2倍[(0.75±0.12)％比(0.18±0.07)％,P＜0.01];第60天两组差异无统计学意义.实验组第7天梗死边缘区的Brdu阳性细胞数量为右心室非梗死区的1.7倍[(1.26±0.15)％比(0.75±0.12)％,P＜0.01],第14天为1.4倍[(0.77±0.09)％比(0.54±0.11)％,P＜0.01].PTAH染色显示部分增殖的新生细胞有心肌横纹结构.免疫荧光检测显示部分Brdu阳性细胞心肌肌动蛋白标记阳性;梗死边缘区部分Brdu阳性细胞c-kit标记亦阳性,这些心肌细胞核较小且圆.结论 急性心肌梗死后,成年大鼠新生心肌细胞明显增多,梗死边缘区及右心室非梗死区均显著高于对照组,心肌细胞增殖和(或)再生现象呈时间依赖性.部分新生的心肌细胞具有心脏干细胞特性.本研究表明急性心肌缺血损伤后心肌细胞似有激活增殖和(或)再生的现象.
目的 評估急性心肌梗死後,不同缺血時段心髒不同部位心肌細胞增殖變化,探討增殖髮生時間和部位、分佈特點及增殖細胞是否與心髒榦細胞有關聯及其在脩複損傷心肌中的可能作用.方法 成年SD大鼠64隻按隨機數字錶法分為2組,實驗組(n=44)開胸結扎冠狀動脈前降支製作急性心肌梗死模型,對照組(n=20)開胸置縫線而不結扎.于術後第3、5、7、14和60 d處死大鼠(第7和14天兩組各9隻,其餘各組均為5隻),採集左心室梗死邊緣區及右心室非梗死區心肌組織.處死大鼠前12和24 h分彆腹腔註射50 mg/kg5-溴-2-脫氧尿苷(Brdu).HE染色觀察心肌組織形態學和病理學變化,用免疫組化方法檢測Brdu暘性心肌細胞數量;燐鎢痠囌木素(PTAH)染色檢測新生細胞的橫紋結構;α-橫紋肌肌動蛋白抗體檢測判彆增殖的細胞是否為心肌細胞;免疫熒光法測定Brdu和c-kit暘性的心肌細胞.結果 實驗組大鼠急性心肌梗死後第5天梗死邊緣區和非梗死區Brdu暘性心肌細胞明顯多于對照組(P＜0.01);第7天梗死邊緣區Brdu暘性心肌細胞達高峰,為對照組的5.7倍[(1.26±0.15)％比(0.22±0.06)％,P＜O.01],非梗死區為對照組的4.2倍[(0.75±0.12)％比(0.18±0.07)％,P＜0.01];第60天兩組差異無統計學意義.實驗組第7天梗死邊緣區的Brdu暘性細胞數量為右心室非梗死區的1.7倍[(1.26±0.15)％比(0.75±0.12)％,P＜0.01],第14天為1.4倍[(0.77±0.09)％比(0.54±0.11)％,P＜0.01].PTAH染色顯示部分增殖的新生細胞有心肌橫紋結構.免疫熒光檢測顯示部分Brdu暘性細胞心肌肌動蛋白標記暘性;梗死邊緣區部分Brdu暘性細胞c-kit標記亦暘性,這些心肌細胞覈較小且圓.結論 急性心肌梗死後,成年大鼠新生心肌細胞明顯增多,梗死邊緣區及右心室非梗死區均顯著高于對照組,心肌細胞增殖和(或)再生現象呈時間依賴性.部分新生的心肌細胞具有心髒榦細胞特性.本研究錶明急性心肌缺血損傷後心肌細胞似有激活增殖和(或)再生的現象.
목적 평고급성심기경사후,불동결혈시단심장불동부위심기세포증식변화,탐토증식발생시간화부위、분포특점급증식세포시부여심장간세포유관련급기재수복손상심기중적가능작용.방법 성년SD대서64지안수궤수자표법분위2조,실험조(n=44)개흉결찰관상동맥전강지제작급성심기경사모형,대조조(n=20)개흉치봉선이불결찰.우술후제3、5、7、14화60 d처사대서(제7화14천량조각9지,기여각조균위5지),채집좌심실경사변연구급우심실비경사구심기조직.처사대서전12화24 h분별복강주사50 mg/kg5-추-2-탈양뇨감(Brdu).HE염색관찰심기조직형태학화병이학변화,용면역조화방법검측Brdu양성심기세포수량;린오산소목소(PTAH)염색검측신생세포적횡문결구;α-횡문기기동단백항체검측판별증식적세포시부위심기세포;면역형광법측정Brdu화c-kit양성적심기세포.결과 실험조대서급성심기경사후제5천경사변연구화비경사구Brdu양성심기세포명현다우대조조(P＜0.01);제7천경사변연구Brdu양성심기세포체고봉,위대조조적5.7배[(1.26±0.15)％비(0.22±0.06)％,P＜O.01],비경사구위대조조적4.2배[(0.75±0.12)％비(0.18±0.07)％,P＜0.01];제60천량조차이무통계학의의.실험조제7천경사변연구적Brdu양성세포수량위우심실비경사구적1.7배[(1.26±0.15)％비(0.75±0.12)％,P＜0.01],제14천위1.4배[(0.77±0.09)％비(0.54±0.11)％,P＜0.01].PTAH염색현시부분증식적신생세포유심기횡문결구.면역형광검측현시부분Brdu양성세포심기기동단백표기양성;경사변연구부분Brdu양성세포c-kit표기역양성,저사심기세포핵교소차원.결론 급성심기경사후,성년대서신생심기세포명현증다,경사변연구급우심실비경사구균현저고우대조조,심기세포증식화(혹)재생현상정시간의뢰성.부분신생적심기세포구유심장간세포특성.본연구표명급성심기결혈손상후심기세포사유격활증식화(혹)재생적현상.
Objective To investigate the myocardial proliferation/regeneration capacities at different time points and at different parts of the heart post acute myocardial infarction (AMI) in rats.Methods A total of 64 adult Sprague-Dawley (SD) rats were randomly divided into AMI group (left anterior descending coronary ligation,n =44) and sham-operated group (n =20).Rats were sacrificed on day 3,5,7,14 and 60 respectively post operation (n =5-9 at each time point) and ventricular tissues were harvested.5-Bromo-2-deoxyUridine (Brdu,50 mg/kg) was injected intraperitoneally at 12 and 24 hours before sacrifice.Morphological and pathological changes of the myocardium were observed after HE staining.Brdu-positive and c-kit and Brdu double-positive cardiomyocytes were analyzed post immunohistochemistry and immunofluorescence staining.Striated structure of new cells was detected by PTAH staining.Alpha-sarcomeric actin antibody was used to identify new cardiomyocytes.Result Brdupositive cardiomyocytes at border zone and non-ischemic zone were significantly increased at 5 days post AMI and peaked at 7th day post operation (Border zone,AMI:1.26％ ±0.15％ vs.Sham:0.22％ ±0.06％,P ＜0.01; right ventricle,AMI:0.75％ ± 0.12％ vs.Sham:0.18％ ±0.07％,P＜0.01).There was no significant difference between the two groups on the 60th post-operation day.Brdu-positive cells were 1.7-fold higher in infarct border zone than in the right ventricular area of AMI rats on the 7th post operation day (1.26％ ±0.15％,vs.0.75％ ±0.12％,P ＜0.01) and was 1.4-fold higher on the 14th post operation day (0.77％ ± 0.09％,vs.0.54％ ± 0.11％,P ＜ 0.01).PTAH staining evidenced myocardial striated structure inside the new cells.Immunofluorescent assay showed that parts of Brdu positive cells were myocardial actin positive,and the c-kit and Brdu double-positive myocardial cells were also observed.Most nuclei of tehse new cardiomyocytes were small and round-shaped.Conclusions Myocardial proliferation/regeneration increased significantly after AMI in rats,especially around the infarct border zone.The myocardial proliferation/ regeneration was time-dependent.Parts of the new cardiomyocytes had some characteristics of cardiac stem cells.This study suggests that myocardial proliferation/regeneration may be activated after acute myocardial injury.
