内皮素-1及其受体在心肌梗死心脏组织中分布的研究

目的　内皮素 -1(ET -1)在心肌梗死的发生发展和病理性重构中发挥重要的病理生理作用。但是 ,ET -1及其受体A (ETA)在正常及心梗后心脏各房室中的分布情况目前还不完全清楚。本研究旨在探索这一问题。方法　以成年西双版纳微型猪为实验对象 ,实验组 (n =6)开胸并结扎冠状动脉左前降支建立心肌梗死模型 ,对照组 (n =5)模拟开胸手术过程 ,但不结扎冠状动脉。 4周后取出心脏 ,分部位用免疫组化及图像分析检测心肌组织ET -1和ETA 水平。结果　 1 对照组ET -1和ETA以右房分布最多 ,左室分布最少 (P <0 0 0 0 1) ;2 心肌梗死后受累左室ET -1明显增多 ,ETA 显著上调 (P <0 0 0 0 1) ;3 在梗死中心区的血管内皮细胞、成纤维细胞、浆细胞和淋巴细胞检测出ET -1。结论　ET -1在心肌梗死后的心脏重构、血管增生、炎症反应、组织修复及疤痕形过程中可能发挥重要的作用

The localization of endothelin-1 and its receptor in the porcine heart after myocardial infarction

ObjectiveEndothelin-1 is associated with myocardial infarcti on (MI),but its localization in normal heart or heart after MI is unclear.The aim of the present study was to elucidate this problem.MethodsElev en adult miniswines were divided into two groups.Myocardial infarction was induced by ligating the left anterior descending coronary artery(n=6).Sham-operated animals were served as contr ols( n=5).Hearts were examined by immunohistochemistry (including ET-1 and ET A )and image analysts after 4 weeks.Results(1)In controls,the level of ET-1-like-immun oreactivity(ET-1-ir)and ET A-like immunoreactivity(ET A-ir)in right atrium sho wed a considerable high compared with other regions(P<0 0001,respectivel y),a nd the lowest was in left ventricle.(2)In MI-swines,the level of ET-1-and ET A- ir in the infarcted area were significantly increased (P<0 0001).(3)ET-1-i r wa s seen over remaining cardiomyocytes,endothelial cells,fibroblasts and inflammat ory cells in the infarcted area.ConclusionsET-1 and ETA A mos tly localize in the right atrium in normal heart,and they increase in the infarcted region regio n after MI.The results suggest that ET-1 plays an important pathophysiological r ole in cardiac remodeling,neovascularization,inflammatory response,tiss ue repair and cicatrisation after MI.