成年大鼠心肌Ⅰ、Ⅲ型胶原蛋白的共表达

Co-expression of collagen Ⅰ and Ⅲ in the adult rat myocardium

目的探讨成年大鼠心肌中Ⅰ、Ⅲ型胶原蛋白的组织学构筑及比例关系。方法采用免疫组织化学、免疫荧光双标记和Western blotting等方法,观察10只成年大鼠心肌Ⅰ、Ⅲ型胶原的构筑特点;利用图像分析系统对Ⅰ、Ⅲ型胶原进行定量分析。结果Ⅰ型胶原主要表达在心肌细胞群周围和血管外膜,多形成粗纤维,Ⅲ型胶原主要表达于每个心肌细胞周围和血管外膜,主要构成细纤维。免疫荧光双标记显示,粗、细两种胶原纤维均含有Ⅰ、Ⅲ型胶原蛋白。心肌Ⅲ型胶原总含量略高于Ⅰ型胶原。结论由粗细胶原纤维构成的心肌胶原网络是由Ⅰ型和Ⅲ型胶原蛋白共同构成,任何一种蛋白改变都可能影响心肌间质的功能。

Objective To define the relation ship between the histological architecture and the proportion of collagen Ⅰ and Ⅲ in the rat myoeardium. Methods Immunohistochemistry, immunofluorescence double labeling and Western blotting were used for studying construction characteristics of collagen Ⅰ and Ⅲ in 10 adult rat hearts. Collagen Ⅰ and Ⅲ were quantified by image analysis system. Results Collagen Ⅰ formed mainly thick fibers which were mainly distributed around bundles of myocardial cell and tunica adventitia of cardiac vessels, whereas collagen Ⅲ formed thin collagen fibers which were around bundles myocardial cells and tunica adventitia of the vessels. However, both thick and thin collagen fibers contained various proportions of collagen Ⅰ and Ⅲ. Conclusion The Collagen network in the rat heart was composed of thick and thin collagen fibers. Both types of fibers were constructed by type Ⅰ and Ⅲ collagen proteins. Thus any changes of collagen Ⅰ and（or） Ⅲ may damage the founction of cardiac interstitium.