Establishment of cardiac cytoarchitecture in the developing mouse heart
Establishment of cardiac cytoarchitecture in the developing mouse heart
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DOI：
10.1016/j.ydbio.2005.10.046
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发表时间：
2006-01-15
影响因子：
2.7
通讯作者：
Perriard, JC
中科院分区：
文献类型：
--
作者：
Hirschy, A;Schatzmann, F;Perriard, JC
心肌细胞的特点是组织极其良好的细胞结构。我们研究了它在发育中的小鼠心脏中的建立，特别是肌原纤维和细胞间接触的特殊类型，即闰盘（ICD）。早期胚胎心肌细胞呈多边形，细胞与细胞的接触在外周膜上呈圆周分布，肌原纤维在细胞核和质膜之间的稀疏细胞质中以随机方向运行。在胎儿发育过程中，心肌细胞伸长，肌原纤维对齐。 ICD 成分对细胞双极端的限制是一个慢得多的过程，并且对于粘附连接和桥粒仅在出生后实现，对于间隙连接甚至更晚。通过量化产前心肌细胞的特定生长参数，我们能够识别以前未知的生理肥大的胎儿阶段。我们的结果表明（1）心肌细胞中肌原纤维排列、双极化和 ICD 限制依次发生，（2）胚胎中心脏质量的增加不仅是通过单独的增生实现的，而且还通过单个心肌细胞体积的增加（肥大）来实现。这些观察结果有助于了解在细胞水平的发育过程中导致功能性心脏形成的机制。 (c) 2005 Elsevier Inc. 保留所有权利。
Cardiomyocytes are characterized by an extremely well-organized cytoarchitecture. We investigated its establishment in the developing mouse heart with particular reference to the myofibrils and the specialized types of cell-cell contacts, the intercalated discs (ICD). Early embryonic cardiomyocytes have a polygonal shape with cell-cell contacts distributed circumferentially at the peripheral membrane and myofibrils running in a random orientation in the sparse cytoplasm between the nucleus and the plasma membrane. During fetal development, the cardiomyocytes elongate, and the myofibrils become aligned. The restriction of the ICD components to the bipolar ends of the cells is a much slower process and is achieved for adherens junctions and desmosomes only after birth, for gap junctions even later. By quantifying the specific growth parameters of prenatal cardiomyocytes, we were able to identify a previously unknown fetal phase of physiological hypertrophy. Our results suggest (1) that myofibril alignment, bipolarization and ICD restriction happen sequentially in cardiomyocytes, and (2) that increase of heart mass in the embryo is not only achieved by hyperplasia alone but also by volume increase of the individual cardiomyocytes (hypertrophy). These observations help to understand the mechanisms that lead to the formation of a functional heart during development at a cellular level. (c) 2005 Elsevier Inc. All rights reserved.