Eppenberger M, Hauser I, Eppenberger H M
Institute for Cell Biology, ETH, Zurich, Switzerland.
Biomed Biochim Acta. 1987;46(8-9):S640-5.
Immunocytochemistry using antibodies against myofibrillar proteins such as heart-C-protein and myomesin but also the fluorescence of rhodamine conjugated phalloidin as marker for F-actin structures was employed to study the redifferentiation of cultured adult rat cardiomyocytes. It was demonstrated that freshly isolated rod shaped cells in culture round up before they attach to the substratum, while myofibrillar structures of the cells degenerate. As soon as they attached to the substratum and gradually flattened out, small cross-striated myofibrils reappeared in the central part of the cells. F-actin, in freshly isolated cells present only in the I-band of the myofibrils, extended throughout the cells into the processes in the form of filament cables. In later stages the myofibrillar distribution varied. Smaller myocytes were frequently filled with myofibrils whereas in larger cells with many processes the myofibrils were found either arranged in perinuclear regions or showed a mosaic distribution. Myofibrils appear to be directly aligned with bundles of actin stress fibers, thus further supporting the suggestion that the actin filaments might serve as a scaffold for myofibril formation.
利用针对肌原纤维蛋白（如心肌C蛋白和肌间蛋白）的抗体进行免疫细胞化学研究，同时使用罗丹明标记的鬼笔环肽作为F-肌动蛋白结构的荧光标记，以研究培养的成年大鼠心肌细胞的再分化。结果表明，培养中刚分离出的杆状细胞在附着于基质之前会变圆，同时细胞的肌原纤维结构会退化。一旦它们附着于基质并逐渐变平，小的横纹肌原纤维就会在细胞中央部分重新出现。F-肌动蛋白在刚分离的细胞中仅存在于肌原纤维的I带中，以丝状束的形式延伸至整个细胞并进入突起。在后期，肌原纤维的分布有所不同。较小的心肌细胞常充满肌原纤维，而在具有许多突起的较大细胞中，肌原纤维要么排列在核周区域，要么呈镶嵌分布。肌原纤维似乎与肌动蛋白应力纤维束直接对齐，从而进一步支持了肌动蛋白丝可能作为肌原纤维形成支架的观点。
