CHRONIC ISCHEMIC VIABLE MYOCARDIUM IN MAN - ASPECTS OF DEDIFFERENTIATION
CHRONIC ISCHEMIC VIABLE MYOCARDIUM IN MAN - ASPECTS OF DEDIFFERENTIATION
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DOI：
10.1016/1054-8807(94)00028-p
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发表时间：
1995-01-01
影响因子：
3.7
通讯作者：
BORGERS, M
中科院分区：
文献类型：
--
作者：
AUSMA, J;SCHAART, G;BORGERS, M
来自慢性功能障碍但存活(冬眠)心肌患者的活检组织学分析显示有特征性的细胞改变。这些变化包括肌节部分或全部丢失，糖原积聚，肌浆网解体和丢失。这些受影响的细胞经历的大多数适应性变化都暗示着去分化。本研究分析了肌动蛋白、心动素和α-平滑肌肌动蛋白等收缩和细胞骨架蛋白在冬眠和正常心肌中的表达和组织模式，因为这些成分的表达和组织与心肌细胞分化的某些阶段有关。在正常细胞中，肌动蛋白呈横纹染色，而心脏蛋白呈纤维状排列，平行于肾小管。α-平滑肌肌动蛋白在成人心肌细胞中不表达。在冬眠的心肌细胞中，肌动蛋白呈点状表达，心脏蛋白的表达明显减少到几乎不存在，这都有利于这些细胞的胚胎表型。冬眠细胞中α-平滑肌肌动蛋白的重新表达有力地支持了这一假说。对心肌三种不同结构蛋白的观察表明，冬眠心肌获得了肌肉细胞去分化的各个方面。
Histologic analysis of biopsies derived from patients with chronic dysfunctional but viable (hibernating) myocardium showed characteristic cell alterations. These changes consisted of a partial to complete loss of sarcomeres, accumulation of glycogen, and disorganization and loss of sarcoplasmic reticulum. Most of the adaptive changes that these affected cells undergo are suggestive of dedifferentiation. In the present study the expression and organizational pattern of contractile and cytoskeletal proteins such as titin, cardiotin, and alpha-smooth muscle actin were assessed in hibernating and normal myocardium because the expression and organization of these constituents have been related to certain stages of cardiomyocyte differentiation. In normal cells titin shows a cross-striated staining pattern, whereas cardiotin displays a fibrillar array, parallel to the sacromeres. Alpha-Smooth muscle actin is not expressed in adult cardiomyocytes. The expression of titin in a punctuated pattern and the marked decrease to virtual absence of cardiotin in hibernating cardiomyocytes speak in favor of an embryonic phenotype of these cells. The re-expression of alpha-smooth muscle actin in hibernating cells strongly supports this hypothesis. The observations on three different structural proteins of heart muscle suggest that hibernating myocardium acquired aspects of muscle cell dedifferentiation.