Li J, Robertson D R, Lemanski L F
Department of Anatomy and Cell Biology, State University of New York, SUNY Health Science Center at Syracuse 13210.
Acta Histochem. 1994 Mar;96(1):33-42. doi: 10.1016/s0065-1281(11)80006-1.
The cardiomyopathic (CM) hamster (Strain UM X7.1) develops a progressive cardiomyopathy characterized by cellular necrosis, hypertrophy and congestive heart failure. To better understand these abnormalities, this study was undertaken to investigate possible abnormalities in the morphology and distributions of cytoskeletal proteins in normal and cardiomyopathic hamster heart cells in vitro. Primary cultures of cardiac myocytes from normal and CM newborn hamsters were analyzed and compared by indirect immunofluorescent microscopy after 3, 5, 7 and 9 days in culture. The distributions of the cytoskeletal proteins, alpha-actinin and tubulin, were examined in cultured hamster cardiac myocytes. After the cells attach to coverslips, both normal and CM myocytes appear rounded in shape. After 5 days in culture, CM myocytes show fewer cytoplasmic projections than normal. To assess this phenomenon, the area and perimeter dimensions of normal and CM myocytes were analyzed by morphometric methods. It was determined that cardiomyopathic cells in culture become progressively larger in area but smaller than normal in their perimeter dimensions. A statistically significant difference was noted from day 3 onward. This result confirms that cardiomyopathic cells have abnormal shapes in vitro. It is conceivable that a reduction of the perimeter dimension in CM cells may be related to the reported calcium overload or to other biochemical or physiological lesions. In addition, the greatest density of tubulin staining is present immediately around the nucleus, with fluorescent "rays" radiating out to the cell periphery. Most of the myofibrils labelled by anti-alpha-actinin antibody showed parallel arrangements with respect to each other in normal myocytes whereas in CM heart cells the myofibrils were disarrayed. There were no differences in the distributions of tubulin and alpha-actinin in normal and cardiomyopathic myocytes in culture.
心肌病（CM）仓鼠（UM X7.1品系）会发展出一种进行性心肌病，其特征为细胞坏死、肥大和充血性心力衰竭。为了更好地理解这些异常情况，本研究旨在调查体外培养的正常和心肌病仓鼠心脏细胞中细胞骨架蛋白的形态和分布可能存在的异常。对来自正常和CM新生仓鼠的心肌细胞原代培养物在培养3、5、7和9天后通过间接免疫荧光显微镜进行分析和比较。检测了培养的仓鼠心肌细胞中细胞骨架蛋白α-辅肌动蛋白和微管蛋白的分布。细胞附着在盖玻片上后，正常和CM心肌细胞均呈圆形。培养5天后，CM心肌细胞的细胞质突起比正常细胞少。为了评估这一现象，通过形态计量学方法分析了正常和CM心肌细胞的面积和周长尺寸。结果确定，培养中的心肌病细胞面积逐渐增大，但周长尺寸比正常细胞小。从第3天起就观察到了统计学上的显著差异。这一结果证实了心肌病细胞在体外具有异常形状。可以想象，CM细胞周长尺寸的减小可能与报道的钙超载或其他生化或生理损伤有关。此外，微管蛋白染色的最大密度出现在细胞核周围，荧光“射线”向细胞周边辐射。在正常心肌细胞中，抗α-辅肌动蛋白抗体标记的大多数肌原纤维彼此平行排列，而在CM心脏细胞中，肌原纤维排列紊乱。在培养的正常和心肌病心肌细胞中，微管蛋白和α-辅肌动蛋白的分布没有差异。
