Zanellato A M, Borrione A C, Tonello M, Scannapieco G, Pauletto P, Sartore S
Institute of General Pathology, University of Padova, Italy.
Arteriosclerosis. 1990 Nov-Dec;10(6):996-1009. doi: 10.1161/01.atv.10.6.996.
Two monoclonal antimyosin antibodies, Western blotting experiments, and immunofluorescence procedures were used to investigate myosin isoform expression in normal and atherosclerotic aortas of adult rabbits. The SM-E7 antibody reacted with the two myosin heavy chain (MHC) isoforms of smooth muscle (SM) type (SM-MHC-1 and SM-MHC-2) expressed in the adult rabbit aorta. The NM-G2 antibody recognized an epitope shared by the nonmuscle (NM) myosin heavy chains (NM-MHC) present in fibroblasts, macrophages, lymphocytes, and platelets. Two smooth muscle cell (SMC) populations were identified in the medial layer of normal adult aorta, namely cells that contained SM myosin exclusively and cells that showed the coexistence of SM and NM myosin isoforms. The size of the cell population with double myosin isoform content increased markedly during experimental atherogenesis and represented by far the predominant SMC phenotype in the atherosclerotic plaque. Western blotting analysis performed on crude extracts from the atherosclerotic plaque showed the presence of SM-MHC-1 and NM-MHC isoforms in this tissue. Co-expression of SM and NM myosin at the molecular and the cellular level were found in aortic tissue during the early stages of development. These results indicate that in experimental atherosclerosis, the accumulation in the plaque of SMC with an "immature" pattern of myosin isoform expression is accompanied by similar modifications in the differentiation pattern of SMC of the underlying media.
使用两种单克隆抗肌球蛋白抗体、蛋白质印迹实验和免疫荧光方法，研究成年兔正常和动脉粥样硬化主动脉中肌球蛋白同工型的表达。SM-E7抗体与成年兔主动脉中表达的平滑肌（SM）型的两种肌球蛋白重链（MHC）同工型（SM-MHC-1和SM-MHC-2）发生反应。NM-G2抗体识别存在于成纤维细胞、巨噬细胞、淋巴细胞和血小板中的非肌肉（NM）肌球蛋白重链（NM-MHC）共有的一个表位。在正常成年主动脉中膜层鉴定出两种平滑肌细胞（SMC）群体，即仅含有SM肌球蛋白的细胞和显示SM与NM肌球蛋白同工型共存的细胞。在实验性动脉粥样硬化形成过程中，具有双重肌球蛋白同工型含量的细胞群体大小显著增加，并且是动脉粥样硬化斑块中迄今为止占主导地位的SMC表型。对动脉粥样硬化斑块粗提物进行的蛋白质印迹分析表明该组织中存在SM-MHC-1和NM-MHC同工型。在发育早期阶段的主动脉组织中发现了SM和NM肌球蛋白在分子和细胞水平上的共表达。这些结果表明，在实验性动脉粥样硬化中，肌球蛋白同工型表达呈“不成熟”模式的SMC在斑块中的积累，伴随着其下方中膜层SMC分化模式的类似改变。
