Hurme T, Kalimo H
Department of Surgery, University of Turku, Finland.
Muscle Nerve. 1992 Apr;15(4):482-9. doi: 10.1002/mus.880150412.
Adhesion molecules were studied in regenerating skeletal muscle immunohistochemically and ultrastructurally after a standardized trauma. In normal muscle, extracellular matrix (ECM) protein tenascin was restricted to myotendinous junctions (MTJ), while the integrin beta 1-subunit was present also on the sarcolemma. After injury, tenascin increased on the outer surface of regenerating myofibers, where cellular fibronectin also accumulated. Later, tenascin concentrated at the tips of regenerating myofibers, where new MTJs were formed. The beta 1-subunit disappeared on necrotized myofibers and reappeared on regenerating fibers in a thicker layer. The regenerating myofibers were invested by a basal lamina, except for the growth cones at the distal ends, which were laminin-negative until the formation of MTJs occurred. These results indicate that regenerating muscle cells are attached to the ECM in a way that allows both growth of the muscle cells across the scar and their use before the regeneration is completed.
在标准化创伤后，采用免疫组织化学和超微结构方法对再生骨骼肌中的黏附分子进行了研究。在正常肌肉中，细胞外基质（ECM）蛋白腱生蛋白局限于肌腱连接点（MTJ），而整合素β1亚基也存在于肌膜上。损伤后，腱生蛋白在再生肌纤维的外表面增加，细胞纤连蛋白也在那里积累。后来，腱生蛋白集中在再生肌纤维的末端，新的肌腱连接点在那里形成。β1亚基在坏死的肌纤维上消失，并在再生纤维上以更厚的层重新出现。再生的肌纤维被基膜包裹，除了远端的生长锥，在肌腱连接点形成之前，生长锥对层粘连蛋白呈阴性。这些结果表明，再生的肌肉细胞以一种既能使肌肉细胞跨越瘢痕生长又能在再生完成前加以利用的方式附着于细胞外基质。
