Yoshihara T, Kanda T, Nagata H, Nomoto M, Kaneko T, Kato Y, Yaku Y
Department of Otorhinolaryngology, Chiba University School of Medicine, Japan.
Acta Anat (Basel). 1988;132(4):317-20. doi: 10.1159/000146594.
Ultrastructurally, myoepithelial cells were shown to contain numerous fine filaments in their cytoplasm and resembled smooth muscle cells. The myoepithelial cell of the salivary gland has been considered to play an important role in the secretion of saliva. The present study showed that all the thin filaments (actin filaments) in the myoepithelial cell of the human parotid gland bound heavy meromyosin (HMM) and formed characteristic arrowhead structures. These filaments ran in two opposite directions with the poles at different ends. On the other hand, there was no binding of HMM with thicker filaments (10-nm filaments), plasma membrane, nuclear membrane, collagen fibrils, basement membrane or other cytoplasmic organelles. The present results strongly suggest that myoepithelial cells possess a contractile function parallel to the long axis of the cell for supporting the secretion of saliva in the parotid gland.
在超微结构上，肌上皮细胞在其细胞质中含有大量细纤维，类似于平滑肌细胞。唾液腺的肌上皮细胞被认为在唾液分泌中起重要作用。本研究表明，人腮腺肌上皮细胞中的所有细肌丝（肌动蛋白丝）都结合了重酶解肌球蛋白（HMM）并形成特征性的箭头状结构。这些细丝以相反的两个方向排列，其极位于不同的末端。另一方面，HMM与较粗的细丝（10纳米细丝）、质膜、核膜、胶原纤维、基底膜或其他细胞质细胞器没有结合。目前的结果有力地表明，肌上皮细胞具有与细胞长轴平行的收缩功能，以支持腮腺中的唾液分泌。
