van den Berge H, Wirtz P
Department of Otorhinolaryngology, University of Maastricht, The Netherlands.
J Anat. 1989 Jun;164:215-28.
The gross anatomy, microscopical anatomy, morphometry, enzyme histochemistry, immunohistochemistry and electron microscopy of the tensor tympani muscle of the rat was studied. The aim of the study was to create an integrated insight into the morphology of the muscle and to discuss functional implications. The tensor tympani muscle of the rat is an atypical muscle. It is a small muscle composed of very small muscle fibres with a complex microscopical and submicroscopical architecture. Histochemically the muscle consists mainly of fast oxidative glycolytic fibres, but discrepancies are found when anti-heavy chain myosin antibodies are used for fibre typing. Different adult heavy chain myosin isotypes coexist in one single muscle fibre. The electron microscopical study shows that bundles of myofilaments branch and interconnect with other bundles of myofilaments. The findings suggest that the muscle is able to contract fast and is fatigue-resistant. Both features seem to suggest that the muscle has a function in protecting the inner ear against noise damage.
对大鼠鼓膜张肌的大体解剖、显微解剖、形态测量、酶组织化学、免疫组织化学及电子显微镜检查进行了研究。本研究的目的是全面了解该肌肉的形态，并探讨其功能意义。大鼠鼓膜张肌是一块非典型肌肉。它是一块小肌肉，由非常细小的肌纤维组成，具有复杂的显微和亚显微结构。组织化学研究表明，该肌肉主要由快速氧化糖酵解纤维组成，但在使用抗重链肌球蛋白抗体进行纤维分型时发现了差异。不同的成年重链肌球蛋白同型异构体共存于一根肌纤维中。电子显微镜研究显示，肌丝束相互分支并与其他肌丝束相互连接。这些发现表明，该肌肉能够快速收缩且抗疲劳。这两个特征似乎都表明该肌肉具有保护内耳免受噪声损伤的功能。
