Hiraizumi Y
Department of Orthopaedic Surgery, Showa University School of Medicine, Tokyo, Japan.
Nihon Seikeigeka Gakkai Zasshi. 1993 Jan;67(1):81-92.
Myosin ATPase reactions are generally used to differentiate between muscle fibers. However, those reactions have disadvantages including the need for delicate pH control and preincubation under non-physiological pH. Furthermore enzyme activity is only an indirect reflection of myofilament characteristics. In this study, an immunohistochemical method with anti-slow and anti-fast myosin heavy chain antibodies was used to observe: 1) whether muscle fiber types could be distinguished in degenerated muscles, 2) immunoreactivity of type 2C fibers in denervated muscles, and 3) discrepancies in structural disorders. Thirty one muscle biopsies which included neurogenic, myogenic, and control muscles were examined. Muscle fiber types were recognized in normal and in severely degenerated muscles. Type 2C muscle fibers were not necessarily constantly immunoreactive to both anti-slow and anti-fast myosin antibodies. In some targetoid fibers sites with absence of myosin ATPase activity had the same or rather higher immunoreactivity. Some muscle fibers undergoing fiber-type transformation showed discrepancies in reactivity between enzyme- and immuno-reactivity. This immunohistochemical method is capable of observing changes of muscle fibers during denervation, reinnervation, and also sports activity.
肌球蛋白ATP酶反应通常用于区分肌纤维。然而，这些反应存在缺点，包括需要精确控制pH值以及在非生理pH值下进行预孵育。此外，酶活性只是肌丝特性的间接反映。在本研究中，使用抗慢肌球蛋白重链抗体和抗快肌球蛋白重链抗体的免疫组织化学方法来观察：1）在变性肌肉中是否可以区分肌纤维类型；2）失神经支配肌肉中2C型纤维的免疫反应性；3）结构紊乱中的差异。对31例肌肉活检标本进行了检查，这些标本包括神经源性、肌源性和对照肌肉。在正常和严重变性的肌肉中都识别出了肌纤维类型。2C型肌纤维不一定对抗慢肌球蛋白和抗快肌球蛋白抗体都持续具有免疫反应性。在一些缺乏肌球蛋白ATP酶活性的靶样纤维部位，具有相同或更高的免疫反应性。一些正在进行纤维类型转变的肌纤维在酶反应性和免疫反应性之间表现出差异。这种免疫组织化学方法能够观察失神经支配、再支配以及运动活动期间肌纤维的变化。
