Z- and M-band appearance in different histochemically defined types of human skeletal muscle fibers.
Z- and M-band appearance in different histochemically defined types of human skeletal muscle fibers.
复制标题
不同组织化学定义类型的人类骨骼肌纤维中的 Z 和 M 带外观。
DOI：
10.1177/30.1.7054271
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
K. Angquist
中科院分区：
文献类型：
--
作者：
M. Sjöström;S. Kidman;K. H. Larsén;K. Angquist
为了确定超微结构特征，单独或与其他特征相结合，可以用来识别不同类型的纤维在人骨骼肌，冷冻活检标本的m。胫骨前肌连续切片。制备解冻切片用于酶组织化学或电子显微镜检查。然后在所有连续切片中鉴定相同的纤维，并在电子显微镜下检查其超微结构。本研究共纳入75根纤维。还常规制备用于电子显微镜检查的样本。特别关注的是肌节的Z-和M-带的外观。在同一纤维中，所有肌原纤维显示出相同的Z-以及M-带结构。另一方面，很明显，这些结构在同一肌肉中从一种类型的纤维到另一种类型的纤维是不同的，并且它们的外观在很大程度上是协变的。低水平分辨率的1型纤维通常表现出广泛的Z-和M-带与五个强大的M-桥线。在2A型纤维中观察到中间Z带。在M带的中间部分，三条强M桥线明显，而两条外侧线相对较弱。最后，2B型纤维通常出现窄Z带。中间的三条M桥线很强，而外面的两条很弱，如果能看到的话。判别分析表明，约70%的纤维应已被正确分配的基础上的Z-带宽单独。当两个独立的观察员分类的纤维的基础上的M-带的外观，超过95%的纤维被正确分类。因此，Z-和M-波段两者，单独或组合，可以用作纤维类型鉴别器。然而，M带结构被证明比Z带宽度更可靠，因此当仅考虑这些参数中的一个时，应将其用作纤维类型指示器。
In order to define ultrastructural features, which alone or in combination with other features could be used to identify different types of fibers in human skeletal muscle, frozen biopsy specimens of m. tibialis anterior were serially sectioned. The thawed sections were prepared either for enzyme histochemistry or for electron microscopy. The same fiber was then identified in all serial sections and its ultrastructure examined under the electron microscope. A total of 75 fibers were included in this investigation. Specimens were also conventionally prepared for electron microscopy. Special interest was devoted to the appearance of the sarcomeric Z- and M-bands. In the same fiber, all myofibrils showed the same Z- as well as M-band structure. On the other hand, it was evident that these structures varied from one type of fiber to another in the same muscle and that their appearance were covariant to a great extent. Low level resolution of Type 1 fibers usually showed broad Z- and M-bands with five strong M-bridge lines. In Type 2A fibers intermediate Z-bands were observed. In the middle portion of the M-bands, three strong M-bridge lines were distinct while the two outer lines were relatively weak. Finally, Type 2B fibers usually appeared with narrow Z-bands. The three M-bridge lines in the middle were strong while the two outer ones were very weak, if seen at all. Discriminant analysis showed that about 70% of the fibers should have been correctly allocated on the basis of the Z-band width alone. When two independent observers classified the fibers on the basis of M-band appearance, more than 95% of the fibers were correctly classified. Thus, both the Z- and M-bands, alone or in combination, can be used as fiber type discriminators. However, the M-band structure proved to be more reliable than the Z-band width, and should therefore be used as the fiber type indicator when only one of these parameters is considered.