Lieber R L, Fridén J O, Hargens A R, Danzig L A, Gershuni D H
Department of Surgery, Veterans Administration Medical Center, San Diego, CA 92161.
Muscle Nerve. 1988 Mar;11(3):193-201. doi: 10.1002/mus.880110302.
The change in muscle fiber size and fiber percentage was studied in three heads of the dog quadriceps following 10 weeks of immobilization using an external skeletal fixator. Muscle biopsy morphometric analysis revealed that muscle fiber atrophy was greatest for the vastus medialis and least for the rectus femoris. The atrophic response for type 1 fibers was, in order from most to least atrophied: VM greater than VL greater than RF, whereas for type 2 fibers the corresponding order was VM = VL greater than RF. An increase in connective tissue was also observed for all muscles. These results are discussed in terms of skeletal muscle architecture, initial fiber-type distribution, and level of use. As a result, predictions are made as to the muscles that are most vulnerable to disuse atrophy, namely the postural muscles that contain a relatively large proportion of slow muscle fibers and cross a single joint. Conversely, those that are least susceptible to atrophy are those that are not used as postural muscles, that cross multiple joints, and that are predominantly composed of fast muscle fibers.
使用外骨骼固定器固定10周后，对犬股四头肌的三个头的肌纤维大小和纤维百分比变化进行了研究。肌肉活检形态计量分析显示，股内侧肌的肌纤维萎缩最严重，股直肌最轻。1型纤维的萎缩反应，从萎缩程度由大到小依次为：股内侧肌大于股外侧肌大于股直肌，而2型纤维的相应顺序为股内侧肌 = 股外侧肌大于股直肌。所有肌肉的结缔组织也都有增加。根据骨骼肌结构、初始纤维类型分布和使用水平对这些结果进行了讨论。因此，对最易发生废用性萎缩的肌肉进行了预测，即那些含有相对较大比例慢肌纤维且跨过单个关节的姿势肌。相反，最不易发生萎缩的肌肉是那些不作为姿势肌使用、跨过多个关节且主要由快肌纤维组成的肌肉。
