THE REORGANIZATION OF SUB-CELLULAR STRUCTURE IN MUSCLE UNDERGOING FAST-TO-SLOW TYPE TRANSFORMATION - A STEREOLOGICAL STUDY
THE REORGANIZATION OF SUB-CELLULAR STRUCTURE IN MUSCLE UNDERGOING FAST-TO-SLOW TYPE TRANSFORMATION - A STEREOLOGICAL STUDY
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DOI：
10.1007/bf00216750
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发表时间：
1981-01-01
影响因子：
3.6
通讯作者：
SALMONS, S
中科院分区：
文献类型：
--
作者：
EISENBERG, BR;SALMONS, S
用慢性低频电刺激诱导成年家兔骨骼肌快收缩向慢收缩转变，并在超微结构水平上进行了研究。随着体视学技术的使用，建立了一个时间过程中的线粒体体积的变化，sarcotubular系统，和Z-带厚度为6小时至24周的刺激期间。T-小管，终末池和肌浆网在早期阶段减少，仅2周的刺激后达到典型的慢肌水平。Z带结构的转换发生在刺激后1 1/2和3周之间。线粒体体积增加了几倍，在第一个3周的刺激，并迅速下降7周后，虽然它仍然高于典型的慢肌水平。虽然没有迹象表明肌肉纤维本身的降解和再生，相当大的结构重组是明显的亚细胞水平刺激后1周。纤维通过一个组织不太好的过渡阶段，纤维不能被分配到一个正常的超微结构类别。3周后，所有的刺激纤维可以被分配到正常的慢缩类，虽然一些亚细胞的不规则性持续甚至24周后。超微结构的变化进行了讨论，在整个肌肉的功能和生化变化。
Transformation of fast-twitch into slow-twitch skeletal muscle was induced in adult rabbits by chronic low-frequency stimulation and studied at the ultrastructural level. With the use of stereological techniques, a time course was established for changes in mitochondrial volume, sarcotubular system, and Z-band thickness for periods of stimulation ranging from 6 h to 24 wk. T-tubules, terminal cisternae and sarcoplasmic reticulum decreased at an early stage and reached levels typical of slow muscle after only 2 wk of stimulation. Transformation of Z-band structure took place between 1 1/2 and 3 wk after the onset of stimulation. Mitochondrial volume increased several-fold over the first 3 wk of stimulation, and fell rapidly after 7 wk, although it still remained above the levels typical of slow muscle. Although there was no sign of degradation and regeneration of the muscle fibers themselves, considerable structural reorganization was evident at the subcellular level after 1 wk of stimulation. The fibers passed through a less well organized transitional stage in which fibers could not be assigned to a normal ultrastructural category. After 3 wk all of the stimulated fibers could be assigned to the normal slow-twitch category although some subcellular irregularities persisted even after 24 wk. The ultrastructural alterations are discussed in relation to functional and biochemical changes in the whole muscle.